[net-next-2.6.git] / sound / i2c / i2c.c

/*
 *   Generic i2c interface for ALSA
 *
 *   (c) 1998 Gerd Knorr <kraxel@cs.tu-berlin.de>
 *   Modified for the ALSA driver by Jaroslav Kysela <perex@perex.cz>
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#include <linux/init.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <sound/core.h>
#include <sound/i2c.h>

MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
MODULE_DESCRIPTION("Generic i2c interface for ALSA");
MODULE_LICENSE("GPL");

static int snd_i2c_bit_sendbytes(struct snd_i2c_device *device,
				 unsigned char *bytes, int count);
static int snd_i2c_bit_readbytes(struct snd_i2c_device *device,
				 unsigned char *bytes, int count);
static int snd_i2c_bit_probeaddr(struct snd_i2c_bus *bus,
				 unsigned short addr);

static struct snd_i2c_ops snd_i2c_bit_ops = {
	.sendbytes = snd_i2c_bit_sendbytes,
	.readbytes = snd_i2c_bit_readbytes,
	.probeaddr = snd_i2c_bit_probeaddr,
};

static int snd_i2c_bus_free(struct snd_i2c_bus *bus)
{
	struct snd_i2c_bus *slave;
	struct snd_i2c_device *device;

	if (snd_BUG_ON(!bus))
		return -EINVAL;
	while (!list_empty(&bus->devices)) {
		device = snd_i2c_device(bus->devices.next);
		snd_i2c_device_free(device);
	}
	if (bus->master)
		list_del(&bus->buses);
	else {
		while (!list_empty(&bus->buses)) {
			slave = snd_i2c_slave_bus(bus->buses.next);
			snd_device_free(bus->card, slave);
		}
	}
	if (bus->private_free)
		bus->private_free(bus);
	kfree(bus);
	return 0;
}

static int snd_i2c_bus_dev_free(struct snd_device *device)
{
	struct snd_i2c_bus *bus = device->device_data;
	return snd_i2c_bus_free(bus);
}

int snd_i2c_bus_create(struct snd_card *card, const char *name,
		       struct snd_i2c_bus *master, struct snd_i2c_bus **ri2c)
{
	struct snd_i2c_bus *bus;
	int err;
	static struct snd_device_ops ops = {
		.dev_free =	snd_i2c_bus_dev_free,
	};

	*ri2c = NULL;
	bus = kzalloc(sizeof(*bus), GFP_KERNEL);
	if (bus == NULL)
		return -ENOMEM;
	mutex_init(&bus->lock_mutex);
	INIT_LIST_HEAD(&bus->devices);
	INIT_LIST_HEAD(&bus->buses);
	bus->card = card;
	bus->ops = &snd_i2c_bit_ops;
	if (master) {
		list_add_tail(&bus->buses, &master->buses);
		bus->master = master;
	}
	strlcpy(bus->name, name, sizeof(bus->name));
	err = snd_device_new(card, SNDRV_DEV_BUS, bus, &ops);
	if (err < 0) {
		snd_i2c_bus_free(bus);
		return err;
	}
	*ri2c = bus;
	return 0;
}

EXPORT_SYMBOL(snd_i2c_bus_create);

int snd_i2c_device_create(struct snd_i2c_bus *bus, const char *name,
			  unsigned char addr, struct snd_i2c_device **rdevice)
{
	struct snd_i2c_device *device;

	*rdevice = NULL;
	if (snd_BUG_ON(!bus))
		return -EINVAL;
	device = kzalloc(sizeof(*device), GFP_KERNEL);
	if (device == NULL)
		return -ENOMEM;
	device->addr = addr;
	strlcpy(device->name, name, sizeof(device->name));
	list_add_tail(&device->list, &bus->devices);
	device->bus = bus;
	*rdevice = device;
	return 0;
}

EXPORT_SYMBOL(snd_i2c_device_create);

int snd_i2c_device_free(struct snd_i2c_device *device)
{
	if (device->bus)
		list_del(&device->list);
	if (device->private_free)
		device->private_free(device);
	kfree(device);
	return 0;
}

EXPORT_SYMBOL(snd_i2c_device_free);

int snd_i2c_sendbytes(struct snd_i2c_device *device, unsigned char *bytes, int count)
{
	return device->bus->ops->sendbytes(device, bytes, count);
}

