text: // SPDX-License-Identifier: GPL-2.0+
  /*
   * Copyright 2015-2017 Google, Inc
   *
   * USB Power Delivery protocol stack.
   */
  
  #include <linux/completion.h>
  #include <linux/debugfs.h>
  #include <linux/device.h>
  #include <linux/jiffies.h>
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/mutex.h>
  #include <linux/power_supply.h>
  #include <linux/proc_fs.h>
  #include <linux/property.h>
  #include <linux/sched/clock.h>
  #include <linux/seq_file.h>
  #include <linux/slab.h>
  #include <linux/spinlock.h>
  #include <linux/usb.h>
  #include <linux/usb/pd.h>
  #include <linux/usb/pd_ado.h>
  #include <linux/usb/pd_bdo.h>
  #include <linux/usb/pd_ext_sdb.h>
  #include <linux/usb/pd_vdo.h>
  #include <linux/usb/role.h>
  #include <linux/usb/tcpm.h>
  #include <linux/usb/typec_altmode.h>
  #include <linux/workqueue.h>
  
  #define FOREACH_STATE(S)			\
  	S(INVALID_STATE),			\
  	S(TOGGLING),			\
  	S(SRC_UNATTACHED),			\
  	S(SRC_ATTACH_WAIT),			\
  	S(SRC_ATTACHED),			\
  	S(SRC_STARTUP),				\
  	S(SRC_SEND_CAPABILITIES),		\
  	S(SRC_SEND_CAPABILITIES_TIMEOUT),	\
  	S(SRC_NEGOTIATE_CAPABILITIES),		\
  	S(SRC_TRANSITION_SUPPLY),		\
  	S(SRC_READY),				\
  	S(SRC_WAIT_NEW_CAPABILITIES),		\
  						\
  	S(SNK_UNATTACHED),			\
  	S(SNK_ATTACH_WAIT),			\
  	S(SNK_DEBOUNCED),			\
  	S(SNK_ATTACHED),			\
  	S(SNK_STARTUP),				\
  	S(SNK_DISCOVERY),			\
  	S(SNK_DISCOVERY_DEBOUNCE),		\
  	S(SNK_DISCOVERY_DEBOUNCE_DONE),		\
  	S(SNK_WAIT_CAPABILITIES),		\
  	S(SNK_NEGOTIATE_CAPABILITIES),		\
  	S(SNK_NEGOTIATE_PPS_CAPABILITIES),	\
  	S(SNK_TRANSITION_SINK),			\
  	S(SNK_TRANSITION_SINK_VBUS),		\
  	S(SNK_READY),				\
  						\
  	S(ACC_UNATTACHED),			\
  	S(DEBUG_ACC_ATTACHED),			\
  	S(AUDIO_ACC_ATTACHED),			\
  	S(AUDIO_ACC_DEBOUNCE),			\
  						\
  	S(HARD_RESET_SEND),			\
  	S(HARD_RESET_START),			\
  	S(SRC_HARD_RESET_VBUS_OFF),		\
  	S(SRC_HARD_RESET_VBUS_ON),		\
  	S(SNK_HARD_RESET_SINK_OFF),		\
  	S(SNK_HARD_RESET_WAIT_VBUS),		\
  	S(SNK_HARD_RESET_SINK_ON),		\
  						\
  	S(SOFT_RESET),				\
  	S(SOFT_RESET_SEND),			\
  						\
  	S(DR_SWAP_ACCEPT),			\
  	S(DR_SWAP_SEND),			\
  	S(DR_SWAP_SEND_TIMEOUT),		\
  	S(DR_SWAP_CANCEL),			\
  	S(DR_SWAP_CHANGE_DR),			\
  						\
  	S(PR_SWAP_ACCEPT),			\
  	S(PR_SWAP_SEND),			\
  	S(PR_SWAP_SEND_TIMEOUT),		\
  	S(PR_SWAP_CANCEL),			\
  	S(PR_SWAP_START),			\
  	S(PR_SWAP_SRC_SNK_TRANSITION_OFF),	\
  	S(PR_SWAP_SRC_SNK_SOURCE_OFF),		\
  	S(PR_SWAP_SRC_SNK_SOURCE_OFF_CC_DEBOUNCED), \
  	S(PR_SWAP_SRC_SNK_SINK_ON),		\
  	S(PR_SWAP_SNK_SRC_SINK_OFF),		\
  	S(PR_SWAP_SNK_SRC_SOURCE_ON),		\
  	S(PR_SWAP_SNK_SRC_SOURCE_ON_VBUS_RAMPED_UP),    \
  						\
  	S(VCONN_SWAP_ACCEPT),			\
  	S(VCONN_SWAP_SEND),			\
  	S(VCONN_SWAP_SEND_TIMEOUT),		\
  	S(VCONN_SWAP_CANCEL),			\
  	S(VCONN_SWAP_START),			\
  	S(VCONN_SWAP_WAIT_FOR_VCONN),		\
  	S(VCONN_SWAP_TURN_ON_VCONN),		\
  	S(VCONN_SWAP_TURN_OFF_VCONN),		\
  						\
  	S(SNK_TRY),				\
  	S(SNK_TRY_WAIT),			\
  	S(SNK_TRY_WAIT_DEBOUNCE),               \
  	S(SNK_TRY_WAIT_DEBOUNCE_CHECK_VBUS),    \
  	S(SRC_TRYWAIT),				\
  	S(SRC_TRYWAIT_DEBOUNCE),		\
  	S(SRC_TRYWAIT_UNATTACHED),		\
  						\
  	S(SRC_TRY),				\
  	S(SRC_TRY_WAIT),                        \
  	S(SRC_TRY_DEBOUNCE),			\
  	S(SNK_TRYWAIT),				\
  	S(SNK_TRYWAIT_DEBOUNCE),		\
  	S(SNK_TRYWAIT_VBUS),			\
  	S(BIST_RX),				\
  						\
  	S(GET_STATUS_SEND),			\
  	S(GET_STATUS_SEND_TIMEOUT),		\
  	S(GET_PPS_STATUS_SEND),			\
  	S(GET_PPS_STATUS_SEND_TIMEOUT),		\
  						\
  	S(ERROR_RECOVERY),			\
  	S(PORT_RESET),				\
  	S(PORT_RESET_WAIT_OFF)
  
  #define GENERATE_ENUM(e)	e
  #define GENERATE_STRING(s)	#s
  
  enum tcpm_state {
  	FOREACH_STATE(GENERATE_ENUM)
  };
  
  static const char * const tcpm_states[] = {
  	FOREACH_STATE(GENERATE_STRING)
  };
  
  enum vdm_states {
  	VDM_STATE_ERR_BUSY = -3,
  	VDM_STATE_ERR_SEND = -2,
  	VDM_STATE_ERR_TMOUT = -1,
  	VDM_STATE_DONE = 0,
  	/* Anything >0 represents an active state */
  	VDM_STATE_READY = 1,
  	VDM_STATE_BUSY = 2,
  	VDM_STATE_WAIT_RSP_BUSY = 3,
  };
  
  enum pd_msg_request {
  	PD_MSG_NONE = 0,
  	PD_MSG_CTRL_REJECT,
  	PD_MSG_CTRL_WAIT,
  	PD_MSG_CTRL_NOT_SUPP,
  	PD_MSG_DATA_SINK_CAP,
  	PD_MSG_DATA_SOURCE_CAP,
  };
  
  /* Events from low level driver */
  
  #define TCPM_CC_EVENT		BIT(0)
  #define TCPM_VBUS_EVENT		BIT(1)
  #define TCPM_RESET_EVENT	BIT(2)
  
  #define LOG_BUFFER_ENTRIES	1024
  #define LOG_BUFFER_ENTRY_SIZE	128
  
  /* Alternate mode support */
  
  #define SVID_DISCOVERY_MAX	16
  #define ALTMODE_DISCOVERY_MAX	(SVID_DISCOVERY_MAX * MODE_DISCOVERY_MAX)
  
  struct pd_mode_data {
  	int svid_index;		/* current SVID index		*/
  	int nsvids;
  	u16 svids[SVID_DISCOVERY_MAX];
  	int altmodes;		/* number of alternate modes	*/
  	struct typec_altmode_desc altmode_desc[ALTMODE_DISCOVERY_MAX];
  };
  
  struct pd_pps_data {
  	u32 min_volt;
  	u32 max_volt;
  	u32 max_curr;
  	u32 out_volt;
  	u32 op_curr;
  	bool supported;
  	bool active;
  };
  
  struct tcpm_port {
  	struct device *dev;
  
  	struct mutex lock;		/* tcpm state machine lock */
  	struct workqueue_struct *wq;
  
  	struct typec_capability typec_caps;
  	struct typec_port *typec_port;
  
  	struct tcpc_dev	*tcpc;
  	struct usb_role_switch *role_sw;
  
  	enum typec_role vconn_role;
  	enum typec_role pwr_role;
  	enum typec_data_role data_role;
  	enum typec_pwr_opmode pwr_opmode;
  
  	struct usb_pd_identity partner_ident;
  	struct typec_partner_desc partner_desc;
  	struct typec_partner *partner;
  
  	enum typec_cc_status cc_req;
  
  	enum typec_cc_status cc1;
  	enum typec_cc_status cc2;
  	enum typec_cc_polarity polarity;
  
  	bool attached;
  	bool connected;
  	enum typec_port_type port_type;
  	bool vbus_present;
  	bool vbus_never_low;
  	bool vbus_source;
  	bool vbus_charge;
  
  	bool send_discover;
  	bool op_vsafe5v;
  
  	int try_role;
  	int try_snk_count;
  	int try_src_count;
  
  	enum pd_msg_request queued_message;
  
  	enum tcpm_state enter_state;
  	enum tcpm_state prev_state;
  	enum tcpm_state state;
  	enum tcpm_state delayed_state;
  	unsigned long delayed_runtime;
  	unsigned long delay_ms;
  
  	spinlock_t pd_event_lock;
  	u32 pd_events;
  
  	struct work_struct event_work;
  	struct delayed_work state_machine;
  	struct delayed_work vdm_state_machine;
  	bool state_machine_running;
  
  	struct completion tx_complete;
  	enum tcpm_transmit_status tx_status;
  
  	struct mutex swap_lock;		/* swap command lock */
  	bool swap_pending;
  	bool non_pd_role_swap;
  	struct completion swap_complete;
  	int swap_status;
  
  	unsigned int negotiated_rev;
  	unsigned int message_id;
  	unsigned int caps_count;
  	unsigned int hard_reset_count;
  	bool pd_capable;
  	bool explicit_contract;
  	unsigned int rx_msgid;
  
  	/* Partner capabilities/requests */
  	u32 sink_request;
  	u32 source_caps[PDO_MAX_OBJECTS];
  	unsigned int nr_source_caps;
  	u32 sink_caps[PDO_MAX_OBJECTS];
  	unsigned int nr_sink_caps;
  
  	/* Local capabilities */
  	u32 src_pdo[PDO_MAX_OBJECTS];
  	unsigned int nr_src_pdo;
  	u32 snk_pdo[PDO_MAX_OBJECTS];
  	unsigned int nr_snk_pdo;
  	u32 snk_vdo[VDO_MAX_OBJECTS];
  	unsigned int nr_snk_vdo;
  
  	unsigned int operating_snk_mw;
  	bool update_sink_caps;
  
  	/* Requested current / voltage */
  	u32 current_limit;
  	u32 supply_voltage;
  
  	/* Used to export TA voltage and current */
  	struct power_supply *psy;
  	struct power_supply_desc psy_desc;
  	enum power_supply_usb_type usb_type;
  
  	u32 bist_request;
  
  	/* PD state for Vendor Defined Messages */
  	enum vdm_states vdm_state;
  	u32 vdm_retries;
  	/* next Vendor Defined Message to send */
  	u32 vdo_data[VDO_MAX_SIZE];
  	u8 vdo_count;
  	/* VDO to retry if UFP responder replied busy */
  	u32 vdo_retry;
  
  	/* PPS */
  	struct pd_pps_data pps_data;
  	struct completion pps_complete;
  	bool pps_pending;
  	int pps_status;
  
  	/* Alternate mode data */
  	struct pd_mode_data mode_data;
  	struct typec_altmode *partner_altmode[ALTMODE_DISCOVERY_MAX];
  	struct typec_altmode *port_altmode[ALTMODE_DISCOVERY_MAX];
  
  	/* Deadline in jiffies to exit src_try_wait state */
  	unsigned long max_wait;
  
  	/* port belongs to a self powered device */
  	bool self_powered;
  
  #ifdef CONFIG_DEBUG_FS
  	struct dentry *dentry;
  	struct mutex logbuffer_lock;	/* log buffer access lock */
  	int logbuffer_head;
  	int logbuffer_tail;
  	u8 *logbuffer[LOG_BUFFER_ENTRIES];
  #endif
  };
  
  struct pd_rx_event {
  	struct work_struct work;
  	struct tcpm_port *port;
  	struct pd_message msg;
  };
  
  #define tcpm_cc_is_sink(cc) \
  	((cc) == TYPEC_CC_RP_DEF || (cc) == TYPEC_CC_RP_1_5 || \
  	 (cc) == TYPEC_CC_RP_3_0)
  
  #define tcpm_port_is_sink(port) \
  	((tcpm_cc_is_sink((port)->cc1) && !tcpm_cc_is_sink((port)->cc2)) || \
  	 (tcpm_cc_is_sink((port)->cc2) && !tcpm_cc_is_sink((port)->cc1)))
  
  #define tcpm_cc_is_source(cc) ((cc) == TYPEC_CC_RD)
  #define tcpm_cc_is_audio(cc) ((cc) == TYPEC_CC_RA)
  #define tcpm_cc_is_open(cc) ((cc) == TYPEC_CC_OPEN)
  
  #define tcpm_port_is_source(port) \
  	((tcpm_cc_is_source((port)->cc1) && \
  	 !tcpm_cc_is_source((port)->cc2)) || \
  	 (tcpm_cc_is_source((port)->cc2) && \
  	  !tcpm_cc_is_source((port)->cc1)))
  
  #define tcpm_port_is_debug(port) \
  	(tcpm_cc_is_source((port)->cc1) && tcpm_cc_is_source((port)->cc2))
  
  #define tcpm_port_is_audio(port) \
  	(tcpm_cc_is_audio((port)->cc1) && tcpm_cc_is_audio((port)->cc2))
  
  #define tcpm_port_is_audio_detached(port) \
  	((tcpm_cc_is_audio((port)->cc1) && tcpm_cc_is_open((port)->cc2)) || \
  	 (tcpm_cc_is_audio((port)->cc2) && tcpm_cc_is_open((port)->cc1)))
  
  #define tcpm_try_snk(port) \
  	((port)->try_snk_count == 0 && (port)->try_role == TYPEC_SINK && \
  	(port)->port_type == TYPEC_PORT_DRP)
  
  #define tcpm_try_src(port) \
  	((port)->try_src_count == 0 && (port)->try_role == TYPEC_SOURCE && \
  	(port)->port_type == TYPEC_PORT_DRP)
  
  static enum tcpm_state tcpm_default_state(struct tcpm_port *port)
  {
  	if (port->port_type == TYPEC_PORT_DRP) {
  		if (port->try_role == TYPEC_SINK)
  			return SNK_UNATTACHED;
  		else if (port->try_role == TYPEC_SOURCE)
  			return SRC_UNATTACHED;
  		else if (port->tcpc->config &&
  			 port->tcpc->config->default_role == TYPEC_SINK)
  			return SNK_UNATTACHED;
  		/* Fall through to return SRC_UNATTACHED */
  	} else if (port->port_type == TYPEC_PORT_SNK) {
  		return SNK_UNATTACHED;
  	}
  	return SRC_UNATTACHED;
  }
  
  static inline
  struct tcpm_port *typec_cap_to_tcpm(const struct typec_capability *cap)
  {
  	return container_of(cap, struct tcpm_port, typec_caps);
  }
  
  static bool tcpm_port_is_disconnected(struct tcpm_port *port)
  {
  	return (!port->attached && port->cc1 == TYPEC_CC_OPEN &&
  		port->cc2 == TYPEC_CC_OPEN) ||
  	       (port->attached && ((port->polarity == TYPEC_POLARITY_CC1 &&
  				    port->cc1 == TYPEC_CC_OPEN) ||
  				   (port->polarity == TYPEC_POLARITY_CC2 &&
  				    port->cc2 == TYPEC_CC_OPEN)));
  }
  
  /*
   * Logging
   */
  
  #ifdef CONFIG_DEBUG_FS
  
  static bool tcpm_log_full(struct tcpm_port *port)
  {
  	return port->logbuffer_tail ==
  		(port->logbuffer_head + 1) % LOG_BUFFER_ENTRIES;
  }
  
  __printf(2, 0)
  static void _tcpm_log(struct tcpm_port *port, const char *fmt, va_list args)
  {
  	char tmpbuffer[LOG_BUFFER_ENTRY_SIZE];
  	u64 ts_nsec = local_clock();
  	unsigned long rem_nsec;
  
  	mutex_lock(&port->logbuffer_lock);
  	if (!port->logbuffer[port->logbuffer_head]) {
  		port->logbuffer[port->logbuffer_head] =
  				kzalloc(LOG_BUFFER_ENTRY_SIZE, GFP_KERNEL);
  		if (!port->logbuffer[port->logbuffer_head]) {
  			mutex_unlock(&port->logbuffer_lock);
  			return;
  		}
  	}
  
  	vsnprintf(tmpbuffer, sizeof(tmpbuffer), fmt, args);
  
  	if (tcpm_log_full(port)) {
  		port->logbuffer_head = max(port->logbuffer_head - 1, 0);
  		strcpy(tmpbuffer, "overflow");
  	}
  
  	if (port->logbuffer_head < 0 ||
  	    port->logbuffer_head >= LOG_BUFFER_ENTRIES) {
  		dev_warn(port->dev,
  			 "Bad log buffer index %d\n", port->logbuffer_head);
  		goto abort;
  	}
  
  	if (!port->logbuffer[port->logbuffer_head]) {
  		dev_warn(port->dev,
  			 "Log buffer index %d is NULL\n", port->logbuffer_head);
  		goto abort;
  	}
  
  	rem_nsec = do_div(ts_nsec, 1000000000);
  	scnprintf(port->logbuffer[port->logbuffer_head],
  		  LOG_BUFFER_ENTRY_SIZE, "[%5lu.%06lu] %s",
  		  (unsigned long)ts_nsec, rem_nsec / 1000,
  		  tmpbuffer);
  	port->logbuffer_head = (port->logbuffer_head + 1) % LOG_BUFFER_ENTRIES;
  
  abort:
  	mutex_unlock(&port->logbuffer_lock);
  }
  
  __printf(2, 3)
  static void tcpm_log(struct tcpm_port *port, const char *fmt, ...)
  {
  	va_list args;
  
  	/* Do not log while disconnected and unattached */
  	if (tcpm_port_is_disconnected(port) &&
  	    (port->state == SRC_UNATTACHED || port->state == SNK_UNATTACHED ||
  	     port->state == TOGGLING))
  		return;
  
  	va_start(args, fmt);
  	_tcpm_log(port, fmt, args);
  	va_end(args);
  }
  
  __printf(2, 3)
  static void tcpm_log_force(struct tcpm_port *port, const char *fmt, ...)
  {
  	va_list args;
  
  	va_start(args, fmt);
  	_tcpm_log(port, fmt, args);
  	va_end(args);
  }
  
  static void tcpm_log_source_caps(struct tcpm_port *port)
  {
  	int i;
  
  	for (i = 0; i < port->nr_source_caps; i++) {
  		u32 pdo = port->source_caps[i];
  		enum pd_pdo_type type = pdo_type(pdo);
  		char msg[64];
  
  		switch (type) {
  		case PDO_TYPE_FIXED:
  			scnprintf(msg, sizeof(msg),
  				  "%u mV, %u mA [%s%s%s%s%s%s]",
  				  pdo_fixed_voltage(pdo),
  				  pdo_max_current(pdo),
  				  (pdo & PDO_FIXED_DUAL_ROLE) ?
  							"R" : "",
  				  (pdo & PDO_FIXED_SUSPEND) ?
  							"S" : "",
  				  (pdo & PDO_FIXED_HIGHER_CAP) ?
  							"H" : "",
  				  (pdo & PDO_FIXED_USB_COMM) ?
  							"U" : "",
  				  (pdo & PDO_FIXED_DATA_SWAP) ?
  							"D" : "",
  				  (pdo & PDO_FIXED_EXTPOWER) ?
  							"E" : "");
  			break;
  		case PDO_TYPE_VAR:
  			scnprintf(msg, sizeof(msg),
  				  "%u-%u mV, %u mA",
  				  pdo_min_voltage(pdo),
  				  pdo_max_voltage(pdo),
  				  pdo_max_current(pdo));
  			break;
  		case PDO_TYPE_BATT:
  			scnprintf(msg, sizeof(msg),
  				  "%u-%u mV, %u mW",
  				  pdo_min_voltage(pdo),
  				  pdo_max_voltage(pdo),
  				  pdo_max_power(pdo));
  			break;
  		case PDO_TYPE_APDO:
  			if (pdo_apdo_type(pdo) == APDO_TYPE_PPS)
  				scnprintf(msg, sizeof(msg),
  					  "%u-%u mV, %u mA",
  					  pdo_pps_apdo_min_voltage(pdo),
  					  pdo_pps_apdo_max_voltage(pdo),
  					  pdo_pps_apdo_max_current(pdo));
  			else
  				strcpy(msg, "undefined APDO");
  			break;
  		default:
  			strcpy(msg, "undefined");
  			break;
  		}
  		tcpm_log(port, " PDO %d: type %d, %s",
  			 i, type, msg);
  	}
  }
  
  static int tcpm_debug_show(struct seq_file *s, void *v)
  {
  	struct tcpm_port *port = (struct tcpm_port *)s->private;
  	int tail;
  
  	mutex_lock(&port->logbuffer_lock);
  	tail = port->logbuffer_tail;
  	while (tail != port->logbuffer_head) {
  		seq_printf(s, "%s\n", port->logbuffer[tail]);
  		tail = (tail + 1) % LOG_BUFFER_ENTRIES;
  	}
  	if (!seq_has_overflowed(s))
  		port->logbuffer_tail = tail;
  	mutex_unlock(&port->logbuffer_lock);
  
  	return 0;
  }
  DEFINE_SHOW_ATTRIBUTE(tcpm_debug);
  
  static void tcpm_debugfs_init(struct tcpm_port *port)
  {
  	char name[NAME_MAX];
  
  	mutex_init(&port->logbuffer_lock);
  	snprintf(name, NAME_MAX, "tcpm-%s", dev_name(port->dev));
  	port->dentry = debugfs_create_file(name, S_IFREG | 0444, usb_debug_root,
  					   port, &tcpm_debug_fops);
  }
  
  static void tcpm_debugfs_exit(struct tcpm_port *port)
  {
  	int i;
  
  	mutex_lock(&port->logbuffer_lock);
  	for (i = 0; i < LOG_BUFFER_ENTRIES; i++) {
  		kfree(port->logbuffer[i]);
  		port->logbuffer[i] = NULL;
  	}
  	mutex_unlock(&port->logbuffer_lock);
  
  	debugfs_remove(port->dentry);
  }
  
  #else
  
  __printf(2, 3)
  static void tcpm_log(const struct tcpm_port *port, const char *fmt, ...) { }
  __printf(2, 3)
  static void tcpm_log_force(struct tcpm_port *port, const char *fmt, ...) { }
  static void tcpm_log_source_caps(struct tcpm_port *port) { }
  static void tcpm_debugfs_init(const struct tcpm_port *port) { }
  static void tcpm_debugfs_exit(const struct tcpm_port *port) { }
  
