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path: root/drivers/media/usb/cx231xx/cx231xx-audio.c
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Diffstat (limited to 'drivers/media/usb/cx231xx/cx231xx-audio.c')
-rw-r--r--drivers/media/usb/cx231xx/cx231xx-audio.c780
1 files changed, 780 insertions, 0 deletions
diff --git a/drivers/media/usb/cx231xx/cx231xx-audio.c b/drivers/media/usb/cx231xx/cx231xx-audio.c
new file mode 100644
index 000000000000..b4c99c7270cf
--- /dev/null
+++ b/drivers/media/usb/cx231xx/cx231xx-audio.c
@@ -0,0 +1,780 @@
+/*
+ * Conexant Cx231xx audio extension
+ *
+ * Copyright (C) 2008 <srinivasa.deevi at conexant dot com>
+ * Based on em28xx driver
+ *
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/usb.h>
+#include <linux/init.h>
+#include <linux/sound.h>
+#include <linux/spinlock.h>
+#include <linux/soundcard.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/proc_fs.h>
+#include <linux/module.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/info.h>
+#include <sound/initval.h>
+#include <sound/control.h>
+#include <media/v4l2-common.h>
+#include "cx231xx.h"
+
+static int debug;
+module_param(debug, int, 0644);
+MODULE_PARM_DESC(debug, "activates debug info");
+
+#define dprintk(fmt, arg...) do { \
+ if (debug) \
+ printk(KERN_INFO "cx231xx-audio %s: " fmt, \
+ __func__, ##arg); \
+ } while (0)
+
+static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
+
+static int cx231xx_isoc_audio_deinit(struct cx231xx *dev)
+{
+ int i;
+
+ dprintk("Stopping isoc\n");
+
+ for (i = 0; i < CX231XX_AUDIO_BUFS; i++) {
+ if (dev->adev.urb[i]) {
+ if (!irqs_disabled())
+ usb_kill_urb(dev->adev.urb[i]);
+ else
+ usb_unlink_urb(dev->adev.urb[i]);
+
+ usb_free_urb(dev->adev.urb[i]);
+ dev->adev.urb[i] = NULL;
+
+ kfree(dev->adev.transfer_buffer[i]);
+ dev->adev.transfer_buffer[i] = NULL;
+ }
+ }
+
+ return 0;
+}
+
+static int cx231xx_bulk_audio_deinit(struct cx231xx *dev)
+{
+ int i;
+
+ dprintk("Stopping bulk\n");
+
+ for (i = 0; i < CX231XX_AUDIO_BUFS; i++) {
+ if (dev->adev.urb[i]) {
+ if (!irqs_disabled())
+ usb_kill_urb(dev->adev.urb[i]);
+ else
+ usb_unlink_urb(dev->adev.urb[i]);
+
+ usb_free_urb(dev->adev.urb[i]);
+ dev->adev.urb[i] = NULL;
+
+ kfree(dev->adev.transfer_buffer[i]);
+ dev->adev.transfer_buffer[i] = NULL;
+ }
+ }
+
+ return 0;
+}
+
+static void cx231xx_audio_isocirq(struct urb *urb)
+{
+ struct cx231xx *dev = urb->context;
+ int i;
+ unsigned int oldptr;
+ int period_elapsed = 0;
+ int status;
+ unsigned char *cp;
+ unsigned int stride;
+ struct snd_pcm_substream *substream;
+ struct snd_pcm_runtime *runtime;
+
+ if (dev->state & DEV_DISCONNECTED)
+ return;
+
+ switch (urb->status) {
+ case 0: /* success */
+ case -ETIMEDOUT: /* NAK */
+ break;
+ case -ECONNRESET: /* kill */
+ case -ENOENT:
+ case -ESHUTDOWN:
+ return;
+ default: /* error */
+ dprintk("urb completition error %d.\n", urb->status);
+ break;
+ }
+
+ if (atomic_read(&dev->stream_started) == 0)
+ return;
+
+ if (dev->adev.capture_pcm_substream) {
+ substream = dev->adev.capture_pcm_substream;
+ runtime = substream->runtime;
+ stride = runtime->frame_bits >> 3;
+
+ for (i = 0; i < urb->number_of_packets; i++) {
