openwrtv4/target/linux/brcm2708/patches-3.10/0007-bcm2708-alsa-sound-driver.patch

From f99826368eeb17ddaf6b9459f577356c0387f365 Mon Sep 17 00:00:00 2001
From: popcornmix <popcornmix@gmail.com>
Date: Mon, 26 Mar 2012 22:15:50 +0100
Subject: [PATCH 007/196] bcm2708: alsa sound driver

    Signed-off-by: popcornmix <popcornmix@gmail.com>
---
 arch/arm/configs/bcmrpi_cutdown_defconfig |  20 +
 arch/arm/configs/bcmrpi_defconfig         |  20 +
 arch/arm/mach-bcm2708/bcm2708.c           |  12 +
 sound/arm/Kconfig                         |   7 +
 sound/arm/Makefile                        |   6 +
 sound/arm/bcm2835-ctl.c                   | 200 +++++++
 sound/arm/bcm2835-pcm.c                   | 409 +++++++++++++++
 sound/arm/bcm2835-vchiq.c                 | 844 ++++++++++++++++++++++++++++++
 sound/arm/bcm2835.c                       | 413 +++++++++++++++
 sound/arm/bcm2835.h                       | 155 ++++++
 sound/arm/vc_vchi_audioserv_defs.h        | 116 ++++
 11 files changed, 2202 insertions(+)
 create mode 100755 sound/arm/bcm2835-ctl.c
 create mode 100755 sound/arm/bcm2835-pcm.c
 create mode 100755 sound/arm/bcm2835-vchiq.c
 create mode 100755 sound/arm/bcm2835.c
 create mode 100755 sound/arm/bcm2835.h
 create mode 100644 sound/arm/vc_vchi_audioserv_defs.h

diff --git a/arch/arm/configs/bcmrpi_cutdown_defconfig b/arch/arm/configs/bcmrpi_cutdown_defconfig
index 74f2dc9..e519412 100644
--- a/arch/arm/configs/bcmrpi_cutdown_defconfig
+++ b/arch/arm/configs/bcmrpi_cutdown_defconfig
@@ -208,6 +208,26 @@ CONFIG_FRAMEBUFFER_CONSOLE=y
 CONFIG_LOGO=y
 # CONFIG_LOGO_LINUX_MONO is not set
 # CONFIG_LOGO_LINUX_VGA16 is not set
+CONFIG_SOUND=y
+CONFIG_SND=m
+CONFIG_SND_SEQUENCER=m
+CONFIG_SND_SEQ_DUMMY=m
+CONFIG_SND_MIXER_OSS=m
+CONFIG_SND_PCM_OSS=m
+CONFIG_SND_SEQUENCER_OSS=y
+CONFIG_SND_HRTIMER=m
+CONFIG_SND_DUMMY=m
+CONFIG_SND_ALOOP=m
+CONFIG_SND_VIRMIDI=m
+CONFIG_SND_MTPAV=m
+CONFIG_SND_SERIAL_U16550=m
+CONFIG_SND_MPU401=m
+CONFIG_SND_BCM2835=m
+CONFIG_SND_USB_AUDIO=m
+CONFIG_SND_USB_UA101=m
+CONFIG_SND_USB_CAIAQ=m
+CONFIG_SND_USB_6FIRE=m
+CONFIG_SOUND_PRIME=m
 CONFIG_HID_PID=y
 CONFIG_USB_HIDDEV=y
 CONFIG_HID_A4TECH=m
diff --git a/arch/arm/configs/bcmrpi_defconfig b/arch/arm/configs/bcmrpi_defconfig
index 339aabf..df947e5 100644
--- a/arch/arm/configs/bcmrpi_defconfig
+++ b/arch/arm/configs/bcmrpi_defconfig
@@ -225,6 +225,26 @@ CONFIG_FRAMEBUFFER_CONSOLE=y
 CONFIG_LOGO=y
 # CONFIG_LOGO_LINUX_MONO is not set
 # CONFIG_LOGO_LINUX_VGA16 is not set
+CONFIG_SOUND=y
+CONFIG_SND=m
+CONFIG_SND_SEQUENCER=m
+CONFIG_SND_SEQ_DUMMY=m
+CONFIG_SND_MIXER_OSS=m
+CONFIG_SND_PCM_OSS=m
+CONFIG_SND_SEQUENCER_OSS=y
+CONFIG_SND_HRTIMER=m
+CONFIG_SND_DUMMY=m
+CONFIG_SND_ALOOP=m
+CONFIG_SND_VIRMIDI=m
+CONFIG_SND_MTPAV=m
+CONFIG_SND_SERIAL_U16550=m
+CONFIG_SND_MPU401=m
+CONFIG_SND_BCM2835=m
+CONFIG_SND_USB_AUDIO=m
+CONFIG_SND_USB_UA101=m
+CONFIG_SND_USB_CAIAQ=m
+CONFIG_SND_USB_6FIRE=m
+CONFIG_SOUND_PRIME=m
 CONFIG_HID_PID=y
 CONFIG_USB_HIDDEV=y
 CONFIG_HID_A4TECH=m
diff --git a/arch/arm/mach-bcm2708/bcm2708.c b/arch/arm/mach-bcm2708/bcm2708.c
index 64a2783..67f3608 100644
--- a/arch/arm/mach-bcm2708/bcm2708.c
+++ b/arch/arm/mach-bcm2708/bcm2708.c
@@ -424,6 +424,16 @@ struct platform_device bcm2708_powerman_device = {
 		.coherent_dma_mask = 0xffffffffUL},
 };
 
+
+static struct platform_device bcm2708_alsa_devices[] = {
+	[0] =	{
+		.name = "bcm2835_AUD0",
+		.id = 0,		/* first audio device */
+		.resource = 0,
+		.num_resources = 0,
+		},
+};
+
 int __init bcm_register_device(struct platform_device *pdev)
 {
 	int ret;
@@ -529,6 +539,8 @@ void __init bcm2708_init(void)
 	bcm_register_device(&bcm2708_emmc_device);
 #endif
 	bcm2708_init_led();
+	for (i = 0; i < ARRAY_SIZE(bcm2708_alsa_devices); i++)
+		bcm_register_device(&bcm2708_alsa_devices[i]);
 
 	for (i = 0; i < ARRAY_SIZE(amba_devs); i++) {
 		struct amba_device *d = amba_devs[i];
diff --git a/sound/arm/Kconfig b/sound/arm/Kconfig
index 885683a..f7ceafd 100644
--- a/sound/arm/Kconfig
+++ b/sound/arm/Kconfig
@@ -39,5 +39,12 @@ config SND_PXA2XX_AC97
 	  Say Y or M if you want to support any AC97 codec attached to
 	  the PXA2xx AC97 interface.