EXPORT_SYMBOL(snd_i2c_sendbytes);

int snd_i2c_readbytes(struct snd_i2c_device *device, unsigned char *bytes, int count)
{
	return device->bus->ops->readbytes(device, bytes, count);
}

EXPORT_SYMBOL(snd_i2c_readbytes);

int snd_i2c_probeaddr(struct snd_i2c_bus *bus, unsigned short addr)
{
	return bus->ops->probeaddr(bus, addr);
}

EXPORT_SYMBOL(snd_i2c_probeaddr);

/*
 *  bit-operations
 */

static inline void snd_i2c_bit_hw_start(struct snd_i2c_bus *bus)
{
	if (bus->hw_ops.bit->start)
		bus->hw_ops.bit->start(bus);
}

static inline void snd_i2c_bit_hw_stop(struct snd_i2c_bus *bus)
{
	if (bus->hw_ops.bit->stop)
		bus->hw_ops.bit->stop(bus);
}

static void snd_i2c_bit_direction(struct snd_i2c_bus *bus, int clock, int data)
{
	if (bus->hw_ops.bit->direction)
		bus->hw_ops.bit->direction(bus, clock, data);
}

static void snd_i2c_bit_set(struct snd_i2c_bus *bus, int clock, int data)
{
	bus->hw_ops.bit->setlines(bus, clock, data);
}

#if 0
static int snd_i2c_bit_clock(struct snd_i2c_bus *bus)
{
	if (bus->hw_ops.bit->getclock)
		return bus->hw_ops.bit->getclock(bus);
	return -ENXIO;
}
#endif

static int snd_i2c_bit_data(struct snd_i2c_bus *bus, int ack)
{
	return bus->hw_ops.bit->getdata(bus, ack);
}

static void snd_i2c_bit_start(struct snd_i2c_bus *bus)
{
	snd_i2c_bit_hw_start(bus);
	snd_i2c_bit_direction(bus, 1, 1);	/* SCL - wr, SDA - wr */
	snd_i2c_bit_set(bus, 1, 1);
	snd_i2c_bit_set(bus, 1, 0);
	snd_i2c_bit_set(bus, 0, 0);
}

static void snd_i2c_bit_stop(struct snd_i2c_bus *bus)
{
	snd_i2c_bit_set(bus, 0, 0);
	snd_i2c_bit_set(bus, 1, 0);
	snd_i2c_bit_set(bus, 1, 1);
	snd_i2c_bit_hw_stop(bus);
}

static void snd_i2c_bit_send(struct snd_i2c_bus *bus, int data)
{
	snd_i2c_bit_set(bus, 0, data);
	snd_i2c_bit_set(bus, 1, data);
	snd_i2c_bit_set(bus, 0, data);
}

static int snd_i2c_bit_ack(struct snd_i2c_bus *bus)
{
	int ack;

	snd_i2c_bit_set(bus, 0, 1);
	snd_i2c_bit_set(bus, 1, 1);
	snd_i2c_bit_direction(bus, 1, 0);	/* SCL - wr, SDA - rd */
	ack = snd_i2c_bit_data(bus, 1);
	snd_i2c_bit_direction(bus, 1, 1);	/* SCL - wr, SDA - wr */
	snd_i2c_bit_set(bus, 0, 1);
	return ack ? -EIO : 0;
}

static int snd_i2c_bit_sendbyte(struct snd_i2c_bus *bus, unsigned char data)
{
	int i, err;

	for (i = 7; i >= 0; i--)
		snd_i2c_bit_send(bus, !!(data & (1 << i)));
	err = snd_i2c_bit_ack(bus);
	if (err < 0)
		return err;
	return 0;
}

static int snd_i2c_bit_readbyte(struct snd_i2c_bus *bus, int last)
{
	int i;
	unsigned char data = 0;

	snd_i2c_bit_set(bus, 0, 1);
	snd_i2c_bit_direction(bus, 1, 0);	/* SCL - wr, SDA - rd */
	for (i = 7; i >= 0; i--) {
		snd_i2c_bit_set(bus, 1, 1);
		if (snd_i2c_bit_data(bus, 0))
			data |= (1 << i);
		snd_i2c_bit_set(bus, 0, 1);
	}
	snd_i2c_bit_direction(bus, 1, 1);	/* SCL - wr, SDA - wr */
	snd_i2c_bit_send(bus, !!last);
	return data;
}

