V4L/DVB (6951): Integrates em28xx-audio.c into em28xx kernel module

Also fixes the remaining CodingStyle issues that Lindent didn't fix.

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

5 files changed, 365 insertions, 260 deletions

diff --git a/drivers/media/video/em28xx/Kconfig b/drivers/media/video/em28xx/Kconfig
index 813077b6ef7..abbd38c1ebb 100644
--- a/drivers/media/video/em28xx/Kconfig
+++ b/drivers/media/video/em28xx/Kconfig
@@ -11,3 +11,18 @@ config VIDEO_EM28XX
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called em28xx
+
+config VIDEO_EM28XX_ALSA
+	depends on VIDEO_EM28XX
+	tristate "Empia EM28xx ALSA audio module"
+	---help---
+	  This is an ALSA driver for some Empia 28xx based TV cards.
+
+	  This is not required for em2800/em2820/em2821 boards. However,
+	  newer em28xx devices uses Vendor Class for audio, instead of
+	  implementing the USB Audio Class. For those chips, this module
+	  will enable digital audio.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called em28xx-alsa
+
diff --git a/drivers/media/video/em28xx/Makefile b/drivers/media/video/em28xx/Makefile
index 7e7a93d75c3..0924550992d 100644
--- a/drivers/media/video/em28xx/Makefile
+++ b/drivers/media/video/em28xx/Makefile
@@ -1,7 +1,10 @@
 em28xx-objs     := em28xx-video.o em28xx-i2c.o em28xx-cards.o em28xx-core.o \
 		   em28xx-input.o
 
+em28xx-alsa-objs := em28xx-audio.o
+
 obj-$(CONFIG_VIDEO_EM28XX) += em28xx.o
+obj-$(CONFIG_VIDEO_EM28XX_ALSA) += em28xx-alsa.o
 
 EXTRA_CFLAGS += -Idrivers/media/video
 EXTRA_CFLAGS += -Idrivers/media/dvb/dvb-core
diff --git a/drivers/media/video/em28xx/em28xx-audio.c b/drivers/media/video/em28xx/em28xx-audio.c
index c631cac4c5d..c91ff52aefa 100644
--- a/drivers/media/video/em28xx/em28xx-audio.c
+++ b/drivers/media/video/em28xx/em28xx-audio.c
@@ -3,6 +3,10 @@
  *
  *  Copyright (C) 2006 Markus Rechberger <mrechberger@gmail.com>
  *
+ *  Copyright (C) 2007 Mauro Carvalho Chehab <mchehab@infradead.org>
+ *	- Port to work with the in-kernel driver
+ *	- Several cleanups
+ *
  *  This driver is based on my previous au600 usb pstn audio driver
  *  and inherits all the copyrights
  *
@@ -30,7 +34,7 @@
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
 #include <linux/proc_fs.h>
-#include <linux/moduleparam.h>
+#include <linux/module.h>
 #include <sound/driver.h>
 #include <sound/core.h>
 #include <sound/pcm.h>
@@ -38,222 +42,52 @@
 #include <sound/info.h>
 #include <sound/initval.h>
 #include <sound/control.h>
-//#include <linux/video_decoder.h>
-//#include <media/tuner.h>
 #include <media/v4l2-common.h>
 #include "em28xx.h"
 
-static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
-static int em28xx_cmd(struct em28xx *dev, int cmd, int arg);
-
-static int snd_pcm_alloc_vmalloc_buffer(struct snd_pcm_substream *subs,
-					size_t size)
-{
-	struct snd_pcm_runtime *runtime = subs->runtime;
-	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 int debug;
+module_param(debug, int, 0644);
+MODULE_PARM_DESC(debug, "activates debug info");
 
-static struct snd_pcm_hardware snd_em28xx_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,
-};
+#define dprintk(fmt, arg...) do {					\
+	    if (debug)							\
+		printk(KERN_INFO "em28xx-audio %s: " fmt,		\
+				  __FUNCTION__, ##arg); 		\
+	} while (0)
 
