[ALSA] snd-aoa: add snd-aoa

This large patch adds all of snd-aoa.
Consisting of many modules, it currently replaces snd-powermac
for all layout-id based machines and handles many more (for
example new powerbooks and powermacs with digital output that
previously couldn't be used at all).
It also has support for all layout-IDs that Apple has (judging
from their Info.plist file) but not all are tested.
The driver currently has 2 known regressions over snd-powermac:
 * it doesn't handle powermac 7,2 and 7,3
 * it doesn't have a DRC control on snapper-based machines
I will fix those during the 2.6.18 development cycle.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 654 insertions, 0 deletions

diff --git a/sound/aoa/codecs/snd-aoa-codec-tas.c b/sound/aoa/codecs/snd-aoa-codec-tas.c
new file mode 100644
index 000000000000..2e39ff6ee349
--- /dev/null
+++ b/sound/aoa/codecs/snd-aoa-codec-tas.c
@@ -0,0 +1,654 @@
+/*
+ * Apple Onboard Audio driver for tas codec
+ *
+ * Copyright 2006 Johannes Berg <johannes@sipsolutions.net>
+ *
+ * GPL v2, can be found in COPYING.
+ *
+ * Open questions:
+ *  - How to distinguish between 3004 and versions?
+ *
+ * FIXMEs:
+ *  - This codec driver doesn't honour the 'connected'
+ *    property of the aoa_codec struct, hence if
+ *    it is used in machines where not everything is
+ *    connected it will display wrong mixer elements.
+ *  - Driver assumes that the microphone is always
+ *    monaureal and connected to the right channel of
+ *    the input. This should also be a codec-dependent
+ *    flag, maybe the codec should have 3 different
+ *    bits for the three different possibilities how
+ *    it can be hooked up...
+ *    But as long as I don't see any hardware hooked
+ *    up that way...
+ *  - As Apple notes in their code, the tas3004 seems
+ *    to delay the right channel by one sample. You can
+ *    see this when for example recording stereo in
+ *    audacity, or recording the tas output via cable
+ *    on another machine (use a sinus generator or so).
+ *    I tried programming the BiQuads but couldn't
+ *    make the delay work, maybe someone can read the
+ *    datasheet and fix it. The relevant Apple comment
+ *    is in AppleTAS3004Audio.cpp lines 1637 ff. Note
+ *    that their comment describing how they program
+ *    the filters sucks...
+ *
+ * Other things:
+ *  - this should actually register *two* aoa_codec
+ *    structs since it has two inputs. Then it must
+ *    use the prepare callback to forbid running the
+ *    secondary output on a different clock.
+ *    Also, whatever bus knows how to do this must
+ *    provide two soundbus_dev devices and the fabric
+ *    must be able to link them correctly.
+ *
+ *    I don't even know if Apple ever uses the second
+ *    port on the tas3004 though, I don't think their
+ *    i2s controllers can even do it. OTOH, they all
+ *    derive the clocks from common clocks, so it
+ *    might just be possible. The framework allows the
+ *    codec to refine the transfer_info items in the
+ *    usable callback, so we can simply remove the
+ *    rates the second instance is not using when it
+ *    actually is in use.
+ *    Maybe we'll need to make the sound busses have
+ *    a 'clock group id' value so the codec can
+ *    determine if the two outputs can be driven at
+ *    the same time. But that is likely overkill, up
+ *    to the fabric to not link them up incorrectly,
+ *    and up to the hardware designer to not wire
+ *    them up in some weird unusable way.