 
+config SND_BCM2835
+	tristate "BCM2835 ALSA driver"
+	depends on ARCH_BCM2708 && BCM2708_VCHIQ && SND
+	select SND_PCM
+	help
+	  Say Y or M if you want to support BCM2835 Alsa pcm card driver
+
 endif	# SND_ARM
 
diff --git a/sound/arm/Makefile b/sound/arm/Makefile
index 8c0c851..181cb57 100644
--- a/sound/arm/Makefile
+++ b/sound/arm/Makefile
@@ -14,3 +14,9 @@ snd-pxa2xx-lib-$(CONFIG_SND_PXA2XX_LIB_AC97)	+= pxa2xx-ac97-lib.o
 
 obj-$(CONFIG_SND_PXA2XX_AC97)	+= snd-pxa2xx-ac97.o
 snd-pxa2xx-ac97-objs		:= pxa2xx-ac97.o
+
+obj-$(CONFIG_SND_BCM2835)	+= snd-bcm2835.o
+snd-bcm2835-objs		:= bcm2835.o bcm2835-ctl.o bcm2835-pcm.o bcm2835-vchiq.o
+
+EXTRA_CFLAGS += -Idrivers/misc/vc04_services -Idrivers/misc/vc04_services/interface/vcos/linuxkernel -D__VCCOREVER__=0x04000000
+
diff --git a/sound/arm/bcm2835-ctl.c b/sound/arm/bcm2835-ctl.c
new file mode 100755
index 0000000..c3e0f7a
--- /dev/null
+++ b/sound/arm/bcm2835-ctl.c
@@ -0,0 +1,200 @@
+/*****************************************************************************
+* Copyright 2011 Broadcom Corporation.  All rights reserved.
+*
+* Unless you and Broadcom execute a separate written software license
+* agreement governing use of this software, this software is licensed to you
+* under the terms of the GNU General Public License version 2, available at
+* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
+*	
+* Notwithstanding the above, under no circumstances may you combine this
+* software in any way with any other Broadcom software provided under a
+* license other than the GPL, without Broadcom's express prior written
+* consent.
+*****************************************************************************/
+
+#include <linux/platform_device.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/jiffies.h>
+#include <linux/slab.h>
+#include <linux/time.h>
+#include <linux/wait.h>
+#include <linux/delay.h>
+#include <linux/moduleparam.h>
+#include <linux/sched.h>
+
+#include <sound/core.h>
+#include <sound/control.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/rawmidi.h>
+#include <sound/initval.h>
+#include <sound/tlv.h>
+
+#include "bcm2835.h"
+
+/* volume maximum and minimum in terms of 0.01dB */
+#define CTRL_VOL_MAX 400
+#define CTRL_VOL_MIN -10239 /* originally -10240 */
+
+
+static int snd_bcm2835_ctl_info(struct snd_kcontrol *kcontrol,
+				struct snd_ctl_elem_info *uinfo)
+{
+	audio_info(" ... IN\n");
+	if (kcontrol->private_value == PCM_PLAYBACK_VOLUME) {
+		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+		uinfo->count = 1;
+		uinfo->value.integer.min = CTRL_VOL_MIN;
+		uinfo->value.integer.max = CTRL_VOL_MAX;      /* 2303 */
+	} else if (kcontrol->private_value == PCM_PLAYBACK_MUTE) {
+		uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
+		uinfo->count = 1;
+		uinfo->value.integer.min = 0;
+		uinfo->value.integer.max = 1;
+	} else if (kcontrol->private_value == PCM_PLAYBACK_DEVICE) {
+		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+		uinfo->count = 1;
+		uinfo->value.integer.min = 0;
+		uinfo->value.integer.max = AUDIO_DEST_MAX-1;
+	}
+	audio_info(" ... OUT\n");
+	return 0;
+}
+
+/* toggles mute on or off depending on the value of nmute, and returns
+ * 1 if the mute value was changed, otherwise 0
+ */
+static int toggle_mute(struct bcm2835_chip *chip, int nmute)
+{
+	/* if settings are ok, just return 0 */
+	if(chip->mute == nmute)
+		return 0;
+
+	/* if the sound is muted then we need to unmute */
+	if(chip->mute == CTRL_VOL_MUTE)
+	{
+		chip->volume = chip->old_volume; /* copy the old volume back */
+		audio_info("Unmuting, old_volume = %d, volume = %d ...\n", chip->old_volume, chip->volume);
+	}
+	else /* otherwise we mute */
+	{
+		chip->old_volume = chip->volume;
+		chip->volume = 26214; /* set volume to minimum level AKA mute */
+		audio_info("Muting, old_volume = %d, volume = %d ...\n", chip->old_volume, chip->volume);
+	}
+
+	chip->mute = nmute;
+	return 1;
+}
+
+static int snd_bcm2835_ctl_get(struct snd_kcontrol *kcontrol,
+			       struct snd_ctl_elem_value *ucontrol)
+{
+	struct bcm2835_chip *chip = snd_kcontrol_chip(kcontrol);
