Commit 3a691b28 authored by Clemens Ladisch's avatar Clemens Ladisch Committed by Takashi Iwai

ALSA: add Apple iSight microphone driver

This adds an experimental driver for the front and rear microphones of
the Apple iSight web camera.
Signed-off-by: default avatarClemens Ladisch <clemens@ladisch.de>
Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent d7ba858a
......@@ -22,4 +22,16 @@ config SND_FIREWIRE_SPEAKERS
To compile this driver as a module, choose M here: the module
will be called snd-firewire-speakers.
config SND_ISIGHT
tristate "Apple iSight microphone (EXPERIMENTAL)"
depends on EXPERIMENTAL
select SND_PCM
select SND_FIREWIRE_LIB
help
Say Y here to include support for the front and rear microphones
of the Apple iSight web camera.
To compile this driver as a module, choose M here: the module
will be called snd-isight.
endif # SND_FIREWIRE
snd-firewire-lib-objs := lib.o iso-resources.o packets-buffer.o \
fcp.o cmp.o amdtp.o
snd-firewire-speakers-objs := speakers.o
snd-isight-objs := isight.o
obj-$(CONFIG_SND_FIREWIRE_LIB) += snd-firewire-lib.o
obj-$(CONFIG_SND_FIREWIRE_SPEAKERS) += snd-firewire-speakers.o
obj-$(CONFIG_SND_ISIGHT) += snd-isight.o
/*
* Apple iSight audio driver
*
* Copyright (c) Clemens Ladisch <clemens@ladisch.de>
* Licensed under the terms of the GNU General Public License, version 2.
*/
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/firewire.h>
#include <linux/firewire-constants.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/mutex.h>
#include <linux/string.h>
#include <sound/control.h>
#include <sound/core.h>
#include <sound/initval.h>
#include <sound/pcm.h>
#include <sound/tlv.h>
#include "lib.h"
#include "iso-resources.h"
#include "packets-buffer.h"
#define OUI_APPLE 0x000a27
#define MODEL_APPLE_ISIGHT 0x000008
#define SW_ISIGHT_AUDIO 0x000010
#define REG_AUDIO_ENABLE 0x000
#define AUDIO_ENABLE 0x80000000
#define REG_DEF_AUDIO_GAIN 0x204
#define REG_GAIN_RAW_START 0x210
#define REG_GAIN_RAW_END 0x214
#define REG_GAIN_DB_START 0x218
#define REG_GAIN_DB_END 0x21c
#define REG_SAMPLE_RATE_INQUIRY 0x280
#define REG_ISO_TX_CONFIG 0x300
#define SPEED_SHIFT 16
#define REG_SAMPLE_RATE 0x400
#define RATE_48000 0x80000000
#define REG_GAIN 0x500
#define REG_MUTE 0x504
#define MAX_FRAMES_PER_PACKET 475
#define QUEUE_LENGTH 20
struct isight {
struct snd_card *card;
struct fw_unit *unit;
struct fw_device *device;
u64 audio_base;
struct fw_address_handler iris_handler;
struct snd_pcm_substream *pcm;
struct mutex mutex;
struct iso_packets_buffer buffer;
struct fw_iso_resources resources;
struct fw_iso_context *context;
bool pcm_running;
bool first_packet;
int packet_index;
u32 total_samples;
unsigned int buffer_pointer;
unsigned int period_counter;
s32 gain_min, gain_max;
unsigned int gain_tlv[4];
};
struct audio_payload {
__be32 sample_count;
__be32 signature;
__be32 sample_total;
__be32 reserved;
__be16 samples[2 * MAX_FRAMES_PER_PACKET];
};
MODULE_DESCRIPTION("iSight audio driver");
MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
MODULE_LICENSE("GPL v2");
static struct fw_iso_packet audio_packet = {
.payload_length = sizeof(struct audio_payload),
.interrupt = 1,
};
static void isight_update_pointers(struct isight *isight, unsigned int count)
{
struct snd_pcm_runtime *runtime = isight->pcm->runtime;
unsigned int ptr;