-static int snd_em28xx_capture_open(struct snd_pcm_substream *substream)
-{
-	int ret = 0;
-	int mode;
-	struct em28xx *dev = snd_pcm_substream_chip(substream);
-	struct snd_pcm_runtime *runtime = substream->runtime;
-	printk("opening radio device and trying to acquire exclusive lock\n");
-	switch (dev->mode) {
-	case TUNER_STUB_DVBC_TV:
-	case TUNER_STUB_DVBT_TV:
-	case TUNER_STUB_ATSC_TV:
-		/* digital has no support for analog audio */
-		if (ret != 0) {
-			printk("device is already in use by DVB-T\n");
-			return -EINVAL;
-		} else {
-			struct v4l2_tuner tuner;
-			printk("switching device to FM mode\n");
-
-			mode = TUNER_STUB_RADIO;
-			memset(&tuner, 0x0, sizeof(struct v4l2_tuner));
-			tuner.type = V4L2_TUNER_RADIO;
-
-			/* enable GPIO for analog TV */
-			dev->em28xx_gpio_control(dev, EM28XX_MODE,
-						 (void *)mode);
-			dev->mode = mode;
-			/* upload firmware */
-			tuner_run_cmd(dev->tobj, TUNER_CMD_INIT, (void *)mode);
-
-			/* required for devices which have kerneldriver dependencies */
-//                              em28xx_config(dev);
-//                              em28xx_config_i2c(dev);
-
-			/* this is moreover to switch the decoder to FM */
-			em28xx_i2c_call_clients(dev, VIDIOC_S_TUNER, &tuner);
-
-			dev->em28xx_write_regs(dev, 0x0f, "\x87", 1);
-			ret = dev->em28xx_acquire(dev, EM28XX_RADIO, 1);
-			em28xx_i2c_call_clients(dev, VIDIOC_INT_RESET, 0);
-			/* TODO switch to FM mode */
-
-			printk("em28xx-audio: %d mode\n", mode);
-			tuner_run_cmd(dev->tobj, TUNER_CMD_G_MODE, &mode);
-			printk("retrieved mode from tuner: %d\n", mode);
-		}
-		break;
-
-	case TUNER_STUB_ANALOG_TV:
-		printk("em28xx-audio: device is currently in analog TV mode\n");
-		/* unmute by default */
-		dev->em28xx_write_regs(dev, 0x0f, "\x87", 1);
-		break;
-	case TUNER_STUB_RADIO:
-		/* check current mode and put a hard lock onto it */
-		printk
-		    ("em28xx-audio: device is currently in analogue FM mode\n");
-		/* unmute by default here */
-		dev->em28xx_write_regs(dev, 0x0f, "\x87", 1);
-		ret = dev->em28xx_acquire(dev, EM28XX_RADIO, 1);
-		if (ret == 0)
-			printk("device is locked in fmradio mode now\n");
-		break;
-	default:
-		printk("em28xx-audio: unhandled mode %d\n", dev->mode);
-	}
-
-	runtime->hw = snd_em28xx_hw_capture;
-	if (dev->alt == 0 && dev->adev->users == 0) {
-		int errCode;
-		dev->alt = 7;
-		errCode = usb_set_interface(dev->udev, 0, 7);
-		printk("changing alternate number to 7\n");
-	}
-	dev->adev->users++;
-	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_em28xx_pcm_close(struct snd_pcm_substream *substream)
-{
-	struct em28xx *dev = snd_pcm_substream_chip(substream);
-	int amode = 0;
-	dev->adev->users--;
-
-	/* decrease audio reference */
-	switch (dev->mode) {
-	case TUNER_STUB_ANALOG_TV:
-		amode = EM28XX_VIDEO;
-		break;
-	case TUNER_STUB_RADIO:
-		amode = EM28XX_RADIO;
-		break;
-	default:
-		printk("invalid mode: %d\n", dev->mode);
-		break;
-	}
-
-	dev->em28xx_acquire(dev, amode, 0);
-
-	if (dev->adev->users == 0 && dev->adev->shutdown == 1) {
-		printk("audio users: %d\n", dev->adev->users);
-		printk("disabling audio stream!\n");
-		dev->adev->shutdown = 0;
-		printk("released lock\n");
-		em28xx_cmd(dev, EM28XX_CAPTURE_STREAM_EN, 0);
-	}
-	return 0;
-}
+static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
 