+ */
+#include <stddef.h>
+#include <linux/i2c.h>
+#include <linux/i2c-dev.h>
+#include <asm/pmac_low_i2c.h>
+#include <asm/prom.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("tas codec driver for snd-aoa");
+
+#include "snd-aoa-codec-tas.h"
+#include "snd-aoa-codec-tas-gain-table.h"
+#include "../aoa.h"
+#include "../soundbus/soundbus.h"
+
+
+#define PFX "snd-aoa-codec-tas: "
+
+struct tas {
+        struct aoa_codec        codec;
+        struct i2c_client       i2c;
+        u32                     muted_l:1, muted_r:1,
+                                controls_created:1;
+        u8                      cached_volume_l, cached_volume_r;
+        u8                      mixer_l[3], mixer_r[3];
+        u8                      acr;
+};
+
+static struct tas *codec_to_tas(struct aoa_codec *codec)
+{
+        return container_of(codec, struct tas, codec);
+}
+
+static inline int tas_write_reg(struct tas *tas, u8 reg, u8 len, u8 *data)
+{
+        if (len == 1)
+                return i2c_smbus_write_byte_data(&tas->i2c, reg, *data);
+        else
+                return i2c_smbus_write_i2c_block_data(&tas->i2c, reg, len, data);
+}
+
+static void tas_set_volume(struct tas *tas)
+{
+        u8 block[6];
+        int tmp;
+        u8 left, right;
+
+        left = tas->cached_volume_l;
+        right = tas->cached_volume_r;
+
+        if (left > 177) left = 177;
+        if (right > 177) right = 177;
+
+        if (tas->muted_l) left = 0;
+        if (tas->muted_r) right = 0;
+
+        /* analysing the volume and mixer tables shows
+         * that they are similar enough when we shift
+         * the mixer table down by 4 bits. The error
+         * is miniscule, in just one item the error
+         * is 1, at a value of 0x07f17b (mixer table
+         * value is 0x07f17a) */
+        tmp = tas_gaintable[left];
+        block[0] = tmp>>20;
+        block[1] = tmp>>12;
+        block[2] = tmp>>4;
+        tmp = tas_gaintable[right];
+        block[3] = tmp>>20;
+        block[4] = tmp>>12;
+        block[5] = tmp>>4;
+        tas_write_reg(tas, TAS_REG_VOL, 6, block);
+}
+
+static void tas_set_mixer(struct tas *tas)
+{
+        u8 block[9];
+        int tmp, i;
+        u8 val;
+
+        for (i=0;i<3;i++) {
+                val = tas->mixer_l[i];
+                if (val > 177) val = 177;
+                tmp = tas_gaintable[val];
+                block[3*i+0] = tmp>>16;
+                block[3*i+1] = tmp>>8;
+                block[3*i+2] = tmp;
+        }
+        tas_write_reg(tas, TAS_REG_LMIX, 9, block);
+
+        for (i=0;i<3;i++) {
+                val = tas->mixer_r[i];
+                if (val > 177) val = 177;
+                tmp = tas_gaintable[val];
+                block[3*i+0] = tmp>>16;
+                block[3*i+1] = tmp>>8;
+                block[3*i+2] = tmp;
+        }
+        tas_write_reg(tas, TAS_REG_RMIX, 9, block);
+}
+
+/* alsa stuff */
+
+static int tas_dev_register(struct snd_device *dev)
+{
+        return 0;
+}
+
+static struct snd_device_ops ops = {
+        .dev_register = tas_dev_register,
+};
+
+static int tas_snd_vol_info(struct snd_kcontrol *kcontrol,
+        struct snd_ctl_elem_info *uinfo)
+{
+        uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+        uinfo->count = 2;
+        uinfo->value.integer.min = 0;
+        uinfo->value.integer.max = 177;
+        return 0;
+}
+
+static int tas_snd_vol_get(struct snd_kcontrol *kcontrol,
+        struct snd_ctl_elem_value *ucontrol)
+{
+        struct tas *tas = snd_kcontrol_chip(kcontrol);
+
+        ucontrol->value.integer.value[0] = tas->cached_volume_l;
+        ucontrol->value.integer.value[1] = tas->cached_volume_r;
+        return 0;
+}
+
+static int tas_snd_vol_put(struct snd_kcontrol *kcontrol,
+        struct snd_ctl_elem_value *ucontrol)
+{
