xref: /openbmc/linux/include/sound/i2c.h (revision feac8c8b)
1 #ifndef __SOUND_I2C_H
2 #define __SOUND_I2C_H
3 
4 /*
5  *
6  *
7  *   This program is free software; you can redistribute it and/or modify
8  *   it under the terms of the GNU General Public License as published by
9  *   the Free Software Foundation; either version 2 of the License, or
10  *   (at your option) any later version.
11  *
12  *   This program is distributed in the hope that it will be useful,
13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *   GNU General Public License for more details.
16  *
17  *   You should have received a copy of the GNU General Public License
18  *   along with this program; if not, write to the Free Software
19  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
20  *
21  *
22  */
23 
24 #define SND_I2C_DEVICE_ADDRTEN	(1<<0)	/* 10-bit I2C address */
25 
26 struct snd_i2c_device {
27 	struct list_head list;
28 	struct snd_i2c_bus *bus;	/* I2C bus */
29 	char name[32];		/* some useful device name */
30 	unsigned short flags;	/* device flags */
31 	unsigned short addr;	/* device address (might be 10-bit) */
32 	unsigned long private_value;
33 	void *private_data;
34 	void (*private_free)(struct snd_i2c_device *device);
35 };
36 
37 #define snd_i2c_device(n) list_entry(n, struct snd_i2c_device, list)
38 
39 struct snd_i2c_bit_ops {
40 	void (*start)(struct snd_i2c_bus *bus);	/* transfer start */
41 	void (*stop)(struct snd_i2c_bus *bus);	/* transfer stop */
42 	void (*direction)(struct snd_i2c_bus *bus, int clock, int data);  /* set line direction (0 = write, 1 = read) */
43 	void (*setlines)(struct snd_i2c_bus *bus, int clock, int data);
44 	int (*getclock)(struct snd_i2c_bus *bus);
45 	int (*getdata)(struct snd_i2c_bus *bus, int ack);
46 };
47 
48 struct snd_i2c_ops {
49 	int (*sendbytes)(struct snd_i2c_device *device, unsigned char *bytes, int count);
50 	int (*readbytes)(struct snd_i2c_device *device, unsigned char *bytes, int count);
51 	int (*probeaddr)(struct snd_i2c_bus *bus, unsigned short addr);
52 };
53 
54 struct snd_i2c_bus {
55 	struct snd_card *card;	/* card which I2C belongs to */
56 	char name[32];		/* some useful label */
57 
58 	struct mutex lock_mutex;
59 
60 	struct snd_i2c_bus *master;	/* master bus when SCK/SCL is shared */
61 	struct list_head buses;	/* master: slave buses sharing SCK/SCL, slave: link list */
62 
63 	struct list_head devices; /* attached devices to this bus */
64 
65 	union {
66 		struct snd_i2c_bit_ops *bit;
67 		void *ops;
68 	} hw_ops;		/* lowlevel operations */
69 	const struct snd_i2c_ops *ops;	/* midlevel operations */
70 
71 	unsigned long private_value;
72 	void *private_data;
73 	void (*private_free)(struct snd_i2c_bus *bus);
74 };
75 
76 #define snd_i2c_slave_bus(n) list_entry(n, struct snd_i2c_bus, buses)
77 
78 int snd_i2c_bus_create(struct snd_card *card, const char *name,
79 		       struct snd_i2c_bus *master, struct snd_i2c_bus **ri2c);
80 int snd_i2c_device_create(struct snd_i2c_bus *bus, const char *name,
81 			  unsigned char addr, struct snd_i2c_device **rdevice);
82 int snd_i2c_device_free(struct snd_i2c_device *device);
83 
84 static inline void snd_i2c_lock(struct snd_i2c_bus *bus)
85 {
86 	if (bus->master)
87 		mutex_lock(&bus->master->lock_mutex);
88 	else
89 		mutex_lock(&bus->lock_mutex);
90 }
91 
92 static inline void snd_i2c_unlock(struct snd_i2c_bus *bus)
93 {
94 	if (bus->master)
95 		mutex_unlock(&bus->master->lock_mutex);
96 	else
97 		mutex_unlock(&bus->lock_mutex);
98 }
99 
100 int snd_i2c_sendbytes(struct snd_i2c_device *device, unsigned char *bytes, int count);
101 int snd_i2c_readbytes(struct snd_i2c_device *device, unsigned char *bytes, int count);
102 int snd_i2c_probeaddr(struct snd_i2c_bus *bus, unsigned short addr);
103 
104 #endif /* __SOUND_I2C_H */
105