  #endif
  
  static int tcpm_pd_transmit(struct tcpm_port *port,
  			    enum tcpm_transmit_type type,
  			    const struct pd_message *msg)
  {
  	unsigned long timeout;
  	int ret;
  
  	if (msg)
  		tcpm_log(port, "PD TX, header: %#x", le16_to_cpu(msg->header));
  	else
  		tcpm_log(port, "PD TX, type: %#x", type);
  
  	reinit_completion(&port->tx_complete);
  	ret = port->tcpc->pd_transmit(port->tcpc, type, msg);
  	if (ret < 0)
  		return ret;
  
  	mutex_unlock(&port->lock);
  	timeout = wait_for_completion_timeout(&port->tx_complete,
  				msecs_to_jiffies(PD_T_TCPC_TX_TIMEOUT));
  	mutex_lock(&port->lock);
  	if (!timeout)
  		return -ETIMEDOUT;
  
  	switch (port->tx_status) {
  	case TCPC_TX_SUCCESS:
  		port->message_id = (port->message_id + 1) & PD_HEADER_ID_MASK;
  		return 0;
  	case TCPC_TX_DISCARDED:
  		return -EAGAIN;
  	case TCPC_TX_FAILED:
  	default:
  		return -EIO;
  	}
  }
  
  void tcpm_pd_transmit_complete(struct tcpm_port *port,
  			       enum tcpm_transmit_status status)
  {
  	tcpm_log(port, "PD TX complete, status: %u", status);
  	port->tx_status = status;
  	complete(&port->tx_complete);
  }
  EXPORT_SYMBOL_GPL(tcpm_pd_transmit_complete);
  
  static int tcpm_mux_set(struct tcpm_port *port, int state,
  			enum usb_role usb_role,
  			enum typec_orientation orientation)
  {
  	int ret;
  
  	tcpm_log(port, "Requesting mux state %d, usb-role %d, orientation %d",
  		 state, usb_role, orientation);
  
  	ret = typec_set_orientation(port->typec_port, orientation);
  	if (ret)
  		return ret;
  
  	if (port->role_sw) {
  		ret = usb_role_switch_set_role(port->role_sw, usb_role);
  		if (ret)
  			return ret;
  	}
  
  	return typec_set_mode(port->typec_port, state);
  }
  
  static int tcpm_set_polarity(struct tcpm_port *port,
  			     enum typec_cc_polarity polarity)
  {
  	int ret;
  
  	tcpm_log(port, "polarity %d", polarity);
  
  	ret = port->tcpc->set_polarity(port->tcpc, polarity);
  	if (ret < 0)
  		return ret;
  
  	port->polarity = polarity;
  
  	return 0;
  }
  
  static int tcpm_set_vconn(struct tcpm_port *port, bool enable)
  {
  	int ret;
  
  	tcpm_log(port, "vconn:=%d", enable);
  
  	ret = port->tcpc->set_vconn(port->tcpc, enable);
  	if (!ret) {
  		port->vconn_role = enable ? TYPEC_SOURCE : TYPEC_SINK;
  		typec_set_vconn_role(port->typec_port, port->vconn_role);
  	}
  
  	return ret;
  }
  
  static u32 tcpm_get_current_limit(struct tcpm_port *port)
  {
  	enum typec_cc_status cc;
  	u32 limit;
  
  	cc = port->polarity ? port->cc2 : port->cc1;
  	switch (cc) {
  	case TYPEC_CC_RP_1_5:
  		limit = 1500;
  		break;
  	case TYPEC_CC_RP_3_0:
  		limit = 3000;
  		break;
  	case TYPEC_CC_RP_DEF:
  	default:
  		if (port->tcpc->get_current_limit)
  			limit = port->tcpc->get_current_limit(port->tcpc);
  		else
  			limit = 0;
  		break;
  	}
  
  	return limit;
  }
  
  static int tcpm_set_current_limit(struct tcpm_port *port, u32 max_ma, u32 mv)
  {
  	int ret = -EOPNOTSUPP;
  
  	tcpm_log(port, "Setting voltage/current limit %u mV %u mA", mv, max_ma);
  
  	port->supply_voltage = mv;
  	port->current_limit = max_ma;
  
  	if (port->tcpc->set_current_limit)
  		ret = port->tcpc->set_current_limit(port->tcpc, max_ma, mv);
  
  	return ret;
  }
  
  /*
   * Determine RP value to set based on maximum current supported
   * by a port if configured as source.
   * Returns CC value to report to link partner.
   */
  static enum typec_cc_status tcpm_rp_cc(struct tcpm_port *port)
  {
  	const u32 *src_pdo = port->src_pdo;
  	int nr_pdo = port->nr_src_pdo;
  	int i;
  
  	/*
  	 * Search for first entry with matching voltage.
  	 * It should report the maximum supported current.
  	 */
  	for (i = 0; i < nr_pdo; i++) {
  		const u32 pdo = src_pdo[i];
  
  		if (pdo_type(pdo) == PDO_TYPE_FIXED &&
  		    pdo_fixed_voltage(pdo) == 5000) {
  			unsigned int curr = pdo_max_current(pdo);
  
  			if (curr >= 3000)
  				return TYPEC_CC_RP_3_0;
  			else if (curr >= 1500)
  				return TYPEC_CC_RP_1_5;
  			return TYPEC_CC_RP_DEF;
  		}
  	}
  
  	return TYPEC_CC_RP_DEF;
  }
  
  static int tcpm_set_attached_state(struct tcpm_port *port, bool attached)
  {
  	return port->tcpc->set_roles(port->tcpc, attached, port->pwr_role,
  				     port->data_role);
  }
  
  static int tcpm_set_roles(struct tcpm_port *port, bool attached,
  			  enum typec_role role, enum typec_data_role data)
  {
  	enum typec_orientation orientation;
  	enum usb_role usb_role;
  	int ret;
  
  	if (port->polarity == TYPEC_POLARITY_CC1)
  		orientation = TYPEC_ORIENTATION_NORMAL;
  	else
  		orientation = TYPEC_ORIENTATION_REVERSE;
  
  	if (data == TYPEC_HOST)
  		usb_role = USB_ROLE_HOST;
  	else
  		usb_role = USB_ROLE_DEVICE;
  
  	ret = tcpm_mux_set(port, TYPEC_STATE_USB, usb_role, orientation);
  	if (ret < 0)
  		return ret;
  
  	ret = port->tcpc->set_roles(port->tcpc, attached, role, data);
  	if (ret < 0)
  		return ret;
  
  	port->pwr_role = role;
  	port->data_role = data;
  	typec_set_data_role(port->typec_port, data);
  	typec_set_pwr_role(port->typec_port, role);
  
  	return 0;
  }
  
  static int tcpm_set_pwr_role(struct tcpm_port *port, enum typec_role role)
  {
  	int ret;
  
  	ret = port->tcpc->set_roles(port->tcpc, true, role,
  				    port->data_role);
  	if (ret < 0)
  		return ret;
  
  	port->pwr_role = role;
  	typec_set_pwr_role(port->typec_port, role);
  
  	return 0;
  }
  
  static int tcpm_pd_send_source_caps(struct tcpm_port *port)
  {
  	struct pd_message msg;
  	int i;
  
  	memset(&msg, 0, sizeof(msg));
  	if (!port->nr_src_pdo) {
  		/* No source capabilities defined, sink only */
  		msg.header = PD_HEADER_LE(PD_CTRL_REJECT,
  					  port->pwr_role,
  					  port->data_role,
  					  port->negotiated_rev,
  					  port->message_id, 0);
  	} else {
  		msg.header = PD_HEADER_LE(PD_DATA_SOURCE_CAP,
  					  port->pwr_role,
  					  port->data_role,
  					  port->negotiated_rev,
  					  port->message_id,
  					  port->nr_src_pdo);
  	}
  	for (i = 0; i < port->nr_src_pdo; i++)
  		msg.payload[i] = cpu_to_le32(port->src_pdo[i]);
  
  	return tcpm_pd_transmit(port, TCPC_TX_SOP, &msg);
  }
  
  static int tcpm_pd_send_sink_caps(struct tcpm_port *port)
  {
  	struct pd_message msg;
  	int i;
  
  	memset(&msg, 0, sizeof(msg));
  	if (!port->nr_snk_pdo) {
  		/* No sink capabilities defined, source only */
  		msg.header = PD_HEADER_LE(PD_CTRL_REJECT,
  					  port->pwr_role,
  					  port->data_role,
  					  port->negotiated_rev,
  					  port->message_id, 0);
  	} else {
  		msg.header = PD_HEADER_LE(PD_DATA_SINK_CAP,
  					  port->pwr_role,
  					  port->data_role,
  					  port->negotiated_rev,
  					  port->message_id,
  					  port->nr_snk_pdo);
  	}
  	for (i = 0; i < port->nr_snk_pdo; i++)
  		msg.payload[i] = cpu_to_le32(port->snk_pdo[i]);
  
  	return tcpm_pd_transmit(port, TCPC_TX_SOP, &msg);
  }
  
  static void tcpm_set_state(struct tcpm_port *port, enum tcpm_state state,
  			   unsigned int delay_ms)
  {
  	if (delay_ms) {
  		tcpm_log(port, "pending state change %s -> %s @ %u ms",
  			 tcpm_states[port->state], tcpm_states[state],
  			 delay_ms);
  		port->delayed_state = state;
  		mod_delayed_work(port->wq, &port->state_machine,
  				 msecs_to_jiffies(delay_ms));
  		port->delayed_runtime = jiffies + msecs_to_jiffies(delay_ms);
  		port->delay_ms = delay_ms;
  	} else {
  		tcpm_log(port, "state change %s -> %s",
  			 tcpm_states[port->state], tcpm_states[state]);
  		port->delayed_state = INVALID_STATE;
  		port->prev_state = port->state;
  		port->state = state;
  		/*
  		 * Don't re-queue the state machine work item if we're currently
  		 * in the state machine and we're immediately changing states.
  		 * tcpm_state_machine_work() will continue running the state
  		 * machine.
  		 */
  		if (!port->state_machine_running)
  			mod_delayed_work(port->wq, &port->state_machine, 0);
  	}
  }
  
  static void tcpm_set_state_cond(struct tcpm_port *port, enum tcpm_state state,
  				unsigned int delay_ms)
  {
  	if (port->enter_state == port->state)
  		tcpm_set_state(port, state, delay_ms);
  	else
  		tcpm_log(port,
  			 "skipped %sstate change %s -> %s [%u ms], context state %s",
  			 delay_ms ? "delayed " : "",
  			 tcpm_states[port->state], tcpm_states[state],
  			 delay_ms, tcpm_states[port->enter_state]);
  }
  
  static void tcpm_queue_message(struct tcpm_port *port,
  			       enum pd_msg_request message)
  {
  	port->queued_message = message;
  	mod_delayed_work(port->wq, &port->state_machine, 0);
  }
  
  /*
   * VDM/VDO handling functions
   */
  static void tcpm_queue_vdm(struct tcpm_port *port, const u32 header,
  			   const u32 *data, int cnt)
  {
  	port->vdo_count = cnt + 1;
  	port->vdo_data[0] = header;
  	memcpy(&port->vdo_data[1], data, sizeof(u32) * cnt);
  	/* Set ready, vdm state machine will actually send */
  	port->vdm_retries = 0;
  	port->vdm_state = VDM_STATE_READY;
  }
  
  static void svdm_consume_identity(struct tcpm_port *port, const __le32 *payload,
  				  int cnt)
  {
  	u32 vdo = le32_to_cpu(payload[VDO_INDEX_IDH]);
  	u32 product = le32_to_cpu(payload[VDO_INDEX_PRODUCT]);
  
  	memset(&port->mode_data, 0, sizeof(port->mode_data));
  
  	port->partner_ident.id_header = vdo;
  	port->partner_ident.cert_stat = le32_to_cpu(payload[VDO_INDEX_CSTAT]);
  	port->partner_ident.product = product;
  
  	typec_partner_set_identity(port->partner);
  
  	tcpm_log(port, "Identity: %04x:%04x.%04x",
  		 PD_IDH_VID(vdo),
  		 PD_PRODUCT_PID(product), product & 0xffff);
  }
  
  static bool svdm_consume_svids(struct tcpm_port *port, const __le32 *payload,
  			       int cnt)
  {
  	struct pd_mode_data *pmdata = &port->mode_data;
  	int i;
  
  	for (i = 1; i < cnt; i++) {
  		u32 p = le32_to_cpu(payload[i]);
  		u16 svid;
  
  		svid = (p >> 16) & 0xffff;
  		if (!svid)
  			return false;
  
  		if (pmdata->nsvids >= SVID_DISCOVERY_MAX)
  			goto abort;
  
  		pmdata->svids[pmdata->nsvids++] = svid;
  		tcpm_log(port, "SVID %d: 0x%x", pmdata->nsvids, svid);
  
  		svid = p & 0xffff;
  		if (!svid)
  			return false;
  
  		if (pmdata->nsvids >= SVID_DISCOVERY_MAX)
  			goto abort;
  
  		pmdata->svids[pmdata->nsvids++] = svid;
  		tcpm_log(port, "SVID %d: 0x%x", pmdata->nsvids, svid);
  	}
  	return true;
  abort:
  	tcpm_log(port, "SVID_DISCOVERY_MAX(%d) too low!", SVID_DISCOVERY_MAX);
  	return false;
  }
  
  static void svdm_consume_modes(struct tcpm_port *port, const __le32 *payload,
  			       int cnt)
  {
  	struct pd_mode_data *pmdata = &port->mode_data;
  	struct typec_altmode_desc *paltmode;
  	int i;
  
  	if (pmdata->altmodes >= ARRAY_SIZE(port->partner_altmode)) {
  		/* Already logged in svdm_consume_svids() */
  		return;
  	}
  
  	for (i = 1; i < cnt; i++) {
  		paltmode = &pmdata->altmode_desc[pmdata->altmodes];
  		memset(paltmode, 0, sizeof(*paltmode));
  
  		paltmode->svid = pmdata->svids[pmdata->svid_index];
  		paltmode->mode = i;
  		paltmode->vdo = le32_to_cpu(payload[i]);
  
  		tcpm_log(port, " Alternate mode %d: SVID 0x%04x, VDO %d: 0x%08x",
  			 pmdata->altmodes, paltmode->svid,
  			 paltmode->mode, paltmode->vdo);
  
  		pmdata->altmodes++;
  	}
  }
  
  static void tcpm_register_partner_altmodes(struct tcpm_port *port)
  {
  	struct pd_mode_data *modep = &port->mode_data;
  	struct typec_altmode *altmode;
  	int i;
  
  	for (i = 0; i < modep->altmodes; i++) {
  		altmode = typec_partner_register_altmode(port->partner,
  						&modep->altmode_desc[i]);
  		if (!altmode)
  			tcpm_log(port, "Failed to register partner SVID 0x%04x",
  				 modep->altmode_desc[i].svid);
  		port->partner_altmode[i] = altmode;
  	}
  }
  
  #define supports_modal(port)	PD_IDH_MODAL_SUPP((port)->partner_ident.id_header)
  
  static int tcpm_pd_svdm(struct tcpm_port *port, const __le32 *payload, int cnt,
  			u32 *response)
  {
  	struct typec_altmode *adev;
  	struct typec_altmode *pdev;
  	struct pd_mode_data *modep;
  	u32 p[PD_MAX_PAYLOAD];
  	int rlen = 0;
  	int cmd_type;
  	int cmd;
  	int i;
  
  	for (i = 0; i < cnt; i++)
  		p[i] = le32_to_cpu(payload[i]);
  
  	cmd_type = PD_VDO_CMDT(p[0]);
  	cmd = PD_VDO_CMD(p[0]);
  
  	tcpm_log(port, "Rx VDM cmd 0x%x type %d cmd %d len %d",
  		 p[0], cmd_type, cmd, cnt);
  
  	modep = &port->mode_data;
  
  	adev = typec_match_altmode(port->port_altmode, ALTMODE_DISCOVERY_MAX,
  				   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
  
  	pdev = typec_match_altmode(port->partner_altmode, ALTMODE_DISCOVERY_MAX,
  				   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
  
  	switch (cmd_type) {
  	case CMDT_INIT:
  		switch (cmd) {
  		case CMD_DISCOVER_IDENT:
  			/* 6.4.4.3.1: Only respond as UFP (device) */
  			if (port->data_role == TYPEC_DEVICE &&
  			    port->nr_snk_vdo) {
  				for (i = 0; i <  port->nr_snk_vdo; i++)
  					response[i + 1] = port->snk_vdo[i];
  				rlen = port->nr_snk_vdo + 1;
  			}
  			break;
  		case CMD_DISCOVER_SVID:
  			break;
  		case CMD_DISCOVER_MODES:
  			break;
  		case CMD_ENTER_MODE:
  			break;
  		case CMD_EXIT_MODE:
  			break;
  		case CMD_ATTENTION:
  			/* Attention command does not have response */
  			if (adev)
  				typec_altmode_attention(adev, p[1]);
  			return 0;
  		default:
  			break;
  		}
  		if (rlen >= 1) {
  			response[0] = p[0] | VDO_CMDT(CMDT_RSP_ACK);
  		} else if (rlen == 0) {
  			response[0] = p[0] | VDO_CMDT(CMDT_RSP_NAK);
  			rlen = 1;
  		} else {
  			response[0] = p[0] | VDO_CMDT(CMDT_RSP_BUSY);
  			rlen = 1;
  		}
  		break;
  	case CMDT_RSP_ACK:
  		/* silently drop message if we are not connected */
  		if (IS_ERR_OR_NULL(port->partner))
  			break;
  
  		switch (cmd) {
  		case CMD_DISCOVER_IDENT:
  			/* 6.4.4.3.1 */
  			svdm_consume_identity(port, payload, cnt);
  			response[0] = VDO(USB_SID_PD, 1, CMD_DISCOVER_SVID);
  			rlen = 1;
  			break;
  		case CMD_DISCOVER_SVID:
  			/* 6.4.4.3.2 */
  			if (svdm_consume_svids(port, payload, cnt)) {
  				response[0] = VDO(USB_SID_PD, 1,
  						  CMD_DISCOVER_SVID);
  				rlen = 1;
  			} else if (modep->nsvids && supports_modal(port)) {
  				response[0] = VDO(modep->svids[0], 1,
  						  CMD_DISCOVER_MODES);
  				rlen = 1;
  			}
  			break;
  		case CMD_DISCOVER_MODES:
  			/* 6.4.4.3.3 */
  			svdm_consume_modes(port, payload, cnt);
  			modep->svid_index++;
  			if (modep->svid_index < modep->nsvids) {
  				u16 svid = modep->svids[modep->svid_index];
  				response[0] = VDO(svid, 1, CMD_DISCOVER_MODES);
  				rlen = 1;
  			} else {
  				tcpm_register_partner_altmodes(port);
  			}
  			break;
  		case CMD_ENTER_MODE:
  			if (adev && pdev) {
  				typec_altmode_update_active(pdev, true);
  
  				if (typec_altmode_vdm(adev, p[0], &p[1], cnt)) {
  					response[0] = VDO(adev->svid, 1,
  							  CMD_EXIT_MODE);
  					response[0] |= VDO_OPOS(adev->mode);
  					return 1;
  				}
  			}
  			return 0;
  		case CMD_EXIT_MODE:
  			if (adev && pdev) {
  				typec_altmode_update_active(pdev, false);
  
  				/* Back to USB Operation */
  				WARN_ON(typec_altmode_notify(adev,
  							     TYPEC_STATE_USB,
  							     NULL));
  			}
  			break;
  		default:
  			break;
  		}
  		break;
  	case CMDT_RSP_NAK:
  		switch (cmd) {
  		case CMD_ENTER_MODE:
  			/* Back to USB Operation */
  			if (adev)
  				WARN_ON(typec_altmode_notify(adev,
  							     TYPEC_STATE_USB,
  							     NULL));
  			break;
  		default:
  			break;
  		}
  		break;
  	default:
  		break;
  	}
  
  	/* Informing the alternate mode drivers about everything */
  	if (adev)
  		typec_altmode_vdm(adev, p[0], &p[1], cnt);
  
  	return rlen;
  }
  
  static void tcpm_handle_vdm_request(struct tcpm_port *port,
  				    const __le32 *payload, int cnt)
  {
  	int rlen = 0;
  	u32 response[8] = { };
  	u32 p0 = le32_to_cpu(payload[0]);
  
  	if (port->vdm_state == VDM_STATE_BUSY) {
  		/* If UFP responded busy retry after timeout */
  		if (PD_VDO_CMDT(p0) == CMDT_RSP_BUSY) {
  			port->vdm_state = VDM_STATE_WAIT_RSP_BUSY;
  			port->vdo_retry = (p0 & ~VDO_CMDT_MASK) |
  				CMDT_INIT;
  			mod_delayed_work(port->wq, &port->vdm_state_machine,
  					 msecs_to_jiffies(PD_T_VDM_BUSY));
  			return;
  		}
  		port->vdm_state = VDM_STATE_DONE;
  	}
  
  	if (PD_VDO_SVDM(p0))
  		rlen = tcpm_pd_svdm(port, payload, cnt, response);
  
  	if (rlen > 0) {
  		tcpm_queue_vdm(port, response[0], &response[1], rlen - 1);
  		mod_delayed_work(port->wq, &port->vdm_state_machine, 0);
  	}
  }
  
  static void tcpm_send_vdm(struct tcpm_port *port, u32 vid, int cmd,
  			  const u32 *data, int count)
  {
  	u32 header;
  
  	if (WARN_ON(count > VDO_MAX_SIZE - 1))
  		count = VDO_MAX_SIZE - 1;
  