+
+	BUG_ON(!chip && !(chip->avail_substreams & AVAIL_SUBSTREAMS_MASK));
+
+	if (kcontrol->private_value == PCM_PLAYBACK_VOLUME)
+		ucontrol->value.integer.value[0] = chip2alsa(chip->volume);
+	else if (kcontrol->private_value == PCM_PLAYBACK_MUTE)
+		ucontrol->value.integer.value[0] = chip->mute;
+	else if (kcontrol->private_value == PCM_PLAYBACK_DEVICE)
+		ucontrol->value.integer.value[0] = chip->dest;
+
+	return 0;
+}
+
+static int snd_bcm2835_ctl_put(struct snd_kcontrol *kcontrol,
+			       struct snd_ctl_elem_value *ucontrol)
+{
+	struct bcm2835_chip *chip = snd_kcontrol_chip(kcontrol);
+	int changed = 0;
+
+	if (kcontrol->private_value == PCM_PLAYBACK_VOLUME) {
+		audio_info("Volume change attempted.. volume = %d new_volume = %d\n", chip->volume, (int)ucontrol->value.integer.value[0]);
+		if (chip->mute == CTRL_VOL_MUTE) {
+			/* changed = toggle_mute(chip, CTRL_VOL_UNMUTE); */
+			return 1; /* should return 0 to signify no change but the mixer takes this as the opposite sign (no idea why) */
+		}
+		if (changed
+		    || (ucontrol->value.integer.value[0] != chip2alsa(chip->volume))) {
+
+			chip->volume = alsa2chip(ucontrol->value.integer.value[0]);
+			changed = 1;
+		}
+
+	} else if (kcontrol->private_value == PCM_PLAYBACK_MUTE) {
+		/* Now implemented */
+		audio_info(" Mute attempted\n");
+		changed = toggle_mute(chip, ucontrol->value.integer.value[0]);
+
+	} else if (kcontrol->private_value == PCM_PLAYBACK_DEVICE) {
+		if (ucontrol->value.integer.value[0] != chip->dest) {
+			chip->dest = ucontrol->value.integer.value[0];
+			changed = 1;
+		}
+	}
+
+	if (changed) {
+		if (bcm2835_audio_set_ctls(chip))
+			printk(KERN_ERR "Failed to set ALSA controls..\n");
+	}
+
+	return changed;
+}
+
+static DECLARE_TLV_DB_SCALE(snd_bcm2835_db_scale, CTRL_VOL_MIN, 1, 1);
+
+static struct snd_kcontrol_new snd_bcm2835_ctl[] = {
+	{
+	 .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+	 .name = "PCM Playback Volume",
+	 .index = 0,
+	 .access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ,
+	 .private_value = PCM_PLAYBACK_VOLUME,
+	 .info = snd_bcm2835_ctl_info,
+	 .get = snd_bcm2835_ctl_get,
+	 .put = snd_bcm2835_ctl_put,
+	 .count = 1,
+	 .tlv = {.p = snd_bcm2835_db_scale}
+	},
+	{
+	 .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+	 .name = "PCM Playback Switch",
+	 .index = 0,
+	 .access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
+	 .private_value = PCM_PLAYBACK_MUTE,
+	 .info = snd_bcm2835_ctl_info,
+	 .get = snd_bcm2835_ctl_get,
+	 .put = snd_bcm2835_ctl_put,
+	 .count = 1,
+	 },
+	{
+	 .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+	 .name = "PCM Playback Route",
+	 .index = 0,
+	 .access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
+	 .private_value = PCM_PLAYBACK_DEVICE,
+	 .info = snd_bcm2835_ctl_info,
+	 .get = snd_bcm2835_ctl_get,
+	 .put = snd_bcm2835_ctl_put,
+	 .count = 1,
+	},
+};
+
+int snd_bcm2835_new_ctl(bcm2835_chip_t * chip)
+{
+	int err;
+	unsigned int idx;
+
+	strcpy(chip->card->mixername, "Broadcom Mixer");
+	for (idx = 0; idx < ARRAY_SIZE(snd_bcm2835_ctl); idx++) {
+		err =
+		    snd_ctl_add(chip->card,
+				snd_ctl_new1(&snd_bcm2835_ctl[idx], chip));
+		if (err < 0)
+			return err;
+	}
+	return 0;
+}
diff --git a/sound/arm/bcm2835-pcm.c b/sound/arm/bcm2835-pcm.c
new file mode 100755
index 0000000..4206b7e
--- /dev/null
+++ b/sound/arm/bcm2835-pcm.c
@@ -0,0 +1,409 @@
+/*****************************************************************************
+* Copyright 2011 Broadcom Corporation.  All rights reserved.
+*
+* Unless you and Broadcom execute a separate written software license
+* agreement governing use of this software, this software is licensed to you
+* under the terms of the GNU General Public License version 2, available at
+* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
+*	
+* Notwithstanding the above, under no circumstances may you combine this
+* software in any way with any other Broadcom software provided under a
+* license other than the GPL, without Broadcom's express prior written
+* consent.