-static int snd_em28xx_hw_capture_params(struct snd_pcm_substream *substream,
-					struct snd_pcm_hw_params *hw_params)
+static int em28xx_isoc_audio_deinit(struct em28xx *dev)
 {
-	unsigned int channels, rate, format;
-	int ret;
-	ret =
-	    snd_pcm_alloc_vmalloc_buffer(substream,
-					 params_buffer_bytes(hw_params));
-	format = params_format(hw_params);
-	rate = params_rate(hw_params);
-	channels = params_channels(hw_params);
-	/* TODO: set up em28xx 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 */
-	return 0;
-}
+	int i;
 
-static int snd_em28xx_hw_capture_free(struct snd_pcm_substream *substream)
-{
-	struct em28xx *dev = snd_pcm_substream_chip(substream);
-	if (dev->adev->capture_stream == STREAM_ON) {
-		em28xx_cmd(dev, EM28XX_CAPTURE_STREAM_EN, 0);
+	dprintk("Stopping isoc\n");
+	for (i = 0; i < EM28XX_AUDIO_BUFS; i++) {
+		usb_kill_urb(dev->adev->urb[i]);
+		usb_free_urb(dev->adev->urb[i]);
+		dev->adev->urb[i] = NULL;
 	}
-	return 0;
-}
 
-static int snd_em28xx_prepare(struct snd_pcm_substream *substream)
-{
 	return 0;
 }
 
-static int snd_em28xx_capture_trigger(struct snd_pcm_substream *substream,
-				      int cmd)
-{
-	struct em28xx *dev = snd_pcm_substream_chip(substream);
-	switch (cmd) {
-	case SNDRV_PCM_TRIGGER_START:
-		em28xx_cmd(dev, EM28XX_CAPTURE_STREAM_EN, 1);
-		return 0;
-	case SNDRV_PCM_TRIGGER_STOP:
-		dev->adev->shutdown = 1;
-		return 0;
-	default:
-		return -EINVAL;
-	}
-}
-
 static void em28xx_audio_isocirq(struct urb *urb)
 {
-	struct em28xx *dev = urb->context;
-	int i;
-	unsigned int oldptr;
-	unsigned long flags;
-	int period_elapsed = 0;
-	int status;
-	unsigned char *cp;
-	unsigned int stride;
+	struct em28xx            *dev = urb->context;
+	int                      i;
+	unsigned int             oldptr;
+	unsigned long            flags;
+	int                      period_elapsed = 0;
+	int                      status;
+	unsigned char            *cp;
+	unsigned int             stride;
 	struct snd_pcm_substream *substream;
-	struct snd_pcm_runtime *runtime;
+	struct snd_pcm_runtime   *runtime;
 	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;
@@ -264,6 +98,7 @@ static void em28xx_audio_isocirq(struct urb *urb)
 				continue;
 
 			spin_lock_irqsave(&dev->adev->slock, flags);
+
 			oldptr = dev->adev->hwptr_done_capture;
 			dev->adev->hwptr_done_capture += length;
 			if (dev->adev->hwptr_done_capture >=
@@ -278,6 +113,7 @@ static void em28xx_audio_isocirq(struct urb *urb)
 				    runtime->period_size;
 				period_elapsed = 1;
 			}
+
 			spin_unlock_irqrestore(&dev->adev->slock, flags);
 
 			if (oldptr + length >= runtime->buffer_size) {
@@ -292,82 +128,79 @@ static void em28xx_audio_isocirq(struct urb *urb)
 				       length * stride);
 			}
 		}
-		if (period_elapsed) {
+		if (period_elapsed)
 			snd_pcm_period_elapsed(substream);
-		}
 	}
 	urb->status = 0;
 
 	if (dev->adev->shutdown)
 		return;
 