static int snd_i2c_bit_sendbytes(struct snd_i2c_device *device,
				 unsigned char *bytes, int count)
{
	struct snd_i2c_bus *bus = device->bus;
	int err, res = 0;

	if (device->flags & SND_I2C_DEVICE_ADDRTEN)
		return -EIO;		/* not yet implemented */
	snd_i2c_bit_start(bus);
	err = snd_i2c_bit_sendbyte(bus, device->addr << 1);
	if (err < 0) {
		snd_i2c_bit_hw_stop(bus);
		return err;
	}
	while (count-- > 0) {
		err = snd_i2c_bit_sendbyte(bus, *bytes++);
		if (err < 0) {
			snd_i2c_bit_hw_stop(bus);
			return err;
		}
		res++;
	}
	snd_i2c_bit_stop(bus);
	return res;
}

static int snd_i2c_bit_readbytes(struct snd_i2c_device *device,
				 unsigned char *bytes, int count)
{
	struct snd_i2c_bus *bus = device->bus;
	int err, res = 0;

	if (device->flags & SND_I2C_DEVICE_ADDRTEN)
		return -EIO;		/* not yet implemented */
	snd_i2c_bit_start(bus);
	err = snd_i2c_bit_sendbyte(bus, (device->addr << 1) | 1);
	if (err < 0) {
		snd_i2c_bit_hw_stop(bus);
		return err;
	}
	while (count-- > 0) {
		err = snd_i2c_bit_readbyte(bus, count == 0);
		if (err < 0) {
			snd_i2c_bit_hw_stop(bus);
			return err;
		}
		*bytes++ = (unsigned char)err;
		res++;
	}
	snd_i2c_bit_stop(bus);
	return res;
}

static int snd_i2c_bit_probeaddr(struct snd_i2c_bus *bus, unsigned short addr)
{
	int err;

	if (addr & 0x8000)	/* 10-bit address */
		return -EIO;	/* not yet implemented */
	if (addr & 0x7f80)	/* invalid address */
		return -EINVAL;
	snd_i2c_bit_start(bus);
	err = snd_i2c_bit_sendbyte(bus, addr << 1);
	snd_i2c_bit_stop(bus);
	return err;
}