+ int length = urb->iso_frame_desc[i].actual_length /
+ stride;
+ cp = (unsigned char *)urb->transfer_buffer +
+ urb->iso_frame_desc[i].offset;
+
+ if (!length)
+ continue;
+
+ oldptr = dev->adev.hwptr_done_capture;
+ if (oldptr + length >= runtime->buffer_size) {
+ unsigned int cnt;
+
+ cnt = runtime->buffer_size - oldptr;
+ memcpy(runtime->dma_area + oldptr * stride, cp,
+ cnt * stride);
+ memcpy(runtime->dma_area, cp + cnt * stride,
+ length * stride - cnt * stride);
+ } else {
+ memcpy(runtime->dma_area + oldptr * stride, cp,
+ length * stride);
+ }
+
+ snd_pcm_stream_lock(substream);
+
+ dev->adev.hwptr_done_capture += length;
+ if (dev->adev.hwptr_done_capture >=
+ runtime->buffer_size)
+ dev->adev.hwptr_done_capture -=
+ runtime->buffer_size;
+
+ dev->adev.capture_transfer_done += length;
+ if (dev->adev.capture_transfer_done >=
+ runtime->period_size) {
+ dev->adev.capture_transfer_done -=
+ runtime->period_size;
+ period_elapsed = 1;
+ }
+ snd_pcm_stream_unlock(substream);
+ }
+ if (period_elapsed)
+ snd_pcm_period_elapsed(substream);
+ }
+ urb->status = 0;
+
+ status = usb_submit_urb(urb, GFP_ATOMIC);
+ if (status < 0) {
+ cx231xx_errdev("resubmit of audio urb failed (error=%i)\n",
+ status);
+ }
+ return;
+}
+
+static void cx231xx_audio_bulkirq(struct urb *urb)
+{
+ struct cx231xx *dev = urb->context;
+ unsigned int oldptr;
+ int period_elapsed = 0;
+ int status;
+ unsigned char *cp;
+ unsigned int stride;
+ struct snd_pcm_substream *substream;
+ struct snd_pcm_runtime *runtime;
+
+ if (dev->state & DEV_DISCONNECTED)
+ return;
+
+ switch (urb->status) {
+ case 0: /* success */
+ case -ETIMEDOUT: /* NAK */
+ break;
+ case -ECONNRESET: /* kill */
+ case -ENOENT:
+ case -ESHUTDOWN:
+ return;
+ default: /* error */
+ dprintk("urb completition error %d.\n", urb->status);
+ break;
+ }
+
+ if (atomic_read(&dev->stream_started) == 0)
+ return;
+
+ if (dev->adev.capture_pcm_substream) {
+ substream = dev->adev.capture_pcm_substream;
+ runtime = substream->runtime;
+ stride = runtime->frame_bits >> 3;
+
+ if (1) {
+ int length = urb->actual_length /
+ stride;
+ cp = (unsigned char *)urb->transfer_buffer;
+
+ oldptr = dev->adev.hwptr_done_capture;
+ if (oldptr + length >= runtime->buffer_size) {
+ unsigned int cnt;
+
+ cnt = runtime->buffer_size - oldptr;
+ memcpy(runtime->dma_area + oldptr * stride, cp,
+ cnt * stride);
+ memcpy(runtime->dma_area, cp + cnt * stride,
+ length * stride - cnt * stride);
+ } else {
+ memcpy(runtime->dma_area + oldptr * stride, cp,
+ length * stride);
+ }
+
+ snd_pcm_stream_lock(substream);
+
+ dev->adev.hwptr_done_capture += length;
+ if (dev->adev.hwptr_done_capture >=
+ runtime->buffer_size)
+ dev->adev.hwptr_done_capture -=
+ runtime->buffer_size;
+
+ dev->adev.capture_transfer_done += length;
+ if (dev->adev.capture_transfer_done >=
+ runtime->period_size) {
+ dev->adev.capture_transfer_done -=
+ runtime->period_size;
+ period_elapsed = 1;
+ }
+ snd_pcm_stream_unlock(substream);
+ }
+ if (period_elapsed)
+ snd_pcm_period_elapsed(substream);
+ }
+ urb->status = 0;
+
+ status = usb_submit_urb(urb, GFP_ATOMIC);
+ if (status < 0) {
+ cx231xx_errdev("resubmit of audio urb failed (error=%i)\n",
+ status);
+ }