smp_wmb(); /* update buffer data before buffer pointer */
ptr = isight->buffer_pointer;
ptr += count;
if (ptr >= runtime->buffer_size)
ptr -= runtime->buffer_size;
ACCESS_ONCE(isight->buffer_pointer) = ptr;
isight->period_counter += count;
if (isight->period_counter >= runtime->period_size) {
isight->period_counter -= runtime->period_size;
snd_pcm_period_elapsed(isight->pcm);
}
}
static void isight_samples(struct isight *isight,
const __be16 *samples, unsigned int count)
{
struct snd_pcm_runtime *runtime;
unsigned int count1;
if (!ACCESS_ONCE(isight->pcm_running))
return;
runtime = isight->pcm->runtime;
if (isight->buffer_pointer + count <= runtime->buffer_size) {
memcpy(runtime->dma_area + isight->buffer_pointer * 4,
samples, count * 4);
} else {
count1 = runtime->buffer_size - isight->buffer_pointer;
memcpy(runtime->dma_area + isight->buffer_pointer * 4,
samples, count1 * 4);
samples += count1 * 2;
memcpy(runtime->dma_area, samples, (count - count1) * 4);
}
isight_update_pointers(isight, count);
}
static void isight_pcm_abort(struct isight *isight)
{
unsigned long flags;
snd_pcm_stream_lock_irqsave(isight->pcm, flags);
if (snd_pcm_running(isight->pcm))
snd_pcm_stop(isight->pcm, SNDRV_PCM_STATE_XRUN);
snd_pcm_stream_unlock_irqrestore(isight->pcm, flags);
}
static void isight_dropped_samples(struct isight *isight, unsigned int total)
{
struct snd_pcm_runtime *runtime;
u32 dropped;
unsigned int count1;
if (!ACCESS_ONCE(isight->pcm_running))
return;
runtime = isight->pcm->runtime;
dropped = total - isight->total_samples;
if (dropped < runtime->buffer_size) {
if (isight->buffer_pointer + dropped <= runtime->buffer_size) {
memset(runtime->dma_area + isight->buffer_pointer * 4,
0, dropped * 4);
} else {
count1 = runtime->buffer_size - isight->buffer_pointer;
memset(runtime->dma_area + isight->buffer_pointer * 4,
0, count1 * 4);
memset(runtime->dma_area, 0, (dropped - count1) * 4);
}
isight_update_pointers(isight, dropped);
} else {
isight_pcm_abort(isight);
}
}
static void isight_packet(struct fw_iso_context *context, u32 cycle,
size_t header_length, void *header, void *data)
{
struct isight *isight = data;
const struct audio_payload *payload;
unsigned int index, length, count, total;
int err;
if (isight->packet_index < 0)
return;
index = isight->packet_index;
payload = isight->buffer.packets[index].buffer;
length = be32_to_cpup(header) >> 16;
if (likely(length >= 16 &&
payload->signature == cpu_to_be32(0x73676874/*"sght"*/))) {
count = be32_to_cpu(payload->sample_count);
if (likely(count <= (length - 16) / 4)) {
total = be32_to_cpu(payload->sample_total);
if (unlikely(total != isight->total_samples)) {
if (!isight->first_packet)
isight_dropped_samples(isight, total);
isight->first_packet = false;
isight->total_samples = total;
}
isight_samples(isight, payload->samples, count);
isight->total_samples += count;
}
}
if (++index >= QUEUE_LENGTH)
index = 0;
err = fw_iso_context_queue(isight->context, &audio_packet,
&isight->buffer.iso_buffer,
isight->buffer.packets[index].offset);
if (err < 0) {
dev_err(&isight->unit->device, "queueing error: %d\n", err);
isight_pcm_abort(isight);
isight->packet_index = -1;
return;
}
isight->packet_index = index;
}
static int isight_connect(struct isight *isight)
{
int ch, err, rcode, errors = 0;
__be32 value;
retry_after_bus_reset:
ch = fw_iso_resources_allocate(&isight->resources,