static int __init alsa_i2c_init(void)
{
	return 0;
}

static void __exit alsa_i2c_exit(void)
{
}

module_init(alsa_i2c_init)
module_exit(alsa_i2c_exit)
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Generic i2c interface for ALSA
	3	*
	4	* (c) 1998 Gerd Knorr <kraxel@cs.tu-berlin.de>
c1017a4c	5	* Modified for the ALSA driver by Jaroslav Kysela <perex@perex.cz>
1da177e4 LT	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
1da177e4 LT	23	#include <linux/init.h>
	24	#include <linux/slab.h>
	25	#include <linux/string.h>
	26	#include <linux/errno.h>
	27	#include <sound/core.h>
	28	#include <sound/i2c.h>
	29
c1017a4c	30	MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
1da177e4 LT	31	MODULE_DESCRIPTION("Generic i2c interface for ALSA");
	32	MODULE_LICENSE("GPL");
	33
97f02e05 TI	34	static int snd_i2c_bit_sendbytes(struct snd_i2c_device *device,
	35	unsigned char *bytes, int count);
	36	static int snd_i2c_bit_readbytes(struct snd_i2c_device *device,
	37	unsigned char *bytes, int count);
	38	static int snd_i2c_bit_probeaddr(struct snd_i2c_bus *bus,
	39	unsigned short addr);
	40
	41	static struct snd_i2c_ops snd_i2c_bit_ops = {
1da177e4 LT	42	.sendbytes = snd_i2c_bit_sendbytes,
	43	.readbytes = snd_i2c_bit_readbytes,
	44	.probeaddr = snd_i2c_bit_probeaddr,
	45	};
	46
97f02e05	47	static int snd_i2c_bus_free(struct snd_i2c_bus *bus)
1da177e4	48	{
97f02e05 TI	49	struct snd_i2c_bus *slave;
97f02e05 TI	50	struct snd_i2c_device *device;
1da177e4	51
5e246b85 TI	52	if (snd_BUG_ON(!bus))
5e246b85 TI	53	return -EINVAL;
1da177e4 LT	54	while (!list_empty(&bus->devices)) {
	55	device = snd_i2c_device(bus->devices.next);
	56	snd_i2c_device_free(device);
	57	}
	58	if (bus->master)
	59	list_del(&bus->buses);
	60	else {
	61	while (!list_empty(&bus->buses)) {
	62	slave = snd_i2c_slave_bus(bus->buses.next);
	63	snd_device_free(bus->card, slave);
	64	}
	65	}
	66	if (bus->private_free)
	67	bus->private_free(bus);
	68	kfree(bus);
	69	return 0;
	70	}
	71
97f02e05	72	static int snd_i2c_bus_dev_free(struct snd_device *device)
1da177e4	73	{
97f02e05	74	struct snd_i2c_bus *bus = device->device_data;
1da177e4 LT	75	return snd_i2c_bus_free(bus);
	76	}
	77
97f02e05 TI	78	int snd_i2c_bus_create(struct snd_card card, const char name,
97f02e05 TI	79	struct snd_i2c_bus master, struct snd_i2c_bus *ri2c)
1da177e4	80	{
97f02e05	81	struct snd_i2c_bus *bus;
1da177e4	82	int err;
97f02e05	83	static struct snd_device_ops ops = {
1da177e4 LT	84	.dev_free = snd_i2c_bus_dev_free,
	85	};
	86
	87	*ri2c = NULL;
561b220a	88	bus = kzalloc(sizeof(*bus), GFP_KERNEL);
1da177e4 LT	89	if (bus == NULL)
1da177e4 LT	90	return -ENOMEM;
ef9f0a42	91	mutex_init(&bus->lock_mutex);
1da177e4 LT	92	INIT_LIST_HEAD(&bus->devices);
	93	INIT_LIST_HEAD(&bus->buses);
	94	bus->card = card;
	95	bus->ops = &snd_i2c_bit_ops;
	96	if (master) {
	97	list_add_tail(&bus->buses, &master->buses);
	98	bus->master = master;
	99	}
	100	strlcpy(bus->name, name, sizeof(bus->name));
1cff399e BW	101	err = snd_device_new(card, SNDRV_DEV_BUS, bus, &ops);
1cff399e BW	102	if (err < 0) {
1da177e4 LT	103	snd_i2c_bus_free(bus);
	104	return err;
	105	}
	106	*ri2c = bus;
	107	return 0;
	108	}
	109
57c65c11 TI	110	EXPORT_SYMBOL(snd_i2c_bus_create);
57c65c11 TI	111
97f02e05 TI	112	int snd_i2c_device_create(struct snd_i2c_bus bus, const char name,
97f02e05 TI	113	unsigned char addr, struct snd_i2c_device **rdevice)
1da177e4	114	{
97f02e05	115	struct snd_i2c_device *device;
1da177e4 LT	116