-	if ((status = usb_submit_urb(urb, GFP_ATOMIC))) {
+	status = usb_submit_urb(urb, GFP_ATOMIC);
+	if (status < 0) {
 		em28xx_errdev("resubmit of audio urb failed (error=%i)\n",
 			      status);
 	}
 	return;
 }
 
-static int em28xx_isoc_audio_deinit(struct em28xx *dev)
-{
-	int i;
-	for (i = 0; i < EM28XX_AUDIO_BUFS; i++) {
-		usb_kill_urb(dev->adev->urb[i]);
-		usb_free_urb(dev->adev->urb[i]);
-		dev->adev->urb[i] = NULL;
-	}
-	return 0;
-}
-
 static int em28xx_init_audio_isoc(struct em28xx *dev)
 {
-	int i;
-	int errCode;
-	const int sb_size =
-	    EM28XX_NUM_AUDIO_PACKETS * EM28XX_AUDIO_MAX_PACKET_SIZE;
+	int       i, errCode;
+	const int sb_size = EM28XX_NUM_AUDIO_PACKETS *
+			    EM28XX_AUDIO_MAX_PACKET_SIZE;
+
+	dprintk("Starting isoc transfers\n");
 
 	for (i = 0; i < EM28XX_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]) {
+		if (!dev->adev->transfer_buffer[i])
 			return -ENOMEM;
-		}
+
 		memset(dev->adev->transfer_buffer[i], 0x80, sb_size);
 		urb = usb_alloc_urb(EM28XX_NUM_AUDIO_PACKETS, GFP_ATOMIC);
-		if (urb) {
-			urb->dev = dev->udev;
-			urb->context = dev;
-			urb->pipe = usb_rcvisocpipe(dev->udev, 0x83);
-			urb->transfer_flags = URB_ISO_ASAP;
-			urb->transfer_buffer = dev->adev->transfer_buffer[i];
-			urb->interval = 1;
-			urb->complete = em28xx_audio_isocirq;
-			urb->number_of_packets = EM28XX_NUM_AUDIO_PACKETS;
-			urb->transfer_buffer_length = sb_size;
-			for (j = k = 0; j < EM28XX_NUM_AUDIO_PACKETS;
-			     j++, k += EM28XX_AUDIO_MAX_PACKET_SIZE) {
-				urb->iso_frame_desc[j].offset = k;
-				urb->iso_frame_desc[j].length =
-				    EM28XX_AUDIO_MAX_PACKET_SIZE;
-			}
-			dev->adev->urb[i] = urb;
-		} else {
+		if (!urb)
 			return -ENOMEM;
+
+		urb->dev = dev->udev;
+		urb->context = dev;
+		urb->pipe = usb_rcvisocpipe(dev->udev, 0x83);
+		urb->transfer_flags = URB_ISO_ASAP;
+		urb->transfer_buffer = dev->adev->transfer_buffer[i];
+		urb->interval = 1;
+		urb->complete = em28xx_audio_isocirq;
+		urb->number_of_packets = EM28XX_NUM_AUDIO_PACKETS;
+		urb->transfer_buffer_length = sb_size;
+
+		for (j = k = 0; j < EM28XX_NUM_AUDIO_PACKETS;
+			     j++, k += EM28XX_AUDIO_MAX_PACKET_SIZE) {
+			urb->iso_frame_desc[j].offset = k;
+			urb->iso_frame_desc[j].length =
+			    EM28XX_AUDIO_MAX_PACKET_SIZE;
 		}
+		dev->adev->urb[i] = urb;
 	}
+
 	for (i = 0; i < EM28XX_AUDIO_BUFS; i++) {
 		errCode = usb_submit_urb(dev->adev->urb[i], GFP_ATOMIC);
 		if (errCode) {
 			em28xx_isoc_audio_deinit(dev);
+
 			return errCode;
 		}
 	}
+
 	return 0;
 }
 
