text: /* SPDX-License-Identifier: GPL-2.0-only */
  /*
   *  Shared Transport Header file
   *	To be included by the protocol stack drivers for
   *	Texas Instruments BT,FM and GPS combo chip drivers
   *	and also serves the sub-modules of the shared transport driver.
   *
   *  Copyright (C) 2009-2010 Texas Instruments
   *  Author: Pavan Savoy <pavan_savoy@ti.com>
   */
  
  #ifndef TI_WILINK_ST_H
  #define TI_WILINK_ST_H
  
  #include <linux/skbuff.h>
  
  /**
   * enum proto-type - The protocol on WiLink chips which share a
   *	common physical interface like UART.
   */
  enum proto_type {
  	ST_BT,
  	ST_FM,
  	ST_GPS,
  	ST_MAX_CHANNELS = 16,
  };
  
  /**
   * struct st_proto_s - Per Protocol structure from BT/FM/GPS to ST
   * @type: type of the protocol being registered among the
   *	available proto_type(BT, FM, GPS the protocol which share TTY).
   * @recv: the receiver callback pointing to a function in the
   *	protocol drivers called by the ST driver upon receiving
   *	relevant data.
   * @match_packet: reserved for future use, to make ST more generic
   * @reg_complete_cb: callback handler pointing to a function in protocol
   *	handler called by ST when the pending registrations are complete.
   *	The registrations are marked pending, in situations when fw
   *	download is in progress.
   * @write: pointer to function in ST provided to protocol drivers from ST,
   *	to be made use when protocol drivers have data to send to TTY.
   * @priv_data: privdate data holder for the protocol drivers, sent
   *	from the protocol drivers during registration, and sent back on
   *	reg_complete_cb and recv.
   * @chnl_id: channel id the protocol driver is interested in, the channel
   *	id is nothing but the 1st byte of the packet in UART frame.
   * @max_frame_size: size of the largest frame the protocol can receive.
   * @hdr_len: length of the header structure of the protocol.
   * @offset_len_in_hdr: this provides the offset of the length field in the
   *	header structure of the protocol header, to assist ST to know
   *	how much to receive, if the data is split across UART frames.
   * @len_size: whether the length field inside the header is 2 bytes
   *	or 1 byte.
   * @reserve: the number of bytes ST needs to reserve in the skb being
   *	prepared for the protocol driver.
   */
  struct st_proto_s {
  	enum proto_type type;
  	long (*recv) (void *, struct sk_buff *);
  	unsigned char (*match_packet) (const unsigned char *data);
  	void (*reg_complete_cb) (void *, int data);
  	long (*write) (struct sk_buff *skb);
  	void *priv_data;
  
  	unsigned char chnl_id;
  	unsigned short max_frame_size;
  	unsigned char hdr_len;
  	unsigned char offset_len_in_hdr;
  	unsigned char len_size;
  	unsigned char reserve;
  };
  
  extern long st_register(struct st_proto_s *);
  extern long st_unregister(struct st_proto_s *);
  
  
  /*
   * header information used by st_core.c
   */
  
  /* states of protocol list */
  #define ST_NOTEMPTY	1
  #define ST_EMPTY	0
  
  /*
   * possible st_states
   */
  #define ST_INITIALIZING		1
  #define ST_REG_IN_PROGRESS	2
  #define ST_REG_PENDING		3
  #define ST_WAITING_FOR_RESP	4
  