  	/* set VDM header with VID & CMD */
  	header = VDO(vid, ((vid & USB_SID_PD) == USB_SID_PD) ?
  			1 : (PD_VDO_CMD(cmd) <= CMD_ATTENTION), cmd);
  	tcpm_queue_vdm(port, header, data, count);
  
  	mod_delayed_work(port->wq, &port->vdm_state_machine, 0);
  }
  
  static unsigned int vdm_ready_timeout(u32 vdm_hdr)
  {
  	unsigned int timeout;
  	int cmd = PD_VDO_CMD(vdm_hdr);
  
  	/* its not a structured VDM command */
  	if (!PD_VDO_SVDM(vdm_hdr))
  		return PD_T_VDM_UNSTRUCTURED;
  
  	switch (PD_VDO_CMDT(vdm_hdr)) {
  	case CMDT_INIT:
  		if (cmd == CMD_ENTER_MODE || cmd == CMD_EXIT_MODE)
  			timeout = PD_T_VDM_WAIT_MODE_E;
  		else
  			timeout = PD_T_VDM_SNDR_RSP;
  		break;
  	default:
  		if (cmd == CMD_ENTER_MODE || cmd == CMD_EXIT_MODE)
  			timeout = PD_T_VDM_E_MODE;
  		else
  			timeout = PD_T_VDM_RCVR_RSP;
  		break;
  	}
  	return timeout;
  }
  
  static void vdm_run_state_machine(struct tcpm_port *port)
  {
  	struct pd_message msg;
  	int i, res;
  
  	switch (port->vdm_state) {
  	case VDM_STATE_READY:
  		/* Only transmit VDM if attached */
  		if (!port->attached) {
  			port->vdm_state = VDM_STATE_ERR_BUSY;
  			break;
  		}
  
  		/*
  		 * if there's traffic or we're not in PDO ready state don't send
  		 * a VDM.
  		 */
  		if (port->state != SRC_READY && port->state != SNK_READY)
  			break;
  
  		/* Prepare and send VDM */
  		memset(&msg, 0, sizeof(msg));
  		msg.header = PD_HEADER_LE(PD_DATA_VENDOR_DEF,
  					  port->pwr_role,
  					  port->data_role,
  					  port->negotiated_rev,
  					  port->message_id, port->vdo_count);
  		for (i = 0; i < port->vdo_count; i++)
  			msg.payload[i] = cpu_to_le32(port->vdo_data[i]);
  		res = tcpm_pd_transmit(port, TCPC_TX_SOP, &msg);
  		if (res < 0) {
  			port->vdm_state = VDM_STATE_ERR_SEND;
  		} else {
  			unsigned long timeout;
  
  			port->vdm_retries = 0;
  			port->vdm_state = VDM_STATE_BUSY;
  			timeout = vdm_ready_timeout(port->vdo_data[0]);
  			mod_delayed_work(port->wq, &port->vdm_state_machine,
  					 timeout);
  		}
  		break;
  	case VDM_STATE_WAIT_RSP_BUSY:
  		port->vdo_data[0] = port->vdo_retry;
  		port->vdo_count = 1;
  		port->vdm_state = VDM_STATE_READY;
  		break;
  	case VDM_STATE_BUSY:
  		port->vdm_state = VDM_STATE_ERR_TMOUT;
  		break;
  	case VDM_STATE_ERR_SEND:
  		/*
  		 * A partner which does not support USB PD will not reply,
  		 * so this is not a fatal error. At the same time, some
  		 * devices may not return GoodCRC under some circumstances,
  		 * so we need to retry.
  		 */
  		if (port->vdm_retries < 3) {
  			tcpm_log(port, "VDM Tx error, retry");
  			port->vdm_retries++;
  			port->vdm_state = VDM_STATE_READY;
  		}
  		break;
  	default:
  		break;
  	}
  }
  
  static void vdm_state_machine_work(struct work_struct *work)
  {
  	struct tcpm_port *port = container_of(work, struct tcpm_port,
  					      vdm_state_machine.work);
  	enum vdm_states prev_state;
  
  	mutex_lock(&port->lock);
  
  	/*
  	 * Continue running as long as the port is not busy and there was
  	 * a state change.
  	 */
  	do {
  		prev_state = port->vdm_state;
  		vdm_run_state_machine(port);
  	} while (port->vdm_state != prev_state &&
  		 port->vdm_state != VDM_STATE_BUSY);
  
  	mutex_unlock(&port->lock);
  }
  
  enum pdo_err {
  	PDO_NO_ERR,
  	PDO_ERR_NO_VSAFE5V,
  	PDO_ERR_VSAFE5V_NOT_FIRST,
  	PDO_ERR_PDO_TYPE_NOT_IN_ORDER,
  	PDO_ERR_FIXED_NOT_SORTED,
  	PDO_ERR_VARIABLE_BATT_NOT_SORTED,
  	PDO_ERR_DUPE_PDO,
  	PDO_ERR_PPS_APDO_NOT_SORTED,
  	PDO_ERR_DUPE_PPS_APDO,
  };
  
  static const char * const pdo_err_msg[] = {
  	[PDO_ERR_NO_VSAFE5V] =
  	" err: source/sink caps should atleast have vSafe5V",
  	[PDO_ERR_VSAFE5V_NOT_FIRST] =
  	" err: vSafe5V Fixed Supply Object Shall always be the first object",
  	[PDO_ERR_PDO_TYPE_NOT_IN_ORDER] =
  	" err: PDOs should be in the following order: Fixed; Battery; Variable",
  	[PDO_ERR_FIXED_NOT_SORTED] =
  	" err: Fixed supply pdos should be in increasing order of their fixed voltage",
  	[PDO_ERR_VARIABLE_BATT_NOT_SORTED] =
  	" err: Variable/Battery supply pdos should be in increasing order of their minimum voltage",
  	[PDO_ERR_DUPE_PDO] =
  	" err: Variable/Batt supply pdos cannot have same min/max voltage",
  	[PDO_ERR_PPS_APDO_NOT_SORTED] =
  	" err: Programmable power supply apdos should be in increasing order of their maximum voltage",
  	[PDO_ERR_DUPE_PPS_APDO] =
  	" err: Programmable power supply apdos cannot have same min/max voltage and max current",
  };
  
  static enum pdo_err tcpm_caps_err(struct tcpm_port *port, const u32 *pdo,
  				  unsigned int nr_pdo)
  {
  	unsigned int i;
  
  	/* Should at least contain vSafe5v */
  	if (nr_pdo < 1)
  		return PDO_ERR_NO_VSAFE5V;
  
  	/* The vSafe5V Fixed Supply Object Shall always be the first object */
  	if (pdo_type(pdo[0]) != PDO_TYPE_FIXED ||
  	    pdo_fixed_voltage(pdo[0]) != VSAFE5V)
  		return PDO_ERR_VSAFE5V_NOT_FIRST;
  
  	for (i = 1; i < nr_pdo; i++) {
  		if (pdo_type(pdo[i]) < pdo_type(pdo[i - 1])) {
  			return PDO_ERR_PDO_TYPE_NOT_IN_ORDER;
  		} else if (pdo_type(pdo[i]) == pdo_type(pdo[i - 1])) {
  			enum pd_pdo_type type = pdo_type(pdo[i]);
  
  			switch (type) {
  			/*
  			 * The remaining Fixed Supply Objects, if
  			 * present, shall be sent in voltage order;
  			 * lowest to highest.
  			 */
  			case PDO_TYPE_FIXED:
  				if (pdo_fixed_voltage(pdo[i]) <=
  				    pdo_fixed_voltage(pdo[i - 1]))
  					return PDO_ERR_FIXED_NOT_SORTED;
  				break;
  			/*
  			 * The Battery Supply Objects and Variable
  			 * supply, if present shall be sent in Minimum
  			 * Voltage order; lowest to highest.
  			 */
  			case PDO_TYPE_VAR:
  			case PDO_TYPE_BATT:
  				if (pdo_min_voltage(pdo[i]) <
  				    pdo_min_voltage(pdo[i - 1]))
  					return PDO_ERR_VARIABLE_BATT_NOT_SORTED;
  				else if ((pdo_min_voltage(pdo[i]) ==
  					  pdo_min_voltage(pdo[i - 1])) &&
  					 (pdo_max_voltage(pdo[i]) ==
  					  pdo_max_voltage(pdo[i - 1])))
  					return PDO_ERR_DUPE_PDO;
  				break;
  			/*
  			 * The Programmable Power Supply APDOs, if present,
  			 * shall be sent in Maximum Voltage order;
  			 * lowest to highest.
  			 */
  			case PDO_TYPE_APDO:
  				if (pdo_apdo_type(pdo[i]) != APDO_TYPE_PPS)
  					break;
  
  				if (pdo_pps_apdo_max_voltage(pdo[i]) <
  				    pdo_pps_apdo_max_voltage(pdo[i - 1]))
  					return PDO_ERR_PPS_APDO_NOT_SORTED;
  				else if (pdo_pps_apdo_min_voltage(pdo[i]) ==
  					  pdo_pps_apdo_min_voltage(pdo[i - 1]) &&
  					 pdo_pps_apdo_max_voltage(pdo[i]) ==
  					  pdo_pps_apdo_max_voltage(pdo[i - 1]) &&
  					 pdo_pps_apdo_max_current(pdo[i]) ==
  					  pdo_pps_apdo_max_current(pdo[i - 1]))
  					return PDO_ERR_DUPE_PPS_APDO;
  				break;
  			default:
  				tcpm_log_force(port, " Unknown pdo type");
  			}
  		}
  	}
  
  	return PDO_NO_ERR;
  }
  
  static int tcpm_validate_caps(struct tcpm_port *port, const u32 *pdo,
  			      unsigned int nr_pdo)
  {
  	enum pdo_err err_index = tcpm_caps_err(port, pdo, nr_pdo);
  
  	if (err_index != PDO_NO_ERR) {
  		tcpm_log_force(port, " %s", pdo_err_msg[err_index]);
  		return -EINVAL;
  	}
  
  	return 0;
  }
  
  static int tcpm_altmode_enter(struct typec_altmode *altmode)
  {
  	struct tcpm_port *port = typec_altmode_get_drvdata(altmode);
  	u32 header;
  
  	mutex_lock(&port->lock);
  	header = VDO(altmode->svid, 1, CMD_ENTER_MODE);
  	header |= VDO_OPOS(altmode->mode);
  
  	tcpm_queue_vdm(port, header, NULL, 0);
  	mod_delayed_work(port->wq, &port->vdm_state_machine, 0);
  	mutex_unlock(&port->lock);
  
  	return 0;
  }
  
  static int tcpm_altmode_exit(struct typec_altmode *altmode)
  {
  	struct tcpm_port *port = typec_altmode_get_drvdata(altmode);
  	u32 header;
  
  	mutex_lock(&port->lock);
  	header = VDO(altmode->svid, 1, CMD_EXIT_MODE);
  	header |= VDO_OPOS(altmode->mode);
  
  	tcpm_queue_vdm(port, header, NULL, 0);
  	mod_delayed_work(port->wq, &port->vdm_state_machine, 0);
  	mutex_unlock(&port->lock);
  
  	return 0;
  }
  
  static int tcpm_altmode_vdm(struct typec_altmode *altmode,
  			    u32 header, const u32 *data, int count)
  {
  	struct tcpm_port *port = typec_altmode_get_drvdata(altmode);
  
  	mutex_lock(&port->lock);
  	tcpm_queue_vdm(port, header, data, count - 1);
  	mod_delayed_work(port->wq, &port->vdm_state_machine, 0);
  	mutex_unlock(&port->lock);
  
  	return 0;
  }
  
  static const struct typec_altmode_ops tcpm_altmode_ops = {
  	.enter = tcpm_altmode_enter,
  	.exit = tcpm_altmode_exit,
  	.vdm = tcpm_altmode_vdm,
  };
  
  /*
   * PD (data, control) command handling functions
   */
  static inline enum tcpm_state ready_state(struct tcpm_port *port)
  {
  	if (port->pwr_role == TYPEC_SOURCE)
  		return SRC_READY;
  	else
  		return SNK_READY;
  }
  
  static int tcpm_pd_send_control(struct tcpm_port *port,
  				enum pd_ctrl_msg_type type);
  
  static void tcpm_handle_alert(struct tcpm_port *port, const __le32 *payload,
  			      int cnt)
  {
  	u32 p0 = le32_to_cpu(payload[0]);
  	unsigned int type = usb_pd_ado_type(p0);
  
  	if (!type) {
  		tcpm_log(port, "Alert message received with no type");
  		return;
  	}
  
  	/* Just handling non-battery alerts for now */
  	if (!(type & USB_PD_ADO_TYPE_BATT_STATUS_CHANGE)) {
  		switch (port->state) {
  		case SRC_READY:
  		case SNK_READY:
  			tcpm_set_state(port, GET_STATUS_SEND, 0);
  			break;
  		default:
  			tcpm_queue_message(port, PD_MSG_CTRL_WAIT);
  			break;
  		}
  	}
  }
  
  static void tcpm_pd_data_request(struct tcpm_port *port,
  				 const struct pd_message *msg)
  {
  	enum pd_data_msg_type type = pd_header_type_le(msg->header);
  	unsigned int cnt = pd_header_cnt_le(msg->header);
  	unsigned int rev = pd_header_rev_le(msg->header);
  	unsigned int i;
  
  	switch (type) {
  	case PD_DATA_SOURCE_CAP:
  		if (port->pwr_role != TYPEC_SINK)
  			break;
  
  		for (i = 0; i < cnt; i++)
  			port->source_caps[i] = le32_to_cpu(msg->payload[i]);
  
  		port->nr_source_caps = cnt;
  
  		tcpm_log_source_caps(port);
  
  		tcpm_validate_caps(port, port->source_caps,
  				   port->nr_source_caps);
  
  		/*
  		 * Adjust revision in subsequent message headers, as required,
  		 * to comply with 6.2.1.1.5 of the USB PD 3.0 spec. We don't
  		 * support Rev 1.0 so just do nothing in that scenario.
  		 */
  		if (rev == PD_REV10)
  			break;
  
  		if (rev < PD_MAX_REV)
  			port->negotiated_rev = rev;
  
  		/*
  		 * This message may be received even if VBUS is not
  		 * present. This is quite unexpected; see USB PD
  		 * specification, sections 8.3.3.6.3.1 and 8.3.3.6.3.2.
  		 * However, at the same time, we must be ready to
  		 * receive this message and respond to it 15ms after
  		 * receiving PS_RDY during power swap operations, no matter
  		 * if VBUS is available or not (USB PD specification,
  		 * section 6.5.9.2).
  		 * So we need to accept the message either way,
  		 * but be prepared to keep waiting for VBUS after it was
  		 * handled.
  		 */
  		tcpm_set_state(port, SNK_NEGOTIATE_CAPABILITIES, 0);
  		break;
  	case PD_DATA_REQUEST:
  		if (port->pwr_role != TYPEC_SOURCE ||
  		    cnt != 1) {
  			tcpm_queue_message(port, PD_MSG_CTRL_REJECT);
  			break;
  		}
  
  		/*
  		 * Adjust revision in subsequent message headers, as required,
  		 * to comply with 6.2.1.1.5 of the USB PD 3.0 spec. We don't
  		 * support Rev 1.0 so just reject in that scenario.
  		 */
  		if (rev == PD_REV10) {
  			tcpm_queue_message(port, PD_MSG_CTRL_REJECT);
  			break;
  		}
  
  		if (rev < PD_MAX_REV)
  			port->negotiated_rev = rev;
  
  		port->sink_request = le32_to_cpu(msg->payload[0]);
  		tcpm_set_state(port, SRC_NEGOTIATE_CAPABILITIES, 0);
  		break;
  	case PD_DATA_SINK_CAP:
  		/* We don't do anything with this at the moment... */
  		for (i = 0; i < cnt; i++)
  			port->sink_caps[i] = le32_to_cpu(msg->payload[i]);
  		port->nr_sink_caps = cnt;
  		break;
  	case PD_DATA_VENDOR_DEF:
  		tcpm_handle_vdm_request(port, msg->payload, cnt);
  		break;
  	case PD_DATA_BIST:
  		if (port->state == SRC_READY || port->state == SNK_READY) {
  			port->bist_request = le32_to_cpu(msg->payload[0]);
  			tcpm_set_state(port, BIST_RX, 0);
  		}
  		break;
  	case PD_DATA_ALERT:
  		tcpm_handle_alert(port, msg->payload, cnt);
  		break;
  	case PD_DATA_BATT_STATUS:
  	case PD_DATA_GET_COUNTRY_INFO:
  		/* Currently unsupported */
  		tcpm_queue_message(port, PD_MSG_CTRL_NOT_SUPP);
  		break;
  	default:
  		tcpm_log(port, "Unhandled data message type %#x", type);
  		break;
  	}
  }
  
  static void tcpm_pps_complete(struct tcpm_port *port, int result)
  {
  	if (port->pps_pending) {
  		port->pps_status = result;
  		port->pps_pending = false;
  		complete(&port->pps_complete);
  	}
  }
  
  static void tcpm_pd_ctrl_request(struct tcpm_port *port,
  				 const struct pd_message *msg)
  {
  	enum pd_ctrl_msg_type type = pd_header_type_le(msg->header);
  	enum tcpm_state next_state;
  
  	switch (type) {
  	case PD_CTRL_GOOD_CRC:
  	case PD_CTRL_PING:
  		break;
  	case PD_CTRL_GET_SOURCE_CAP:
  		switch (port->state) {
  		case SRC_READY:
  		case SNK_READY:
  			tcpm_queue_message(port, PD_MSG_DATA_SOURCE_CAP);
  			break;
  		default:
  			tcpm_queue_message(port, PD_MSG_CTRL_REJECT);
  			break;
  		}
  		break;
  	case PD_CTRL_GET_SINK_CAP:
  		switch (port->state) {
  		case SRC_READY:
  		case SNK_READY:
  			tcpm_queue_message(port, PD_MSG_DATA_SINK_CAP);
  			break;
  		default:
  			tcpm_queue_message(port, PD_MSG_CTRL_REJECT);
  			break;
  		}
  		break;
  	case PD_CTRL_GOTO_MIN:
  		break;
  	case PD_CTRL_PS_RDY:
  		switch (port->state) {
  		case SNK_TRANSITION_SINK:
  			if (port->vbus_present) {
  				tcpm_set_current_limit(port,
  						       port->current_limit,
  						       port->supply_voltage);
  				port->explicit_contract = true;
  				tcpm_set_state(port, SNK_READY, 0);
  			} else {
  				/*
  				 * Seen after power swap. Keep waiting for VBUS
  				 * in a transitional state.
  				 */
  				tcpm_set_state(port,
  					       SNK_TRANSITION_SINK_VBUS, 0);
  			}
  			break;
  		case PR_SWAP_SRC_SNK_SOURCE_OFF_CC_DEBOUNCED:
  			tcpm_set_state(port, PR_SWAP_SRC_SNK_SINK_ON, 0);
  			break;
  		case PR_SWAP_SNK_SRC_SINK_OFF:
  			tcpm_set_state(port, PR_SWAP_SNK_SRC_SOURCE_ON, 0);
  			break;
  		case VCONN_SWAP_WAIT_FOR_VCONN:
  			tcpm_set_state(port, VCONN_SWAP_TURN_OFF_VCONN, 0);
  			break;
  		default:
  			break;
  		}
  		break;
  	case PD_CTRL_REJECT:
  	case PD_CTRL_WAIT:
  	case PD_CTRL_NOT_SUPP:
  		switch (port->state) {
  		case SNK_NEGOTIATE_CAPABILITIES:
  			/* USB PD specification, Figure 8-43 */
  			if (port->explicit_contract)
  				next_state = SNK_READY;
  			else
  				next_state = SNK_WAIT_CAPABILITIES;
  			tcpm_set_state(port, next_state, 0);
  			break;
  		case SNK_NEGOTIATE_PPS_CAPABILITIES:
  			/* Revert data back from any requested PPS updates */
  			port->pps_data.out_volt = port->supply_voltage;
  			port->pps_data.op_curr = port->current_limit;
  			port->pps_status = (type == PD_CTRL_WAIT ?
  					    -EAGAIN : -EOPNOTSUPP);
  			tcpm_set_state(port, SNK_READY, 0);
  			break;
  		case DR_SWAP_SEND:
  			port->swap_status = (type == PD_CTRL_WAIT ?
  					     -EAGAIN : -EOPNOTSUPP);
  			tcpm_set_state(port, DR_SWAP_CANCEL, 0);
  			break;
  		case PR_SWAP_SEND:
  			port->swap_status = (type == PD_CTRL_WAIT ?
  					     -EAGAIN : -EOPNOTSUPP);
  			tcpm_set_state(port, PR_SWAP_CANCEL, 0);
  			break;
  		case VCONN_SWAP_SEND:
  			port->swap_status = (type == PD_CTRL_WAIT ?
  					     -EAGAIN : -EOPNOTSUPP);
  			tcpm_set_state(port, VCONN_SWAP_CANCEL, 0);
  			break;
  		default:
  			break;
  		}
  		break;
  	case PD_CTRL_ACCEPT:
  		switch (port->state) {
  		case SNK_NEGOTIATE_CAPABILITIES:
  			port->pps_data.active = false;
  			tcpm_set_state(port, SNK_TRANSITION_SINK, 0);
  			break;
  		case SNK_NEGOTIATE_PPS_CAPABILITIES:
  			port->pps_data.active = true;
  			port->supply_voltage = port->pps_data.out_volt;
  			port->current_limit = port->pps_data.op_curr;
  			tcpm_set_state(port, SNK_TRANSITION_SINK, 0);
  			break;
  		case SOFT_RESET_SEND:
  			port->message_id = 0;
  			port->rx_msgid = -1;
  			if (port->pwr_role == TYPEC_SOURCE)
  				next_state = SRC_SEND_CAPABILITIES;
  			else
  				next_state = SNK_WAIT_CAPABILITIES;
  			tcpm_set_state(port, next_state, 0);
  			break;
  		case DR_SWAP_SEND:
  			tcpm_set_state(port, DR_SWAP_CHANGE_DR, 0);
  			break;
  		case PR_SWAP_SEND:
  			tcpm_set_state(port, PR_SWAP_START, 0);
  			break;
  		case VCONN_SWAP_SEND:
  			tcpm_set_state(port, VCONN_SWAP_START, 0);
  			break;
  		default:
  			break;
  		}
  		break;
  	case PD_CTRL_SOFT_RESET:
  		tcpm_set_state(port, SOFT_RESET, 0);
  		break;
  	case PD_CTRL_DR_SWAP:
  		if (port->port_type != TYPEC_PORT_DRP) {
  			tcpm_queue_message(port, PD_MSG_CTRL_REJECT);
  			break;
  		}
  		/*
  		 * XXX
  		 * 6.3.9: If an alternate mode is active, a request to swap
  		 * alternate modes shall trigger a port reset.
  		 */
  		switch (port->state) {
  		case SRC_READY:
  		case SNK_READY:
  			tcpm_set_state(port, DR_SWAP_ACCEPT, 0);
  			break;
  		default:
  			tcpm_queue_message(port, PD_MSG_CTRL_WAIT);
  			break;
  		}
  		break;
  	case PD_CTRL_PR_SWAP:
  		if (port->port_type != TYPEC_PORT_DRP) {
  			tcpm_queue_message(port, PD_MSG_CTRL_REJECT);
  			break;
  		}
  		switch (port->state) {
  		case SRC_READY:
  		case SNK_READY:
  			tcpm_set_state(port, PR_SWAP_ACCEPT, 0);
  			break;
  		default:
  			tcpm_queue_message(port, PD_MSG_CTRL_WAIT);
  			break;
  		}
  		break;
  	case PD_CTRL_VCONN_SWAP:
  		switch (port->state) {
  		case SRC_READY:
  		case SNK_READY:
  			tcpm_set_state(port, VCONN_SWAP_ACCEPT, 0);
  			break;
  		default:
  			tcpm_queue_message(port, PD_MSG_CTRL_WAIT);
  			break;
  		}
  		break;
  	case PD_CTRL_GET_SOURCE_CAP_EXT:
  	case PD_CTRL_GET_STATUS:
  	case PD_CTRL_FR_SWAP:
  	case PD_CTRL_GET_PPS_STATUS:
  	case PD_CTRL_GET_COUNTRY_CODES:
  		/* Currently not supported */
  		tcpm_queue_message(port, PD_MSG_CTRL_NOT_SUPP);
  		break;
  	default:
  		tcpm_log(port, "Unhandled ctrl message type %#x", type);
  		break;
  	}
  }
  