1da177e4 LT	117	*rdevice = NULL;
5e246b85 TI	118	if (snd_BUG_ON(!bus))
5e246b85 TI	119	return -EINVAL;
561b220a	120	device = kzalloc(sizeof(*device), GFP_KERNEL);
1da177e4 LT	121	if (device == NULL)
	122	return -ENOMEM;
	123	device->addr = addr;
	124	strlcpy(device->name, name, sizeof(device->name));
	125	list_add_tail(&device->list, &bus->devices);
	126	device->bus = bus;
	127	*rdevice = device;
	128	return 0;
	129	}
	130
57c65c11 TI	131	EXPORT_SYMBOL(snd_i2c_device_create);
57c65c11 TI	132
97f02e05	133	int snd_i2c_device_free(struct snd_i2c_device *device)
1da177e4 LT	134	{
	135	if (device->bus)
	136	list_del(&device->list);
	137	if (device->private_free)
	138	device->private_free(device);
	139	kfree(device);
	140	return 0;
	141	}
	142
57c65c11 TI	143	EXPORT_SYMBOL(snd_i2c_device_free);
57c65c11 TI	144
97f02e05	145	int snd_i2c_sendbytes(struct snd_i2c_device device, unsigned char bytes, int count)
1da177e4 LT	146	{
	147	return device->bus->ops->sendbytes(device, bytes, count);
	148	}
	149
57c65c11	150	EXPORT_SYMBOL(snd_i2c_sendbytes);
1da177e4	151
97f02e05	152	int snd_i2c_readbytes(struct snd_i2c_device device, unsigned char bytes, int count)
1da177e4 LT	153	{
	154	return device->bus->ops->readbytes(device, bytes, count);
	155	}
	156
57c65c11 TI	157	EXPORT_SYMBOL(snd_i2c_readbytes);
57c65c11 TI	158
97f02e05	159	int snd_i2c_probeaddr(struct snd_i2c_bus *bus, unsigned short addr)
1da177e4 LT	160	{
	161	return bus->ops->probeaddr(bus, addr);
	162	}
	163
57c65c11 TI	164	EXPORT_SYMBOL(snd_i2c_probeaddr);
57c65c11 TI	165
1da177e4 LT	166	/*
	167	* bit-operations
	168	*/
	169
97f02e05	170	static inline void snd_i2c_bit_hw_start(struct snd_i2c_bus *bus)
1da177e4 LT	171	{
	172	if (bus->hw_ops.bit->start)
	173	bus->hw_ops.bit->start(bus);
	174	}
	175
97f02e05	176	static inline void snd_i2c_bit_hw_stop(struct snd_i2c_bus *bus)
1da177e4 LT	177	{
	178	if (bus->hw_ops.bit->stop)
	179	bus->hw_ops.bit->stop(bus);
	180	}
	181
97f02e05	182	static void snd_i2c_bit_direction(struct snd_i2c_bus *bus, int clock, int data)
1da177e4 LT	183	{
	184	if (bus->hw_ops.bit->direction)
	185	bus->hw_ops.bit->direction(bus, clock, data);
	186	}
	187
97f02e05	188	static void snd_i2c_bit_set(struct snd_i2c_bus *bus, int clock, int data)
1da177e4 LT	189	{
	190	bus->hw_ops.bit->setlines(bus, clock, data);
	191	}
	192
	193	#if 0
97f02e05	194	static int snd_i2c_bit_clock(struct snd_i2c_bus *bus)
1da177e4 LT	195	{
	196	if (bus->hw_ops.bit->getclock)
	197	return bus->hw_ops.bit->getclock(bus);
	198	return -ENXIO;
	199	}
	200	#endif
	201
97f02e05	202	static int snd_i2c_bit_data(struct snd_i2c_bus *bus, int ack)
1da177e4 LT	203	{
	204	return bus->hw_ops.bit->getdata(bus, ack);
	205	}
	206
97f02e05	207	static void snd_i2c_bit_start(struct snd_i2c_bus *bus)
1da177e4 LT	208	{
	209	snd_i2c_bit_hw_start(bus);
	210	snd_i2c_bit_direction(bus, 1, 1); /* SCL - wr, SDA - wr */
	211	snd_i2c_bit_set(bus, 1, 1);
	212	snd_i2c_bit_set(bus, 1, 0);
	213	snd_i2c_bit_set(bus, 0, 0);
	214	}
	215
97f02e05	216	static void snd_i2c_bit_stop(struct snd_i2c_bus *bus)
1da177e4 LT	217	{
	218	snd_i2c_bit_set(bus, 0, 0);
	219	snd_i2c_bit_set(bus, 1, 0);
	220	snd_i2c_bit_set(bus, 1, 1);
	221	snd_i2c_bit_hw_stop(bus);
	222	}
	223
97f02e05	224	static void snd_i2c_bit_send(struct snd_i2c_bus *bus, int data)
1da177e4 LT	225	{
	226	snd_i2c_bit_set(bus, 0, data);
	227	snd_i2c_bit_set(bus, 1, data);
	228	snd_i2c_bit_set(bus, 0, data);
	229	}
	230
97f02e05	231	static int snd_i2c_bit_ack(struct snd_i2c_bus *bus)
