xref: /openbmc/linux/include/sound/i2c.h (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
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 typedef struct _snd_i2c_device snd_i2c_device_t;
25 typedef struct _snd_i2c_bus snd_i2c_bus_t;
26 
27 #define SND_I2C_DEVICE_ADDRTEN	(1<<0)	/* 10-bit I2C address */
28 
29 struct _snd_i2c_device {
30 	struct list_head list;
31 	snd_i2c_bus_t *bus;	/* I2C bus */
32 	char name[32];		/* some useful device name */
33 	unsigned short flags;	/* device flags */
34 	unsigned short addr;	/* device address (might be 10-bit) */
35 	unsigned long private_value;
36 	void *private_data;
37 	void (*private_free)(snd_i2c_device_t *device);
38 };
39 
40 #define snd_i2c_device(n) list_entry(n, snd_i2c_device_t, list)
41 
42 typedef struct _snd_i2c_bit_ops {
43 	void (*start)(snd_i2c_bus_t *bus);	/* transfer start */
44 	void (*stop)(snd_i2c_bus_t *bus);	/* transfer stop */
45 	void (*direction)(snd_i2c_bus_t *bus, int clock, int data);  /* set line direction (0 = write, 1 = read) */
46 	void (*setlines)(snd_i2c_bus_t *bus, int clock, int data);
47 	int (*getclock)(snd_i2c_bus_t *bus);
48 	int (*getdata)(snd_i2c_bus_t *bus, int ack);
49 } snd_i2c_bit_ops_t;
50 
51 typedef struct _snd_i2c_ops {
52 	int (*sendbytes)(snd_i2c_device_t *device, unsigned char *bytes, int count);
53 	int (*readbytes)(snd_i2c_device_t *device, unsigned char *bytes, int count);
54 	int (*probeaddr)(snd_i2c_bus_t *bus, unsigned short addr);
55 } snd_i2c_ops_t;
56 
57 struct _snd_i2c_bus {
58 	snd_card_t *card;	/* card which I2C belongs to */
59 	char name[32];		/* some useful label */
60 
61 	struct semaphore lock_mutex;
62 
63 	snd_i2c_bus_t *master;	/* master bus when SCK/SCL is shared */
64 	struct list_head buses;	/* master: slave buses sharing SCK/SCL, slave: link list */
65 
66 	struct list_head devices; /* attached devices to this bus */
67 
68 	union {
69 		snd_i2c_bit_ops_t *bit;
70 		void *ops;
71 	} hw_ops;		/* lowlevel operations */
72 	snd_i2c_ops_t *ops;	/* midlevel operations */
73 
74 	unsigned long private_value;
75 	void *private_data;
76 	void (*private_free)(snd_i2c_bus_t *bus);
77 };
78 
79 #define snd_i2c_slave_bus(n) list_entry(n, snd_i2c_bus_t, buses)
80 
81 int snd_i2c_bus_create(snd_card_t *card, const char *name, snd_i2c_bus_t *master, snd_i2c_bus_t **ri2c);
82 int snd_i2c_device_create(snd_i2c_bus_t *bus, const char *name, unsigned char addr, snd_i2c_device_t **rdevice);
83 int snd_i2c_device_free(snd_i2c_device_t *device);
84 
85 static inline void snd_i2c_lock(snd_i2c_bus_t *bus) {
86 	if (bus->master)
87 		down(&bus->master->lock_mutex);
88 	else
89 		down(&bus->lock_mutex);
90 }
91 static inline void snd_i2c_unlock(snd_i2c_bus_t *bus) {
92 	if (bus->master)
93 		up(&bus->master->lock_mutex);
94 	else
95 		up(&bus->lock_mutex);
96 }
97 
98 int snd_i2c_sendbytes(snd_i2c_device_t *device, unsigned char *bytes, int count);
99 int snd_i2c_readbytes(snd_i2c_device_t *device, unsigned char *bytes, int count);
100 int snd_i2c_probeaddr(snd_i2c_bus_t *bus, unsigned short addr);
101 
102 #endif /* __SOUND_I2C_H */
103