+*****************************************************************************/
+
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+
+#include "bcm2835.h"
+
+/* hardware definition */
+static struct snd_pcm_hardware snd_bcm2835_playback_hw = {
+	.info = (SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER),
+	.formats = SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE,
+	.rates = SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000,
+	.rate_min = 8000,
+	.rate_max = 48000,
+	.channels_min = 1,
+	.channels_max = 2,
+	.buffer_bytes_max = 128 * 1024,
+	.period_bytes_min =   1 * 1024,
+	.period_bytes_max = 128 * 1024,
+	.periods_min = 1,
+	.periods_max = 128,
+};
+
+static void snd_bcm2835_playback_free(struct snd_pcm_runtime *runtime)
+{
+	audio_info("Freeing up alsa stream here ..\n");
+	if (runtime->private_data)
+		kfree(runtime->private_data);
+	runtime->private_data = NULL;
+}
+
+static irqreturn_t bcm2835_playback_fifo_irq(int irq, void *dev_id)
+{
+	bcm2835_alsa_stream_t *alsa_stream = (bcm2835_alsa_stream_t *) dev_id;
+	uint32_t consumed = 0;
+	int new_period = 0;
+
+	audio_info(" .. IN\n");
+
+	audio_info("alsa_stream=%p substream=%p\n", alsa_stream,
+		   alsa_stream ? alsa_stream->substream : 0);
+
+	if (alsa_stream->open)
+		consumed = bcm2835_audio_retrieve_buffers(alsa_stream);
+
+	/* We get called only if playback was triggered, So, the number of buffers we retrieve in
+	 * each iteration are the buffers that have been played out already
+	 */
+
+	if (alsa_stream->period_size) {
+		if ((alsa_stream->pos / alsa_stream->period_size) !=
+		    ((alsa_stream->pos + consumed) / alsa_stream->period_size))
+			new_period = 1;
+	}
+	audio_debug("updating pos cur: %d + %d max:%d period_bytes:%d, hw_ptr: %d new_period:%d\n",
+		      alsa_stream->pos,
+		      consumed,
+		      alsa_stream->buffer_size,
+			  (int)(alsa_stream->period_size*alsa_stream->substream->runtime->periods),
+			  frames_to_bytes(alsa_stream->substream->runtime, alsa_stream->substream->runtime->status->hw_ptr),
+			  new_period);
+	if (alsa_stream->buffer_size) {
+		alsa_stream->pos += consumed &~ (1<<30);
+		alsa_stream->pos %= alsa_stream->buffer_size;
+	}
+
+	if (alsa_stream->substream) {
+		if (new_period)
+			snd_pcm_period_elapsed(alsa_stream->substream);
+	} else {
+		audio_warning(" unexpected NULL substream\n");
+	}
+	audio_info(" .. OUT\n");
+
+	return IRQ_HANDLED;
+}
+
+/* open callback */
+static int snd_bcm2835_playback_open(struct snd_pcm_substream *substream)
+{
+	bcm2835_chip_t *chip = snd_pcm_substream_chip(substream);
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	bcm2835_alsa_stream_t *alsa_stream;
+	int idx;
+	int err;
+
+	audio_info(" .. IN (%d)\n", substream->number);
+
+	audio_info("Alsa open (%d)\n", substream->number);
+	idx = substream->number;
+
+	if (idx > MAX_SUBSTREAMS) {
+		audio_error
+		    ("substream(%d) device doesn't exist max(%d) substreams allowed\n",
+		     idx, MAX_SUBSTREAMS);
+		err = -ENODEV;
+		goto out;
+	}
+
+	/* Check if we are ready */
+	if (!(chip->avail_substreams & (1 << idx))) {
+		/* We are not ready yet */
+		audio_error("substream(%d) device is not ready yet\n", idx);
+		err = -EAGAIN;
+		goto out;
+	}
+
+	alsa_stream = kzalloc(sizeof(bcm2835_alsa_stream_t), GFP_KERNEL);
+	if (alsa_stream == NULL) {
+		return -ENOMEM;
+	}
+
+	/* Initialise alsa_stream */
+	alsa_stream->chip = chip;
+	alsa_stream->substream = substream;
+	alsa_stream->idx = idx;
+	chip->alsa_stream[idx] = alsa_stream;
+
+	sema_init(&alsa_stream->buffers_update_sem, 0);
+	sema_init(&alsa_stream->control_sem, 0);
+	spin_lock_init(&alsa_stream->lock);
+
+	/* Enabled in start trigger, called on each "fifo irq" after that */
+	alsa_stream->enable_fifo_irq = 0;
+	alsa_stream->fifo_irq_handler = bcm2835_playback_fifo_irq;
+
+	runtime->private_data = alsa_stream;
+	runtime->private_free = snd_bcm2835_playback_free;
+	runtime->hw = snd_bcm2835_playback_hw;
+	/* minimum 16 bytes alignment (for vchiq bulk transfers) */
+	snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
+				   16);
+
+	err = bcm2835_audio_open(alsa_stream);
+	if (err != 0) {
+		kfree(alsa_stream);
+		return err;
+	}
+
+	alsa_stream->open = 1;
+	alsa_stream->draining = 1;
+
+out:
+	audio_info(" .. OUT =%d\n", err);
+
+	return err;
+}
+
+/* close callback */
+static int snd_bcm2835_playback_close(struct snd_pcm_substream *substream)
+{
+	/* the hardware-specific codes will be here */
+
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	bcm2835_alsa_stream_t *alsa_stream = runtime->private_data;
+
+	audio_info(" .. IN\n");
+	audio_info("Alsa close\n");
+
+	/*
+	 * Call stop if it's still running. This happens when app
+	 * is force killed and we don't get a stop trigger.