  /**
   * struct st_data_s - ST core internal structure
   * @st_state: different states of ST like initializing, registration
   *	in progress, this is mainly used to return relevant err codes
   *	when protocol drivers are registering. It is also used to track
   *	the recv function, as in during fw download only HCI events
   *	can occur , where as during other times other events CH8, CH9
   *	can occur.
   * @tty: tty provided by the TTY core for line disciplines.
   * @tx_skb: If for some reason the tty's write returns lesser bytes written
   *	then to maintain the rest of data to be written on next instance.
   *	This needs to be protected, hence the lock inside wakeup func.
   * @tx_state: if the data is being written onto the TTY and protocol driver
   *	wants to send more, queue up data and mark that there is
   *	more data to send.
   * @list: the list of protocols registered, only MAX can exist, one protocol
   *	can register only once.
   * @rx_state: states to be maintained inside st's tty receive
   * @rx_count: count to be maintained inside st's tty receieve
   * @rx_skb: the skb where all data for a protocol gets accumulated,
   *	since tty might not call receive when a complete event packet
   *	is received, the states, count and the skb needs to be maintained.
   * @rx_chnl: the channel ID for which the data is getting accumalated for.
   * @txq: the list of skbs which needs to be sent onto the TTY.
   * @tx_waitq: if the chip is not in AWAKE state, the skbs needs to be queued
   *	up in here, PM(WAKEUP_IND) data needs to be sent and then the skbs
   *	from waitq can be moved onto the txq.
   *	Needs locking too.
   * @lock: the lock to protect skbs, queues, and ST states.
   * @protos_registered: count of the protocols registered, also when 0 the
   *	chip enable gpio can be toggled, and when it changes to 1 the fw
   *	needs to be downloaded to initialize chip side ST.
   * @ll_state: the various PM states the chip can be, the states are notified
   *	to us, when the chip sends relevant PM packets(SLEEP_IND, WAKE_IND).
   * @kim_data: reference to the parent encapsulating structure.
   *
   */
  struct st_data_s {
  	unsigned long st_state;
  	struct sk_buff *tx_skb;
  #define ST_TX_SENDING	1
  #define ST_TX_WAKEUP	2
  	unsigned long tx_state;
  	struct st_proto_s *list[ST_MAX_CHANNELS];
  	bool is_registered[ST_MAX_CHANNELS];
  	unsigned long rx_state;
  	unsigned long rx_count;
  	struct sk_buff *rx_skb;
  	unsigned char rx_chnl;
  	struct sk_buff_head txq, tx_waitq;
  	spinlock_t lock;
  	unsigned char	protos_registered;
  	unsigned long ll_state;
  	void *kim_data;
  	struct tty_struct *tty;
  	struct work_struct work_write_wakeup;
  };
  
  /*
   * wrapper around tty->ops->write_room to check
   * availability during firmware download
   */
  int st_get_uart_wr_room(struct st_data_s *st_gdata);
  /**
   * st_int_write -
   * point this to tty->driver->write or tty->ops->write
   * depending upon the kernel version
   */
  int st_int_write(struct st_data_s*, const unsigned char*, int);
  
  /**
   * st_write -
   * internal write function, passed onto protocol drivers
   * via the write function ptr of protocol struct
   */
  long st_write(struct sk_buff *);
  
  /* function to be called from ST-LL */
  void st_ll_send_frame(enum proto_type, struct sk_buff *);
  
  /* internal wake up function */
  void st_tx_wakeup(struct st_data_s *st_data);
  
  /* init, exit entry funcs called from KIM */
  int st_core_init(struct st_data_s **);
  void st_core_exit(struct st_data_s *);
  
  /* ask for reference from KIM */
  void st_kim_ref(struct st_data_s **, int);
  
  #define GPS_STUB_TEST
  #ifdef GPS_STUB_TEST
  int gps_chrdrv_stub_write(const unsigned char*, int);
  void gps_chrdrv_stub_init(void);
  #endif
  
  /*
   * header information used by st_kim.c
   */
  
  /* time in msec to wait for
   * line discipline to be installed
   */
  #define LDISC_TIME	1000
  #define CMD_RESP_TIME	800
  #define CMD_WR_TIME	5000
  #define MAKEWORD(a, b)  ((unsigned short)(((unsigned char)(a)) \
  	| ((unsigned short)((unsigned char)(b))) << 8))
  
  #define GPIO_HIGH 1
  #define GPIO_LOW  0
  
  /* the Power-On-Reset logic, requires to attempt
   * to download firmware onto chip more than once
   * since the self-test for chip takes a while
   */
  #define POR_RETRY_COUNT 5
  