+        struct tas *tas = snd_kcontrol_chip(kcontrol);
+
+        if (tas->cached_volume_l == ucontrol->value.integer.value[0]
+         && tas->cached_volume_r == ucontrol->value.integer.value[1])
+                return 0;
+
+        tas->cached_volume_l = ucontrol->value.integer.value[0];
+        tas->cached_volume_r = ucontrol->value.integer.value[1];
+        tas_set_volume(tas);
+        return 1;
+}
+
+static struct snd_kcontrol_new volume_control = {
+        .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+        .name = "Master Playback Volume",
+        .access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
+        .info = tas_snd_vol_info,
+        .get = tas_snd_vol_get,
+        .put = tas_snd_vol_put,
+};
+
+static int tas_snd_mute_info(struct snd_kcontrol *kcontrol,
+        struct snd_ctl_elem_info *uinfo)
+{
+        uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
+        uinfo->count = 2;
+        uinfo->value.integer.min = 0;
+        uinfo->value.integer.max = 1;
+        return 0;
+}
+
+static int tas_snd_mute_get(struct snd_kcontrol *kcontrol,
+        struct snd_ctl_elem_value *ucontrol)
+{
+        struct tas *tas = snd_kcontrol_chip(kcontrol);
+
+        ucontrol->value.integer.value[0] = !tas->muted_l;
+        ucontrol->value.integer.value[1] = !tas->muted_r;
+        return 0;
+}
+
+static int tas_snd_mute_put(struct snd_kcontrol *kcontrol,
+        struct snd_ctl_elem_value *ucontrol)
+{
+        struct tas *tas = snd_kcontrol_chip(kcontrol);
+
+        if (tas->muted_l == !ucontrol->value.integer.value[0]
+         && tas->muted_r == !ucontrol->value.integer.value[1])
+                return 0;
+
+        tas->muted_l = !ucontrol->value.integer.value[0];
+        tas->muted_r = !ucontrol->value.integer.value[1];
+        tas_set_volume(tas);
+        return 1;
+}
+
+static struct snd_kcontrol_new mute_control = {
+        .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+        .name = "Master Playback Switch",
+        .access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
+        .info = tas_snd_mute_info,
+        .get = tas_snd_mute_get,
+        .put = tas_snd_mute_put,
+};
+
+static int tas_snd_mixer_info(struct snd_kcontrol *kcontrol,
+        struct snd_ctl_elem_info *uinfo)
+{
+        uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+        uinfo->count = 2;
+        uinfo->value.integer.min = 0;
+        uinfo->value.integer.max = 177;
+        return 0;
+}
+
+static int tas_snd_mixer_get(struct snd_kcontrol *kcontrol,
+        struct snd_ctl_elem_value *ucontrol)
+{
+        struct tas *tas = snd_kcontrol_chip(kcontrol);
+        int idx = kcontrol->private_value;
+
+        ucontrol->value.integer.value[0] = tas->mixer_l[idx];
+        ucontrol->value.integer.value[1] = tas->mixer_r[idx];
+
+        return 0;
+}
+
+static int tas_snd_mixer_put(struct snd_kcontrol *kcontrol,
+        struct snd_ctl_elem_value *ucontrol)
+{
+        struct tas *tas = snd_kcontrol_chip(kcontrol);
+        int idx = kcontrol->private_value;
+
+        if (tas->mixer_l[idx] == ucontrol->value.integer.value[0]
+         && tas->mixer_r[idx] == ucontrol->value.integer.value[1])
+                return 0;
+
+        tas->mixer_l[idx] = ucontrol->value.integer.value[0];
+        tas->mixer_r[idx] = ucontrol->value.integer.value[1];
+
+        tas_set_mixer(tas);
+        return 1;
+}
+
+#define MIXER_CONTROL(n,descr,idx)                      \
+static struct snd_kcontrol_new n##_control = {          \
+        .iface = SNDRV_CTL_ELEM_IFACE_MIXER,            \
+        .name = descr " Playback Volume",               \
+        .access = SNDRV_CTL_ELEM_ACCESS_READWRITE,      \
+        .info = tas_snd_mixer_info,                     \
+        .get = tas_snd_mixer_get,                       \