+ return;
+}
+
+static int cx231xx_init_audio_isoc(struct cx231xx *dev)
+{
+ int i, errCode;
+ int sb_size;
+
+ cx231xx_info("%s: Starting ISO AUDIO transfers\n", __func__);
+
+ if (dev->state & DEV_DISCONNECTED)
+ return -ENODEV;
+
+ sb_size = CX231XX_ISO_NUM_AUDIO_PACKETS * dev->adev.max_pkt_size;
+
+ for (i = 0; i < CX231XX_AUDIO_BUFS; i++) {
+ struct urb *urb;
+ int j, k;
+
+ dev->adev.transfer_buffer[i] = kmalloc(sb_size, GFP_ATOMIC);
+ if (!dev->adev.transfer_buffer[i])
+ return -ENOMEM;
+
+ memset(dev->adev.transfer_buffer[i], 0x80, sb_size);
+ urb = usb_alloc_urb(CX231XX_ISO_NUM_AUDIO_PACKETS, GFP_ATOMIC);
+ if (!urb) {
+ cx231xx_errdev("usb_alloc_urb failed!\n");
+ for (j = 0; j < i; j++) {
+ usb_free_urb(dev->adev.urb[j]);
+ kfree(dev->adev.transfer_buffer[j]);
+ }
+ return -ENOMEM;
+ }
+
+ urb->dev = dev->udev;
+ urb->context = dev;
+ urb->pipe = usb_rcvisocpipe(dev->udev,
+ dev->adev.end_point_addr);
+ urb->transfer_flags = URB_ISO_ASAP;
+ urb->transfer_buffer = dev->adev.transfer_buffer[i];
+ urb->interval = 1;
+ urb->complete = cx231xx_audio_isocirq;
+ urb->number_of_packets = CX231XX_ISO_NUM_AUDIO_PACKETS;
+ urb->transfer_buffer_length = sb_size;
+
+ for (j = k = 0; j < CX231XX_ISO_NUM_AUDIO_PACKETS;
+ j++, k += dev->adev.max_pkt_size) {
+ urb->iso_frame_desc[j].offset = k;
+ urb->iso_frame_desc[j].length = dev->adev.max_pkt_size;
+ }
+ dev->adev.urb[i] = urb;
+ }
+
+ for (i = 0; i < CX231XX_AUDIO_BUFS; i++) {
+ errCode = usb_submit_urb(dev->adev.urb[i], GFP_ATOMIC);
+ if (errCode < 0) {
+ cx231xx_isoc_audio_deinit(dev);
+ return errCode;
+ }
+ }
+
+ return errCode;
+}
+
+static int cx231xx_init_audio_bulk(struct cx231xx *dev)
+{
+ int i, errCode;
+ int sb_size;
+
+ cx231xx_info("%s: Starting BULK AUDIO transfers\n", __func__);
+
+ if (dev->state & DEV_DISCONNECTED)
+ return -ENODEV;
+
+ sb_size = CX231XX_NUM_AUDIO_PACKETS * dev->adev.max_pkt_size;
+
+ for (i = 0; i < CX231XX_AUDIO_BUFS; i++) {
+ struct urb *urb;
+ int j;
+
+ dev->adev.transfer_buffer[i] = kmalloc(sb_size, GFP_ATOMIC);
+ if (!dev->adev.transfer_buffer[i])
+ return -ENOMEM;
+
+ memset(dev->adev.transfer_buffer[i], 0x80, sb_size);
+ urb = usb_alloc_urb(CX231XX_NUM_AUDIO_PACKETS, GFP_ATOMIC);
+ if (!urb) {
+ cx231xx_errdev("usb_alloc_urb failed!\n");
+ for (j = 0; j < i; j++) {
+ usb_free_urb(dev->adev.urb[j]);
+ kfree(dev->adev.transfer_buffer[j]);
+ }
+ return -ENOMEM;
+ }
+
+ urb->dev = dev->udev;
+ urb->context = dev;
+ urb->pipe = usb_rcvbulkpipe(dev->udev,
+ dev->adev.end_point_addr);
+ urb->transfer_flags = 0;
+ urb->transfer_buffer = dev->adev.transfer_buffer[i];
+ urb->complete = cx231xx_audio_bulkirq;
+ urb->transfer_buffer_length = sb_size;
+
+ dev->adev.urb[i] = urb;
+
+ }
+
+ for (i = 0; i < CX231XX_AUDIO_BUFS; i++) {
+ errCode = usb_submit_urb(dev->adev.urb[i], GFP_ATOMIC);
+ if (errCode < 0) {
+ cx231xx_bulk_audio_deinit(dev);
+ return errCode;
+ }
+ }
+
+ return errCode;
+}
+
+static int snd_pcm_alloc_vmalloc_buffer(struct snd_pcm_substream *subs,
+ size_t size)
+{
+ struct snd_pcm_runtime *runtime = subs->runtime;
+
+ dprintk("Allocating vbuffer\n");
+ if (runtime->dma_area) {
+ if (runtime->dma_bytes > size)
+ return 0;
+