1da177e4 LT	232	{
	233	int ack;
	234
	235	snd_i2c_bit_set(bus, 0, 1);
	236	snd_i2c_bit_set(bus, 1, 1);
	237	snd_i2c_bit_direction(bus, 1, 0); /* SCL - wr, SDA - rd */
	238	ack = snd_i2c_bit_data(bus, 1);
	239	snd_i2c_bit_direction(bus, 1, 1); /* SCL - wr, SDA - wr */
	240	snd_i2c_bit_set(bus, 0, 1);
	241	return ack ? -EIO : 0;
	242	}
	243
97f02e05	244	static int snd_i2c_bit_sendbyte(struct snd_i2c_bus *bus, unsigned char data)
1da177e4 LT	245	{
	246	int i, err;
	247
	248	for (i = 7; i >= 0; i--)
	249	snd_i2c_bit_send(bus, !!(data & (1 << i)));
1cff399e BW	250	err = snd_i2c_bit_ack(bus);
1cff399e BW	251	if (err < 0)
1da177e4 LT	252	return err;
	253	return 0;
	254	}
	255
97f02e05	256	static int snd_i2c_bit_readbyte(struct snd_i2c_bus *bus, int last)
1da177e4 LT	257	{
	258	int i;
	259	unsigned char data = 0;
	260
	261	snd_i2c_bit_set(bus, 0, 1);
	262	snd_i2c_bit_direction(bus, 1, 0); /* SCL - wr, SDA - rd */
	263	for (i = 7; i >= 0; i--) {
	264	snd_i2c_bit_set(bus, 1, 1);
	265	if (snd_i2c_bit_data(bus, 0))
	266	data \|= (1 << i);
	267	snd_i2c_bit_set(bus, 0, 1);
	268	}
	269	snd_i2c_bit_direction(bus, 1, 1); /* SCL - wr, SDA - wr */
	270	snd_i2c_bit_send(bus, !!last);
	271	return data;
	272	}
	273
97f02e05 TI	274	static int snd_i2c_bit_sendbytes(struct snd_i2c_device *device,
97f02e05 TI	275	unsigned char *bytes, int count)
1da177e4	276	{
97f02e05	277	struct snd_i2c_bus *bus = device->bus;
1da177e4 LT	278	int err, res = 0;
	279
	280	if (device->flags & SND_I2C_DEVICE_ADDRTEN)
	281	return -EIO; /* not yet implemented */
	282	snd_i2c_bit_start(bus);
1cff399e BW	283	err = snd_i2c_bit_sendbyte(bus, device->addr << 1);
1cff399e BW	284	if (err < 0) {
1da177e4 LT	285	snd_i2c_bit_hw_stop(bus);
	286	return err;
	287	}
	288	while (count-- > 0) {
1cff399e BW	289	err = snd_i2c_bit_sendbyte(bus, *bytes++);
1cff399e BW	290	if (err < 0) {
1da177e4 LT	291	snd_i2c_bit_hw_stop(bus);
	292	return err;
	293	}
	294	res++;
	295	}
	296	snd_i2c_bit_stop(bus);
	297	return res;
	298	}
	299
97f02e05 TI	300	static int snd_i2c_bit_readbytes(struct snd_i2c_device *device,
97f02e05 TI	301	unsigned char *bytes, int count)
1da177e4	302	{
97f02e05	303	struct snd_i2c_bus *bus = device->bus;
1da177e4 LT	304	int err, res = 0;
	305
	306	if (device->flags & SND_I2C_DEVICE_ADDRTEN)
	307	return -EIO; /* not yet implemented */
	308	snd_i2c_bit_start(bus);
1cff399e BW	309	err = snd_i2c_bit_sendbyte(bus, (device->addr << 1) \| 1);
1cff399e BW	310	if (err < 0) {
1da177e4 LT	311	snd_i2c_bit_hw_stop(bus);
	312	return err;
	313	}
	314	while (count-- > 0) {
1cff399e BW	315	err = snd_i2c_bit_readbyte(bus, count == 0);
1cff399e BW	316	if (err < 0) {
1da177e4 LT	317	snd_i2c_bit_hw_stop(bus);
	318	return err;
	319	}
	320	*bytes++ = (unsigned char)err;
	321	res++;
	322	}
	323	snd_i2c_bit_stop(bus);
	324	return res;
	325	}
	326
97f02e05	327	static int snd_i2c_bit_probeaddr(struct snd_i2c_bus *bus, unsigned short addr)
1da177e4 LT	328	{
	329	int err;
	330
	331	if (addr & 0x8000) /* 10-bit address */
	332	return -EIO; /* not yet implemented */
	333	if (addr & 0x7f80) /* invalid address */
	334	return -EINVAL;
	335	snd_i2c_bit_start(bus);
	336	err = snd_i2c_bit_sendbyte(bus, addr << 1);
	337	snd_i2c_bit_stop(bus);
	338	return err;
	339	}
	340
1da177e4 LT	341
	342	static int __init alsa_i2c_init(void)
	343	{
	344	return 0;
	345	}
	346
	347	static void __exit alsa_i2c_exit(void)
	348	{
	349	}
	350
	351	module_init(alsa_i2c_init)
	352	module_exit(alsa_i2c_exit)