text: /* SPDX-License-Identifier: GPL-2.0 */
  /*
   * System Trace Module (STM) infrastructure
   * Copyright (c) 2014, Intel Corporation.
   *
   * STM class implements generic infrastructure for  System Trace Module devices
   * as defined in MIPI STPv2 specification.
   */
  
  #ifndef _STM_STM_H_
  #define _STM_STM_H_
  
  #include <linux/configfs.h>
  
  struct stp_policy;
  struct stp_policy_node;
  struct stm_protocol_driver;
  
  int stp_configfs_init(void);
  void stp_configfs_exit(void);
  
  void *stp_policy_node_priv(struct stp_policy_node *pn);
  
  struct stp_master {
  	unsigned int	nr_free;
  	unsigned long	chan_map[0];
  };
  
  struct stm_device {
  	struct device		dev;
  	struct module		*owner;
  	struct stp_policy	*policy;
  	struct mutex		policy_mutex;
  	int			major;
  	unsigned int		sw_nmasters;
  	struct stm_data		*data;
  	struct mutex		link_mutex;
  	spinlock_t		link_lock;
  	struct list_head	link_list;
  	/* framing protocol in use */
  	const struct stm_protocol_driver	*pdrv;
  	const struct config_item_type		*pdrv_node_type;
  	/* master allocation */
  	spinlock_t		mc_lock;
  	struct stp_master	*masters[0];
  };
  
  #define to_stm_device(_d)				\
  	container_of((_d), struct stm_device, dev)
  
  struct stp_policy_node *
  stp_policy_node_lookup(struct stm_device *stm, char *s);
  void stp_policy_node_put(struct stp_policy_node *policy_node);
  void stp_policy_unbind(struct stp_policy *policy);
  
  void stp_policy_node_get_ranges(struct stp_policy_node *policy_node,
  				unsigned int *mstart, unsigned int *mend,
  				unsigned int *cstart, unsigned int *cend);
  
  const struct config_item_type *
  get_policy_node_type(struct configfs_attribute **attrs);
  
  struct stm_output {
  	spinlock_t		lock;
  	unsigned int		master;
  	unsigned int		channel;
  	unsigned int		nr_chans;
  	void			*pdrv_private;
  };
  
  struct stm_file {
  	struct stm_device	*stm;
  	struct stm_output	output;
  };
  
  struct stm_device *stm_find_device(const char *name);
  void stm_put_device(struct stm_device *stm);
  
  struct stm_source_device {
  	struct device		dev;
  	struct stm_source_data	*data;
  	spinlock_t		link_lock;
  	struct stm_device __rcu	*link;
  	struct list_head	link_entry;
  	/* one output per stm_source device */
  	struct stm_output	output;
  };
  
  #define to_stm_source_device(_d)				\
  	container_of((_d), struct stm_source_device, dev)
  
  void *to_pdrv_policy_node(struct config_item *item);
  
  struct stm_protocol_driver {
  	struct module	*owner;
  	const char	*name;
  	ssize_t		(*write)(struct stm_data *data,
  				 struct stm_output *output, unsigned int chan,
  				 const char *buf, size_t count);
  	void		(*policy_node_init)(void *arg);
  	int		(*output_open)(void *priv, struct stm_output *output);
  	void		(*output_close)(struct stm_output *output);
  	ssize_t		priv_sz;
  	struct configfs_attribute	**policy_attr;
  };
  
  int stm_register_protocol(const struct stm_protocol_driver *pdrv);
  void stm_unregister_protocol(const struct stm_protocol_driver *pdrv);
  int stm_lookup_protocol(const char *name,
  			const struct stm_protocol_driver **pdrv,
  			const struct config_item_type **type);
  void stm_put_protocol(const struct stm_protocol_driver *pdrv);
  ssize_t stm_data_write(struct stm_data *data, unsigned int m,
  		       unsigned int c, bool ts_first, const void *buf,
  		       size_t count);
  
  #endif /* _STM_STM_H_ */
  