 static int em28xx_cmd(struct em28xx *dev, int cmd, int arg)
 {
+	dprintk("%s transfer\n", (dev->adev->capture_stream == STREAM_ON)?
+				 "stop" : "start");
+
 	switch (cmd) {
 	case EM28XX_CAPTURE_STREAM_EN:
 		if (dev->adev->capture_stream == STREAM_OFF && arg == 1) {
@@ -377,8 +210,8 @@ static int em28xx_cmd(struct em28xx *dev, int cmd, int arg)
 			dev->adev->capture_stream = STREAM_OFF;
 			em28xx_isoc_audio_deinit(dev);
 		} else {
-			printk
-			    ("An underrun occured very likely... ignoring it\n");
+			printk(KERN_ERR "An underrun very likely occurred. "
+					"Ignoring it.\n");
 		}
 		return 0;
 	default:
@@ -386,13 +219,167 @@ static int em28xx_cmd(struct em28xx *dev, int cmd, int arg)
 	}
 }
 
+static int snd_pcm_alloc_vmalloc_buffer(struct snd_pcm_substream *subs,
+					size_t size)
+{
+	struct snd_pcm_runtime *runtime = subs->runtime;
+
+	dprintk("Alocating 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_em28xx_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_em28xx_capture_open(struct snd_pcm_substream *substream)
+{
+	struct em28xx *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");
+
+	/* Sets volume, mute, etc */
+	dev->mute = 0;
+	ret = em28xx_audio_analog_set(dev);
+	if (ret < 0)
+		goto err;
+
+	runtime->hw = snd_em28xx_hw_capture;
+	if (dev->alt == 0 && dev->adev->users == 0) {
+		int errCode;
+		dev->alt = 7;
+		errCode = usb_set_interface(dev->udev, 0, 7);
+		dprintk("changing alternate number to 7\n");
+	}
+
+	dev->adev->users++;
+
+	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
+	dev->adev->capture_pcm_substream = substream;
+	runtime->private_data = dev;
+
+	return 0;
+err:
+	printk(KERN_ERR "Error while configuring em28xx mixer\n");
+	return ret;
+}
+
+static int snd_em28xx_pcm_close(struct snd_pcm_substream *substream)
+{
+	struct em28xx *dev = snd_pcm_substream_chip(substream);
+	dev->adev->users--;
+
+	dprintk("closing device\n");
+
+	dev->mute = 1;
+	em28xx_audio_analog_set(dev);
+
+	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");
+		em28xx_cmd(dev, EM28XX_CAPTURE_STREAM_EN, 0);
+	}
+	return 0;
+}
+
+static int snd_em28xx_hw_capture_params(struct snd_pcm_substream *substream,
+					struct snd_pcm_hw_params *hw_params)
+{
+	unsigned int channels, rate, format;
+	int ret;
+
+	dprintk("Setting capture parameters\n");
+
+	ret = snd_pcm_alloc_vmalloc_buffer(substream,
+				params_buffer_bytes(hw_params));
+	format = params_format(hw_params);
+	rate = params_rate(hw_params);
+	channels = params_channels(hw_params);
+
+	/* TODO: set up em28xx 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 */
+	return 0;
+}
+
+static int snd_em28xx_hw_capture_free(struct snd_pcm_substream *substream)
+{
+	struct em28xx *dev = snd_pcm_substream_chip(substream);
+
+	dprintk("Stop capture, if needed\n");
+
+	if (dev->adev->capture_stream == STREAM_ON)
+		em28xx_cmd(dev, EM28XX_CAPTURE_STREAM_EN, 0);
+
+	return 0;
+}
+
+static int snd_em28xx_prepare(struct snd_pcm_substream *substream)
+{
+	return 0;
+}
+
+static int snd_em28xx_capture_trigger(struct snd_pcm_substream *substream,
+				      int cmd)
+{
+	struct em28xx *dev = snd_pcm_substream_chip(substream);
+
+	dprintk("Should %s capture\n", (cmd == SNDRV_PCM_TRIGGER_START)?
+				       "start": "stop");
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		em28xx_cmd(dev, EM28XX_CAPTURE_STREAM_EN, 1);
+		return 0;
+	case SNDRV_PCM_TRIGGER_STOP:
+		dev->adev->shutdown = 1;
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
 static snd_pcm_uframes_t snd_em28xx_capture_pointer(struct snd_pcm_substream
 						    *substream)
 {
 	struct em28xx *dev;
+
 	snd_pcm_uframes_t hwptr_done;
 	dev = snd_pcm_substream_chip(substream);
 	hwptr_done = dev->adev->hwptr_done_capture;
+
 	return hwptr_done;
 }
 