  static void tcpm_pd_ext_msg_request(struct tcpm_port *port,
  				    const struct pd_message *msg)
  {
  	enum pd_ext_msg_type type = pd_header_type_le(msg->header);
  	unsigned int data_size = pd_ext_header_data_size_le(msg->ext_msg.header);
  
  	if (!(msg->ext_msg.header & PD_EXT_HDR_CHUNKED)) {
  		tcpm_log(port, "Unchunked extended messages unsupported");
  		return;
  	}
  
  	if (data_size > PD_EXT_MAX_CHUNK_DATA) {
  		tcpm_log(port, "Chunk handling not yet supported");
  		return;
  	}
  
  	switch (type) {
  	case PD_EXT_STATUS:
  		/*
  		 * If PPS related events raised then get PPS status to clear
  		 * (see USB PD 3.0 Spec, 6.5.2.4)
  		 */
  		if (msg->ext_msg.data[USB_PD_EXT_SDB_EVENT_FLAGS] &
  		    USB_PD_EXT_SDB_PPS_EVENTS)
  			tcpm_set_state(port, GET_PPS_STATUS_SEND, 0);
  		else
  			tcpm_set_state(port, ready_state(port), 0);
  		break;
  	case PD_EXT_PPS_STATUS:
  		/*
  		 * For now the PPS status message is used to clear events
  		 * and nothing more.
  		 */
  		tcpm_set_state(port, ready_state(port), 0);
  		break;
  	case PD_EXT_SOURCE_CAP_EXT:
  	case PD_EXT_GET_BATT_CAP:
  	case PD_EXT_GET_BATT_STATUS:
  	case PD_EXT_BATT_CAP:
  	case PD_EXT_GET_MANUFACTURER_INFO:
  	case PD_EXT_MANUFACTURER_INFO:
  	case PD_EXT_SECURITY_REQUEST:
  	case PD_EXT_SECURITY_RESPONSE:
  	case PD_EXT_FW_UPDATE_REQUEST:
  	case PD_EXT_FW_UPDATE_RESPONSE:
  	case PD_EXT_COUNTRY_INFO:
  	case PD_EXT_COUNTRY_CODES:
  		tcpm_queue_message(port, PD_MSG_CTRL_NOT_SUPP);
  		break;
  	default:
  		tcpm_log(port, "Unhandled extended message type %#x", type);
  		break;
  	}
  }
  
  static void tcpm_pd_rx_handler(struct work_struct *work)
  {
  	struct pd_rx_event *event = container_of(work,
  						 struct pd_rx_event, work);
  	const struct pd_message *msg = &event->msg;
  	unsigned int cnt = pd_header_cnt_le(msg->header);
  	struct tcpm_port *port = event->port;
  
  	mutex_lock(&port->lock);
  
  	tcpm_log(port, "PD RX, header: %#x [%d]", le16_to_cpu(msg->header),
  		 port->attached);
  
  	if (port->attached) {
  		enum pd_ctrl_msg_type type = pd_header_type_le(msg->header);
  		unsigned int msgid = pd_header_msgid_le(msg->header);
  
  		/*
  		 * USB PD standard, 6.6.1.2:
  		 * "... if MessageID value in a received Message is the
  		 * same as the stored value, the receiver shall return a
  		 * GoodCRC Message with that MessageID value and drop
  		 * the Message (this is a retry of an already received
  		 * Message). Note: this shall not apply to the Soft_Reset
  		 * Message which always has a MessageID value of zero."
  		 */
  		if (msgid == port->rx_msgid && type != PD_CTRL_SOFT_RESET)
  			goto done;
  		port->rx_msgid = msgid;
  
  		/*
  		 * If both ends believe to be DFP/host, we have a data role
  		 * mismatch.
  		 */
  		if (!!(le16_to_cpu(msg->header) & PD_HEADER_DATA_ROLE) ==
  		    (port->data_role == TYPEC_HOST)) {
  			tcpm_log(port,
  				 "Data role mismatch, initiating error recovery");
  			tcpm_set_state(port, ERROR_RECOVERY, 0);
  		} else {
  			if (msg->header & PD_HEADER_EXT_HDR)
  				tcpm_pd_ext_msg_request(port, msg);
  			else if (cnt)
  				tcpm_pd_data_request(port, msg);
  			else
  				tcpm_pd_ctrl_request(port, msg);
  		}
  	}
  
  done:
  	mutex_unlock(&port->lock);
  	kfree(event);
  }
  
  void tcpm_pd_receive(struct tcpm_port *port, const struct pd_message *msg)
  {
  	struct pd_rx_event *event;
  
  	event = kzalloc(sizeof(*event), GFP_ATOMIC);
  	if (!event)
  		return;
  
  	INIT_WORK(&event->work, tcpm_pd_rx_handler);
  	event->port = port;
  	memcpy(&event->msg, msg, sizeof(*msg));
  	queue_work(port->wq, &event->work);
  }
  EXPORT_SYMBOL_GPL(tcpm_pd_receive);
  
  static int tcpm_pd_send_control(struct tcpm_port *port,
  				enum pd_ctrl_msg_type type)
  {
  	struct pd_message msg;
  
  	memset(&msg, 0, sizeof(msg));
  	msg.header = PD_HEADER_LE(type, port->pwr_role,
  				  port->data_role,
  				  port->negotiated_rev,
  				  port->message_id, 0);
  
  	return tcpm_pd_transmit(port, TCPC_TX_SOP, &msg);
  }
  
  /*
   * Send queued message without affecting state.
   * Return true if state machine should go back to sleep,
   * false otherwise.
   */
  static bool tcpm_send_queued_message(struct tcpm_port *port)
  {
  	enum pd_msg_request queued_message;
  
  	do {
  		queued_message = port->queued_message;
  		port->queued_message = PD_MSG_NONE;
  
  		switch (queued_message) {
  		case PD_MSG_CTRL_WAIT:
  			tcpm_pd_send_control(port, PD_CTRL_WAIT);
  			break;
  		case PD_MSG_CTRL_REJECT:
  			tcpm_pd_send_control(port, PD_CTRL_REJECT);
  			break;
  		case PD_MSG_CTRL_NOT_SUPP:
  			tcpm_pd_send_control(port, PD_CTRL_NOT_SUPP);
  			break;
  		case PD_MSG_DATA_SINK_CAP:
  			tcpm_pd_send_sink_caps(port);
  			break;
  		case PD_MSG_DATA_SOURCE_CAP:
  			tcpm_pd_send_source_caps(port);
  			break;
  		default:
  			break;
  		}
  	} while (port->queued_message != PD_MSG_NONE);
  
  	if (port->delayed_state != INVALID_STATE) {
  		if (time_is_after_jiffies(port->delayed_runtime)) {
  			mod_delayed_work(port->wq, &port->state_machine,
  					 port->delayed_runtime - jiffies);
  			return true;
  		}
  		port->delayed_state = INVALID_STATE;
  	}
  	return false;
  }
  
  static int tcpm_pd_check_request(struct tcpm_port *port)
  {
  	u32 pdo, rdo = port->sink_request;
  	unsigned int max, op, pdo_max, index;
  	enum pd_pdo_type type;
  
  	index = rdo_index(rdo);
  	if (!index || index > port->nr_src_pdo)
  		return -EINVAL;
  
  	pdo = port->src_pdo[index - 1];
  	type = pdo_type(pdo);
  	switch (type) {
  	case PDO_TYPE_FIXED:
  	case PDO_TYPE_VAR:
  		max = rdo_max_current(rdo);
  		op = rdo_op_current(rdo);
  		pdo_max = pdo_max_current(pdo);
  
  		if (op > pdo_max)
  			return -EINVAL;
  		if (max > pdo_max && !(rdo & RDO_CAP_MISMATCH))
  			return -EINVAL;
  
  		if (type == PDO_TYPE_FIXED)
  			tcpm_log(port,
  				 "Requested %u mV, %u mA for %u / %u mA",
  				 pdo_fixed_voltage(pdo), pdo_max, op, max);
  		else
  			tcpm_log(port,
  				 "Requested %u -> %u mV, %u mA for %u / %u mA",
  				 pdo_min_voltage(pdo), pdo_max_voltage(pdo),
  				 pdo_max, op, max);
  		break;
  	case PDO_TYPE_BATT:
  		max = rdo_max_power(rdo);
  		op = rdo_op_power(rdo);
  		pdo_max = pdo_max_power(pdo);
  
  		if (op > pdo_max)
  			return -EINVAL;
  		if (max > pdo_max && !(rdo & RDO_CAP_MISMATCH))
  			return -EINVAL;
  		tcpm_log(port,
  			 "Requested %u -> %u mV, %u mW for %u / %u mW",
  			 pdo_min_voltage(pdo), pdo_max_voltage(pdo),
  			 pdo_max, op, max);
  		break;
  	default:
  		return -EINVAL;
  	}
  
  	port->op_vsafe5v = index == 1;
  
  	return 0;
  }
  
  #define min_power(x, y) min(pdo_max_power(x), pdo_max_power(y))
  #define min_current(x, y) min(pdo_max_current(x), pdo_max_current(y))
  
  static int tcpm_pd_select_pdo(struct tcpm_port *port, int *sink_pdo,
  			      int *src_pdo)
  {
  	unsigned int i, j, max_src_mv = 0, min_src_mv = 0, max_mw = 0,
  		     max_mv = 0, src_mw = 0, src_ma = 0, max_snk_mv = 0,
  		     min_snk_mv = 0;
  	int ret = -EINVAL;
  
  	port->pps_data.supported = false;
  	port->usb_type = POWER_SUPPLY_USB_TYPE_PD;
  
  	/*
  	 * Select the source PDO providing the most power which has a
  	 * matchig sink cap.
  	 */
  	for (i = 0; i < port->nr_source_caps; i++) {
  		u32 pdo = port->source_caps[i];
  		enum pd_pdo_type type = pdo_type(pdo);
  
  		switch (type) {
  		case PDO_TYPE_FIXED:
  			max_src_mv = pdo_fixed_voltage(pdo);
  			min_src_mv = max_src_mv;
  			break;
  		case PDO_TYPE_BATT:
  		case PDO_TYPE_VAR:
  			max_src_mv = pdo_max_voltage(pdo);
  			min_src_mv = pdo_min_voltage(pdo);
  			break;
  		case PDO_TYPE_APDO:
  			if (pdo_apdo_type(pdo) == APDO_TYPE_PPS) {
  				port->pps_data.supported = true;
  				port->usb_type =
  					POWER_SUPPLY_USB_TYPE_PD_PPS;
  			}
  			continue;
  		default:
  			tcpm_log(port, "Invalid source PDO type, ignoring");
  			continue;
  		}
  
  		switch (type) {
  		case PDO_TYPE_FIXED:
  		case PDO_TYPE_VAR:
  			src_ma = pdo_max_current(pdo);
  			src_mw = src_ma * min_src_mv / 1000;
  			break;
  		case PDO_TYPE_BATT:
  			src_mw = pdo_max_power(pdo);
  			break;
  		case PDO_TYPE_APDO:
  			continue;
  		default:
  			tcpm_log(port, "Invalid source PDO type, ignoring");
  			continue;
  		}
  
  		for (j = 0; j < port->nr_snk_pdo; j++) {
  			pdo = port->snk_pdo[j];
  
  			switch (pdo_type(pdo)) {
  			case PDO_TYPE_FIXED:
  				max_snk_mv = pdo_fixed_voltage(pdo);
  				min_snk_mv = max_snk_mv;
  				break;
  			case PDO_TYPE_BATT:
  			case PDO_TYPE_VAR:
  				max_snk_mv = pdo_max_voltage(pdo);
  				min_snk_mv = pdo_min_voltage(pdo);
  				break;
  			case PDO_TYPE_APDO:
  				continue;
  			default:
  				tcpm_log(port, "Invalid sink PDO type, ignoring");
  				continue;
  			}
  
  			if (max_src_mv <= max_snk_mv &&
  				min_src_mv >= min_snk_mv) {
  				/* Prefer higher voltages if available */
  				if ((src_mw == max_mw && min_src_mv > max_mv) ||
  							src_mw > max_mw) {
  					*src_pdo = i;
  					*sink_pdo = j;
  					max_mw = src_mw;
  					max_mv = min_src_mv;
  					ret = 0;
  				}
  			}
  		}
  	}
  
  	return ret;
  }
  
  #define min_pps_apdo_current(x, y)	\
  	min(pdo_pps_apdo_max_current(x), pdo_pps_apdo_max_current(y))
  
  static unsigned int tcpm_pd_select_pps_apdo(struct tcpm_port *port)
  {
  	unsigned int i, j, max_mw = 0, max_mv = 0;
  	unsigned int min_src_mv, max_src_mv, src_ma, src_mw;
  	unsigned int min_snk_mv, max_snk_mv;
  	unsigned int max_op_mv;
  	u32 pdo, src, snk;
  	unsigned int src_pdo = 0, snk_pdo = 0;
  
  	/*
  	 * Select the source PPS APDO providing the most power while staying
  	 * within the board's limits. We skip the first PDO as this is always
  	 * 5V 3A.
  	 */
  	for (i = 1; i < port->nr_source_caps; ++i) {
  		pdo = port->source_caps[i];
  
  		switch (pdo_type(pdo)) {
  		case PDO_TYPE_APDO:
  			if (pdo_apdo_type(pdo) != APDO_TYPE_PPS) {
  				tcpm_log(port, "Not PPS APDO (source), ignoring");
  				continue;
  			}
  
  			min_src_mv = pdo_pps_apdo_min_voltage(pdo);
  			max_src_mv = pdo_pps_apdo_max_voltage(pdo);
  			src_ma = pdo_pps_apdo_max_current(pdo);
  			src_mw = (src_ma * max_src_mv) / 1000;
  
  			/*
  			 * Now search through the sink PDOs to find a matching
  			 * PPS APDO. Again skip the first sink PDO as this will
  			 * always be 5V 3A.
  			 */
  			for (j = 1; j < port->nr_snk_pdo; j++) {
  				pdo = port->snk_pdo[j];
  
  				switch (pdo_type(pdo)) {
  				case PDO_TYPE_APDO:
  					if (pdo_apdo_type(pdo) != APDO_TYPE_PPS) {
  						tcpm_log(port,
  							 "Not PPS APDO (sink), ignoring");
  						continue;
  					}
  
  					min_snk_mv =
  						pdo_pps_apdo_min_voltage(pdo);
  					max_snk_mv =
  						pdo_pps_apdo_max_voltage(pdo);
  					break;
  				default:
  					tcpm_log(port,
  						 "Not APDO type (sink), ignoring");
  					continue;
  				}
  
  				if (min_src_mv <= max_snk_mv &&
  				    max_src_mv >= min_snk_mv) {
  					max_op_mv = min(max_src_mv, max_snk_mv);
  					src_mw = (max_op_mv * src_ma) / 1000;
  					/* Prefer higher voltages if available */
  					if ((src_mw == max_mw &&
  					     max_op_mv > max_mv) ||
  					    src_mw > max_mw) {
  						src_pdo = i;
  						snk_pdo = j;
  						max_mw = src_mw;
  						max_mv = max_op_mv;
  					}
  				}
  			}
  
  			break;
  		default:
  			tcpm_log(port, "Not APDO type (source), ignoring");
  			continue;
  		}
  	}
  
  	if (src_pdo) {
  		src = port->source_caps[src_pdo];
  		snk = port->snk_pdo[snk_pdo];
  
  		port->pps_data.min_volt = max(pdo_pps_apdo_min_voltage(src),
  					      pdo_pps_apdo_min_voltage(snk));
  		port->pps_data.max_volt = min(pdo_pps_apdo_max_voltage(src),
  					      pdo_pps_apdo_max_voltage(snk));
  		port->pps_data.max_curr = min_pps_apdo_current(src, snk);
  		port->pps_data.out_volt = min(port->pps_data.max_volt,
  					      max(port->pps_data.min_volt,
  						  port->pps_data.out_volt));
  		port->pps_data.op_curr = min(port->pps_data.max_curr,
  					     port->pps_data.op_curr);
  	}
  
  	return src_pdo;
  }
  
  static int tcpm_pd_build_request(struct tcpm_port *port, u32 *rdo)
  {
  	unsigned int mv, ma, mw, flags;
  	unsigned int max_ma, max_mw;
  	enum pd_pdo_type type;
  	u32 pdo, matching_snk_pdo;
  	int src_pdo_index = 0;
  	int snk_pdo_index = 0;
  	int ret;
  
  	ret = tcpm_pd_select_pdo(port, &snk_pdo_index, &src_pdo_index);
  	if (ret < 0)
  		return ret;
  
  	pdo = port->source_caps[src_pdo_index];
  	matching_snk_pdo = port->snk_pdo[snk_pdo_index];
  	type = pdo_type(pdo);
  
  	switch (type) {
  	case PDO_TYPE_FIXED:
  		mv = pdo_fixed_voltage(pdo);
  		break;
  	case PDO_TYPE_BATT:
  	case PDO_TYPE_VAR:
  		mv = pdo_min_voltage(pdo);
  		break;
  	default:
  		tcpm_log(port, "Invalid PDO selected!");
  		return -EINVAL;
  	}
  
  	/* Select maximum available current within the sink pdo's limit */
  	if (type == PDO_TYPE_BATT) {
  		mw = min_power(pdo, matching_snk_pdo);
  		ma = 1000 * mw / mv;
  	} else {
  		ma = min_current(pdo, matching_snk_pdo);
  		mw = ma * mv / 1000;
  	}
  
  	flags = RDO_USB_COMM | RDO_NO_SUSPEND;
  
  	/* Set mismatch bit if offered power is less than operating power */
  	max_ma = ma;
  	max_mw = mw;
  	if (mw < port->operating_snk_mw) {
  		flags |= RDO_CAP_MISMATCH;
  		if (type == PDO_TYPE_BATT &&
  		    (pdo_max_power(matching_snk_pdo) > pdo_max_power(pdo)))
  			max_mw = pdo_max_power(matching_snk_pdo);
  		else if (pdo_max_current(matching_snk_pdo) >
  			 pdo_max_current(pdo))
  			max_ma = pdo_max_current(matching_snk_pdo);
  	}
  
  	tcpm_log(port, "cc=%d cc1=%d cc2=%d vbus=%d vconn=%s polarity=%d",
  		 port->cc_req, port->cc1, port->cc2, port->vbus_source,
  		 port->vconn_role == TYPEC_SOURCE ? "source" : "sink",
  		 port->polarity);
  
  	if (type == PDO_TYPE_BATT) {
  		*rdo = RDO_BATT(src_pdo_index + 1, mw, max_mw, flags);
  
  		tcpm_log(port, "Requesting PDO %d: %u mV, %u mW%s",
  			 src_pdo_index, mv, mw,
  			 flags & RDO_CAP_MISMATCH ? " [mismatch]" : "");
  	} else {
  		*rdo = RDO_FIXED(src_pdo_index + 1, ma, max_ma, flags);
  
  		tcpm_log(port, "Requesting PDO %d: %u mV, %u mA%s",
  			 src_pdo_index, mv, ma,
  			 flags & RDO_CAP_MISMATCH ? " [mismatch]" : "");
  	}
  
  	port->current_limit = ma;
  	port->supply_voltage = mv;
  
  	return 0;
  }
  
  static int tcpm_pd_send_request(struct tcpm_port *port)
  {
  	struct pd_message msg;
  	int ret;
  	u32 rdo;
  
  	ret = tcpm_pd_build_request(port, &rdo);
  	if (ret < 0)
  		return ret;
  
  	memset(&msg, 0, sizeof(msg));
  	msg.header = PD_HEADER_LE(PD_DATA_REQUEST,
  				  port->pwr_role,
  				  port->data_role,
  				  port->negotiated_rev,
  				  port->message_id, 1);
  	msg.payload[0] = cpu_to_le32(rdo);
  
  	return tcpm_pd_transmit(port, TCPC_TX_SOP, &msg);
  }
  
  static int tcpm_pd_build_pps_request(struct tcpm_port *port, u32 *rdo)
  {
  	unsigned int out_mv, op_ma, op_mw, max_mv, max_ma, flags;
  	enum pd_pdo_type type;
  	unsigned int src_pdo_index;
  	u32 pdo;
  
  	src_pdo_index = tcpm_pd_select_pps_apdo(port);
  	if (!src_pdo_index)
  		return -EOPNOTSUPP;
  
  	pdo = port->source_caps[src_pdo_index];
  	type = pdo_type(pdo);
  
  	switch (type) {
  	case PDO_TYPE_APDO:
  		if (pdo_apdo_type(pdo) != APDO_TYPE_PPS) {
  			tcpm_log(port, "Invalid APDO selected!");
  			return -EINVAL;
  		}
  		max_mv = port->pps_data.max_volt;
  		max_ma = port->pps_data.max_curr;
  		out_mv = port->pps_data.out_volt;
  		op_ma = port->pps_data.op_curr;
  		break;
  	default:
  		tcpm_log(port, "Invalid PDO selected!");
  		return -EINVAL;
  	}
  
  	flags = RDO_USB_COMM | RDO_NO_SUSPEND;
  
  	op_mw = (op_ma * out_mv) / 1000;
  	if (op_mw < port->operating_snk_mw) {
  		/*
  		 * Try raising current to meet power needs. If that's not enough
  		 * then try upping the voltage. If that's still not enough
  		 * then we've obviously chosen a PPS APDO which really isn't
  		 * suitable so abandon ship.
  		 */
  		op_ma = (port->operating_snk_mw * 1000) / out_mv;
  		if ((port->operating_snk_mw * 1000) % out_mv)
  			++op_ma;
  		op_ma += RDO_PROG_CURR_MA_STEP - (op_ma % RDO_PROG_CURR_MA_STEP);
  
  		if (op_ma > max_ma) {
  			op_ma = max_ma;
  			out_mv = (port->operating_snk_mw * 1000) / op_ma;
  			if ((port->operating_snk_mw * 1000) % op_ma)
  				++out_mv;
  			out_mv += RDO_PROG_VOLT_MV_STEP -
  				  (out_mv % RDO_PROG_VOLT_MV_STEP);
  
  			if (out_mv > max_mv) {
  				tcpm_log(port, "Invalid PPS APDO selected!");
  				return -EINVAL;
  			}
  		}
  	}
  
  	tcpm_log(port, "cc=%d cc1=%d cc2=%d vbus=%d vconn=%s polarity=%d",
  		 port->cc_req, port->cc1, port->cc2, port->vbus_source,
  		 port->vconn_role == TYPEC_SOURCE ? "source" : "sink",
  		 port->polarity);
  
