1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * System Trace Module (STM) infrastructure
4  * Copyright (c) 2014, Intel Corporation.
5  *
6  * STM class implements generic infrastructure for  System Trace Module devices
7  * as defined in MIPI STPv2 specification.
8  */
9 
10 #ifndef _STM_STM_H_
11 #define _STM_STM_H_
12 
13 #include <linux/configfs.h>
14 
15 struct stp_policy;
16 struct stp_policy_node;
17 struct stm_protocol_driver;
18 
19 int stp_configfs_init(void);
20 void stp_configfs_exit(void);
21 
22 void *stp_policy_node_priv(struct stp_policy_node *pn);
23 
24 struct stp_master {
25 	unsigned int	nr_free;
26 	unsigned long	chan_map[];
27 };
28 
29 struct stm_device {
30 	struct device		dev;
31 	struct module		*owner;
32 	struct stp_policy	*policy;
33 	struct mutex		policy_mutex;
34 	int			major;
35 	unsigned int		sw_nmasters;
36 	struct stm_data		*data;
37 	struct mutex		link_mutex;
38 	spinlock_t		link_lock;
39 	struct list_head	link_list;
40 	/* framing protocol in use */
41 	const struct stm_protocol_driver	*pdrv;
42 	const struct config_item_type		*pdrv_node_type;
43 	/* master allocation */
44 	spinlock_t		mc_lock;
45 	struct stp_master	*masters[];
46 };
47 
48 #define to_stm_device(_d)				\
49 	container_of((_d), struct stm_device, dev)
50 
51 struct stp_policy_node *
52 stp_policy_node_lookup(struct stm_device *stm, char *s);
53 void stp_policy_node_put(struct stp_policy_node *policy_node);
54 void stp_policy_unbind(struct stp_policy *policy);
55 
56 void stp_policy_node_get_ranges(struct stp_policy_node *policy_node,
57 				unsigned int *mstart, unsigned int *mend,
58 				unsigned int *cstart, unsigned int *cend);
59 
60 const struct config_item_type *
61 get_policy_node_type(struct configfs_attribute **attrs);
62 
63 struct stm_output {
64 	spinlock_t		lock;
65 	unsigned int		master;
66 	unsigned int		channel;
67 	unsigned int		nr_chans;
68 	void			*pdrv_private;
69 };
70 
71 struct stm_file {
72 	struct stm_device	*stm;
73 	struct stm_output	output;
74 };
75 
76 struct stm_device *stm_find_device(const char *name);
77 void stm_put_device(struct stm_device *stm);
78 
79 struct stm_source_device {
80 	struct device		dev;
81 	struct stm_source_data	*data;
82 	spinlock_t		link_lock;
83 	struct stm_device __rcu	*link;
84 	struct list_head	link_entry;
85 	/* one output per stm_source device */
86 	struct stm_output	output;
87 };
88 
89 #define to_stm_source_device(_d)				\
90 	container_of((_d), struct stm_source_device, dev)
91 
92 void *to_pdrv_policy_node(struct config_item *item);
93 
94 struct stm_protocol_driver {
95 	struct module	*owner;
96 	const char	*name;
97 	ssize_t		(*write)(struct stm_data *data,
98 				 struct stm_output *output, unsigned int chan,
99 				 const char *buf, size_t count, struct stm_source_data *source);
100 	void		(*policy_node_init)(void *arg);
101 	int		(*output_open)(void *priv, struct stm_output *output);
102 	void		(*output_close)(struct stm_output *output);
103 	ssize_t		priv_sz;
104 	struct configfs_attribute	**policy_attr;
105 };
106 
107 int stm_register_protocol(const struct stm_protocol_driver *pdrv);
108 void stm_unregister_protocol(const struct stm_protocol_driver *pdrv);
109 int stm_lookup_protocol(const char *name,
110 			const struct stm_protocol_driver **pdrv,
111 			const struct config_item_type **type);
112 void stm_put_protocol(const struct stm_protocol_driver *pdrv);
113 ssize_t stm_data_write(struct stm_data *data, unsigned int m,
114 		       unsigned int c, bool ts_first, const void *buf,
115 		       size_t count);
116 
117 #endif /* _STM_STM_H_ */
118