+        .put = tas_snd_mixer_put,                       \
+        .private_value = idx,                           \
+}
+
+MIXER_CONTROL(pcm1, "PCM1", 0);
+MIXER_CONTROL(monitor, "Monitor", 2);
+
+static int tas_snd_capture_source_info(struct snd_kcontrol *kcontrol,
+        struct snd_ctl_elem_info *uinfo)
+{
+        static char *texts[] = { "Line-In", "Microphone" };
+
+        uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
+        uinfo->count = 1;
+        uinfo->value.enumerated.items = 2;
+        if (uinfo->value.enumerated.item > 1)
+                uinfo->value.enumerated.item = 1;
+        strcpy(uinfo->value.enumerated.name, texts[uinfo->value.enumerated.item]);
+        return 0;
+}
+
+static int tas_snd_capture_source_get(struct snd_kcontrol *kcontrol,
+        struct snd_ctl_elem_value *ucontrol)
+{
+        struct tas *tas = snd_kcontrol_chip(kcontrol);
+
+        ucontrol->value.enumerated.item[0] = !!(tas->acr & TAS_ACR_INPUT_B);
+        return 0;
+}
+
+static int tas_snd_capture_source_put(struct snd_kcontrol *kcontrol,
+        struct snd_ctl_elem_value *ucontrol)
+{
+        struct tas *tas = snd_kcontrol_chip(kcontrol);
+        int oldacr = tas->acr;
+
+        tas->acr &= ~TAS_ACR_INPUT_B;
+        if (ucontrol->value.enumerated.item[0])
+                tas->acr |= TAS_ACR_INPUT_B;
+        if (oldacr == tas->acr)
+                return 0;
+        tas_write_reg(tas, TAS_REG_ACR, 1, &tas->acr);
+        return 1;
+}
+
+static struct snd_kcontrol_new capture_source_control = {
+        .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+        /* If we name this 'Input Source', it properly shows up in
+         * alsamixer as a selection, * but it's shown under the
+         * 'Playback' category.
+         * If I name it 'Capture Source', it shows up in strange
+         * ways (two bools of which one can be selected at a
+         * time) but at least it's shown in the 'Capture'
+         * category.
+         * I was told that this was due to backward compatibility,
+         * but I don't understand then why the mangling is *not*
+         * done when I name it "Input Source".....
+         */
+        .name = "Capture Source",
+        .access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
+        .info = tas_snd_capture_source_info,
+        .get = tas_snd_capture_source_get,
+        .put = tas_snd_capture_source_put,
+};
+
+
+static struct transfer_info tas_transfers[] = {
+        {
+                /* input */
+                .formats = SNDRV_PCM_FMTBIT_S16_BE | SNDRV_PCM_FMTBIT_S16_BE |
+                           SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S24_BE,
+                .rates = SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000,
+                .transfer_in = 1,
+        },
+        {
+                /* output */
+                .formats = SNDRV_PCM_FMTBIT_S16_BE | SNDRV_PCM_FMTBIT_S16_BE |
+                           SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S24_BE,
+                .rates = SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000,
+                .transfer_in = 0,
+        },
+        {}
+};
+
+static int tas_usable(struct codec_info_item *cii,
+                      struct transfer_info *ti,
+                      struct transfer_info *out)
+{
+        return 1;
+}
+
+static int tas_reset_init(struct tas *tas)
+{
+        u8 tmp;
+        tas->codec.gpio->methods->set_hw_reset(tas->codec.gpio, 0);
+        msleep(1);
+        tas->codec.gpio->methods->set_hw_reset(tas->codec.gpio, 1);
+        msleep(1);
+        tas->codec.gpio->methods->set_hw_reset(tas->codec.gpio, 0);
+        msleep(1);
+
+        tas->acr &= ~TAS_ACR_ANALOG_PDOWN;
+        tas->acr |= TAS_ACR_B_MONAUREAL | TAS_ACR_B_MON_SEL_RIGHT;