@@ -400,34 +387,38 @@ 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_em28xx_pcm_capture = {
-	.open = snd_em28xx_capture_open,
-	.close = snd_em28xx_pcm_close,
-	.ioctl = snd_pcm_lib_ioctl,
+	.open      = snd_em28xx_capture_open,
+	.close     = snd_em28xx_pcm_close,
+	.ioctl     = snd_pcm_lib_ioctl,
 	.hw_params = snd_em28xx_hw_capture_params,
-	.hw_free = snd_em28xx_hw_capture_free,
-	.prepare = snd_em28xx_prepare,
-	.trigger = snd_em28xx_capture_trigger,
-	.pointer = snd_em28xx_capture_pointer,
-	.page = snd_pcm_get_vmalloc_page,
+	.hw_free   = snd_em28xx_hw_capture_free,
+	.prepare   = snd_em28xx_prepare,
+	.trigger   = snd_em28xx_capture_trigger,
+	.pointer   = snd_em28xx_capture_pointer,
+	.page      = snd_pcm_get_vmalloc_page,
 };
 
 static int em28xx_audio_init(struct em28xx *dev)
 {
 	struct em28xx_audio *adev;
-	struct snd_pcm *pcm;
-	struct snd_card *card;
-	static int devnr;
-	int ret;
-	int err;
-	printk("em28xx-audio.c: probing for em28x1 non standard usbaudio\n");
-	printk("em28xx-audio.c: Copyright (C) 2006 Markus Rechberger\n");
+	struct snd_pcm      *pcm;
+	struct snd_card     *card;
+	static int          devnr;
+	int                 ret, err;
+
+	printk(KERN_INFO "em28xx-audio.c: probing for em28x1 "
+			 "non standard usbaudio\n");
+	printk(KERN_INFO "em28xx-audio.c: Copyright (C) 2006 Markus "
+			 "Rechberger\n");
+
 	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
 	if (!adev) {
-		printk("em28xx-audio.c: out of memory\n");
+		printk(KERN_ERR "em28xx-audio.c: out of memory\n");
 		return -1;
 	}
 	card = snd_card_new(index[devnr], "Em28xx Audio", THIS_MODULE, 0);
@@ -446,13 +437,15 @@ static int em28xx_audio_init(struct em28xx *dev)
 	strcpy(card->shortname, "Em28xx Audio");
 	strcpy(card->longname, "Empia Em28xx Audio");
 
-	if ((err = snd_card_register(card)) < 0) {
+	err = snd_card_register(card);
+	if (err < 0) {
 		snd_card_free(card);
 		return -ENOMEM;
 	}
 	adev->sndcard = card;
 	adev->udev = dev->udev;
 	dev->adev = adev;
+
 	return 0;
 }
 