  	*rdo = RDO_PROG(src_pdo_index + 1, out_mv, op_ma, flags);
  
  	tcpm_log(port, "Requesting APDO %d: %u mV, %u mA",
  		 src_pdo_index, out_mv, op_ma);
  
  	port->pps_data.op_curr = op_ma;
  	port->pps_data.out_volt = out_mv;
  
  	return 0;
  }
  
  static int tcpm_pd_send_pps_request(struct tcpm_port *port)
  {
  	struct pd_message msg;
  	int ret;
  	u32 rdo;
  
  	ret = tcpm_pd_build_pps_request(port, &rdo);
  	if (ret < 0)
  		return ret;
  
  	memset(&msg, 0, sizeof(msg));
  	msg.header = PD_HEADER_LE(PD_DATA_REQUEST,
  				  port->pwr_role,
  				  port->data_role,
  				  port->negotiated_rev,
  				  port->message_id, 1);
  	msg.payload[0] = cpu_to_le32(rdo);
  
  	return tcpm_pd_transmit(port, TCPC_TX_SOP, &msg);
  }
  
  static int tcpm_set_vbus(struct tcpm_port *port, bool enable)
  {
  	int ret;
  
  	if (enable && port->vbus_charge)
  		return -EINVAL;
  
  	tcpm_log(port, "vbus:=%d charge=%d", enable, port->vbus_charge);
  
  	ret = port->tcpc->set_vbus(port->tcpc, enable, port->vbus_charge);
  	if (ret < 0)
  		return ret;
  
  	port->vbus_source = enable;
  	return 0;
  }
  
  static int tcpm_set_charge(struct tcpm_port *port, bool charge)
  {
  	int ret;
  
  	if (charge && port->vbus_source)
  		return -EINVAL;
  
  	if (charge != port->vbus_charge) {
  		tcpm_log(port, "vbus=%d charge:=%d", port->vbus_source, charge);
  		ret = port->tcpc->set_vbus(port->tcpc, port->vbus_source,
  					   charge);
  		if (ret < 0)
  			return ret;
  	}
  	port->vbus_charge = charge;
  	return 0;
  }
  
  static bool tcpm_start_toggling(struct tcpm_port *port, enum typec_cc_status cc)
  {
  	int ret;
  
  	if (!port->tcpc->start_toggling)
  		return false;
  
  	tcpm_log_force(port, "Start toggling");
  	ret = port->tcpc->start_toggling(port->tcpc, port->port_type, cc);
  	return ret == 0;
  }
  
  static void tcpm_set_cc(struct tcpm_port *port, enum typec_cc_status cc)
  {
  	tcpm_log(port, "cc:=%d", cc);
  	port->cc_req = cc;
  	port->tcpc->set_cc(port->tcpc, cc);
  }
  
  static int tcpm_init_vbus(struct tcpm_port *port)
  {
  	int ret;
  
  	ret = port->tcpc->set_vbus(port->tcpc, false, false);
  	port->vbus_source = false;
  	port->vbus_charge = false;
  	return ret;
  }
  
  static int tcpm_init_vconn(struct tcpm_port *port)
  {
  	int ret;
  
  	ret = port->tcpc->set_vconn(port->tcpc, false);
  	port->vconn_role = TYPEC_SINK;
  	return ret;
  }
  
  static void tcpm_typec_connect(struct tcpm_port *port)
  {
  	if (!port->connected) {
  		/* Make sure we don't report stale identity information */
  		memset(&port->partner_ident, 0, sizeof(port->partner_ident));
  		port->partner_desc.usb_pd = port->pd_capable;
  		if (tcpm_port_is_debug(port))
  			port->partner_desc.accessory = TYPEC_ACCESSORY_DEBUG;
  		else if (tcpm_port_is_audio(port))
  			port->partner_desc.accessory = TYPEC_ACCESSORY_AUDIO;
  		else
  			port->partner_desc.accessory = TYPEC_ACCESSORY_NONE;
  		port->partner = typec_register_partner(port->typec_port,
  						       &port->partner_desc);
  		port->connected = true;
  	}
  }
  
  static int tcpm_src_attach(struct tcpm_port *port)
  {
  	enum typec_cc_polarity polarity =
  				port->cc2 == TYPEC_CC_RD ? TYPEC_POLARITY_CC2
  							 : TYPEC_POLARITY_CC1;
  	int ret;
  
  	if (port->attached)
  		return 0;
  
  	ret = tcpm_set_polarity(port, polarity);
  	if (ret < 0)
  		return ret;
  
  	ret = tcpm_set_roles(port, true, TYPEC_SOURCE, TYPEC_HOST);
  	if (ret < 0)
  		return ret;
  
  	ret = port->tcpc->set_pd_rx(port->tcpc, true);
  	if (ret < 0)
  		goto out_disable_mux;
  
  	/*
  	 * USB Type-C specification, version 1.2,
  	 * chapter 4.5.2.2.8.1 (Attached.SRC Requirements)
  	 * Enable VCONN only if the non-RD port is set to RA.
  	 */
  	if ((polarity == TYPEC_POLARITY_CC1 && port->cc2 == TYPEC_CC_RA) ||
  	    (polarity == TYPEC_POLARITY_CC2 && port->cc1 == TYPEC_CC_RA)) {
  		ret = tcpm_set_vconn(port, true);
  		if (ret < 0)
  			goto out_disable_pd;
  	}
  
  	ret = tcpm_set_vbus(port, true);
  	if (ret < 0)
  		goto out_disable_vconn;
  
  	port->pd_capable = false;
  
  	port->partner = NULL;
  
  	port->attached = true;
  	port->send_discover = true;
  
  	return 0;
  
  out_disable_vconn:
  	tcpm_set_vconn(port, false);
  out_disable_pd:
  	port->tcpc->set_pd_rx(port->tcpc, false);
  out_disable_mux:
  	tcpm_mux_set(port, TYPEC_STATE_SAFE, USB_ROLE_NONE,
  		     TYPEC_ORIENTATION_NONE);
  	return ret;
  }
  
  static void tcpm_typec_disconnect(struct tcpm_port *port)
  {
  	if (port->connected) {
  		typec_unregister_partner(port->partner);
  		port->partner = NULL;
  		port->connected = false;
  	}
  }
  
  static void tcpm_unregister_altmodes(struct tcpm_port *port)
  {
  	struct pd_mode_data *modep = &port->mode_data;
  	int i;
  
  	for (i = 0; i < modep->altmodes; i++) {
  		typec_unregister_altmode(port->partner_altmode[i]);
  		port->partner_altmode[i] = NULL;
  	}
  
  	memset(modep, 0, sizeof(*modep));
  }
  
  static void tcpm_reset_port(struct tcpm_port *port)
  {
  	tcpm_unregister_altmodes(port);
  	tcpm_typec_disconnect(port);
  	port->attached = false;
  	port->pd_capable = false;
  	port->pps_data.supported = false;
  
  	/*
  	 * First Rx ID should be 0; set this to a sentinel of -1 so that
  	 * we can check tcpm_pd_rx_handler() if we had seen it before.
  	 */
  	port->rx_msgid = -1;
  
  	port->tcpc->set_pd_rx(port->tcpc, false);
  	tcpm_init_vbus(port);	/* also disables charging */
  	tcpm_init_vconn(port);
  	tcpm_set_current_limit(port, 0, 0);
  	tcpm_set_polarity(port, TYPEC_POLARITY_CC1);
  	tcpm_mux_set(port, TYPEC_STATE_SAFE, USB_ROLE_NONE,
  		     TYPEC_ORIENTATION_NONE);
  	tcpm_set_attached_state(port, false);
  	port->try_src_count = 0;
  	port->try_snk_count = 0;
  	port->usb_type = POWER_SUPPLY_USB_TYPE_C;
  
  	power_supply_changed(port->psy);
  }
  
  static void tcpm_detach(struct tcpm_port *port)
  {
  	if (!port->attached)
  		return;
  
  	if (tcpm_port_is_disconnected(port))
  		port->hard_reset_count = 0;
  
  	tcpm_reset_port(port);
  }
  
  static void tcpm_src_detach(struct tcpm_port *port)
  {
  	tcpm_detach(port);
  }
  
  static int tcpm_snk_attach(struct tcpm_port *port)
  {
  	int ret;
  
  	if (port->attached)
  		return 0;
  
  	ret = tcpm_set_polarity(port, port->cc2 != TYPEC_CC_OPEN ?
  				TYPEC_POLARITY_CC2 : TYPEC_POLARITY_CC1);
  	if (ret < 0)
  		return ret;
  
  	ret = tcpm_set_roles(port, true, TYPEC_SINK, TYPEC_DEVICE);
  	if (ret < 0)
  		return ret;
  
  	port->pd_capable = false;
  
  	port->partner = NULL;
  
  	port->attached = true;
  	port->send_discover = true;
  
  	return 0;
  }
  
  static void tcpm_snk_detach(struct tcpm_port *port)
  {
  	tcpm_detach(port);
  }
  
  static int tcpm_acc_attach(struct tcpm_port *port)
  {
  	int ret;
  
  	if (port->attached)
  		return 0;
  
  	ret = tcpm_set_roles(port, true, TYPEC_SOURCE, TYPEC_HOST);
  	if (ret < 0)
  		return ret;
  
  	port->partner = NULL;
  
  	tcpm_typec_connect(port);
  
  	port->attached = true;
  
  	return 0;
  }
  
  static void tcpm_acc_detach(struct tcpm_port *port)
  {
  	tcpm_detach(port);
  }
  
  static inline enum tcpm_state hard_reset_state(struct tcpm_port *port)
  {
  	if (port->hard_reset_count < PD_N_HARD_RESET_COUNT)
  		return HARD_RESET_SEND;
  	if (port->pd_capable)
  		return ERROR_RECOVERY;
  	if (port->pwr_role == TYPEC_SOURCE)
  		return SRC_UNATTACHED;
  	if (port->state == SNK_WAIT_CAPABILITIES)
  		return SNK_READY;
  	return SNK_UNATTACHED;
  }
  
  static inline enum tcpm_state unattached_state(struct tcpm_port *port)
  {
  	if (port->port_type == TYPEC_PORT_DRP) {
  		if (port->pwr_role == TYPEC_SOURCE)
  			return SRC_UNATTACHED;
  		else
  			return SNK_UNATTACHED;
  	} else if (port->port_type == TYPEC_PORT_SRC) {
  		return SRC_UNATTACHED;
  	}
  
  	return SNK_UNATTACHED;
  }
  
  static void tcpm_check_send_discover(struct tcpm_port *port)
  {
  	if (port->data_role == TYPEC_HOST && port->send_discover &&
  	    port->pd_capable) {
  		tcpm_send_vdm(port, USB_SID_PD, CMD_DISCOVER_IDENT, NULL, 0);
  		port->send_discover = false;
  	}
  }
  
  static void tcpm_swap_complete(struct tcpm_port *port, int result)
  {
  	if (port->swap_pending) {
  		port->swap_status = result;
  		port->swap_pending = false;
  		port->non_pd_role_swap = false;
  		complete(&port->swap_complete);
  	}
  }
  
  static enum typec_pwr_opmode tcpm_get_pwr_opmode(enum typec_cc_status cc)
  {
  	switch (cc) {
  	case TYPEC_CC_RP_1_5:
  		return TYPEC_PWR_MODE_1_5A;
  	case TYPEC_CC_RP_3_0:
  		return TYPEC_PWR_MODE_3_0A;
  	case TYPEC_CC_RP_DEF:
  	default:
  		return TYPEC_PWR_MODE_USB;
  	}
  }
  
  static void run_state_machine(struct tcpm_port *port)
  {
  	int ret;
  	enum typec_pwr_opmode opmode;
  	unsigned int msecs;
  
  	port->enter_state = port->state;
  	switch (port->state) {
  	case TOGGLING:
  		break;
  	/* SRC states */
  	case SRC_UNATTACHED:
  		if (!port->non_pd_role_swap)
  			tcpm_swap_complete(port, -ENOTCONN);
  		tcpm_src_detach(port);
  		if (tcpm_start_toggling(port, tcpm_rp_cc(port))) {
  			tcpm_set_state(port, TOGGLING, 0);
  			break;
  		}
  		tcpm_set_cc(port, tcpm_rp_cc(port));
  		if (port->port_type == TYPEC_PORT_DRP)
  			tcpm_set_state(port, SNK_UNATTACHED, PD_T_DRP_SNK);
  		break;
  	case SRC_ATTACH_WAIT:
  		if (tcpm_port_is_debug(port))
  			tcpm_set_state(port, DEBUG_ACC_ATTACHED,
  				       PD_T_CC_DEBOUNCE);
  		else if (tcpm_port_is_audio(port))
  			tcpm_set_state(port, AUDIO_ACC_ATTACHED,
  				       PD_T_CC_DEBOUNCE);
  		else if (tcpm_port_is_source(port))
  			tcpm_set_state(port,
  				       tcpm_try_snk(port) ? SNK_TRY
  							  : SRC_ATTACHED,
  				       PD_T_CC_DEBOUNCE);
  		break;
  
  	case SNK_TRY:
  		port->try_snk_count++;
  		/*
  		 * Requirements:
  		 * - Do not drive vconn or vbus
  		 * - Terminate CC pins (both) to Rd
  		 * Action:
  		 * - Wait for tDRPTry (PD_T_DRP_TRY).
  		 *   Until then, ignore any state changes.
  		 */
  		tcpm_set_cc(port, TYPEC_CC_RD);
  		tcpm_set_state(port, SNK_TRY_WAIT, PD_T_DRP_TRY);
  		break;
  	case SNK_TRY_WAIT:
  		if (tcpm_port_is_sink(port)) {
  			tcpm_set_state(port, SNK_TRY_WAIT_DEBOUNCE, 0);
  		} else {
  			tcpm_set_state(port, SRC_TRYWAIT, 0);
  			port->max_wait = 0;
  		}
  		break;
  	case SNK_TRY_WAIT_DEBOUNCE:
  		tcpm_set_state(port, SNK_TRY_WAIT_DEBOUNCE_CHECK_VBUS,
  			       PD_T_PD_DEBOUNCE);
  		break;
  	case SNK_TRY_WAIT_DEBOUNCE_CHECK_VBUS:
  		if (port->vbus_present && tcpm_port_is_sink(port)) {
  			tcpm_set_state(port, SNK_ATTACHED, 0);
  		} else {
  			tcpm_set_state(port, SRC_TRYWAIT, 0);
  			port->max_wait = 0;
  		}
  		break;
  	case SRC_TRYWAIT:
  		tcpm_set_cc(port, tcpm_rp_cc(port));
  		if (port->max_wait == 0) {
  			port->max_wait = jiffies +
  					 msecs_to_jiffies(PD_T_DRP_TRY);
  			tcpm_set_state(port, SRC_TRYWAIT_UNATTACHED,
  				       PD_T_DRP_TRY);
  		} else {
  			if (time_is_after_jiffies(port->max_wait))
  				tcpm_set_state(port, SRC_TRYWAIT_UNATTACHED,
  					       jiffies_to_msecs(port->max_wait -
  								jiffies));
  			else
  				tcpm_set_state(port, SNK_UNATTACHED, 0);
  		}
  		break;
  	case SRC_TRYWAIT_DEBOUNCE:
  		tcpm_set_state(port, SRC_ATTACHED, PD_T_CC_DEBOUNCE);
  		break;
  	case SRC_TRYWAIT_UNATTACHED:
  		tcpm_set_state(port, SNK_UNATTACHED, 0);
  		break;
  
  	case SRC_ATTACHED:
  		ret = tcpm_src_attach(port);
  		tcpm_set_state(port, SRC_UNATTACHED,
  			       ret < 0 ? 0 : PD_T_PS_SOURCE_ON);
  		break;
  	case SRC_STARTUP:
  		opmode =  tcpm_get_pwr_opmode(tcpm_rp_cc(port));
  		typec_set_pwr_opmode(port->typec_port, opmode);
  		port->pwr_opmode = TYPEC_PWR_MODE_USB;
  		port->caps_count = 0;
  		port->negotiated_rev = PD_MAX_REV;
  		port->message_id = 0;
  		port->rx_msgid = -1;
  		port->explicit_contract = false;
  		tcpm_set_state(port, SRC_SEND_CAPABILITIES, 0);
  		break;
  	case SRC_SEND_CAPABILITIES:
  		port->caps_count++;
  		if (port->caps_count > PD_N_CAPS_COUNT) {
  			tcpm_set_state(port, SRC_READY, 0);
  			break;
  		}
  		ret = tcpm_pd_send_source_caps(port);
  		if (ret < 0) {
  			tcpm_set_state(port, SRC_SEND_CAPABILITIES,
  				       PD_T_SEND_SOURCE_CAP);
  		} else {
  			/*
  			 * Per standard, we should clear the reset counter here.
  			 * However, that can result in state machine hang-ups.
  			 * Reset it only in READY state to improve stability.
  			 */
  			/* port->hard_reset_count = 0; */
  			port->caps_count = 0;
  			port->pd_capable = true;
  			tcpm_set_state_cond(port, SRC_SEND_CAPABILITIES_TIMEOUT,
  					    PD_T_SEND_SOURCE_CAP);
  		}
  		break;
  	case SRC_SEND_CAPABILITIES_TIMEOUT:
  		/*
  		 * Error recovery for a PD_DATA_SOURCE_CAP reply timeout.
  		 *
  		 * PD 2.0 sinks are supposed to accept src-capabilities with a
  		 * 3.0 header and simply ignore any src PDOs which the sink does
  		 * not understand such as PPS but some 2.0 sinks instead ignore
  		 * the entire PD_DATA_SOURCE_CAP message, causing contract
  		 * negotiation to fail.
  		 *
  		 * After PD_N_HARD_RESET_COUNT hard-reset attempts, we try
  		 * sending src-capabilities with a lower PD revision to
  		 * make these broken sinks work.
  		 */
  		if (port->hard_reset_count < PD_N_HARD_RESET_COUNT) {
  			tcpm_set_state(port, HARD_RESET_SEND, 0);
  		} else if (port->negotiated_rev > PD_REV20) {
  			port->negotiated_rev--;
  			port->hard_reset_count = 0;
  			tcpm_set_state(port, SRC_SEND_CAPABILITIES, 0);
  		} else {
  			tcpm_set_state(port, hard_reset_state(port), 0);
  		}
  		break;
  	case SRC_NEGOTIATE_CAPABILITIES:
  		ret = tcpm_pd_check_request(port);
  		if (ret < 0) {
  			tcpm_pd_send_control(port, PD_CTRL_REJECT);
  			if (!port->explicit_contract) {
  				tcpm_set_state(port,
  					       SRC_WAIT_NEW_CAPABILITIES, 0);
  			} else {
  				tcpm_set_state(port, SRC_READY, 0);
  			}
  		} else {
  			tcpm_pd_send_control(port, PD_CTRL_ACCEPT);
  			tcpm_set_state(port, SRC_TRANSITION_SUPPLY,
  				       PD_T_SRC_TRANSITION);
  		}
  		break;
  	case SRC_TRANSITION_SUPPLY:
  		/* XXX: regulator_set_voltage(vbus, ...) */
  		tcpm_pd_send_control(port, PD_CTRL_PS_RDY);
  		port->explicit_contract = true;
  		typec_set_pwr_opmode(port->typec_port, TYPEC_PWR_MODE_PD);
  		port->pwr_opmode = TYPEC_PWR_MODE_PD;
  		tcpm_set_state_cond(port, SRC_READY, 0);
  		break;
  	case SRC_READY:
  #if 1
  		port->hard_reset_count = 0;
  #endif
  		port->try_src_count = 0;
  
  		tcpm_swap_complete(port, 0);
  		tcpm_typec_connect(port);
  
  		tcpm_check_send_discover(port);
  		/*
  		 * 6.3.5
  		 * Sending ping messages is not necessary if
  		 * - the source operates at vSafe5V
  		 * or
  		 * - The system is not operating in PD mode
  		 * or
  		 * - Both partners are connected using a Type-C connector
  		 *
  		 * There is no actual need to send PD messages since the local
  		 * port type-c and the spec does not clearly say whether PD is
  		 * possible when type-c is connected to Type-A/B
  		 */
  		break;
  	case SRC_WAIT_NEW_CAPABILITIES:
  		/* Nothing to do... */
  		break;
  