+	 */
+	if (alsa_stream->running) {
+		int err;
+		err = bcm2835_audio_stop(alsa_stream);
+		alsa_stream->running = 0;
+		if (err != 0)
+			audio_error(" Failed to STOP alsa device\n");
+	}
+
+	alsa_stream->period_size = 0;
+	alsa_stream->buffer_size = 0;
+
+	if (alsa_stream->open) {
+		alsa_stream->open = 0;
+		bcm2835_audio_close(alsa_stream);
+	}
+	if (alsa_stream->chip)
+		alsa_stream->chip->alsa_stream[alsa_stream->idx] = NULL;
+	/*
+	 * Do not free up alsa_stream here, it will be freed up by
+	 * runtime->private_free callback we registered in *_open above
+	 */
+
+	audio_info(" .. OUT\n");
+
+	return 0;
+}
+
+/* hw_params callback */
+static int snd_bcm2835_pcm_hw_params(struct snd_pcm_substream *substream,
+				     struct snd_pcm_hw_params *params)
+{
+	int err;
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	bcm2835_alsa_stream_t *alsa_stream =
+	    (bcm2835_alsa_stream_t *) runtime->private_data;
+
+	audio_info(" .. IN\n");
+
+	err = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
+	if (err < 0) {
+		audio_error
+		    (" pcm_lib_malloc failed to allocated pages for buffers\n");
+		return err;
+	}
+
+	err = bcm2835_audio_set_params(alsa_stream, params_channels(params),
+				       params_rate(params),
+				       snd_pcm_format_width(params_format
+							    (params)));
+	if (err < 0) {
+		audio_error(" error setting hw params\n");
+	}
+
+	bcm2835_audio_setup(alsa_stream);
+
+	/* in preparation of the stream, set the controls (volume level) of the stream */
+	bcm2835_audio_set_ctls(alsa_stream->chip);
+
+	audio_info(" .. OUT\n");
+
+	return err;
+}
+
+/* hw_free callback */
+static int snd_bcm2835_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+	audio_info(" .. IN\n");
+	return snd_pcm_lib_free_pages(substream);
+}
+
+/* prepare callback */
+static int snd_bcm2835_pcm_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	bcm2835_alsa_stream_t *alsa_stream = runtime->private_data;
+
+	audio_info(" .. IN\n");
+
+	alsa_stream->buffer_size = snd_pcm_lib_buffer_bytes(substream);
+	alsa_stream->period_size = snd_pcm_lib_period_bytes(substream);
+	alsa_stream->pos = 0;
+
+	audio_debug("buffer_size=%d, period_size=%d pos=%d frame_bits=%d\n",
+		      alsa_stream->buffer_size, alsa_stream->period_size,
+		      alsa_stream->pos, runtime->frame_bits);
+
+	audio_info(" .. OUT\n");
+	return 0;
+}
+
+/* trigger callback */
+static int snd_bcm2835_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	bcm2835_alsa_stream_t *alsa_stream = runtime->private_data;
+	int err = 0;
+
+	audio_info(" .. IN\n");
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		audio_debug("bcm2835_AUDIO_TRIGGER_START running=%d\n",
+			      alsa_stream->running);
+		if (!alsa_stream->running) {
+			err = bcm2835_audio_start(alsa_stream);
+			if (err == 0) {
+				alsa_stream->running = 1;
+				alsa_stream->draining = 1;
+			} else {
+				audio_error(" Failed to START alsa device (%d)\n", err);
+			}
+		}
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+		audio_debug
+		    ("bcm2835_AUDIO_TRIGGER_STOP running=%d draining=%d\n",
+			     alsa_stream->running, runtime->status->state == SNDRV_PCM_STATE_DRAINING);
+		if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
+			audio_info("DRAINING\n");
+			alsa_stream->draining = 1;
+		} else {
+			audio_info("DROPPING\n");
+			alsa_stream->draining = 0;
+		}
+		if (alsa_stream->running) {
+			err = bcm2835_audio_stop(alsa_stream);
+			if (err != 0)
+				audio_error(" Failed to STOP alsa device (%d)\n", err);
+			alsa_stream->running = 0;
+		}
+		break;
+	default:
+		err = -EINVAL;
+	}
+
+	audio_info(" .. OUT\n");
+	return err;
+}
+
+/* pointer callback */
+static snd_pcm_uframes_t
+snd_bcm2835_pcm_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	bcm2835_alsa_stream_t *alsa_stream = runtime->private_data;
+
+	audio_info(" .. IN\n");
+
+	audio_debug("pcm_pointer... (%d) hwptr=%d appl=%d pos=%d\n", 0,
+		      frames_to_bytes(runtime, runtime->status->hw_ptr),
+		      frames_to_bytes(runtime, runtime->control->appl_ptr),
+		      alsa_stream->pos);
+
+	audio_info(" .. OUT\n");
+	return bytes_to_frames(runtime, alsa_stream->pos);
+}
+
+static int snd_bcm2835_pcm_copy(struct snd_pcm_substream *substream,
+				int channel, snd_pcm_uframes_t pos, void *src,
+				snd_pcm_uframes_t count)
+{
+	int ret;
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	bcm2835_alsa_stream_t *alsa_stream = runtime->private_data;
+
+	audio_info(" .. IN\n");