+ vfree(runtime->dma_area);
+ }
+ runtime->dma_area = vmalloc(size);
+ if (!runtime->dma_area)
+ return -ENOMEM;
+
+ runtime->dma_bytes = size;
+
+ return 0;
+}
+
+static struct snd_pcm_hardware snd_cx231xx_hw_capture = {
+ .info = SNDRV_PCM_INFO_BLOCK_TRANSFER |
+ SNDRV_PCM_INFO_MMAP |
+ SNDRV_PCM_INFO_INTERLEAVED |
+ SNDRV_PCM_INFO_MMAP_VALID,
+
+ .formats = SNDRV_PCM_FMTBIT_S16_LE,
+
+ .rates = SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_KNOT,
+
+ .rate_min = 48000,
+ .rate_max = 48000,
+ .channels_min = 2,
+ .channels_max = 2,
+ .buffer_bytes_max = 62720 * 8, /* just about the value in usbaudio.c */
+ .period_bytes_min = 64, /* 12544/2, */
+ .period_bytes_max = 12544,
+ .periods_min = 2,
+ .periods_max = 98, /* 12544, */
+};
+
+static int snd_cx231xx_capture_open(struct snd_pcm_substream *substream)
+{
+ struct cx231xx *dev = snd_pcm_substream_chip(substream);
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ int ret = 0;
+
+ dprintk("opening device and trying to acquire exclusive lock\n");
+
+ if (!dev) {
+ cx231xx_errdev("BUG: cx231xx can't find device struct."
+ " Can't proceed with open\n");
+ return -ENODEV;
+ }
+
+ if (dev->state & DEV_DISCONNECTED) {
+ cx231xx_errdev("Can't open. the device was removed.\n");
+ return -ENODEV;
+ }
+
+ /* Sets volume, mute, etc */
+ dev->mute = 0;
+
+ /* set alternate setting for audio interface */
+ /* 1 - 48000 samples per sec */
+ mutex_lock(&dev->lock);
+ if (dev->USE_ISO)
+ ret = cx231xx_set_alt_setting(dev, INDEX_AUDIO, 1);
+ else
+ ret = cx231xx_set_alt_setting(dev, INDEX_AUDIO, 0);
+ mutex_unlock(&dev->lock);
+ if (ret < 0) {
+ cx231xx_errdev("failed to set alternate setting !\n");
+
+ return ret;
+ }
+
+ runtime->hw = snd_cx231xx_hw_capture;
+
+ mutex_lock(&dev->lock);
+ /* inform hardware to start streaming */
+ ret = cx231xx_capture_start(dev, 1, Audio);
+
+ dev->adev.users++;
+ mutex_unlock(&dev->lock);
+
+ snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
+ dev->adev.capture_pcm_substream = substream;
+ runtime->private_data = dev;
+
+ return 0;
+}
+
+static int snd_cx231xx_pcm_close(struct snd_pcm_substream *substream)
+{
+ int ret;
+ struct cx231xx *dev = snd_pcm_substream_chip(substream);
+
+ dprintk("closing device\n");
+
+ /* inform hardware to stop streaming */
+ mutex_lock(&dev->lock);
+ ret = cx231xx_capture_start(dev, 0, Audio);
+
+ /* set alternate setting for audio interface */
+ /* 1 - 48000 samples per sec */
+ ret = cx231xx_set_alt_setting(dev, INDEX_AUDIO, 0);
+ if (ret < 0) {
+ cx231xx_errdev("failed to set alternate setting !\n");
+
+ mutex_unlock(&dev->lock);
+ return ret;
+ }
+
+ dev->mute = 1;
+ dev->adev.users--;
+ mutex_unlock(&dev->lock);
+
+ if (dev->adev.users == 0 && dev->adev.shutdown == 1) {
+ dprintk("audio users: %d\n", dev->adev.users);
+ dprintk("disabling audio stream!\n");
+ dev->adev.shutdown = 0;
+ dprintk("released lock\n");
+ if (atomic_read(&dev->stream_started) > 0) {
+ atomic_set(&dev->stream_started, 0);
+ schedule_work(&dev->wq_trigger);
+ }
+ }
+ return 0;
+}
+
+static int snd_cx231xx_hw_capture_params(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *hw_params)
+{
+ int ret;
+
+ dprintk("Setting capture parameters\n");
