xref: /openbmc/linux/include/sound/i2c.h (revision 75bf465f0bc33e9b776a46d6a1b9b990f5fb7c37)
1  /* SPDX-License-Identifier: GPL-2.0-or-later */
2  #ifndef __SOUND_I2C_H
3  #define __SOUND_I2C_H
4  
5  /*
6   */
7  
8  #define SND_I2C_DEVICE_ADDRTEN	(1<<0)	/* 10-bit I2C address */
9  
10  struct snd_i2c_device {
11  	struct list_head list;
12  	struct snd_i2c_bus *bus;	/* I2C bus */
13  	char name[32];		/* some useful device name */
14  	unsigned short flags;	/* device flags */
15  	unsigned short addr;	/* device address (might be 10-bit) */
16  	unsigned long private_value;
17  	void *private_data;
18  	void (*private_free)(struct snd_i2c_device *device);
19  };
20  
21  #define snd_i2c_device(n) list_entry(n, struct snd_i2c_device, list)
22  
23  struct snd_i2c_bit_ops {
24  	void (*start)(struct snd_i2c_bus *bus);	/* transfer start */
25  	void (*stop)(struct snd_i2c_bus *bus);	/* transfer stop */
26  	void (*direction)(struct snd_i2c_bus *bus, int clock, int data);  /* set line direction (0 = write, 1 = read) */
27  	void (*setlines)(struct snd_i2c_bus *bus, int clock, int data);
28  	int (*getclock)(struct snd_i2c_bus *bus);
29  	int (*getdata)(struct snd_i2c_bus *bus, int ack);
30  };
31  
32  struct snd_i2c_ops {
33  	int (*sendbytes)(struct snd_i2c_device *device, unsigned char *bytes, int count);
34  	int (*readbytes)(struct snd_i2c_device *device, unsigned char *bytes, int count);
35  	int (*probeaddr)(struct snd_i2c_bus *bus, unsigned short addr);
36  };
37  
38  struct snd_i2c_bus {
39  	struct snd_card *card;	/* card which I2C belongs to */
40  	char name[32];		/* some useful label */
41  
42  	struct mutex lock_mutex;
43  
44  	struct snd_i2c_bus *master;	/* master bus when SCK/SCL is shared */
45  	struct list_head buses;	/* master: slave buses sharing SCK/SCL, slave: link list */
46  
47  	struct list_head devices; /* attached devices to this bus */
48  
49  	union {
50  		struct snd_i2c_bit_ops *bit;
51  		void *ops;
52  	} hw_ops;		/* lowlevel operations */
53  	const struct snd_i2c_ops *ops;	/* midlevel operations */
54  
55  	unsigned long private_value;
56  	void *private_data;
57  	void (*private_free)(struct snd_i2c_bus *bus);
58  };
59  
60  #define snd_i2c_slave_bus(n) list_entry(n, struct snd_i2c_bus, buses)
61  
62  int snd_i2c_bus_create(struct snd_card *card, const char *name,
63  		       struct snd_i2c_bus *master, struct snd_i2c_bus **ri2c);
64  int snd_i2c_device_create(struct snd_i2c_bus *bus, const char *name,
65  			  unsigned char addr, struct snd_i2c_device **rdevice);
66  int snd_i2c_device_free(struct snd_i2c_device *device);
67  
snd_i2c_lock(struct snd_i2c_bus * bus)68  static inline void snd_i2c_lock(struct snd_i2c_bus *bus)
69  {
70  	if (bus->master)
71  		mutex_lock(&bus->master->lock_mutex);
72  	else
73  		mutex_lock(&bus->lock_mutex);
74  }
75  
snd_i2c_unlock(struct snd_i2c_bus * bus)76  static inline void snd_i2c_unlock(struct snd_i2c_bus *bus)
77  {
78  	if (bus->master)
79  		mutex_unlock(&bus->master->lock_mutex);
80  	else
81  		mutex_unlock(&bus->lock_mutex);
82  }
83  
84  int snd_i2c_sendbytes(struct snd_i2c_device *device, unsigned char *bytes, int count);
85  int snd_i2c_readbytes(struct snd_i2c_device *device, unsigned char *bytes, int count);
86  int snd_i2c_probeaddr(struct snd_i2c_bus *bus, unsigned short addr);
87  
88  #endif /* __SOUND_I2C_H */
89