+        if (tas_write_reg(tas, TAS_REG_ACR, 1, &tas->acr))
+                return -ENODEV;
+
+        tmp = TAS_MCS_SCLK64 | TAS_MCS_SPORT_MODE_I2S | TAS_MCS_SPORT_WL_24BIT;
+        if (tas_write_reg(tas, TAS_REG_MCS, 1, &tmp))
+                return -ENODEV;
+
+        tmp = 0;
+        if (tas_write_reg(tas, TAS_REG_MCS2, 1, &tmp))
+                return -ENODEV;
+
+        return 0;
+}
+
+/* we are controlled via i2c and assume that is always up
+ * If that wasn't the case, we'd have to suspend once
+ * our i2c device is suspended, and then take note of that! */
+static int tas_suspend(struct tas *tas)
+{
+        tas->acr |= TAS_ACR_ANALOG_PDOWN;
+        tas_write_reg(tas, TAS_REG_ACR, 1, &tas->acr);
+        return 0;
+}
+
+static int tas_resume(struct tas *tas)
+{
+        /* reset codec */
+        tas_reset_init(tas);
+        tas_set_volume(tas);
+        tas_set_mixer(tas);
+        return 0;
+}
+
+#ifdef CONFIG_PM
+static int _tas_suspend(struct codec_info_item *cii, pm_message_t state)
+{
+        return tas_suspend(cii->codec_data);
+}
+
+static int _tas_resume(struct codec_info_item *cii)
+{
+        return tas_resume(cii->codec_data);
+}
+#endif
+
+static struct codec_info tas_codec_info = {
+        .transfers = tas_transfers,
+        /* in theory, we can drive it at 512 too...
+         * but so far the framework doesn't allow
+         * for that and I don't see much point in it. */
+        .sysclock_factor = 256,
+        /* same here, could be 32 for just one 16 bit format */
+        .bus_factor = 64,
+        .owner = THIS_MODULE,
+        .usable = tas_usable,
+#ifdef CONFIG_PM
+        .suspend = _tas_suspend,
+        .resume = _tas_resume,
+#endif
+};
+
+static int tas_init_codec(struct aoa_codec *codec)
+{
+        struct tas *tas = codec_to_tas(codec);
+        int err;
+
+        if (!tas->codec.gpio || !tas->codec.gpio->methods) {
+                printk(KERN_ERR PFX "gpios not assigned!!\n");
+                return -EINVAL;
+        }
+
+        if (tas_reset_init(tas)) {
+                printk(KERN_ERR PFX "tas failed to initialise\n");
+                return -ENXIO;
+        }
+
+        if (tas->codec.soundbus_dev->attach_codec(tas->codec.soundbus_dev,
+                                                   aoa_get_card(),
+                                                   &tas_codec_info, tas)) {
+                printk(KERN_ERR PFX "error attaching tas to soundbus\n");
+                return -ENODEV;
+        }
+
+        if (aoa_snd_device_new(SNDRV_DEV_LOWLEVEL, tas, &ops)) {
+                printk(KERN_ERR PFX "failed to create tas snd device!\n");
+                return -ENODEV;
+        }
+        err = aoa_snd_ctl_add(snd_ctl_new1(&volume_control, tas));
+        if (err)
+                goto error;
+
+        err = aoa_snd_ctl_add(snd_ctl_new1(&mute_control, tas));
+        if (err)
+                goto error;
+
+        err = aoa_snd_ctl_add(snd_ctl_new1(&pcm1_control, tas));
+        if (err)
+                goto error;
+
+        err = aoa_snd_ctl_add(snd_ctl_new1(&monitor_control, tas));
+        if (err)
+                goto error;
+
+        err = aoa_snd_ctl_add(snd_ctl_new1(&capture_source_control, tas));
+        if (err)
+                goto error;
+
+        return 0;
+ error:
+        tas->codec.soundbus_dev->detach_codec(tas->codec.soundbus_dev, tas);
+        snd_device_free(aoa_get_card(), tas);
+        return err;
+}
+
+static void tas_exit_codec(struct aoa_codec *codec)
+{
+        struct tas *tas = codec_to_tas(codec);
+
+        if (!tas->codec.soundbus_dev)
+                return;
+        tas->codec.soundbus_dev->detach_codec(tas->codec.soundbus_dev, tas);
+}
+        
+
+static struct i2c_driver tas_driver;
+
+static int tas_create(struct i2c_adapter *adapter,
+                       struct device_node *node,