sizeof(struct audio_payload),
isight->device->max_speed);
if (ch < 0) {
err = ch;
goto error;
}
value = cpu_to_be32(ch | (isight->device->max_speed << SPEED_SHIFT));
for (;;) {
rcode = fw_run_transaction(
isight->device->card,
TCODE_WRITE_QUADLET_REQUEST,
isight->device->node_id,
isight->resources.generation,
isight->device->max_speed,
isight->audio_base + REG_ISO_TX_CONFIG,
&value, 4);
if (rcode == RCODE_COMPLETE) {
return 0;
} else if (rcode == RCODE_GENERATION) {
fw_iso_resources_free(&isight->resources);
goto retry_after_bus_reset;
} else if (rcode_is_permanent_error(rcode) || ++errors >= 3) {
err = -EIO;
goto err_resources;
}
msleep(5);
}
err_resources:
fw_iso_resources_free(&isight->resources);
error:
return err;
}
static int isight_open(struct snd_pcm_substream *substream)
{
static const struct snd_pcm_hardware hardware = {
.info = SNDRV_PCM_INFO_MMAP |
SNDRV_PCM_INFO_MMAP_VALID |
SNDRV_PCM_INFO_BATCH |
SNDRV_PCM_INFO_INTERLEAVED |
SNDRV_PCM_INFO_BLOCK_TRANSFER,
.formats = SNDRV_PCM_FMTBIT_S16_BE,
.rates = SNDRV_PCM_RATE_48000,
.rate_min = 48000,
.rate_max = 48000,
.channels_min = 2,
.channels_max = 2,
.buffer_bytes_max = 4 * 1024 * 1024,
.period_bytes_min = MAX_FRAMES_PER_PACKET * 4,
.period_bytes_max = 1024 * 1024,
.periods_min = 2,
.periods_max = UINT_MAX,
};
struct isight *isight = substream->private_data;
substream->runtime->hw = hardware;
return iso_packets_buffer_init(&isight->buffer, isight->unit,
QUEUE_LENGTH,
sizeof(struct audio_payload),
DMA_FROM_DEVICE);
}
static int isight_close(struct snd_pcm_substream *substream)
{
struct isight *isight = substream->private_data;
iso_packets_buffer_destroy(&isight->buffer, isight->unit);
return 0;
}
static int isight_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *hw_params)
{
return snd_pcm_lib_alloc_vmalloc_buffer(substream,
params_buffer_bytes(hw_params));
}
static void isight_stop_streaming(struct isight *isight)
{
__be32 value;
if (!isight->context)
return;
fw_iso_context_stop(isight->context);
fw_iso_context_destroy(isight->context);
isight->context = NULL;
value = 0;
snd_fw_transaction(isight->unit, TCODE_WRITE_QUADLET_REQUEST,
isight->audio_base + REG_AUDIO_ENABLE,
&value, 4);
fw_iso_resources_free(&isight->resources);
}
static int isight_hw_free(struct snd_pcm_substream *substream)
{
struct isight *isight = substream->private_data;
mutex_lock(&isight->mutex);
isight_stop_streaming(isight);
mutex_unlock(&isight->mutex);
return snd_pcm_lib_free_vmalloc_buffer(substream);
}
static int isight_start_streaming(struct isight *isight)
{
__be32 sample_rate;
unsigned int i;
int err;
if (isight->context) {
if (isight->packet_index < 0)
isight_stop_streaming(isight);
else
return 0;
}
sample_rate = cpu_to_be32(RATE_48000);
err = snd_fw_transaction(isight->unit, TCODE_WRITE_QUADLET_REQUEST,
isight->audio_base + REG_SAMPLE_RATE,
&sample_rate, 4);
if (err < 0)
return err;
err = isight_connect(isight);
if (err < 0)
goto error;
isight->context = fw_iso_context_create(isight->device->card,
FW_ISO_CONTEXT_RECEIVE,
isight->resources.channel,
isight->device->max_speed,
4, isight_packet, isight);
if (IS_ERR(isight->context)) {
err = PTR_ERR(isight->context);
isight->context = NULL;
goto err_resources;
}
for (i = 0; i < QUEUE_LENGTH; ++i) {
err = fw_iso_context_queue(isight->context, &audio_packet,
&isight->buffer.iso_buffer,