+
+ ret = snd_pcm_alloc_vmalloc_buffer(substream,
+ params_buffer_bytes(hw_params));
+#if 0
+ /* TODO: set up cx231xx audio chip to deliver the correct audio format,
+ current default is 48000hz multiplexed => 96000hz mono
+ which shouldn't matter since analogue TV only supports mono */
+ unsigned int channels, rate, format;
+
+ format = params_format(hw_params);
+ rate = params_rate(hw_params);
+ channels = params_channels(hw_params);
+#endif
+
+ return ret;
+}
+
+static int snd_cx231xx_hw_capture_free(struct snd_pcm_substream *substream)
+{
+ struct cx231xx *dev = snd_pcm_substream_chip(substream);
+
+ dprintk("Stop capture, if needed\n");
+
+ if (atomic_read(&dev->stream_started) > 0) {
+ atomic_set(&dev->stream_started, 0);
+ schedule_work(&dev->wq_trigger);
+ }
+
+ return 0;
+}
+
+static int snd_cx231xx_prepare(struct snd_pcm_substream *substream)
+{
+ struct cx231xx *dev = snd_pcm_substream_chip(substream);
+
+ dev->adev.hwptr_done_capture = 0;
+ dev->adev.capture_transfer_done = 0;
+
+ return 0;
+}
+
+static void audio_trigger(struct work_struct *work)
+{
+ struct cx231xx *dev = container_of(work, struct cx231xx, wq_trigger);
+
+ if (atomic_read(&dev->stream_started)) {
+ dprintk("starting capture");
+ if (is_fw_load(dev) == 0)
+ cx25840_call(dev, core, load_fw);
+ if (dev->USE_ISO)
+ cx231xx_init_audio_isoc(dev);
+ else
+ cx231xx_init_audio_bulk(dev);
+ } else {
+ dprintk("stopping capture");
+ cx231xx_isoc_audio_deinit(dev);
+ }
+}
+
+static int snd_cx231xx_capture_trigger(struct snd_pcm_substream *substream,
+ int cmd)
+{
+ struct cx231xx *dev = snd_pcm_substream_chip(substream);
+ int retval = 0;
+
+ if (dev->state & DEV_DISCONNECTED)
+ return -ENODEV;
+
+ spin_lock(&dev->adev.slock);
+ switch (cmd) {
+ case SNDRV_PCM_TRIGGER_START:
+ atomic_set(&dev->stream_started, 1);
+ break;
+ case SNDRV_PCM_TRIGGER_STOP:
+ atomic_set(&dev->stream_started, 0);
+ break;
+ default:
+ retval = -EINVAL;
+ break;
+ }
+ spin_unlock(&dev->adev.slock);
+
+ schedule_work(&dev->wq_trigger);
+
+ return retval;
+}
+
+static snd_pcm_uframes_t snd_cx231xx_capture_pointer(struct snd_pcm_substream
+ *substream)
+{
+ struct cx231xx *dev;
+ unsigned long flags;
+ snd_pcm_uframes_t hwptr_done;
+
+ dev = snd_pcm_substream_chip(substream);
+
+ spin_lock_irqsave(&dev->adev.slock, flags);
+ hwptr_done = dev->adev.hwptr_done_capture;
+ spin_unlock_irqrestore(&dev->adev.slock, flags);
+
+ return hwptr_done;
+}
+
+static struct page *snd_pcm_get_vmalloc_page(struct snd_pcm_substream *subs,
+ unsigned long offset)
+{
+ void *pageptr = subs->runtime->dma_area + offset;
+
+ return vmalloc_to_page(pageptr);
+}
+
+static struct snd_pcm_ops snd_cx231xx_pcm_capture = {
+ .open = snd_cx231xx_capture_open,
+ .close = snd_cx231xx_pcm_close,
+ .ioctl = snd_pcm_lib_ioctl,
+ .hw_params = snd_cx231xx_hw_capture_params,
+ .hw_free = snd_cx231xx_hw_capture_free,
+ .prepare = snd_cx231xx_prepare,
+ .trigger = snd_cx231xx_capture_trigger,
+ .pointer = snd_cx231xx_capture_pointer,
+ .page = snd_pcm_get_vmalloc_page,
+};
+
+static int cx231xx_audio_init(struct cx231xx *dev)
+{
+ struct cx231xx_audio *adev = &dev->adev;
+ struct snd_pcm *pcm;
+ struct snd_card *card;
+ static int devnr;