  	/* SNK states */
  	case SNK_UNATTACHED:
  		if (!port->non_pd_role_swap)
  			tcpm_swap_complete(port, -ENOTCONN);
  		tcpm_pps_complete(port, -ENOTCONN);
  		tcpm_snk_detach(port);
  		if (tcpm_start_toggling(port, TYPEC_CC_RD)) {
  			tcpm_set_state(port, TOGGLING, 0);
  			break;
  		}
  		tcpm_set_cc(port, TYPEC_CC_RD);
  		if (port->port_type == TYPEC_PORT_DRP)
  			tcpm_set_state(port, SRC_UNATTACHED, PD_T_DRP_SRC);
  		break;
  	case SNK_ATTACH_WAIT:
  		if ((port->cc1 == TYPEC_CC_OPEN &&
  		     port->cc2 != TYPEC_CC_OPEN) ||
  		    (port->cc1 != TYPEC_CC_OPEN &&
  		     port->cc2 == TYPEC_CC_OPEN))
  			tcpm_set_state(port, SNK_DEBOUNCED,
  				       PD_T_CC_DEBOUNCE);
  		else if (tcpm_port_is_disconnected(port))
  			tcpm_set_state(port, SNK_UNATTACHED,
  				       PD_T_PD_DEBOUNCE);
  		break;
  	case SNK_DEBOUNCED:
  		if (tcpm_port_is_disconnected(port))
  			tcpm_set_state(port, SNK_UNATTACHED,
  				       PD_T_PD_DEBOUNCE);
  		else if (port->vbus_present)
  			tcpm_set_state(port,
  				       tcpm_try_src(port) ? SRC_TRY
  							  : SNK_ATTACHED,
  				       0);
  		else
  			/* Wait for VBUS, but not forever */
  			tcpm_set_state(port, PORT_RESET, PD_T_PS_SOURCE_ON);
  		break;
  
  	case SRC_TRY:
  		port->try_src_count++;
  		tcpm_set_cc(port, tcpm_rp_cc(port));
  		port->max_wait = 0;
  		tcpm_set_state(port, SRC_TRY_WAIT, 0);
  		break;
  	case SRC_TRY_WAIT:
  		if (port->max_wait == 0) {
  			port->max_wait = jiffies +
  					 msecs_to_jiffies(PD_T_DRP_TRY);
  			msecs = PD_T_DRP_TRY;
  		} else {
  			if (time_is_after_jiffies(port->max_wait))
  				msecs = jiffies_to_msecs(port->max_wait -
  							 jiffies);
  			else
  				msecs = 0;
  		}
  		tcpm_set_state(port, SNK_TRYWAIT, msecs);
  		break;
  	case SRC_TRY_DEBOUNCE:
  		tcpm_set_state(port, SRC_ATTACHED, PD_T_PD_DEBOUNCE);
  		break;
  	case SNK_TRYWAIT:
  		tcpm_set_cc(port, TYPEC_CC_RD);
  		tcpm_set_state(port, SNK_TRYWAIT_VBUS, PD_T_CC_DEBOUNCE);
  		break;
  	case SNK_TRYWAIT_VBUS:
  		/*
  		 * TCPM stays in this state indefinitely until VBUS
  		 * is detected as long as Rp is not detected for
  		 * more than a time period of tPDDebounce.
  		 */
  		if (port->vbus_present && tcpm_port_is_sink(port)) {
  			tcpm_set_state(port, SNK_ATTACHED, 0);
  			break;
  		}
  		if (!tcpm_port_is_sink(port))
  			tcpm_set_state(port, SNK_TRYWAIT_DEBOUNCE, 0);
  		break;
  	case SNK_TRYWAIT_DEBOUNCE:
  		tcpm_set_state(port, SNK_UNATTACHED, PD_T_PD_DEBOUNCE);
  		break;
  	case SNK_ATTACHED:
  		ret = tcpm_snk_attach(port);
  		if (ret < 0)
  			tcpm_set_state(port, SNK_UNATTACHED, 0);
  		else
  			tcpm_set_state(port, SNK_STARTUP, 0);
  		break;
  	case SNK_STARTUP:
  		opmode =  tcpm_get_pwr_opmode(port->polarity ?
  					      port->cc2 : port->cc1);
  		typec_set_pwr_opmode(port->typec_port, opmode);
  		port->pwr_opmode = TYPEC_PWR_MODE_USB;
  		port->negotiated_rev = PD_MAX_REV;
  		port->message_id = 0;
  		port->rx_msgid = -1;
  		port->explicit_contract = false;
  		tcpm_set_state(port, SNK_DISCOVERY, 0);
  		break;
  	case SNK_DISCOVERY:
  		if (port->vbus_present) {
  			tcpm_set_current_limit(port,
  					       tcpm_get_current_limit(port),
  					       5000);
  			tcpm_set_charge(port, true);
  			tcpm_set_state(port, SNK_WAIT_CAPABILITIES, 0);
  			break;
  		}
  		/*
  		 * For DRP, timeouts differ. Also, handling is supposed to be
  		 * different and much more complex (dead battery detection;
  		 * see USB power delivery specification, section 8.3.3.6.1.5.1).
  		 */
  		tcpm_set_state(port, hard_reset_state(port),
  			       port->port_type == TYPEC_PORT_DRP ?
  					PD_T_DB_DETECT : PD_T_NO_RESPONSE);
  		break;
  	case SNK_DISCOVERY_DEBOUNCE:
  		tcpm_set_state(port, SNK_DISCOVERY_DEBOUNCE_DONE,
  			       PD_T_CC_DEBOUNCE);
  		break;
  	case SNK_DISCOVERY_DEBOUNCE_DONE:
  		if (!tcpm_port_is_disconnected(port) &&
  		    tcpm_port_is_sink(port) &&
  		    time_is_after_jiffies(port->delayed_runtime)) {
  			tcpm_set_state(port, SNK_DISCOVERY,
  				       jiffies_to_msecs(port->delayed_runtime -
  							jiffies));
  			break;
  		}
  		tcpm_set_state(port, unattached_state(port), 0);
  		break;
  	case SNK_WAIT_CAPABILITIES:
  		ret = port->tcpc->set_pd_rx(port->tcpc, true);
  		if (ret < 0) {
  			tcpm_set_state(port, SNK_READY, 0);
  			break;
  		}
  		/*
  		 * If VBUS has never been low, and we time out waiting
  		 * for source cap, try a soft reset first, in case we
  		 * were already in a stable contract before this boot.
  		 * Do this only once.
  		 */
  		if (port->vbus_never_low) {
  			port->vbus_never_low = false;
  			tcpm_set_state(port, SOFT_RESET_SEND,
  				       PD_T_SINK_WAIT_CAP);
  		} else {
  			tcpm_set_state(port, hard_reset_state(port),
  				       PD_T_SINK_WAIT_CAP);
  		}
  		break;
  	case SNK_NEGOTIATE_CAPABILITIES:
  		port->pd_capable = true;
  		port->hard_reset_count = 0;
  		ret = tcpm_pd_send_request(port);
  		if (ret < 0) {
  			/* Let the Source send capabilities again. */
  			tcpm_set_state(port, SNK_WAIT_CAPABILITIES, 0);
  		} else {
  			tcpm_set_state_cond(port, hard_reset_state(port),
  					    PD_T_SENDER_RESPONSE);
  		}
  		break;
  	case SNK_NEGOTIATE_PPS_CAPABILITIES:
  		ret = tcpm_pd_send_pps_request(port);
  		if (ret < 0) {
  			port->pps_status = ret;
  			/*
  			 * If this was called due to updates to sink
  			 * capabilities, and pps is no longer valid, we should
  			 * safely fall back to a standard PDO.
  			 */
  			if (port->update_sink_caps)
  				tcpm_set_state(port, SNK_NEGOTIATE_CAPABILITIES, 0);
  			else
  				tcpm_set_state(port, SNK_READY, 0);
  		} else {
  			tcpm_set_state_cond(port, hard_reset_state(port),
  					    PD_T_SENDER_RESPONSE);
  		}
  		break;
  	case SNK_TRANSITION_SINK:
  	case SNK_TRANSITION_SINK_VBUS:
  		tcpm_set_state(port, hard_reset_state(port),
  			       PD_T_PS_TRANSITION);
  		break;
  	case SNK_READY:
  		port->try_snk_count = 0;
  		port->update_sink_caps = false;
  		if (port->explicit_contract) {
  			typec_set_pwr_opmode(port->typec_port,
  					     TYPEC_PWR_MODE_PD);
  			port->pwr_opmode = TYPEC_PWR_MODE_PD;
  		}
  
  		tcpm_swap_complete(port, 0);
  		tcpm_typec_connect(port);
  		tcpm_check_send_discover(port);
  		tcpm_pps_complete(port, port->pps_status);
  
  		power_supply_changed(port->psy);
  
  		break;
  
  	/* Accessory states */
  	case ACC_UNATTACHED:
  		tcpm_acc_detach(port);
  		tcpm_set_state(port, SRC_UNATTACHED, 0);
  		break;
  	case DEBUG_ACC_ATTACHED:
  	case AUDIO_ACC_ATTACHED:
  		ret = tcpm_acc_attach(port);
  		if (ret < 0)
  			tcpm_set_state(port, ACC_UNATTACHED, 0);
  		break;
  	case AUDIO_ACC_DEBOUNCE:
  		tcpm_set_state(port, ACC_UNATTACHED, PD_T_CC_DEBOUNCE);
  		break;
  
  	/* Hard_Reset states */
  	case HARD_RESET_SEND:
  		tcpm_pd_transmit(port, TCPC_TX_HARD_RESET, NULL);
  		tcpm_set_state(port, HARD_RESET_START, 0);
  		break;
  	case HARD_RESET_START:
  		port->hard_reset_count++;
  		port->tcpc->set_pd_rx(port->tcpc, false);
  		tcpm_unregister_altmodes(port);
  		port->send_discover = true;
  		if (port->pwr_role == TYPEC_SOURCE)
  			tcpm_set_state(port, SRC_HARD_RESET_VBUS_OFF,
  				       PD_T_PS_HARD_RESET);
  		else
  			tcpm_set_state(port, SNK_HARD_RESET_SINK_OFF, 0);
  		break;
  	case SRC_HARD_RESET_VBUS_OFF:
  		tcpm_set_vconn(port, true);
  		tcpm_set_vbus(port, false);
  		tcpm_set_roles(port, port->self_powered, TYPEC_SOURCE,
  			       TYPEC_HOST);
  		tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, PD_T_SRC_RECOVER);
  		break;
  	case SRC_HARD_RESET_VBUS_ON:
  		tcpm_set_vbus(port, true);
  		port->tcpc->set_pd_rx(port->tcpc, true);
  		tcpm_set_attached_state(port, true);
  		tcpm_set_state(port, SRC_UNATTACHED, PD_T_PS_SOURCE_ON);
  		break;
  	case SNK_HARD_RESET_SINK_OFF:
  		memset(&port->pps_data, 0, sizeof(port->pps_data));
  		tcpm_set_vconn(port, false);
  		if (port->pd_capable)
  			tcpm_set_charge(port, false);
  		tcpm_set_roles(port, port->self_powered, TYPEC_SINK,
  			       TYPEC_DEVICE);
  		/*
  		 * VBUS may or may not toggle, depending on the adapter.
  		 * If it doesn't toggle, transition to SNK_HARD_RESET_SINK_ON
  		 * directly after timeout.
  		 */
  		tcpm_set_state(port, SNK_HARD_RESET_SINK_ON, PD_T_SAFE_0V);
  		break;
  	case SNK_HARD_RESET_WAIT_VBUS:
  		/* Assume we're disconnected if VBUS doesn't come back. */
  		tcpm_set_state(port, SNK_UNATTACHED,
  			       PD_T_SRC_RECOVER_MAX + PD_T_SRC_TURN_ON);
  		break;
  	case SNK_HARD_RESET_SINK_ON:
  		/* Note: There is no guarantee that VBUS is on in this state */
  		/*
  		 * XXX:
  		 * The specification suggests that dual mode ports in sink
  		 * mode should transition to state PE_SRC_Transition_to_default.
  		 * See USB power delivery specification chapter 8.3.3.6.1.3.
  		 * This would mean to to
  		 * - turn off VCONN, reset power supply
  		 * - request hardware reset
  		 * - turn on VCONN
  		 * - Transition to state PE_Src_Startup
  		 * SNK only ports shall transition to state Snk_Startup
  		 * (see chapter 8.3.3.3.8).
  		 * Similar, dual-mode ports in source mode should transition
  		 * to PE_SNK_Transition_to_default.
  		 */
  		if (port->pd_capable) {
  			tcpm_set_current_limit(port,
  					       tcpm_get_current_limit(port),
  					       5000);
  			tcpm_set_charge(port, true);
  		}
  		tcpm_set_attached_state(port, true);
  		tcpm_set_state(port, SNK_STARTUP, 0);
  		break;
  
  	/* Soft_Reset states */
  	case SOFT_RESET:
  		port->message_id = 0;
  		port->rx_msgid = -1;
  		tcpm_pd_send_control(port, PD_CTRL_ACCEPT);
  		if (port->pwr_role == TYPEC_SOURCE)
  			tcpm_set_state(port, SRC_SEND_CAPABILITIES, 0);
  		else
  			tcpm_set_state(port, SNK_WAIT_CAPABILITIES, 0);
  		break;
  	case SOFT_RESET_SEND:
  		port->message_id = 0;
  		port->rx_msgid = -1;
  		if (tcpm_pd_send_control(port, PD_CTRL_SOFT_RESET))
  			tcpm_set_state_cond(port, hard_reset_state(port), 0);
  		else
  			tcpm_set_state_cond(port, hard_reset_state(port),
  					    PD_T_SENDER_RESPONSE);
  		break;
  
  	/* DR_Swap states */
  	case DR_SWAP_SEND:
  		tcpm_pd_send_control(port, PD_CTRL_DR_SWAP);
  		tcpm_set_state_cond(port, DR_SWAP_SEND_TIMEOUT,
  				    PD_T_SENDER_RESPONSE);
  		break;
  	case DR_SWAP_ACCEPT:
  		tcpm_pd_send_control(port, PD_CTRL_ACCEPT);
  		tcpm_set_state_cond(port, DR_SWAP_CHANGE_DR, 0);
  		break;
  	case DR_SWAP_SEND_TIMEOUT:
  		tcpm_swap_complete(port, -ETIMEDOUT);
  		tcpm_set_state(port, ready_state(port), 0);
  		break;
  	case DR_SWAP_CHANGE_DR:
  		if (port->data_role == TYPEC_HOST) {
  			tcpm_unregister_altmodes(port);
  			tcpm_set_roles(port, true, port->pwr_role,
  				       TYPEC_DEVICE);
  		} else {
  			tcpm_set_roles(port, true, port->pwr_role,
  				       TYPEC_HOST);
  			port->send_discover = true;
  		}
  		tcpm_set_state(port, ready_state(port), 0);
  		break;
  
  	/* PR_Swap states */
  	case PR_SWAP_ACCEPT:
  		tcpm_pd_send_control(port, PD_CTRL_ACCEPT);
  		tcpm_set_state(port, PR_SWAP_START, 0);
  		break;
  	case PR_SWAP_SEND:
  		tcpm_pd_send_control(port, PD_CTRL_PR_SWAP);
  		tcpm_set_state_cond(port, PR_SWAP_SEND_TIMEOUT,
  				    PD_T_SENDER_RESPONSE);
  		break;
  	case PR_SWAP_SEND_TIMEOUT:
  		tcpm_swap_complete(port, -ETIMEDOUT);
  		tcpm_set_state(port, ready_state(port), 0);
  		break;
  	case PR_SWAP_START:
  		if (port->pwr_role == TYPEC_SOURCE)
  			tcpm_set_state(port, PR_SWAP_SRC_SNK_TRANSITION_OFF,
  				       PD_T_SRC_TRANSITION);
  		else
  			tcpm_set_state(port, PR_SWAP_SNK_SRC_SINK_OFF, 0);
  		break;
  	case PR_SWAP_SRC_SNK_TRANSITION_OFF:
  		tcpm_set_vbus(port, false);
  		port->explicit_contract = false;
  		/* allow time for Vbus discharge, must be < tSrcSwapStdby */
  		tcpm_set_state(port, PR_SWAP_SRC_SNK_SOURCE_OFF,
  			       PD_T_SRCSWAPSTDBY);
  		break;
  	case PR_SWAP_SRC_SNK_SOURCE_OFF:
  		tcpm_set_cc(port, TYPEC_CC_RD);
  		/* allow CC debounce */
  		tcpm_set_state(port, PR_SWAP_SRC_SNK_SOURCE_OFF_CC_DEBOUNCED,
  			       PD_T_CC_DEBOUNCE);
  		break;
  	case PR_SWAP_SRC_SNK_SOURCE_OFF_CC_DEBOUNCED:
  		/*
  		 * USB-PD standard, 6.2.1.4, Port Power Role:
  		 * "During the Power Role Swap Sequence, for the initial Source
  		 * Port, the Port Power Role field shall be set to Sink in the
  		 * PS_RDY Message indicating that the initial Source’s power
  		 * supply is turned off"
  		 */
  		tcpm_set_pwr_role(port, TYPEC_SINK);
  		if (tcpm_pd_send_control(port, PD_CTRL_PS_RDY)) {
  			tcpm_set_state(port, ERROR_RECOVERY, 0);
  			break;
  		}
  		tcpm_set_state_cond(port, SNK_UNATTACHED, PD_T_PS_SOURCE_ON);
  		break;
  	case PR_SWAP_SRC_SNK_SINK_ON:
  		tcpm_set_state(port, SNK_STARTUP, 0);
  		break;
  	case PR_SWAP_SNK_SRC_SINK_OFF:
  		tcpm_set_charge(port, false);
  		tcpm_set_state(port, hard_reset_state(port),
  			       PD_T_PS_SOURCE_OFF);
  		break;
  	case PR_SWAP_SNK_SRC_SOURCE_ON:
  		tcpm_set_cc(port, tcpm_rp_cc(port));
  		tcpm_set_vbus(port, true);
  		/*
  		 * allow time VBUS ramp-up, must be < tNewSrc
  		 * Also, this window overlaps with CC debounce as well.
  		 * So, Wait for the max of two which is PD_T_NEWSRC
  		 */
  		tcpm_set_state(port, PR_SWAP_SNK_SRC_SOURCE_ON_VBUS_RAMPED_UP,
  			       PD_T_NEWSRC);
  		break;
  	case PR_SWAP_SNK_SRC_SOURCE_ON_VBUS_RAMPED_UP:
  		/*
  		 * USB PD standard, 6.2.1.4:
  		 * "Subsequent Messages initiated by the Policy Engine,
  		 * such as the PS_RDY Message sent to indicate that Vbus
  		 * is ready, will have the Port Power Role field set to
  		 * Source."
  		 */
  		tcpm_set_pwr_role(port, TYPEC_SOURCE);
  		tcpm_pd_send_control(port, PD_CTRL_PS_RDY);
  		tcpm_set_state(port, SRC_STARTUP, 0);
  		break;
  
  	case VCONN_SWAP_ACCEPT:
  		tcpm_pd_send_control(port, PD_CTRL_ACCEPT);
  		tcpm_set_state(port, VCONN_SWAP_START, 0);
  		break;
  	case VCONN_SWAP_SEND:
  		tcpm_pd_send_control(port, PD_CTRL_VCONN_SWAP);
  		tcpm_set_state(port, VCONN_SWAP_SEND_TIMEOUT,
  			       PD_T_SENDER_RESPONSE);
  		break;
  	case VCONN_SWAP_SEND_TIMEOUT:
  		tcpm_swap_complete(port, -ETIMEDOUT);
  		tcpm_set_state(port, ready_state(port), 0);
  		break;
  	case VCONN_SWAP_START:
  		if (port->vconn_role == TYPEC_SOURCE)
  			tcpm_set_state(port, VCONN_SWAP_WAIT_FOR_VCONN, 0);
  		else
  			tcpm_set_state(port, VCONN_SWAP_TURN_ON_VCONN, 0);
  		break;
  	case VCONN_SWAP_WAIT_FOR_VCONN:
  		tcpm_set_state(port, hard_reset_state(port),
  			       PD_T_VCONN_SOURCE_ON);
  		break;
  	case VCONN_SWAP_TURN_ON_VCONN:
  		tcpm_set_vconn(port, true);
  		tcpm_pd_send_control(port, PD_CTRL_PS_RDY);
  		tcpm_set_state(port, ready_state(port), 0);
  		break;
  	case VCONN_SWAP_TURN_OFF_VCONN:
  		tcpm_set_vconn(port, false);
  		tcpm_set_state(port, ready_state(port), 0);
  		break;
  
  	case DR_SWAP_CANCEL:
  	case PR_SWAP_CANCEL:
  	case VCONN_SWAP_CANCEL:
  		tcpm_swap_complete(port, port->swap_status);
  		if (port->pwr_role == TYPEC_SOURCE)
  			tcpm_set_state(port, SRC_READY, 0);
  		else
  			tcpm_set_state(port, SNK_READY, 0);
  		break;
  
  	case BIST_RX:
  		switch (BDO_MODE_MASK(port->bist_request)) {
  		case BDO_MODE_CARRIER2:
  			tcpm_pd_transmit(port, TCPC_TX_BIST_MODE_2, NULL);
  			break;
  		default:
  			break;
  		}
  		/* Always switch to unattached state */
  		tcpm_set_state(port, unattached_state(port), 0);
  		break;
  	case GET_STATUS_SEND:
  		tcpm_pd_send_control(port, PD_CTRL_GET_STATUS);
  		tcpm_set_state(port, GET_STATUS_SEND_TIMEOUT,
  			       PD_T_SENDER_RESPONSE);
  		break;
  	case GET_STATUS_SEND_TIMEOUT:
  		tcpm_set_state(port, ready_state(port), 0);
  		break;
  	case GET_PPS_STATUS_SEND:
  		tcpm_pd_send_control(port, PD_CTRL_GET_PPS_STATUS);
  		tcpm_set_state(port, GET_PPS_STATUS_SEND_TIMEOUT,
  			       PD_T_SENDER_RESPONSE);
  		break;
  	case GET_PPS_STATUS_SEND_TIMEOUT:
  		tcpm_set_state(port, ready_state(port), 0);
  		break;
  	case ERROR_RECOVERY:
  		tcpm_swap_complete(port, -EPROTO);
  		tcpm_pps_complete(port, -EPROTO);
  		tcpm_set_state(port, PORT_RESET, 0);
  		break;
  	case PORT_RESET:
  		tcpm_reset_port(port);
  		tcpm_set_cc(port, TYPEC_CC_OPEN);
  		tcpm_set_state(port, PORT_RESET_WAIT_OFF,
  			       PD_T_ERROR_RECOVERY);
  		break;
  	case PORT_RESET_WAIT_OFF:
  		tcpm_set_state(port,
  			       tcpm_default_state(port),
  			       port->vbus_present ? PD_T_PS_SOURCE_OFF : 0);
  		break;
  	default:
  		WARN(1, "Unexpected port state %d\n", port->state);
  		break;
  	}
  }
  
  static void tcpm_state_machine_work(struct work_struct *work)
  {
  	struct tcpm_port *port = container_of(work, struct tcpm_port,
  					      state_machine.work);
  	enum tcpm_state prev_state;
  
  	mutex_lock(&port->lock);
  	port->state_machine_running = true;
  
  	if (port->queued_message && tcpm_send_queued_message(port))
  		goto done;
  
  	/* If we were queued due to a delayed state change, update it now */
  	if (port->delayed_state) {
  		tcpm_log(port, "state change %s -> %s [delayed %ld ms]",
  			 tcpm_states[port->state],
  			 tcpm_states[port->delayed_state], port->delay_ms);
  		port->prev_state = port->state;
  		port->state = port->delayed_state;
  		port->delayed_state = INVALID_STATE;
  	}
  