  /**
   * struct chip_version - save the chip version
   */
  struct chip_version {
  	unsigned short full;
  	unsigned short chip;
  	unsigned short min_ver;
  	unsigned short maj_ver;
  };
  
  #define UART_DEV_NAME_LEN 32
  /**
   * struct kim_data_s - the KIM internal data, embedded as the
   *	platform's drv data. One for each ST device in the system.
   * @uim_pid: KIM needs to communicate with UIM to request to install
   *	the ldisc by opening UART when protocol drivers register.
   * @kim_pdev: the platform device added in one of the board-XX.c file
   *	in arch/XX/ directory, 1 for each ST device.
   * @kim_rcvd: completion handler to notify when data was received,
   *	mainly used during fw download, which involves multiple send/wait
   *	for each of the HCI-VS commands.
   * @ldisc_installed: completion handler to notify that the UIM accepted
   *	the request to install ldisc, notify from tty_open which suggests
   *	the ldisc was properly installed.
   * @resp_buffer: data buffer for the .bts fw file name.
   * @fw_entry: firmware class struct to request/release the fw.
   * @rx_state: the rx state for kim's receive func during fw download.
   * @rx_count: the rx count for the kim's receive func during fw download.
   * @rx_skb: all of fw data might not come at once, and hence data storage for
   *	whole of the fw response, only HCI_EVENTs and hence diff from ST's
   *	response.
   * @core_data: ST core's data, which mainly is the tty's disc_data
   * @version: chip version available via a sysfs entry.
   *
   */
  struct kim_data_s {
  	long uim_pid;
  	struct platform_device *kim_pdev;
  	struct completion kim_rcvd, ldisc_installed;
  	char resp_buffer[30];
  	const struct firmware *fw_entry;
  	unsigned nshutdown;
  	unsigned long rx_state;
  	unsigned long rx_count;
  	struct sk_buff *rx_skb;
  	struct st_data_s *core_data;
  	struct chip_version version;
  	unsigned char ldisc_install;
  	unsigned char dev_name[UART_DEV_NAME_LEN + 1];
  	unsigned flow_cntrl;
  	unsigned baud_rate;
  };
  
  /**
   * functions called when 1 of the protocol drivers gets
   * registered, these need to communicate with UIM to request
   * ldisc installed, read chip_version, download relevant fw
   */
  long st_kim_start(void *);
  long st_kim_stop(void *);
  
  void st_kim_complete(void *);
  void kim_st_list_protocols(struct st_data_s *, void *);
  void st_kim_recv(void *, const unsigned char *, long);
  
  
  /*
   * BTS headers
   */
  #define ACTION_SEND_COMMAND     1
  #define ACTION_WAIT_EVENT       2
  #define ACTION_SERIAL           3
  #define ACTION_DELAY            4
  #define ACTION_RUN_SCRIPT       5
  #define ACTION_REMARKS          6
  
  /**
   * struct bts_header - the fw file is NOT binary which can
   *	be sent onto TTY as is. The .bts is more a script
   *	file which has different types of actions.
   *	Each such action needs to be parsed by the KIM and
   *	relevant procedure to be called.
   */
  struct bts_header {
  	u32 magic;
  	u32 version;
  	u8 future[24];
  	u8 actions[];
  } __attribute__ ((packed));
  
  /**
   * struct bts_action - Each .bts action has its own type of
   *	data.
   */
  struct bts_action {
  	u16 type;
  	u16 size;
  	u8 data[];
  } __attribute__ ((packed));
  
  struct bts_action_send {
  	u8 data[0];
  } __attribute__ ((packed));
  
  struct bts_action_wait {
  	u32 msec;
  	u32 size;
  	u8 data[];
  } __attribute__ ((packed));
  
  struct bts_action_delay {
  	u32 msec;
  } __attribute__ ((packed));
  
  struct bts_action_serial {
  	u32 baud;
  	u32 flow_control;
  } __attribute__ ((packed));
  