+	audio_debug("copy.......... (%d) hwptr=%d appl=%d pos=%d\n",
+		      frames_to_bytes(runtime, count), frames_to_bytes(runtime,
+								       runtime->
+								       status->
+								       hw_ptr),
+		      frames_to_bytes(runtime, runtime->control->appl_ptr),
+		      alsa_stream->pos);
+	ret =
+	    bcm2835_audio_write(alsa_stream, frames_to_bytes(runtime, count),
+				src);
+	audio_info(" .. OUT\n");
+	return ret;
+}
+
+static int snd_bcm2835_pcm_lib_ioctl(struct snd_pcm_substream *substream,
+				     unsigned int cmd, void *arg)
+{
+	int ret = snd_pcm_lib_ioctl(substream, cmd, arg);
+	audio_info(" .. substream=%p, cmd=%d, arg=%p (%x) ret=%d\n", substream,
+		    cmd, arg, arg ? *(unsigned *)arg : 0, ret);
+	return ret;
+}
+
+/* operators */
+static struct snd_pcm_ops snd_bcm2835_playback_ops = {
+	.open = snd_bcm2835_playback_open,
+	.close = snd_bcm2835_playback_close,
+	.ioctl = snd_bcm2835_pcm_lib_ioctl,
+	.hw_params = snd_bcm2835_pcm_hw_params,
+	.hw_free = snd_bcm2835_pcm_hw_free,
+	.prepare = snd_bcm2835_pcm_prepare,
+	.trigger = snd_bcm2835_pcm_trigger,
+	.pointer = snd_bcm2835_pcm_pointer,
+	.copy = snd_bcm2835_pcm_copy,
+};
+
+/* create a pcm device */
+int snd_bcm2835_new_pcm(bcm2835_chip_t * chip)
+{
+	struct snd_pcm *pcm;
+	int err;
+
+	audio_info(" .. IN\n");
+	err =
+	    snd_pcm_new(chip->card, "bcm2835 ALSA", 0, MAX_SUBSTREAMS, 0, &pcm);
+	if (err < 0)
+		return err;
+	pcm->private_data = chip;
+	strcpy(pcm->name, "bcm2835 ALSA");
+	chip->pcm = pcm;
+	chip->dest = AUDIO_DEST_AUTO;
+	chip->volume = alsa2chip(0);
+	chip->mute = CTRL_VOL_UNMUTE;	/*disable mute on startup */
+	/* set operators */
+	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
+			&snd_bcm2835_playback_ops);
+
+	/* pre-allocation of buffers */
+	/* NOTE: this may fail */
+	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
+					      snd_dma_continuous_data
+					      (GFP_KERNEL), 64 * 1024,
+					      64 * 1024);
+
+	audio_info(" .. OUT\n");
+
+	return 0;
+}
diff --git a/sound/arm/bcm2835-vchiq.c b/sound/arm/bcm2835-vchiq.c
new file mode 100755
index 0000000..9ecb2d6
--- /dev/null
+++ b/sound/arm/bcm2835-vchiq.c
@@ -0,0 +1,844 @@
+/*****************************************************************************
+* Copyright 2011 Broadcom Corporation.  All rights reserved.
+*
+* Unless you and Broadcom execute a separate written software license
+* agreement governing use of this software, this software is licensed to you
+* under the terms of the GNU General Public License version 2, available at
+* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
+*	
+* Notwithstanding the above, under no circumstances may you combine this
+* software in any way with any other Broadcom software provided under a
+* license other than the GPL, without Broadcom's express prior written
+* consent.
+*****************************************************************************/
+
+#include <linux/device.h>
+#include <sound/core.h>
+#include <sound/initval.h>
+#include <sound/pcm.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/mm.h>
+#include <linux/syscalls.h>
+#include <asm/uaccess.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/atomic.h>
+#include <linux/module.h>
+
+#include "bcm2835.h"
+
+/* ---- Include Files -------------------------------------------------------- */
+
+#include "interface/vchi/vchi.h"
+#include "vc_vchi_audioserv_defs.h"
+
+/* ---- Private Constants and Types ------------------------------------------ */
+
+/* Logging macros (for remapping to other logging mechanisms, i.e., printf) */
+#ifdef AUDIO_DEBUG_ENABLE
+	#define LOG_ERR( fmt, arg... )   pr_err( "%s:%d " fmt, __func__, __LINE__, ##arg)
+	#define LOG_WARN( fmt, arg... )  pr_info( "%s:%d " fmt, __func__, __LINE__, ##arg)
+	#define LOG_INFO( fmt, arg... )  pr_info( "%s:%d " fmt, __func__, __LINE__, ##arg)
+	#define LOG_DBG( fmt, arg... )   pr_info( "%s:%d " fmt, __func__, __LINE__, ##arg)
+#else
+	#define LOG_ERR( fmt, arg... )   pr_err( "%s:%d " fmt, __func__, __LINE__, ##arg)
+	#define LOG_WARN( fmt, arg... )
+	#define LOG_INFO( fmt, arg... )
+	#define LOG_DBG( fmt, arg... )
+#endif
+
+typedef struct opaque_AUDIO_INSTANCE_T {
+	uint32_t num_connections;
+	VCHI_SERVICE_HANDLE_T vchi_handle[VCHI_MAX_NUM_CONNECTIONS];
+	struct semaphore msg_avail_event;
+	struct mutex vchi_mutex;
+	bcm2835_alsa_stream_t *alsa_stream;
+	int32_t result;
+	short peer_version;
+} AUDIO_INSTANCE_T;
+
+bool force_bulk = false;