+                       int addr)
+{
+        struct tas *tas;
+
+        tas = kzalloc(sizeof(struct tas), GFP_KERNEL);
+
+        if (!tas)
+                return -ENOMEM;
+
+        tas->i2c.driver = &tas_driver;
+        tas->i2c.adapter = adapter;
+        tas->i2c.addr = addr;
+        strlcpy(tas->i2c.name, "tas audio codec", I2C_NAME_SIZE-1);
+
+        if (i2c_attach_client(&tas->i2c)) {
+                printk(KERN_ERR PFX "failed to attach to i2c\n");
+                goto fail;
+        }
+
+        strlcpy(tas->codec.name, "tas", MAX_CODEC_NAME_LEN-1);
+        tas->codec.owner = THIS_MODULE;
+        tas->codec.init = tas_init_codec;
+        tas->codec.exit = tas_exit_codec;
+        tas->codec.node = of_node_get(node);
+
+        if (aoa_codec_register(&tas->codec)) {
+                goto detach;
+        }
+        printk(KERN_DEBUG "snd-aoa-codec-tas: created and attached tas instance\n");
+        return 0;
+ detach:
+        i2c_detach_client(&tas->i2c);
+ fail:
+        kfree(tas);
+        return -EINVAL;
+}
+
+static int tas_i2c_attach(struct i2c_adapter *adapter)
+{
+        struct device_node *busnode, *dev = NULL;
+        struct pmac_i2c_bus *bus;
+
+        bus = pmac_i2c_adapter_to_bus(adapter);
+        if (bus == NULL)
+                return -ENODEV;
+        busnode = pmac_i2c_get_bus_node(bus);
+
+        while ((dev = of_get_next_child(busnode, dev)) != NULL) {
+                if (device_is_compatible(dev, "tas3004")) {
+                        u32 *addr;
+                        printk(KERN_DEBUG PFX "found tas3004\n");
+                        addr = (u32 *) get_property(dev, "reg", NULL);
+                        if (!addr)
+                                continue;
+                        return tas_create(adapter, dev, ((*addr) >> 1) & 0x7f);
+                }
+                /* older machines have no 'codec' node with a 'compatible'
+                 * property that says 'tas3004', they just have a 'deq'
+                 * node without any such property... */
+                if (strcmp(dev->name, "deq") == 0) {
+                        u32 *_addr, addr;
+                        printk(KERN_DEBUG PFX "found 'deq' node\n");
+                        _addr = (u32 *) get_property(dev, "i2c-address", NULL);
+                        if (!_addr)
+                                continue;
+                        addr = ((*_addr) >> 1) & 0x7f;
+                        /* now, if the address doesn't match any of the two
+                         * that a tas3004 can have, we cannot handle this.
+                         * I doubt it ever happens but hey. */
+                        if (addr != 0x34 && addr != 0x35)
+                                continue;
+                        return tas_create(adapter, dev, addr);
+                }
+        }
+        return -ENODEV;
+}
+
+static int tas_i2c_detach(struct i2c_client *client)
+{
+        struct tas *tas = container_of(client, struct tas, i2c);
+        int err;
+        u8 tmp = TAS_ACR_ANALOG_PDOWN;
+
+        if ((err = i2c_detach_client(client)))
+                return err;
+        aoa_codec_unregister(&tas->codec);
+        of_node_put(tas->codec.node);
+
+        /* power down codec chip */
+        tas_write_reg(tas, TAS_REG_ACR, 1, &tmp);
+
+        kfree(tas);
+        return 0;
+}
+
+static struct i2c_driver tas_driver = {
+        .driver = {
+                .name = "aoa_codec_tas",
+                .owner = THIS_MODULE,
+        },
+        .attach_adapter = tas_i2c_attach,
+        .detach_client = tas_i2c_detach,
+};
+
+static int __init tas_init(void)
+{
+        return i2c_add_driver(&tas_driver);
+}
+
+static void __exit tas_exit(void)
+{
+        i2c_del_driver(&tas_driver);
+}
+
+module_init(tas_init);
+module_exit(tas_exit);