isight->buffer.packets[i].offset);
if (err < 0)
goto err_context;
}
isight->first_packet = true;
isight->packet_index = 0;
err = fw_iso_context_start(isight->context, -1, 0,
FW_ISO_CONTEXT_MATCH_ALL_TAGS/*?*/);
if (err < 0)
goto err_context;
return 0;
err_context:
fw_iso_context_destroy(isight->context);
isight->context = NULL;
err_resources:
fw_iso_resources_free(&isight->resources);
error:
return err;
}
static int isight_prepare(struct snd_pcm_substream *substream)
{
struct isight *isight = substream->private_data;
int err;
isight->buffer_pointer = 0;
isight->period_counter = 0;
mutex_lock(&isight->mutex);
err = isight_start_streaming(isight);
mutex_unlock(&isight->mutex);
return err;
}
static int isight_trigger(struct snd_pcm_substream *substream, int cmd)
{
struct isight *isight = substream->private_data;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
ACCESS_ONCE(isight->pcm_running) = true;
break;
case SNDRV_PCM_TRIGGER_STOP:
ACCESS_ONCE(isight->pcm_running) = false;
break;
default:
return -EINVAL;
}
return 0;
}
static snd_pcm_uframes_t isight_pointer(struct snd_pcm_substream *substream)
{
struct isight *isight = substream->private_data;
return ACCESS_ONCE(isight->buffer_pointer);
}
static int isight_create_pcm(struct isight *isight)
{
static struct snd_pcm_ops ops = {
.open = isight_open,
.close = isight_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = isight_hw_params,
.hw_free = isight_hw_free,
.prepare = isight_prepare,
.trigger = isight_trigger,
.pointer = isight_pointer,
.page = snd_pcm_lib_get_vmalloc_page,
.mmap = snd_pcm_lib_mmap_vmalloc,
};
struct snd_pcm *pcm;
int err;
err = snd_pcm_new(isight->card, "iSight", 0, 0, 1, &pcm);
if (err < 0)
return err;
pcm->private_data = isight;
strcpy(pcm->name, "iSight");
isight->pcm = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
isight->pcm->ops = &ops;
return 0;
}
static int isight_gain_info(struct snd_kcontrol *ctl,
struct snd_ctl_elem_info *info)
{
struct isight *isight = ctl->private_data;
info->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
info->count = 1;
info->value.integer.min = isight->gain_min;
info->value.integer.max = isight->gain_max;
return 0;
}
static int isight_gain_get(struct snd_kcontrol *ctl,
struct snd_ctl_elem_value *value)
{
struct isight *isight = ctl->private_data;
__be32 gain;
int err;
err = snd_fw_transaction(isight->unit, TCODE_READ_QUADLET_REQUEST,
isight->audio_base + REG_GAIN, &gain, 4);
if (err < 0)
return err;
value->value.integer.value[0] = (s32)be32_to_cpu(gain);
return 0;
}
static int isight_gain_put(struct snd_kcontrol *ctl,
struct snd_ctl_elem_value *value)
{
struct isight *isight = ctl->private_data;
__be32 gain;
if (value->value.integer.value[0] < isight->gain_min ||
value->value.integer.value[0] > isight->gain_max)
return -EINVAL;
gain = cpu_to_be32(value->value.integer.value[0]);
return snd_fw_transaction(isight->unit, TCODE_WRITE_QUADLET_REQUEST,
isight->audio_base + REG_GAIN, &gain, 4);
}
static int isight_mute_get(struct snd_kcontrol *ctl,
struct snd_ctl_elem_value *value)
{
struct isight *isight = ctl->private_data;
__be32 mute;
int err;
err = snd_fw_transaction(isight->unit, TCODE_READ_QUADLET_REQUEST,
isight->audio_base + REG_MUTE, &mute, 4);
if (err < 0)
return err;
value->value.integer.value[0] = !mute;
return 0;
}
static int isight_mute_put(struct snd_kcontrol *ctl,