+
+/* ---- Private Variables ---------------------------------------------------- */
+
+/* ---- Private Function Prototypes ------------------------------------------ */
+
+/* ---- Private Functions ---------------------------------------------------- */
+
+static int bcm2835_audio_stop_worker(bcm2835_alsa_stream_t * alsa_stream);
+static int bcm2835_audio_start_worker(bcm2835_alsa_stream_t * alsa_stream);
+
+typedef struct {
+	struct work_struct my_work;
+	bcm2835_alsa_stream_t *alsa_stream;
+	int x;
+} my_work_t;
+
+static void my_wq_function(struct work_struct *work)
+{
+	my_work_t *w = (my_work_t *) work;
+	int ret = -9;
+	LOG_DBG(" .. IN %p:%d\n", w->alsa_stream, w->x);
+	switch (w->x) {
+	case 1:
+		ret = bcm2835_audio_start_worker(w->alsa_stream);
+		break;
+	case 2:
+		ret = bcm2835_audio_stop_worker(w->alsa_stream);
+		break;
+	default:
+		LOG_ERR(" Unexpected work: %p:%d\n", w->alsa_stream, w->x);
+		break;
+	}
+	kfree((void *)work);
+	LOG_DBG(" .. OUT %d\n", ret);
+}
+
+int bcm2835_audio_start(bcm2835_alsa_stream_t * alsa_stream)
+{
+	int ret = -1;
+	LOG_DBG(" .. IN\n");
+	if (alsa_stream->my_wq) {
+		my_work_t *work = kmalloc(sizeof(my_work_t), GFP_ATOMIC);
+		/*--- Queue some work (item 1) ---*/
+		if (work) {
+			INIT_WORK((struct work_struct *)work, my_wq_function);
+			work->alsa_stream = alsa_stream;
+			work->x = 1;
+			if (queue_work
+			    (alsa_stream->my_wq, (struct work_struct *)work))
+				ret = 0;
+		} else
+			LOG_ERR(" .. Error: NULL work kmalloc\n");
+	}
+	LOG_DBG(" .. OUT %d\n", ret);
+	return ret;
+}
+
+int bcm2835_audio_stop(bcm2835_alsa_stream_t * alsa_stream)
+{
+	int ret = -1;
+	LOG_DBG(" .. IN\n");
+	if (alsa_stream->my_wq) {
+		my_work_t *work = kmalloc(sizeof(my_work_t), GFP_ATOMIC);
+		 /*--- Queue some work (item 1) ---*/
+		if (work) {
+			INIT_WORK((struct work_struct *)work, my_wq_function);
+			work->alsa_stream = alsa_stream;
+			work->x = 2;
+			if (queue_work
+			    (alsa_stream->my_wq, (struct work_struct *)work))
+				ret = 0;
+		} else
+			LOG_ERR(" .. Error: NULL work kmalloc\n");
+	}
+	LOG_DBG(" .. OUT %d\n", ret);
+	return ret;
+}
+
+void my_workqueue_init(bcm2835_alsa_stream_t * alsa_stream)
+{
+	alsa_stream->my_wq = create_workqueue("my_queue");
+	return;
+}
+
+void my_workqueue_quit(bcm2835_alsa_stream_t * alsa_stream)
+{
+	if (alsa_stream->my_wq) {
+		flush_workqueue(alsa_stream->my_wq);
+		destroy_workqueue(alsa_stream->my_wq);
+		alsa_stream->my_wq = NULL;
+	}
+	return;
+}
+
+static void audio_vchi_callback(void *param,
+				const VCHI_CALLBACK_REASON_T reason,
+				void *msg_handle)
+{
+	AUDIO_INSTANCE_T *instance = (AUDIO_INSTANCE_T *) param;
+	int32_t status;
+	int32_t msg_len;
+	VC_AUDIO_MSG_T m;
+	bcm2835_alsa_stream_t *alsa_stream = 0;
+	LOG_DBG(" .. IN instance=%p, param=%p, reason=%d, handle=%p\n",
+		instance, param, reason, msg_handle);
+
+	if (!instance || reason != VCHI_CALLBACK_MSG_AVAILABLE) {
+		return;
+	}
+	alsa_stream = instance->alsa_stream;
+	status = vchi_msg_dequeue(instance->vchi_handle[0],
+				  &m, sizeof m, &msg_len, VCHI_FLAGS_NONE);
+	if (m.type == VC_AUDIO_MSG_TYPE_RESULT) {
+		LOG_DBG
+		    (" .. instance=%p, m.type=VC_AUDIO_MSG_TYPE_RESULT, success=%d\n",
+		     instance, m.u.result.success);
+		instance->result = m.u.result.success;
+		up(&instance->msg_avail_event);
+	} else if (m.type == VC_AUDIO_MSG_TYPE_COMPLETE) {
+		irq_handler_t callback = (irq_handler_t) m.u.complete.callback;
+		LOG_DBG
+		    (" .. instance=%p, m.type=VC_AUDIO_MSG_TYPE_COMPLETE, complete=%d\n",
+		     instance, m.u.complete.count);
+		if (alsa_stream && callback) {
+			atomic_add(m.u.complete.count, &alsa_stream->retrieved);
+			callback(0, alsa_stream);
+		} else {
+			LOG_DBG(" .. unexpected alsa_stream=%p, callback=%p\n",
+				alsa_stream, callback);
+		}
+	} else {
+		LOG_DBG(" .. unexpected m.type=%d\n", m.type);
+	}
+	LOG_DBG(" .. OUT\n");
+}
+
+static AUDIO_INSTANCE_T *vc_vchi_audio_init(VCHI_INSTANCE_T vchi_instance,
+					    VCHI_CONNECTION_T **
+					    vchi_connections,
+					    uint32_t num_connections)
+{
+	uint32_t i;
+	AUDIO_INSTANCE_T *instance;
+	int status;
+
+	LOG_DBG("%s: start", __func__);
+
+	if (num_connections > VCHI_MAX_NUM_CONNECTIONS) {
+		LOG_ERR("%s: unsupported number of connections %u (max=%u)\n",
+			__func__, num_connections, VCHI_MAX_NUM_CONNECTIONS);
+
+		return NULL;
+	}
+	/* Allocate memory for this instance */
+	instance = kmalloc(sizeof(*instance), GFP_KERNEL);
+