+ int err;
+ struct usb_interface *uif;
+ int i, isoc_pipe = 0;
+
+ if (dev->has_alsa_audio != 1) {
+ /* This device does not support the extension (in this case
+ the device is expecting the snd-usb-audio module or
+ doesn't have analog audio support at all) */
+ return 0;
+ }
+
+ cx231xx_info("cx231xx-audio.c: probing for cx231xx "
+ "non standard usbaudio\n");
+
+ err = snd_card_create(index[devnr], "Cx231xx Audio", THIS_MODULE,
+ 0, &card);
+ if (err < 0)
+ return err;
+
+ spin_lock_init(&adev->slock);
+ err = snd_pcm_new(card, "Cx231xx Audio", 0, 0, 1, &pcm);
+ if (err < 0) {
+ snd_card_free(card);
+ return err;
+ }
+
+ snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
+ &snd_cx231xx_pcm_capture);
+ pcm->info_flags = 0;
+ pcm->private_data = dev;
+ strcpy(pcm->name, "Conexant cx231xx Capture");
+ snd_card_set_dev(card, &dev->udev->dev);
+ strcpy(card->driver, "Cx231xx-Audio");
+ strcpy(card->shortname, "Cx231xx Audio");
+ strcpy(card->longname, "Conexant cx231xx Audio");
+
+ INIT_WORK(&dev->wq_trigger, audio_trigger);
+
+ err = snd_card_register(card);
+ if (err < 0) {
+ snd_card_free(card);
+ return err;
+ }
+ adev->sndcard = card;
+ adev->udev = dev->udev;
+
+ /* compute alternate max packet sizes for Audio */
+ uif =
+ dev->udev->actconfig->interface[dev->current_pcb_config.
+ hs_config_info[0].interface_info.
+ audio_index + 1];
+
+ adev->end_point_addr =
+ le16_to_cpu(uif->altsetting[0].endpoint[isoc_pipe].desc.
+ bEndpointAddress);
+
+ adev->num_alt = uif->num_altsetting;
+ cx231xx_info("EndPoint Addr 0x%x, Alternate settings: %i\n",
+ adev->end_point_addr, adev->num_alt);
+ adev->alt_max_pkt_size = kmalloc(32 * adev->num_alt, GFP_KERNEL);
+
+ if (adev->alt_max_pkt_size == NULL) {
+ cx231xx_errdev("out of memory!\n");
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < adev->num_alt; i++) {
+ u16 tmp =
+ le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe].desc.
+ wMaxPacketSize);
+ adev->alt_max_pkt_size[i] =
+ (tmp & 0x07ff) * (((tmp & 0x1800) >> 11) + 1);
+ cx231xx_info("Alternate setting %i, max size= %i\n", i,
+ adev->alt_max_pkt_size[i]);
+ }
+
+ return 0;
+}
+
+static int cx231xx_audio_fini(struct cx231xx *dev)
+{
+ if (dev == NULL)
+ return 0;
+
+ if (dev->has_alsa_audio != 1) {
+ /* This device does not support the extension (in this case
+ the device is expecting the snd-usb-audio module or
+ doesn't have analog audio support at all) */
+ return 0;
+ }
+
+ if (dev->adev.sndcard) {
+ snd_card_free(dev->adev.sndcard);
+ kfree(dev->adev.alt_max_pkt_size);
+ dev->adev.sndcard = NULL;
+ }
+
+ return 0;
+}
+
+static struct cx231xx_ops audio_ops = {
+ .id = CX231XX_AUDIO,
+ .name = "Cx231xx Audio Extension",
+ .init = cx231xx_audio_init,
+ .fini = cx231xx_audio_fini,
+};
+
+static int __init cx231xx_alsa_register(void)
+{
+ return cx231xx_register_extension(&audio_ops);
+}
+
+static void __exit cx231xx_alsa_unregister(void)
+{
+ cx231xx_unregister_extension(&audio_ops);
+}
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Srinivasa Deevi <srinivasa.deevi@conexant.com>");
+MODULE_DESCRIPTION("Cx231xx Audio driver");
+
+module_init(cx231xx_alsa_register);
+module_exit(cx231xx_alsa_unregister);