Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / sound / i2c / i2c.c
diff --git a/kernel/sound/i2c/i2c.c b/kernel/sound/i2c/i2c.c
new file mode 100644 (file)
index 0000000..4677037
--- /dev/null
@@ -0,0 +1,353 @@
+/*
+ *   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/module.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)