linux/sound/i2c/i2c.c
Takashi Iwai 561b220a4d [ALSA] Replace with kzalloc() - others
Documentation,SA11xx UDA1341 driver,Generic drivers,MPU401 UART,OPL3
OPL4,Digigram VX core,I2C cs8427,I2C lib core,I2C tea6330t,L3 drivers
AK4114 receiver,AK4117 receiver,PDAudioCF driver,PPC PMAC driver
SPARC AMD7930 driver,SPARC cs4231 driver,Synth,Common EMU synth
USB generic driver,USB USX2Y
Replace kcalloc(1,..) with kzalloc().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2005-09-12 10:48:22 +02:00

334 lines
8.1 KiB
C

/*
* Generic i2c interface for ALSA
*
* (c) 1998 Gerd Knorr <kraxel@cs.tu-berlin.de>
* Modified for the ALSA driver by Jaroslav Kysela <perex@suse.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 <sound/driver.h>
#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@suse.cz>");
MODULE_DESCRIPTION("Generic i2c interface for ALSA");
MODULE_LICENSE("GPL");
static int snd_i2c_bit_sendbytes(snd_i2c_device_t *device, unsigned char *bytes, int count);
static int snd_i2c_bit_readbytes(snd_i2c_device_t *device, unsigned char *bytes, int count);
static int snd_i2c_bit_probeaddr(snd_i2c_bus_t *bus, unsigned short addr);
static snd_i2c_ops_t 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(snd_i2c_bus_t *bus)
{
snd_i2c_bus_t *slave;
snd_i2c_device_t *device;
snd_assert(bus != NULL, 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(snd_device_t *device)
{
snd_i2c_bus_t *bus = device->device_data;
return snd_i2c_bus_free(bus);
}
int snd_i2c_bus_create(snd_card_t *card, const char *name, snd_i2c_bus_t *master, snd_i2c_bus_t **ri2c)
{
snd_i2c_bus_t *bus;
int err;
static snd_device_ops_t ops = {
.dev_free = snd_i2c_bus_dev_free,
};
*ri2c = NULL;
bus = kzalloc(sizeof(*bus), GFP_KERNEL);
if (bus == NULL)
return -ENOMEM;
init_MUTEX(&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));
if ((err = snd_device_new(card, SNDRV_DEV_BUS, bus, &ops)) < 0) {
snd_i2c_bus_free(bus);
return err;
}
*ri2c = bus;
return 0;
}
int snd_i2c_device_create(snd_i2c_bus_t *bus, const char *name, unsigned char addr, snd_i2c_device_t **rdevice)
{
snd_i2c_device_t *device;
*rdevice = NULL;
snd_assert(bus != NULL, 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;
}
int snd_i2c_device_free(snd_i2c_device_t *device)
{
if (device->bus)
list_del(&device->list);
if (device->private_free)
device->private_free(device);
kfree(device);
return 0;
}
int snd_i2c_sendbytes(snd_i2c_device_t *device, unsigned char *bytes, int count)
{
return device->bus->ops->sendbytes(device, bytes, count);
}
int snd_i2c_readbytes(snd_i2c_device_t *device, unsigned char *bytes, int count)
{
return device->bus->ops->readbytes(device, bytes, count);
}
int snd_i2c_probeaddr(snd_i2c_bus_t *bus, unsigned short addr)
{
return bus->ops->probeaddr(bus, addr);
}
/*
* bit-operations
*/
static inline void snd_i2c_bit_hw_start(snd_i2c_bus_t *bus)
{
if (bus->hw_ops.bit->start)
bus->hw_ops.bit->start(bus);
}
static inline void snd_i2c_bit_hw_stop(snd_i2c_bus_t *bus)
{
if (bus->hw_ops.bit->stop)
bus->hw_ops.bit->stop(bus);
}
static void snd_i2c_bit_direction(snd_i2c_bus_t *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(snd_i2c_bus_t *bus, int clock, int data)
{
bus->hw_ops.bit->setlines(bus, clock, data);
}
#if 0
static int snd_i2c_bit_clock(snd_i2c_bus_t *bus)
{
if (bus->hw_ops.bit->getclock)
return bus->hw_ops.bit->getclock(bus);
return -ENXIO;
}
#endif
static int snd_i2c_bit_data(snd_i2c_bus_t *bus, int ack)
{
return bus->hw_ops.bit->getdata(bus, ack);
}
static void snd_i2c_bit_start(snd_i2c_bus_t *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(snd_i2c_bus_t *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(snd_i2c_bus_t *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(snd_i2c_bus_t *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(snd_i2c_bus_t *bus, unsigned char data)
{
int i, err;
for (i = 7; i >= 0; i--)
snd_i2c_bit_send(bus, !!(data & (1 << i)));
if ((err = snd_i2c_bit_ack(bus)) < 0)
return err;
return 0;
}
static int snd_i2c_bit_readbyte(snd_i2c_bus_t *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(snd_i2c_device_t *device, unsigned char *bytes, int count)
{
snd_i2c_bus_t *bus = device->bus;
int err, res = 0;
if (device->flags & SND_I2C_DEVICE_ADDRTEN)
return -EIO; /* not yet implemented */
snd_i2c_bit_start(bus);
if ((err = snd_i2c_bit_sendbyte(bus, device->addr << 1)) < 0) {
snd_i2c_bit_hw_stop(bus);
return err;
}
while (count-- > 0) {
if ((err = snd_i2c_bit_sendbyte(bus, *bytes++)) < 0) {
snd_i2c_bit_hw_stop(bus);
return err;
}
res++;
}
snd_i2c_bit_stop(bus);
return res;
}
static int snd_i2c_bit_readbytes(snd_i2c_device_t *device, unsigned char *bytes, int count)
{
snd_i2c_bus_t *bus = device->bus;
int err, res = 0;
if (device->flags & SND_I2C_DEVICE_ADDRTEN)
return -EIO; /* not yet implemented */
snd_i2c_bit_start(bus);
if ((err = snd_i2c_bit_sendbyte(bus, (device->addr << 1) | 1)) < 0) {
snd_i2c_bit_hw_stop(bus);
return err;
}
while (count-- > 0) {
if ((err = snd_i2c_bit_readbyte(bus, count == 0)) < 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(snd_i2c_bus_t *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;
}
EXPORT_SYMBOL(snd_i2c_bus_create);
EXPORT_SYMBOL(snd_i2c_device_create);
EXPORT_SYMBOL(snd_i2c_device_free);
EXPORT_SYMBOL(snd_i2c_sendbytes);
EXPORT_SYMBOL(snd_i2c_readbytes);
EXPORT_SYMBOL(snd_i2c_probeaddr);
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)