@@ -460,16 +453,18 @@ static int em28xx_audio_fini(struct em28xx *dev)
 {
 	if (dev == NULL)
 		return 0;
+
 	if (dev->adev) {
 		snd_card_free(dev->adev->sndcard);
 		kfree(dev->adev);
 		dev->adev = NULL;
 	}
+
 	return 0;
 }
 
 static struct em28xx_ops audio_ops = {
-	.id = EM28XX_AUDIO,
+	.id   = EM28XX_AUDIO,
 	.name = "Em28xx Audio Extension",
 	.init = em28xx_audio_init,
 	.fini = em28xx_audio_fini,
@@ -478,7 +473,6 @@ static struct em28xx_ops audio_ops = {
 static int __init em28xx_alsa_register(void)
 {
 	request_module("em28xx");
-	request_module("tuner");
 	return em28xx_register_extension(&audio_ops);
 }
 
@@ -489,6 +483,7 @@ static void __exit em28xx_alsa_unregister(void)
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Markus Rechberger <mrechberger@gmail.com>");
+MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@infradead.org>");
 MODULE_DESCRIPTION("Em28xx Audio driver");
 
 module_init(em28xx_alsa_register);
diff --git a/drivers/media/video/em28xx/em28xx-video.c b/drivers/media/video/em28xx/em28xx-video.c
index 1a284cb18c2..caa4757b7eb 100644
--- a/drivers/media/video/em28xx/em28xx-video.c
+++ b/drivers/media/video/em28xx/em28xx-video.c
@@ -1599,9 +1599,48 @@ static const struct video_device em28xx_video_template = {
 	.current_norm               = V4L2_STD_PAL,
 };
 
-
 /******************************** usb interface *****************************************/
 
+
+static LIST_HEAD(em28xx_extension_devlist);
+static DEFINE_MUTEX(em28xx_extension_devlist_lock);
+
+int em28xx_register_extension(struct em28xx_ops *ops)
+{
+	struct em28xx *h, *dev = NULL;
+
+	list_for_each_entry(h, &em28xx_devlist, devlist)
+		dev = h;
+
+	mutex_lock(&em28xx_extension_devlist_lock);
+	list_add_tail(&ops->next, &em28xx_extension_devlist);
+	if (dev)
+		ops->init(dev);
+
+	printk(KERN_INFO "Em28xx: Initialized (%s) extension\n", ops->name);
+	mutex_unlock(&em28xx_extension_devlist_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL(em28xx_register_extension);
+
+void em28xx_unregister_extension(struct em28xx_ops *ops)
+{
+	struct em28xx *h, *dev = NULL;
+
+	list_for_each_entry(h, &em28xx_devlist, devlist)
+		dev = h;
+
+	if (dev)
+		ops->fini(dev);
+
+	mutex_lock(&em28xx_extension_devlist_lock);
+	printk(KERN_INFO "Em28xx: Removed (%s) extension\n", ops->name);
+	list_del(&ops->next);
+	mutex_unlock(&em28xx_extension_devlist_lock);
+}
+EXPORT_SYMBOL(em28xx_unregister_extension);
+
 /*
  * em28xx_init_dev()
  * allocates and inits the device structs, registers i2c bus and v4l device
@@ -1609,6 +1648,7 @@ static const struct video_device em28xx_video_template = {
 static int em28xx_init_dev(struct em28xx **devhandle, struct usb_device *udev,
 			   int minor)
 {
+	struct em28xx_ops *ops = NULL;
 	struct em28xx *dev = *devhandle;
 	int retval = -ENOMEM;
 	int errCode;
@@ -1742,6 +1782,15 @@ static int em28xx_init_dev(struct em28xx **devhandle, struct usb_device *udev,
 				dev->vdev->minor-MINOR_VFL_TYPE_GRABBER_MIN,
 				dev->vbi_dev->minor-MINOR_VFL_TYPE_VBI_MIN);
 
+	mutex_lock(&em28xx_extension_devlist_lock);
+	if (!list_empty(&em28xx_extension_devlist)) {
+		list_for_each_entry(ops, &em28xx_extension_devlist, next) {
+			if (ops->id)
+				ops->init(dev);
+		}
+	}
+	mutex_unlock(&em28xx_extension_devlist_lock);
+
 	return 0;
 }
 