struct snd_ctl_elem_value *value)
{
struct isight *isight = ctl->private_data;
__be32 mute;
mute = (__force __be32)!value->value.integer.value[0];
return snd_fw_transaction(isight->unit, TCODE_WRITE_QUADLET_REQUEST,
isight->audio_base + REG_MUTE, &mute, 4);
}
static int isight_create_mixer(struct isight *isight)
{
static const struct snd_kcontrol_new gain_control = {
.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
.name = "Mic Capture Volume",
.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
SNDRV_CTL_ELEM_ACCESS_TLV_READ,
.info = isight_gain_info,
.get = isight_gain_get,
.put = isight_gain_put,
};
static const struct snd_kcontrol_new mute_control = {
.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
.name = "Mic Capture Switch",
.info = snd_ctl_boolean_mono_info,
.get = isight_mute_get,
.put = isight_mute_put,
};
__be32 value;
struct snd_kcontrol *ctl;
int err;
err = snd_fw_transaction(isight->unit, TCODE_READ_QUADLET_REQUEST,
isight->audio_base + REG_GAIN_RAW_START,
&value, 4);
if (err < 0)
return err;
isight->gain_min = be32_to_cpu(value);
err = snd_fw_transaction(isight->unit, TCODE_READ_QUADLET_REQUEST,
isight->audio_base + REG_GAIN_RAW_END,
&value, 4);
if (err < 0)
return err;
isight->gain_max = be32_to_cpu(value);
isight->gain_tlv[0] = SNDRV_CTL_TLVT_DB_MINMAX;
isight->gain_tlv[1] = 2 * sizeof(unsigned int);
err = snd_fw_transaction(isight->unit, TCODE_READ_QUADLET_REQUEST,
isight->audio_base + REG_GAIN_DB_START,
&value, 4);
if (err < 0)
return err;
isight->gain_tlv[2] = (s32)be32_to_cpu(value) * 100;
err = snd_fw_transaction(isight->unit, TCODE_READ_QUADLET_REQUEST,
isight->audio_base + REG_GAIN_DB_END,
&value, 4);
if (err < 0)
return err;
isight->gain_tlv[3] = (s32)be32_to_cpu(value) * 100;
ctl = snd_ctl_new1(&gain_control, isight);
if (ctl)
ctl->tlv.p = isight->gain_tlv;
err = snd_ctl_add(isight->card, ctl);
if (err < 0)
return err;
err = snd_ctl_add(isight->card, snd_ctl_new1(&mute_control, isight));
if (err < 0)
return err;
return 0;
}
static void isight_card_free(struct snd_card *card)
{
struct isight *isight = card->private_data;
fw_iso_resources_destroy(&isight->resources);
fw_unit_put(isight->unit);
fw_device_put(isight->device);
mutex_destroy(&isight->mutex);
}
static u64 get_unit_base(struct fw_unit *unit)
{
struct fw_csr_iterator i;
int key, value;
fw_csr_iterator_init(&i, unit->directory);
while (fw_csr_iterator_next(&i, &key, &value))
if (key == CSR_OFFSET)
return CSR_REGISTER_BASE + value * 4;
return 0;
}
static int isight_probe(struct device *unit_dev)
{
struct fw_unit *unit = fw_unit(unit_dev);
struct fw_device *fw_dev = fw_parent_device(unit);
struct snd_card *card;
struct isight *isight;
int err;
err = snd_card_create(-1, NULL, THIS_MODULE, sizeof(*isight), &card);
if (err < 0)
return err;
snd_card_set_dev(card, unit_dev);
isight = card->private_data;
isight->card = card;
mutex_init(&isight->mutex);
isight->unit = fw_unit_get(unit);
isight->device = fw_device_get(fw_dev);
isight->audio_base = get_unit_base(unit);
if (!isight->audio_base) {
dev_err(&unit->device, "audio unit base not found\n");
err = -ENXIO;
goto err_unit;
}
fw_iso_resources_init(&isight->resources, unit);
card->private_free = isight_card_free;
strcpy(card->driver, "iSight");
strcpy(card->shortname, "Apple iSight");
snprintf(card->longname, sizeof(card->longname),