  	/*
  	 * Continue running as long as we have (non-delayed) state changes
  	 * to make.
  	 */
  	do {
  		prev_state = port->state;
  		run_state_machine(port);
  		if (port->queued_message)
  			tcpm_send_queued_message(port);
  	} while (port->state != prev_state && !port->delayed_state);
  
  done:
  	port->state_machine_running = false;
  	mutex_unlock(&port->lock);
  }
  
  static void _tcpm_cc_change(struct tcpm_port *port, enum typec_cc_status cc1,
  			    enum typec_cc_status cc2)
  {
  	enum typec_cc_status old_cc1, old_cc2;
  	enum tcpm_state new_state;
  
  	old_cc1 = port->cc1;
  	old_cc2 = port->cc2;
  	port->cc1 = cc1;
  	port->cc2 = cc2;
  
  	tcpm_log_force(port,
  		       "CC1: %u -> %u, CC2: %u -> %u [state %s, polarity %d, %s]",
  		       old_cc1, cc1, old_cc2, cc2, tcpm_states[port->state],
  		       port->polarity,
  		       tcpm_port_is_disconnected(port) ? "disconnected"
  						       : "connected");
  
  	switch (port->state) {
  	case TOGGLING:
  		if (tcpm_port_is_debug(port) || tcpm_port_is_audio(port) ||
  		    tcpm_port_is_source(port))
  			tcpm_set_state(port, SRC_ATTACH_WAIT, 0);
  		else if (tcpm_port_is_sink(port))
  			tcpm_set_state(port, SNK_ATTACH_WAIT, 0);
  		break;
  	case SRC_UNATTACHED:
  	case ACC_UNATTACHED:
  		if (tcpm_port_is_debug(port) || tcpm_port_is_audio(port) ||
  		    tcpm_port_is_source(port))
  			tcpm_set_state(port, SRC_ATTACH_WAIT, 0);
  		break;
  	case SRC_ATTACH_WAIT:
  		if (tcpm_port_is_disconnected(port) ||
  		    tcpm_port_is_audio_detached(port))
  			tcpm_set_state(port, SRC_UNATTACHED, 0);
  		else if (cc1 != old_cc1 || cc2 != old_cc2)
  			tcpm_set_state(port, SRC_ATTACH_WAIT, 0);
  		break;
  	case SRC_ATTACHED:
  	case SRC_SEND_CAPABILITIES:
  	case SRC_READY:
  		if (tcpm_port_is_disconnected(port) ||
  		    !tcpm_port_is_source(port))
  			tcpm_set_state(port, SRC_UNATTACHED, 0);
  		break;
  	case SNK_UNATTACHED:
  		if (tcpm_port_is_sink(port))
  			tcpm_set_state(port, SNK_ATTACH_WAIT, 0);
  		break;
  	case SNK_ATTACH_WAIT:
  		if ((port->cc1 == TYPEC_CC_OPEN &&
  		     port->cc2 != TYPEC_CC_OPEN) ||
  		    (port->cc1 != TYPEC_CC_OPEN &&
  		     port->cc2 == TYPEC_CC_OPEN))
  			new_state = SNK_DEBOUNCED;
  		else if (tcpm_port_is_disconnected(port))
  			new_state = SNK_UNATTACHED;
  		else
  			break;
  		if (new_state != port->delayed_state)
  			tcpm_set_state(port, SNK_ATTACH_WAIT, 0);
  		break;
  	case SNK_DEBOUNCED:
  		if (tcpm_port_is_disconnected(port))
  			new_state = SNK_UNATTACHED;
  		else if (port->vbus_present)
  			new_state = tcpm_try_src(port) ? SRC_TRY : SNK_ATTACHED;
  		else
  			new_state = SNK_UNATTACHED;
  		if (new_state != port->delayed_state)
  			tcpm_set_state(port, SNK_DEBOUNCED, 0);
  		break;
  	case SNK_READY:
  		if (tcpm_port_is_disconnected(port))
  			tcpm_set_state(port, unattached_state(port), 0);
  		else if (!port->pd_capable &&
  			 (cc1 != old_cc1 || cc2 != old_cc2))
  			tcpm_set_current_limit(port,
  					       tcpm_get_current_limit(port),
  					       5000);
  		break;
  
  	case AUDIO_ACC_ATTACHED:
  		if (cc1 == TYPEC_CC_OPEN || cc2 == TYPEC_CC_OPEN)
  			tcpm_set_state(port, AUDIO_ACC_DEBOUNCE, 0);
  		break;
  	case AUDIO_ACC_DEBOUNCE:
  		if (tcpm_port_is_audio(port))
  			tcpm_set_state(port, AUDIO_ACC_ATTACHED, 0);
  		break;
  
  	case DEBUG_ACC_ATTACHED:
  		if (cc1 == TYPEC_CC_OPEN || cc2 == TYPEC_CC_OPEN)
  			tcpm_set_state(port, ACC_UNATTACHED, 0);
  		break;
  
  	case SNK_TRY:
  		/* Do nothing, waiting for timeout */
  		break;
  
  	case SNK_DISCOVERY:
  		/* CC line is unstable, wait for debounce */
  		if (tcpm_port_is_disconnected(port))
  			tcpm_set_state(port, SNK_DISCOVERY_DEBOUNCE, 0);
  		break;
  	case SNK_DISCOVERY_DEBOUNCE:
  		break;
  
  	case SRC_TRYWAIT:
  		/* Hand over to state machine if needed */
  		if (!port->vbus_present && tcpm_port_is_source(port))
  			tcpm_set_state(port, SRC_TRYWAIT_DEBOUNCE, 0);
  		break;
  	case SRC_TRYWAIT_DEBOUNCE:
  		if (port->vbus_present || !tcpm_port_is_source(port))
  			tcpm_set_state(port, SRC_TRYWAIT, 0);
  		break;
  	case SNK_TRY_WAIT_DEBOUNCE:
  		if (!tcpm_port_is_sink(port)) {
  			port->max_wait = 0;
  			tcpm_set_state(port, SRC_TRYWAIT, 0);
  		}
  		break;
  	case SRC_TRY_WAIT:
  		if (tcpm_port_is_source(port))
  			tcpm_set_state(port, SRC_TRY_DEBOUNCE, 0);
  		break;
  	case SRC_TRY_DEBOUNCE:
  		tcpm_set_state(port, SRC_TRY_WAIT, 0);
  		break;
  	case SNK_TRYWAIT_DEBOUNCE:
  		if (tcpm_port_is_sink(port))
  			tcpm_set_state(port, SNK_TRYWAIT_VBUS, 0);
  		break;
  	case SNK_TRYWAIT_VBUS:
  		if (!tcpm_port_is_sink(port))
  			tcpm_set_state(port, SNK_TRYWAIT_DEBOUNCE, 0);
  		break;
  	case SNK_TRYWAIT:
  		/* Do nothing, waiting for tCCDebounce */
  		break;
  	case PR_SWAP_SNK_SRC_SINK_OFF:
  	case PR_SWAP_SRC_SNK_TRANSITION_OFF:
  	case PR_SWAP_SRC_SNK_SOURCE_OFF:
  	case PR_SWAP_SRC_SNK_SOURCE_OFF_CC_DEBOUNCED:
  	case PR_SWAP_SNK_SRC_SOURCE_ON:
  		/*
  		 * CC state change is expected in PR_SWAP
  		 * Ignore it.
  		 */
  		break;
  
  	case PORT_RESET:
  	case PORT_RESET_WAIT_OFF:
  		/*
  		 * State set back to default mode once the timer completes.
  		 * Ignore CC changes here.
  		 */
  		break;
  
  	default:
  		if (tcpm_port_is_disconnected(port))
  			tcpm_set_state(port, unattached_state(port), 0);
  		break;
  	}
  }
  
  static void _tcpm_pd_vbus_on(struct tcpm_port *port)
  {
  	tcpm_log_force(port, "VBUS on");
  	port->vbus_present = true;
  	switch (port->state) {
  	case SNK_TRANSITION_SINK_VBUS:
  		port->explicit_contract = true;
  		tcpm_set_state(port, SNK_READY, 0);
  		break;
  	case SNK_DISCOVERY:
  		tcpm_set_state(port, SNK_DISCOVERY, 0);
  		break;
  
  	case SNK_DEBOUNCED:
  		tcpm_set_state(port, tcpm_try_src(port) ? SRC_TRY
  							: SNK_ATTACHED,
  				       0);
  		break;
  	case SNK_HARD_RESET_WAIT_VBUS:
  		tcpm_set_state(port, SNK_HARD_RESET_SINK_ON, 0);
  		break;
  	case SRC_ATTACHED:
  		tcpm_set_state(port, SRC_STARTUP, 0);
  		break;
  	case SRC_HARD_RESET_VBUS_ON:
  		tcpm_set_state(port, SRC_STARTUP, 0);
  		break;
  
  	case SNK_TRY:
  		/* Do nothing, waiting for timeout */
  		break;
  	case SRC_TRYWAIT:
  		/* Do nothing, Waiting for Rd to be detected */
  		break;
  	case SRC_TRYWAIT_DEBOUNCE:
  		tcpm_set_state(port, SRC_TRYWAIT, 0);
  		break;
  	case SNK_TRY_WAIT_DEBOUNCE:
  		/* Do nothing, waiting for PD_DEBOUNCE to do be done */
  		break;
  	case SNK_TRYWAIT:
  		/* Do nothing, waiting for tCCDebounce */
  		break;
  	case SNK_TRYWAIT_VBUS:
  		if (tcpm_port_is_sink(port))
  			tcpm_set_state(port, SNK_ATTACHED, 0);
  		break;
  	case SNK_TRYWAIT_DEBOUNCE:
  		/* Do nothing, waiting for Rp */
  		break;
  	case SRC_TRY_WAIT:
  	case SRC_TRY_DEBOUNCE:
  		/* Do nothing, waiting for sink detection */
  		break;
  
  	case PORT_RESET:
  	case PORT_RESET_WAIT_OFF:
  		/*
  		 * State set back to default mode once the timer completes.
  		 * Ignore vbus changes here.
  		 */
  		break;
  
  	default:
  		break;
  	}
  }
  
  static void _tcpm_pd_vbus_off(struct tcpm_port *port)
  {
  	tcpm_log_force(port, "VBUS off");
  	port->vbus_present = false;
  	port->vbus_never_low = false;
  	switch (port->state) {
  	case SNK_HARD_RESET_SINK_OFF:
  		tcpm_set_state(port, SNK_HARD_RESET_WAIT_VBUS, 0);
  		break;
  	case SRC_HARD_RESET_VBUS_OFF:
  		tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, 0);
  		break;
  	case HARD_RESET_SEND:
  		break;
  
  	case SNK_TRY:
  		/* Do nothing, waiting for timeout */
  		break;
  	case SRC_TRYWAIT:
  		/* Hand over to state machine if needed */
  		if (tcpm_port_is_source(port))
  			tcpm_set_state(port, SRC_TRYWAIT_DEBOUNCE, 0);
  		break;
  	case SNK_TRY_WAIT_DEBOUNCE:
  		/* Do nothing, waiting for PD_DEBOUNCE to do be done */
  		break;
  	case SNK_TRYWAIT:
  	case SNK_TRYWAIT_VBUS:
  	case SNK_TRYWAIT_DEBOUNCE:
  		break;
  	case SNK_ATTACH_WAIT:
  		tcpm_set_state(port, SNK_UNATTACHED, 0);
  		break;
  
  	case SNK_NEGOTIATE_CAPABILITIES:
  		break;
  
  	case PR_SWAP_SRC_SNK_TRANSITION_OFF:
  		tcpm_set_state(port, PR_SWAP_SRC_SNK_SOURCE_OFF, 0);
  		break;
  
  	case PR_SWAP_SNK_SRC_SINK_OFF:
  		/* Do nothing, expected */
  		break;
  
  	case PORT_RESET_WAIT_OFF:
  		tcpm_set_state(port, tcpm_default_state(port), 0);
  		break;
  
  	case SRC_TRY_WAIT:
  	case SRC_TRY_DEBOUNCE:
  		/* Do nothing, waiting for sink detection */
  		break;
  
  	case PORT_RESET:
  		/*
  		 * State set back to default mode once the timer completes.
  		 * Ignore vbus changes here.
  		 */
  		break;
  
  	default:
  		if (port->pwr_role == TYPEC_SINK &&
  		    port->attached)
  			tcpm_set_state(port, SNK_UNATTACHED, 0);
  		break;
  	}
  }
  
  static void _tcpm_pd_hard_reset(struct tcpm_port *port)
  {
  	tcpm_log_force(port, "Received hard reset");
  	/*
  	 * If we keep receiving hard reset requests, executing the hard reset
  	 * must have failed. Revert to error recovery if that happens.
  	 */
  	tcpm_set_state(port,
  		       port->hard_reset_count < PD_N_HARD_RESET_COUNT ?
  				HARD_RESET_START : ERROR_RECOVERY,
  		       0);
  }
  
  static void tcpm_pd_event_handler(struct work_struct *work)
  {
  	struct tcpm_port *port = container_of(work, struct tcpm_port,
  					      event_work);
  	u32 events;
  
  	mutex_lock(&port->lock);
  
  	spin_lock(&port->pd_event_lock);
  	while (port->pd_events) {
  		events = port->pd_events;
  		port->pd_events = 0;
  		spin_unlock(&port->pd_event_lock);
  		if (events & TCPM_RESET_EVENT)
  			_tcpm_pd_hard_reset(port);
  		if (events & TCPM_VBUS_EVENT) {
  			bool vbus;
  
  			vbus = port->tcpc->get_vbus(port->tcpc);
  			if (vbus)
  				_tcpm_pd_vbus_on(port);
  			else
  				_tcpm_pd_vbus_off(port);
  		}
  		if (events & TCPM_CC_EVENT) {
  			enum typec_cc_status cc1, cc2;
  
  			if (port->tcpc->get_cc(port->tcpc, &cc1, &cc2) == 0)
  				_tcpm_cc_change(port, cc1, cc2);
  		}
  		spin_lock(&port->pd_event_lock);
  	}
  	spin_unlock(&port->pd_event_lock);
  	mutex_unlock(&port->lock);
  }
  
  void tcpm_cc_change(struct tcpm_port *port)
  {
  	spin_lock(&port->pd_event_lock);
  	port->pd_events |= TCPM_CC_EVENT;
  	spin_unlock(&port->pd_event_lock);
  	queue_work(port->wq, &port->event_work);
  }
  EXPORT_SYMBOL_GPL(tcpm_cc_change);
  
  void tcpm_vbus_change(struct tcpm_port *port)
  {
  	spin_lock(&port->pd_event_lock);
  	port->pd_events |= TCPM_VBUS_EVENT;
  	spin_unlock(&port->pd_event_lock);
  	queue_work(port->wq, &port->event_work);
  }
  EXPORT_SYMBOL_GPL(tcpm_vbus_change);
  
  void tcpm_pd_hard_reset(struct tcpm_port *port)
  {
  	spin_lock(&port->pd_event_lock);
  	port->pd_events = TCPM_RESET_EVENT;
  	spin_unlock(&port->pd_event_lock);
  	queue_work(port->wq, &port->event_work);
  }
  EXPORT_SYMBOL_GPL(tcpm_pd_hard_reset);
  
  static int tcpm_dr_set(const struct typec_capability *cap,
  		       enum typec_data_role data)
  {
  	struct tcpm_port *port = typec_cap_to_tcpm(cap);
  	int ret;
  
  	mutex_lock(&port->swap_lock);
  	mutex_lock(&port->lock);
  
  	if (port->port_type != TYPEC_PORT_DRP) {
  		ret = -EINVAL;
  		goto port_unlock;
  	}
  	if (port->state != SRC_READY && port->state != SNK_READY) {
  		ret = -EAGAIN;
  		goto port_unlock;
  	}
  
  	if (port->data_role == data) {
  		ret = 0;
  		goto port_unlock;
  	}
  
  	/*
  	 * XXX
  	 * 6.3.9: If an alternate mode is active, a request to swap
  	 * alternate modes shall trigger a port reset.
  	 * Reject data role swap request in this case.
  	 */
  
  	if (!port->pd_capable) {
  		/*
  		 * If the partner is not PD capable, reset the port to
  		 * trigger a role change. This can only work if a preferred
  		 * role is configured, and if it matches the requested role.
  		 */
  		if (port->try_role == TYPEC_NO_PREFERRED_ROLE ||
  		    port->try_role == port->pwr_role) {
  			ret = -EINVAL;
  			goto port_unlock;
  		}
  		port->non_pd_role_swap = true;
  		tcpm_set_state(port, PORT_RESET, 0);
  	} else {
  		tcpm_set_state(port, DR_SWAP_SEND, 0);
  	}
  
  	port->swap_status = 0;
  	port->swap_pending = true;
  	reinit_completion(&port->swap_complete);
  	mutex_unlock(&port->lock);
  
  	if (!wait_for_completion_timeout(&port->swap_complete,
  				msecs_to_jiffies(PD_ROLE_SWAP_TIMEOUT)))
  		ret = -ETIMEDOUT;
  	else
  		ret = port->swap_status;
  
  	port->non_pd_role_swap = false;
  	goto swap_unlock;
  
  port_unlock:
  	mutex_unlock(&port->lock);
  swap_unlock:
  	mutex_unlock(&port->swap_lock);
  	return ret;
  }
  
  static int tcpm_pr_set(const struct typec_capability *cap,
  		       enum typec_role role)
  {
  	struct tcpm_port *port = typec_cap_to_tcpm(cap);
  	int ret;
  
  	mutex_lock(&port->swap_lock);
  	mutex_lock(&port->lock);
  
  	if (port->port_type != TYPEC_PORT_DRP) {
  		ret = -EINVAL;
  		goto port_unlock;
  	}
  	if (port->state != SRC_READY && port->state != SNK_READY) {
  		ret = -EAGAIN;
  		goto port_unlock;
  	}
  
  	if (role == port->pwr_role) {
  		ret = 0;
  		goto port_unlock;
  	}
  
  	port->swap_status = 0;
  	port->swap_pending = true;
  	reinit_completion(&port->swap_complete);
  	tcpm_set_state(port, PR_SWAP_SEND, 0);
  	mutex_unlock(&port->lock);
  
  	if (!wait_for_completion_timeout(&port->swap_complete,
  				msecs_to_jiffies(PD_ROLE_SWAP_TIMEOUT)))
  		ret = -ETIMEDOUT;
  	else
  		ret = port->swap_status;
  
  	goto swap_unlock;
  
  port_unlock:
  	mutex_unlock(&port->lock);
  swap_unlock:
  	mutex_unlock(&port->swap_lock);
  	return ret;
  }
  
  static int tcpm_vconn_set(const struct typec_capability *cap,
  			  enum typec_role role)
  {
  	struct tcpm_port *port = typec_cap_to_tcpm(cap);
  	int ret;
  
  	mutex_lock(&port->swap_lock);
  	mutex_lock(&port->lock);
  
  	if (port->state != SRC_READY && port->state != SNK_READY) {
  		ret = -EAGAIN;
  		goto port_unlock;
  	}
  
  	if (role == port->vconn_role) {
  		ret = 0;
  		goto port_unlock;
  	}
  
  	port->swap_status = 0;
  	port->swap_pending = true;
  	reinit_completion(&port->swap_complete);
  	tcpm_set_state(port, VCONN_SWAP_SEND, 0);
  	mutex_unlock(&port->lock);
  
  	if (!wait_for_completion_timeout(&port->swap_complete,
  				msecs_to_jiffies(PD_ROLE_SWAP_TIMEOUT)))
  		ret = -ETIMEDOUT;
  	else
  		ret = port->swap_status;
  
  	goto swap_unlock;
  
  port_unlock:
  	mutex_unlock(&port->lock);
  swap_unlock:
  	mutex_unlock(&port->swap_lock);
  	return ret;
  }
  
  static int tcpm_try_role(const struct typec_capability *cap, int role)
  {
  	struct tcpm_port *port = typec_cap_to_tcpm(cap);
  	struct tcpc_dev	*tcpc = port->tcpc;
  	int ret = 0;
  
  	mutex_lock(&port->lock);
  	if (tcpc->try_role)
  		ret = tcpc->try_role(tcpc, role);
  	if (!ret && (!tcpc->config || !tcpc->config->try_role_hw))
  		port->try_role = role;
  	port->try_src_count = 0;
  	port->try_snk_count = 0;
  	mutex_unlock(&port->lock);
  
  	return ret;
  }
  
  static int tcpm_pps_set_op_curr(struct tcpm_port *port, u16 op_curr)
  {
  	unsigned int target_mw;
  	int ret;
  
  	mutex_lock(&port->swap_lock);
  	mutex_lock(&port->lock);
  
  	if (!port->pps_data.active) {
  		ret = -EOPNOTSUPP;
  		goto port_unlock;
  	}
  
  	if (port->state != SNK_READY) {
  		ret = -EAGAIN;
  		goto port_unlock;
  	}
  
  	if (op_curr > port->pps_data.max_curr) {
  		ret = -EINVAL;
  		goto port_unlock;
  	}
  
  	target_mw = (op_curr * port->pps_data.out_volt) / 1000;
  	if (target_mw < port->operating_snk_mw) {
  		ret = -EINVAL;
  		goto port_unlock;
  	}
  
  	/* Round down operating current to align with PPS valid steps */
  	op_curr = op_curr - (op_curr % RDO_PROG_CURR_MA_STEP);
  
  	reinit_completion(&port->pps_complete);
  	port->pps_data.op_curr = op_curr;
  	port->pps_status = 0;
  	port->pps_pending = true;
  	tcpm_set_state(port, SNK_NEGOTIATE_PPS_CAPABILITIES, 0);
  	mutex_unlock(&port->lock);
  
  	if (!wait_for_completion_timeout(&port->pps_complete,
  				msecs_to_jiffies(PD_PPS_CTRL_TIMEOUT)))
  		ret = -ETIMEDOUT;
  	else
  		ret = port->pps_status;
  
  	goto swap_unlock;
  
  port_unlock:
  	mutex_unlock(&port->lock);
  swap_unlock:
  	mutex_unlock(&port->swap_lock);
  
  	return ret;
  }
  
  static int tcpm_pps_set_out_volt(struct tcpm_port *port, u16 out_volt)
  {
  	unsigned int target_mw;
  	int ret;
  
  	mutex_lock(&port->swap_lock);
  	mutex_lock(&port->lock);
  
  	if (!port->pps_data.active) {
  		ret = -EOPNOTSUPP;
  		goto port_unlock;
  	}
  
  	if (port->state != SNK_READY) {
  		ret = -EAGAIN;
  		goto port_unlock;
  	}
  
  	if (out_volt < port->pps_data.min_volt ||
  	    out_volt > port->pps_data.max_volt) {
  		ret = -EINVAL;
  		goto port_unlock;
  	}
  
  	target_mw = (port->pps_data.op_curr * out_volt) / 1000;
  	if (target_mw < port->operating_snk_mw) {
  		ret = -EINVAL;
  		goto port_unlock;
  	}
  