  /**
   * struct hci_command - the HCI-VS for intrepreting
   *	the change baud rate of host-side UART, which
   *	needs to be ignored, since UIM would do that
   *	when it receives request from KIM for ldisc installation.
   */
  struct hci_command {
  	u8 prefix;
  	u16 opcode;
  	u8 plen;
  	u32 speed;
  } __attribute__ ((packed));
  
  /*
   * header information used by st_ll.c
   */
  
  /* ST LL receiver states */
  #define ST_W4_PACKET_TYPE       0
  #define ST_W4_HEADER		1
  #define ST_W4_DATA		2
  
  /* ST LL state machines */
  #define ST_LL_ASLEEP               0
  #define ST_LL_ASLEEP_TO_AWAKE      1
  #define ST_LL_AWAKE                2
  #define ST_LL_AWAKE_TO_ASLEEP      3
  #define ST_LL_INVALID		   4
  
  /* different PM notifications coming from chip */
  #define LL_SLEEP_IND	0x30
  #define LL_SLEEP_ACK	0x31
  #define LL_WAKE_UP_IND	0x32
  #define LL_WAKE_UP_ACK	0x33
  
  /* initialize and de-init ST LL */
  long st_ll_init(struct st_data_s *);
  long st_ll_deinit(struct st_data_s *);
  
  /**
   * enable/disable ST LL along with KIM start/stop
   * called by ST Core
   */
  void st_ll_enable(struct st_data_s *);
  void st_ll_disable(struct st_data_s *);
  
  /**
   * various funcs used by ST core to set/get the various PM states
   * of the chip.
   */
  unsigned long st_ll_getstate(struct st_data_s *);
  unsigned long st_ll_sleep_state(struct st_data_s *, unsigned char);
  void st_ll_wakeup(struct st_data_s *);
  
  /*
   * header information used by st_core.c for FM and GPS
   * packet parsing, the bluetooth headers are already available
   * at net/bluetooth/
   */
  
  struct fm_event_hdr {
  	u8 plen;
  } __attribute__ ((packed));
  
  #define FM_MAX_FRAME_SIZE 0xFF	/* TODO: */
  #define FM_EVENT_HDR_SIZE 1	/* size of fm_event_hdr */
  #define ST_FM_CH8_PKT 0x8
  
  /* gps stuff */
  struct gps_event_hdr {
  	u8 opcode;
  	u16 plen;
  } __attribute__ ((packed));
  
  /**
   * struct ti_st_plat_data - platform data shared between ST driver and
   *	platform specific board file which adds the ST device.
   * @nshutdown_gpio: Host's GPIO line to which chip's BT_EN is connected.
   * @dev_name: The UART/TTY name to which chip is interfaced. (eg: /dev/ttyS1)
   * @flow_cntrl: Should always be 1, since UART's CTS/RTS is used for PM
   *	purposes.
   * @baud_rate: The baud rate supported by the Host UART controller, this will
   *	be shared across with the chip via a HCI VS command from User-Space Init
   *	Mgr application.
   * @suspend:
   * @resume: legacy PM routines hooked to platform specific board file, so as
   *	to take chip-host interface specific action.
   * @chip_enable:
   * @chip_disable: Platform/Interface specific mux mode setting, GPIO
   *	configuring, Host side PM disabling etc.. can be done here.
   * @chip_asleep:
   * @chip_awake: Chip specific deep sleep states is communicated to Host
   *	specific board-xx.c to take actions such as cut UART clocks when chip
   *	asleep or run host faster when chip awake etc..
   *
   */
  struct ti_st_plat_data {
  	u32 nshutdown_gpio;
  	unsigned char dev_name[UART_DEV_NAME_LEN]; /* uart name */
  	u32 flow_cntrl; /* flow control flag */
  	u32 baud_rate;
  	int (*suspend)(struct platform_device *, pm_message_t);
  	int (*resume)(struct platform_device *);
  	int (*chip_enable) (struct kim_data_s *);
  	int (*chip_disable) (struct kim_data_s *);
  	int (*chip_asleep) (struct kim_data_s *);
  	int (*chip_awake) (struct kim_data_s *);
  };
  
  #endif /* TI_WILINK_ST_H */
  