"Apple iSight (GUID %08x%08x) at %s, S%d",
fw_dev->config_rom[3], fw_dev->config_rom[4],
dev_name(&unit->device), 100 << fw_dev->max_speed);
strcpy(card->mixername, "iSight");
err = isight_create_pcm(isight);
if (err < 0)
goto error;
err = isight_create_mixer(isight);
if (err < 0)
goto error;
err = snd_card_register(card);
if (err < 0)
goto error;
dev_set_drvdata(unit_dev, isight);
return 0;
err_unit:
fw_unit_put(isight->unit);
fw_device_put(isight->device);
mutex_destroy(&isight->mutex);
error:
snd_card_free(card);
return err;
}
static int isight_remove(struct device *dev)
{
struct isight *isight = dev_get_drvdata(dev);
snd_card_disconnect(isight->card);
mutex_lock(&isight->mutex);
isight_pcm_abort(isight);
isight_stop_streaming(isight);
mutex_unlock(&isight->mutex);
snd_card_free_when_closed(isight->card);
return 0;
}
static void isight_bus_reset(struct fw_unit *unit)
{
struct isight *isight = dev_get_drvdata(&unit->device);
mutex_lock(&isight->mutex);
if (fw_iso_resources_update(&isight->resources) < 0) {
isight_pcm_abort(isight);
isight_stop_streaming(isight);
}
mutex_unlock(&isight->mutex);
}
static const struct ieee1394_device_id isight_id_table[] = {
{
.match_flags = IEEE1394_MATCH_SPECIFIER_ID |
IEEE1394_MATCH_VERSION,
.specifier_id = OUI_APPLE,
.version = SW_ISIGHT_AUDIO,
},
{ }
};
MODULE_DEVICE_TABLE(ieee1394, isight_id_table);
static struct fw_driver isight_driver = {
.driver = {
.owner = THIS_MODULE,
.name = KBUILD_MODNAME,
.bus = &fw_bus_type,
.probe = isight_probe,
.remove = isight_remove,
},
.update = isight_bus_reset,
.id_table = isight_id_table,
};
static int __init alsa_isight_init(void)
{
return driver_register(&isight_driver.driver);
}
static void __exit alsa_isight_exit(void)
{
driver_unregister(&isight_driver.driver);
}
module_init(alsa_isight_init);
module_exit(alsa_isight_exit);
......@@ -36,6 +36,7 @@ int fw_iso_resources_init(struct fw_iso_resources *r, struct fw_unit *unit)
return 0;
}
EXPORT_SYMBOL(fw_iso_resources_init);
/**
* fw_iso_resources_destroy - destroy a resource manager
......@@ -48,6 +49,7 @@ void fw_iso_resources_destroy(struct fw_iso_resources *r)
mutex_destroy(&r->mutex);
fw_unit_put(r->unit);
}
EXPORT_SYMBOL(fw_iso_resources_destroy);
static unsigned int packet_bandwidth(unsigned int max_payload_bytes, int speed)
{
......@@ -152,6 +154,7 @@ int fw_iso_resources_allocate(struct fw_iso_resources *r,
return channel;
}
EXPORT_SYMBOL(fw_iso_resources_allocate);
/**
* fw_iso_resources_update - update resource allocations after a bus reset
......@@ -203,6 +206,7 @@ int fw_iso_resources_update(struct fw_iso_resources *r)
return channel;
}
EXPORT_SYMBOL(fw_iso_resources_update);
/**
* fw_iso_resources_free - frees allocated resources
......@@ -230,3 +234,4 @@ void fw_iso_resources_free(struct fw_iso_resources *r)
mutex_unlock(&r->mutex);
}
EXPORT_SYMBOL(fw_iso_resources_free);
......@@ -60,6 +60,7 @@ int iso_packets_buffer_init(struct iso_packets_buffer *b, struct fw_unit *unit,
error:
return err;
}
EXPORT_SYMBOL(iso_packets_buffer_init);
/**
* iso_packets_buffer_destroy - frees packet buffer resources
......@@ -72,3 +73,4 @@ void iso_packets_buffer_destroy(struct iso_packets_buffer *b,
fw_iso_buffer_destroy(&b->iso_buffer, fw_parent_device(unit)->card);
kfree(b->packets);
}
EXPORT_SYMBOL(iso_packets_buffer_destroy);
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