  	/* Round down output voltage to align with PPS valid steps */
  	out_volt = out_volt - (out_volt % RDO_PROG_VOLT_MV_STEP);
  
  	reinit_completion(&port->pps_complete);
  	port->pps_data.out_volt = out_volt;
  	port->pps_status = 0;
  	port->pps_pending = true;
  	tcpm_set_state(port, SNK_NEGOTIATE_PPS_CAPABILITIES, 0);
  	mutex_unlock(&port->lock);
  
  	if (!wait_for_completion_timeout(&port->pps_complete,
  				msecs_to_jiffies(PD_PPS_CTRL_TIMEOUT)))
  		ret = -ETIMEDOUT;
  	else
  		ret = port->pps_status;
  
  	goto swap_unlock;
  
  port_unlock:
  	mutex_unlock(&port->lock);
  swap_unlock:
  	mutex_unlock(&port->swap_lock);
  
  	return ret;
  }
  
  static int tcpm_pps_activate(struct tcpm_port *port, bool activate)
  {
  	int ret = 0;
  
  	mutex_lock(&port->swap_lock);
  	mutex_lock(&port->lock);
  
  	if (!port->pps_data.supported) {
  		ret = -EOPNOTSUPP;
  		goto port_unlock;
  	}
  
  	/* Trying to deactivate PPS when already deactivated so just bail */
  	if (!port->pps_data.active && !activate)
  		goto port_unlock;
  
  	if (port->state != SNK_READY) {
  		ret = -EAGAIN;
  		goto port_unlock;
  	}
  
  	reinit_completion(&port->pps_complete);
  	port->pps_status = 0;
  	port->pps_pending = true;
  
  	/* Trigger PPS request or move back to standard PDO contract */
  	if (activate) {
  		port->pps_data.out_volt = port->supply_voltage;
  		port->pps_data.op_curr = port->current_limit;
  		tcpm_set_state(port, SNK_NEGOTIATE_PPS_CAPABILITIES, 0);
  	} else {
  		tcpm_set_state(port, SNK_NEGOTIATE_CAPABILITIES, 0);
  	}
  	mutex_unlock(&port->lock);
  
  	if (!wait_for_completion_timeout(&port->pps_complete,
  				msecs_to_jiffies(PD_PPS_CTRL_TIMEOUT)))
  		ret = -ETIMEDOUT;
  	else
  		ret = port->pps_status;
  
  	goto swap_unlock;
  
  port_unlock:
  	mutex_unlock(&port->lock);
  swap_unlock:
  	mutex_unlock(&port->swap_lock);
  
  	return ret;
  }
  
  static void tcpm_init(struct tcpm_port *port)
  {
  	enum typec_cc_status cc1, cc2;
  
  	port->tcpc->init(port->tcpc);
  
  	tcpm_reset_port(port);
  
  	/*
  	 * XXX
  	 * Should possibly wait for VBUS to settle if it was enabled locally
  	 * since tcpm_reset_port() will disable VBUS.
  	 */
  	port->vbus_present = port->tcpc->get_vbus(port->tcpc);
  	if (port->vbus_present)
  		port->vbus_never_low = true;
  
  	tcpm_set_state(port, tcpm_default_state(port), 0);
  
  	if (port->tcpc->get_cc(port->tcpc, &cc1, &cc2) == 0)
  		_tcpm_cc_change(port, cc1, cc2);
  
  	/*
  	 * Some adapters need a clean slate at startup, and won't recover
  	 * otherwise. So do not try to be fancy and force a clean disconnect.
  	 */
  	tcpm_set_state(port, PORT_RESET, 0);
  }
  
  static int tcpm_port_type_set(const struct typec_capability *cap,
  			      enum typec_port_type type)
  {
  	struct tcpm_port *port = typec_cap_to_tcpm(cap);
  
  	mutex_lock(&port->lock);
  	if (type == port->port_type)
  		goto port_unlock;
  
  	port->port_type = type;
  
  	if (!port->connected) {
  		tcpm_set_state(port, PORT_RESET, 0);
  	} else if (type == TYPEC_PORT_SNK) {
  		if (!(port->pwr_role == TYPEC_SINK &&
  		      port->data_role == TYPEC_DEVICE))
  			tcpm_set_state(port, PORT_RESET, 0);
  	} else if (type == TYPEC_PORT_SRC) {
  		if (!(port->pwr_role == TYPEC_SOURCE &&
  		      port->data_role == TYPEC_HOST))
  			tcpm_set_state(port, PORT_RESET, 0);
  	}
  
  port_unlock:
  	mutex_unlock(&port->lock);
  	return 0;
  }
  
  void tcpm_tcpc_reset(struct tcpm_port *port)
  {
  	mutex_lock(&port->lock);
  	/* XXX: Maintain PD connection if possible? */
  	tcpm_init(port);
  	mutex_unlock(&port->lock);
  }
  EXPORT_SYMBOL_GPL(tcpm_tcpc_reset);
  
  static int tcpm_copy_pdos(u32 *dest_pdo, const u32 *src_pdo,
  			  unsigned int nr_pdo)
  {
  	unsigned int i;
  
  	if (nr_pdo > PDO_MAX_OBJECTS)
  		nr_pdo = PDO_MAX_OBJECTS;
  
  	for (i = 0; i < nr_pdo; i++)
  		dest_pdo[i] = src_pdo[i];
  
  	return nr_pdo;
  }
  
  static int tcpm_copy_vdos(u32 *dest_vdo, const u32 *src_vdo,
  			  unsigned int nr_vdo)
  {
  	unsigned int i;
  
  	if (nr_vdo > VDO_MAX_OBJECTS)
  		nr_vdo = VDO_MAX_OBJECTS;
  
  	for (i = 0; i < nr_vdo; i++)
  		dest_vdo[i] = src_vdo[i];
  
  	return nr_vdo;
  }
  
  static int tcpm_fw_get_caps(struct tcpm_port *port,
  			    struct fwnode_handle *fwnode)
  {
  	const char *cap_str;
  	int ret;
  	u32 mw;
  
  	if (!fwnode)
  		return -EINVAL;
  
  	/* USB data support is optional */
  	ret = fwnode_property_read_string(fwnode, "data-role", &cap_str);
  	if (ret == 0) {
  		ret = typec_find_port_data_role(cap_str);
  		if (ret < 0)
  			return ret;
  		port->typec_caps.data = ret;
  	}
  
  	ret = fwnode_property_read_string(fwnode, "power-role", &cap_str);
  	if (ret < 0)
  		return ret;
  
  	ret = typec_find_port_power_role(cap_str);
  	if (ret < 0)
  		return ret;
  	port->typec_caps.type = ret;
  	port->port_type = port->typec_caps.type;
  
  	if (port->port_type == TYPEC_PORT_SNK)
  		goto sink;
  
  	/* Get source pdos */
  	ret = fwnode_property_count_u32(fwnode, "source-pdos");
  	if (ret <= 0)
  		return -EINVAL;
  
  	port->nr_src_pdo = min(ret, PDO_MAX_OBJECTS);
  	ret = fwnode_property_read_u32_array(fwnode, "source-pdos",
  					     port->src_pdo, port->nr_src_pdo);
  	if ((ret < 0) || tcpm_validate_caps(port, port->src_pdo,
  					    port->nr_src_pdo))
  		return -EINVAL;
  
  	if (port->port_type == TYPEC_PORT_SRC)
  		return 0;
  
  	/* Get the preferred power role for DRP */
  	ret = fwnode_property_read_string(fwnode, "try-power-role", &cap_str);
  	if (ret < 0)
  		return ret;
  
  	port->typec_caps.prefer_role = typec_find_power_role(cap_str);
  	if (port->typec_caps.prefer_role < 0)
  		return -EINVAL;
  sink:
  	/* Get sink pdos */
  	ret = fwnode_property_count_u32(fwnode, "sink-pdos");
  	if (ret <= 0)
  		return -EINVAL;
  
  	port->nr_snk_pdo = min(ret, PDO_MAX_OBJECTS);
  	ret = fwnode_property_read_u32_array(fwnode, "sink-pdos",
  					     port->snk_pdo, port->nr_snk_pdo);
  	if ((ret < 0) || tcpm_validate_caps(port, port->snk_pdo,
  					    port->nr_snk_pdo))
  		return -EINVAL;
  
  	if (fwnode_property_read_u32(fwnode, "op-sink-microwatt", &mw) < 0)
  		return -EINVAL;
  	port->operating_snk_mw = mw / 1000;
  
  	port->self_powered = fwnode_property_read_bool(fwnode, "self-powered");
  
  	return 0;
  }
  
  /* Power Supply access to expose source power information */
  enum tcpm_psy_online_states {
  	TCPM_PSY_OFFLINE = 0,
  	TCPM_PSY_FIXED_ONLINE,
  	TCPM_PSY_PROG_ONLINE,
  };
  
  static enum power_supply_property tcpm_psy_props[] = {
  	POWER_SUPPLY_PROP_USB_TYPE,
  	POWER_SUPPLY_PROP_ONLINE,
  	POWER_SUPPLY_PROP_VOLTAGE_MIN,
  	POWER_SUPPLY_PROP_VOLTAGE_MAX,
  	POWER_SUPPLY_PROP_VOLTAGE_NOW,
  	POWER_SUPPLY_PROP_CURRENT_MAX,
  	POWER_SUPPLY_PROP_CURRENT_NOW,
  };
  
  static int tcpm_psy_get_online(struct tcpm_port *port,
  			       union power_supply_propval *val)
  {
  	if (port->vbus_charge) {
  		if (port->pps_data.active)
  			val->intval = TCPM_PSY_PROG_ONLINE;
  		else
  			val->intval = TCPM_PSY_FIXED_ONLINE;
  	} else {
  		val->intval = TCPM_PSY_OFFLINE;
  	}
  
  	return 0;
  }
  
  static int tcpm_psy_get_voltage_min(struct tcpm_port *port,
  				    union power_supply_propval *val)
  {
  	if (port->pps_data.active)
  		val->intval = port->pps_data.min_volt * 1000;
  	else
  		val->intval = port->supply_voltage * 1000;
  
  	return 0;
  }
  
  static int tcpm_psy_get_voltage_max(struct tcpm_port *port,
  				    union power_supply_propval *val)
  {
  	if (port->pps_data.active)
  		val->intval = port->pps_data.max_volt * 1000;
  	else
  		val->intval = port->supply_voltage * 1000;
  
  	return 0;
  }
  
  static int tcpm_psy_get_voltage_now(struct tcpm_port *port,
  				    union power_supply_propval *val)
  {
  	val->intval = port->supply_voltage * 1000;
  
  	return 0;
  }
  
  static int tcpm_psy_get_current_max(struct tcpm_port *port,
  				    union power_supply_propval *val)
  {
  	if (port->pps_data.active)
  		val->intval = port->pps_data.max_curr * 1000;
  	else
  		val->intval = port->current_limit * 1000;
  
  	return 0;
  }
  
  static int tcpm_psy_get_current_now(struct tcpm_port *port,
  				    union power_supply_propval *val)
  {
  	val->intval = port->current_limit * 1000;
  
  	return 0;
  }
  
  static int tcpm_psy_get_prop(struct power_supply *psy,
  			     enum power_supply_property psp,
  			     union power_supply_propval *val)
  {
  	struct tcpm_port *port = power_supply_get_drvdata(psy);
  	int ret = 0;
  
  	switch (psp) {
  	case POWER_SUPPLY_PROP_USB_TYPE:
  		val->intval = port->usb_type;
  		break;
  	case POWER_SUPPLY_PROP_ONLINE:
  		ret = tcpm_psy_get_online(port, val);
  		break;
  	case POWER_SUPPLY_PROP_VOLTAGE_MIN:
  		ret = tcpm_psy_get_voltage_min(port, val);
  		break;
  	case POWER_SUPPLY_PROP_VOLTAGE_MAX:
  		ret = tcpm_psy_get_voltage_max(port, val);
  		break;
  	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
  		ret = tcpm_psy_get_voltage_now(port, val);
  		break;
  	case POWER_SUPPLY_PROP_CURRENT_MAX:
  		ret = tcpm_psy_get_current_max(port, val);
  		break;
  	case POWER_SUPPLY_PROP_CURRENT_NOW:
  		ret = tcpm_psy_get_current_now(port, val);
  		break;
  	default:
  		ret = -EINVAL;
  		break;
  	}
  
  	return ret;
  }
  
  static int tcpm_psy_set_online(struct tcpm_port *port,
  			       const union power_supply_propval *val)
  {
  	int ret;
  
  	switch (val->intval) {
  	case TCPM_PSY_FIXED_ONLINE:
  		ret = tcpm_pps_activate(port, false);
  		break;
  	case TCPM_PSY_PROG_ONLINE:
  		ret = tcpm_pps_activate(port, true);
  		break;
  	default:
  		ret = -EINVAL;
  		break;
  	}
  
  	return ret;
  }
  
  static int tcpm_psy_set_prop(struct power_supply *psy,
  			     enum power_supply_property psp,
  			     const union power_supply_propval *val)
  {
  	struct tcpm_port *port = power_supply_get_drvdata(psy);
  	int ret;
  
  	switch (psp) {
  	case POWER_SUPPLY_PROP_ONLINE:
  		ret = tcpm_psy_set_online(port, val);
  		break;
  	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
  		if (val->intval < port->pps_data.min_volt * 1000 ||
  		    val->intval > port->pps_data.max_volt * 1000)
  			ret = -EINVAL;
  		else
  			ret = tcpm_pps_set_out_volt(port, val->intval / 1000);
  		break;
  	case POWER_SUPPLY_PROP_CURRENT_NOW:
  		if (val->intval > port->pps_data.max_curr * 1000)
  			ret = -EINVAL;
  		else
  			ret = tcpm_pps_set_op_curr(port, val->intval / 1000);
  		break;
  	default:
  		ret = -EINVAL;
  		break;
  	}
  
  	return ret;
  }
  
  static int tcpm_psy_prop_writeable(struct power_supply *psy,
  				   enum power_supply_property psp)
  {
  	switch (psp) {
  	case POWER_SUPPLY_PROP_ONLINE:
  	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
  	case POWER_SUPPLY_PROP_CURRENT_NOW:
  		return 1;
  	default:
  		return 0;
  	}
  }
  
  static enum power_supply_usb_type tcpm_psy_usb_types[] = {
  	POWER_SUPPLY_USB_TYPE_C,
  	POWER_SUPPLY_USB_TYPE_PD,
  	POWER_SUPPLY_USB_TYPE_PD_PPS,
  };
  
  static const char *tcpm_psy_name_prefix = "tcpm-source-psy-";
  
  static int devm_tcpm_psy_register(struct tcpm_port *port)
  {
  	struct power_supply_config psy_cfg = {};
  	const char *port_dev_name = dev_name(port->dev);
  	size_t psy_name_len = strlen(tcpm_psy_name_prefix) +
  				     strlen(port_dev_name) + 1;
  	char *psy_name;
  
  	psy_cfg.drv_data = port;
  	psy_cfg.fwnode = dev_fwnode(port->dev);
  	psy_name = devm_kzalloc(port->dev, psy_name_len, GFP_KERNEL);
  	if (!psy_name)
  		return -ENOMEM;
  
  	snprintf(psy_name, psy_name_len, "%s%s", tcpm_psy_name_prefix,
  		 port_dev_name);
  	port->psy_desc.name = psy_name;
  	port->psy_desc.type = POWER_SUPPLY_TYPE_USB,
  	port->psy_desc.usb_types = tcpm_psy_usb_types;
  	port->psy_desc.num_usb_types = ARRAY_SIZE(tcpm_psy_usb_types);
  	port->psy_desc.properties = tcpm_psy_props,
  	port->psy_desc.num_properties = ARRAY_SIZE(tcpm_psy_props),
  	port->psy_desc.get_property = tcpm_psy_get_prop,
  	port->psy_desc.set_property = tcpm_psy_set_prop,
  	port->psy_desc.property_is_writeable = tcpm_psy_prop_writeable,
  
  	port->usb_type = POWER_SUPPLY_USB_TYPE_C;
  
  	port->psy = devm_power_supply_register(port->dev, &port->psy_desc,
  					       &psy_cfg);
  
  	return PTR_ERR_OR_ZERO(port->psy);
  }
  
  static int tcpm_copy_caps(struct tcpm_port *port,
  			  const struct tcpc_config *tcfg)
  {
  	if (tcpm_validate_caps(port, tcfg->src_pdo, tcfg->nr_src_pdo) ||
  	    tcpm_validate_caps(port, tcfg->snk_pdo, tcfg->nr_snk_pdo))
  		return -EINVAL;
  
  	port->nr_src_pdo = tcpm_copy_pdos(port->src_pdo, tcfg->src_pdo,
  					  tcfg->nr_src_pdo);
  	port->nr_snk_pdo = tcpm_copy_pdos(port->snk_pdo, tcfg->snk_pdo,
  					  tcfg->nr_snk_pdo);
  
  	port->nr_snk_vdo = tcpm_copy_vdos(port->snk_vdo, tcfg->snk_vdo,
  					  tcfg->nr_snk_vdo);
  
  	port->operating_snk_mw = tcfg->operating_snk_mw;
  
  	port->typec_caps.prefer_role = tcfg->default_role;
  	port->typec_caps.type = tcfg->type;
  	port->typec_caps.data = tcfg->data;
  	port->self_powered = tcfg->self_powered;
  
  	return 0;
  }
  
  struct tcpm_port *tcpm_register_port(struct device *dev, struct tcpc_dev *tcpc)
  {
  	struct tcpm_port *port;
  	int i, err;
  
  	if (!dev || !tcpc ||
  	    !tcpc->get_vbus || !tcpc->set_cc || !tcpc->get_cc ||
  	    !tcpc->set_polarity || !tcpc->set_vconn || !tcpc->set_vbus ||
  	    !tcpc->set_pd_rx || !tcpc->set_roles || !tcpc->pd_transmit)
  		return ERR_PTR(-EINVAL);
  
  	port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
  	if (!port)
  		return ERR_PTR(-ENOMEM);
  
  	port->dev = dev;
  	port->tcpc = tcpc;
  
  	mutex_init(&port->lock);
  	mutex_init(&port->swap_lock);
  
  	port->wq = create_singlethread_workqueue(dev_name(dev));
  	if (!port->wq)
  		return ERR_PTR(-ENOMEM);
  	INIT_DELAYED_WORK(&port->state_machine, tcpm_state_machine_work);
  	INIT_DELAYED_WORK(&port->vdm_state_machine, vdm_state_machine_work);
  	INIT_WORK(&port->event_work, tcpm_pd_event_handler);
  
  	spin_lock_init(&port->pd_event_lock);
  
  	init_completion(&port->tx_complete);
  	init_completion(&port->swap_complete);
  	init_completion(&port->pps_complete);
  	tcpm_debugfs_init(port);
  
  	err = tcpm_fw_get_caps(port, tcpc->fwnode);
  	if ((err < 0) && tcpc->config)
  		err = tcpm_copy_caps(port, tcpc->config);
  	if (err < 0)
  		goto out_destroy_wq;
  
  	if (!tcpc->config || !tcpc->config->try_role_hw)
  		port->try_role = port->typec_caps.prefer_role;
  	else
  		port->try_role = TYPEC_NO_PREFERRED_ROLE;
  
  	port->typec_caps.fwnode = tcpc->fwnode;
  	port->typec_caps.revision = 0x0120;	/* Type-C spec release 1.2 */
  	port->typec_caps.pd_revision = 0x0300;	/* USB-PD spec release 3.0 */
  	port->typec_caps.dr_set = tcpm_dr_set;
  	port->typec_caps.pr_set = tcpm_pr_set;
  	port->typec_caps.vconn_set = tcpm_vconn_set;
  	port->typec_caps.try_role = tcpm_try_role;
  	port->typec_caps.port_type_set = tcpm_port_type_set;
  
  	port->partner_desc.identity = &port->partner_ident;
  	port->port_type = port->typec_caps.type;
  
  	port->role_sw = usb_role_switch_get(port->dev);
  	if (IS_ERR(port->role_sw)) {
  		err = PTR_ERR(port->role_sw);
  		goto out_destroy_wq;
  	}
  
  	err = devm_tcpm_psy_register(port);
  	if (err)
  		goto out_role_sw_put;
  
  	port->typec_port = typec_register_port(port->dev, &port->typec_caps);
  	if (IS_ERR(port->typec_port)) {
  		err = PTR_ERR(port->typec_port);
  		goto out_role_sw_put;
  	}
  
  	if (tcpc->config && tcpc->config->alt_modes) {
  		const struct typec_altmode_desc *paltmode = tcpc->config->alt_modes;
  
  		i = 0;
  		while (paltmode->svid && i < ARRAY_SIZE(port->port_altmode)) {
  			struct typec_altmode *alt;
  
  			alt = typec_port_register_altmode(port->typec_port,
  							  paltmode);
  			if (IS_ERR(alt)) {
  				tcpm_log(port,
  					 "%s: failed to register port alternate mode 0x%x",
  					 dev_name(dev), paltmode->svid);
  				break;
  			}
  			typec_altmode_set_drvdata(alt, port);
  			alt->ops = &tcpm_altmode_ops;
  			port->port_altmode[i] = alt;
  			i++;
  			paltmode++;
  		}
  	}
  
  	mutex_lock(&port->lock);
  	tcpm_init(port);
  	mutex_unlock(&port->lock);
  
  	tcpm_log(port, "%s: registered", dev_name(dev));
  	return port;
  
  out_role_sw_put:
  	usb_role_switch_put(port->role_sw);
  out_destroy_wq:
  	tcpm_debugfs_exit(port);
  	destroy_workqueue(port->wq);
  	return ERR_PTR(err);
  }
  EXPORT_SYMBOL_GPL(tcpm_register_port);
  
  void tcpm_unregister_port(struct tcpm_port *port)
  {
  	int i;
  
  	tcpm_reset_port(port);
  	for (i = 0; i < ARRAY_SIZE(port->port_altmode); i++)
  		typec_unregister_altmode(port->port_altmode[i]);
  	typec_unregister_port(port->typec_port);
  	usb_role_switch_put(port->role_sw);
  	tcpm_debugfs_exit(port);
  	destroy_workqueue(port->wq);
  }
  EXPORT_SYMBOL_GPL(tcpm_unregister_port);
  
  MODULE_AUTHOR("Guenter Roeck <groeck@chromium.org>");
  MODULE_DESCRIPTION("USB Type-C Port Manager");
  MODULE_LICENSE("GPL");
  