@@ -1862,6 +1911,7 @@ static int em28xx_usb_probe(struct usb_interface *interface,
 static void em28xx_usb_disconnect(struct usb_interface *interface)
 {
 	struct em28xx *dev;
+	struct em28xx_ops *ops = NULL;
 
 	dev = usb_get_intfdata(interface);
 	usb_set_intfdata(interface, NULL);
@@ -1891,15 +1941,20 @@ static void em28xx_usb_disconnect(struct usb_interface *interface)
 		dev->state |= DEV_DISCONNECTED;
 		em28xx_release_resources(dev);
 	}
-
-
 	mutex_unlock(&dev->lock);
 
+	mutex_lock(&em28xx_extension_devlist_lock);
+	if (!list_empty(&em28xx_extension_devlist)) {
+		list_for_each_entry(ops, &em28xx_extension_devlist, next) {
+			ops->fini(dev);
+		}
+	}
+	mutex_unlock(&em28xx_extension_devlist_lock);
+
 	if (!dev->users) {
 		kfree(dev->alt_max_pkt_size);
 		kfree(dev);
 	}
-
 }
 
 static struct usb_driver em28xx_usb_driver = {
diff --git a/drivers/media/video/em28xx/em28xx.h b/drivers/media/video/em28xx/em28xx.h
index 1fb3c230e23..c2d9ae0ac61 100644
--- a/drivers/media/video/em28xx/em28xx.h
+++ b/drivers/media/video/em28xx/em28xx.h
@@ -212,6 +212,28 @@ enum em28xx_dev_state {
 	DEV_MISCONFIGURED = 0x04,
 };
 
+#define EM28XX_AUDIO_BUFS 5
+#define EM28XX_NUM_AUDIO_PACKETS 64
+#define EM28XX_AUDIO_MAX_PACKET_SIZE 196 /* static value */
+#define EM28XX_CAPTURE_STREAM_EN 1
+#define EM28XX_AUDIO   0x10
+
+struct em28xx_audio {
+	char name[50];
+	char *transfer_buffer[EM28XX_AUDIO_BUFS];
+	struct urb *urb[EM28XX_AUDIO_BUFS];
+	struct usb_device *udev;
+	unsigned int capture_transfer_done;
+	struct snd_pcm_substream   *capture_pcm_substream;
+
+	unsigned int hwptr_done_capture;
+	struct snd_card            *sndcard;
+
+	int users, shutdown;
+	enum em28xx_stream_state capture_stream;
+	spinlock_t slock;
+};
+
 /* main device struct */
 struct em28xx {
 	/* generic device properties */
@@ -266,6 +288,8 @@ struct em28xx {
 	unsigned long hash;	/* eeprom hash - for boards with generic ID */
 	unsigned long i2c_hash;	/* i2c devicelist hash - for boards with generic ID */
 
+	struct em28xx_audio *adev;
+
 	/* states */
 	enum em28xx_dev_state state;
 	enum em28xx_stream_state stream;
@@ -302,6 +326,15 @@ struct em28xx {
 struct em28xx_fh {
 	struct em28xx *dev;
 	unsigned int  stream_on:1;	/* Locks streams */
+	int           radio;
+};
+
+struct em28xx_ops {
+	struct list_head next;
+	char *name;
+	int id;
+	int (*init)(struct em28xx *);
+	int (*fini)(struct em28xx *);
 };
 
 /* Provided by em28xx-i2c.c */
@@ -341,6 +374,10 @@ int em28xx_init_isoc(struct em28xx *dev);
 void em28xx_uninit_isoc(struct em28xx *dev);
 int em28xx_set_alternate(struct em28xx *dev);
 
+/* Provided by em28xx-video.c */
+int em28xx_register_extension(struct em28xx_ops *dev);
+void em28xx_unregister_extension(struct em28xx_ops *dev);
+
 /* Provided by em28xx-cards.c */
 extern int em2800_variant_detect(struct usb_device* udev,int model);
 extern void em28xx_pre_card_setup(struct em28xx *dev);