+	memset(instance, 0, sizeof(*instance));
+	instance->num_connections = num_connections;
+
+	/* Create a lock for exclusive, serialized VCHI connection access */
+	mutex_init(&instance->vchi_mutex);
+	/* Open the VCHI service connections */
+	for (i = 0; i < num_connections; i++) {
+		SERVICE_CREATION_T params = {
+			VCHI_VERSION_EX(VC_AUDIOSERV_VER, VC_AUDIOSERV_MIN_VER),
+			VC_AUDIO_SERVER_NAME,	// 4cc service code
+			vchi_connections[i],	// passed in fn pointers
+			0,	// rx fifo size (unused)
+			0,	// tx fifo size (unused)
+			audio_vchi_callback,	// service callback
+			instance,	// service callback parameter
+			1,	//TODO: remove VCOS_FALSE,   // unaligned bulk recieves
+			1,	//TODO: remove VCOS_FALSE,   // unaligned bulk transmits
+			0	// want crc check on bulk transfers
+		};
+
+		status = vchi_service_open(vchi_instance, &params,
+					   &instance->vchi_handle[i]);
+		if (status) {
+			LOG_ERR
+			    ("%s: failed to open VCHI service connection (status=%d)\n",
+			     __func__, status);
+
+			goto err_close_services;
+		}
+		/* Finished with the service for now */
+		vchi_service_release(instance->vchi_handle[i]);
+	}
+
+	return instance;
+
+err_close_services:
+	for (i = 0; i < instance->num_connections; i++) {
+		vchi_service_close(instance->vchi_handle[i]);
+	}
+
+	kfree(instance);
+
+	return NULL;
+}
+
+static int32_t vc_vchi_audio_deinit(AUDIO_INSTANCE_T * instance)
+{
+	uint32_t i;
+
+	LOG_DBG(" .. IN\n");
+
+	if (instance == NULL) {
+		LOG_ERR("%s: invalid handle %p\n", __func__, instance);
+
+		return -1;
+	}
+
+	LOG_DBG(" .. about to lock (%d)\n", instance->num_connections);
+	if(mutex_lock_interruptible(&instance->vchi_mutex))
+	{
+		LOG_DBG("Interrupted whilst waiting for lock on (%d)\n",instance->num_connections);
+		return -EINTR;
+	}
+
+	/* Close all VCHI service connections */
+	for (i = 0; i < instance->num_connections; i++) {
+		int32_t success;
+		LOG_DBG(" .. %i:closing %p\n", i, instance->vchi_handle[i]);
+		vchi_service_use(instance->vchi_handle[i]);
+
+		success = vchi_service_close(instance->vchi_handle[i]);
+		if (success != 0) {
+			LOG_ERR
+			    ("%s: failed to close VCHI service connection (status=%d)\n",
+			     __func__, success);
+		}
+	}
+
+	mutex_unlock(&instance->vchi_mutex);
+
+	kfree(instance);
+
+	LOG_DBG(" .. OUT\n");
+
+	return 0;
+}
+
+static int bcm2835_audio_open_connection(bcm2835_alsa_stream_t * alsa_stream)
+{
+	static VCHI_INSTANCE_T vchi_instance;
+	static VCHI_CONNECTION_T *vchi_connection;
+	AUDIO_INSTANCE_T *instance = alsa_stream->instance;
+	int ret;
+	LOG_DBG(" .. IN\n");
+
+	LOG_INFO("%s: start", __func__);
+	//BUG_ON(instance);
+	if (instance) {
+		LOG_ERR("%s: VCHI instance already open (%p)\n",
+			__func__, instance);
+		instance->alsa_stream = alsa_stream;
+		alsa_stream->instance = instance;
+		ret = 0;	// xxx todo -1;
+		goto err_free_mem;
+	}
+
+	/* Initialize and create a VCHI connection */
+	ret = vchi_initialise(&vchi_instance);
+	if (ret != 0) {
+		LOG_ERR("%s: failed to initialise VCHI instance (ret=%d)\n",
+			__func__, ret);
+
+		ret = -EIO;
+		goto err_free_mem;
+	}
+	ret = vchi_connect(NULL, 0, vchi_instance);
+	if (ret != 0) {
+		LOG_ERR("%s: failed to connect VCHI instance (ret=%d)\n",
+			__func__, ret);
+
+		ret = -EIO;
+		goto err_free_mem;
+	}
+
+	/* Initialize an instance of the audio service */
+	instance = vc_vchi_audio_init(vchi_instance, &vchi_connection, 1);
+
+	if (instance == NULL /*|| audio_handle != instance */ ) {
+		LOG_ERR("%s: failed to initialize audio service\n", __func__);
+
+		ret = -EPERM;
+		goto err_free_mem;
+	}
+
+	instance->alsa_stream = alsa_stream;
+	alsa_stream->instance = instance;
+
+	LOG_DBG(" success !\n");
+err_free_mem:
+	LOG_DBG(" .. OUT\n");
+
+	return ret;
+}
+
+int bcm2835_audio_open(bcm2835_alsa_stream_t * alsa_stream)
+{
+	AUDIO_INSTANCE_T *instance;
+	VC_AUDIO_MSG_T m;
+	int32_t success;
+	int ret;
+	LOG_DBG(" .. IN\n");
+
+	my_workqueue_init(alsa_stream);
+
+	ret = bcm2835_audio_open_connection(alsa_stream);
+	if (ret != 0) {
+		ret = -1;
+		goto exit;
+	}
+	instance = alsa_stream->instance;
+
+	if(mutex_lock_interruptible(&instance->vchi_mutex))
+	{
+		LOG_DBG("Interrupted whilst waiting for lock on (%d)\n",instance->num_connections);
+		return -EINTR;
+	}
+	vchi_service_use(instance->vchi_handle[0]);
+
+	m.type = VC_AUDIO_MSG_TYPE_OPEN;
+
+	/* Send the message to the videocore */
+	success = vchi_msg_queue(instance->vchi_handle[0],
+				 &m, sizeof m,
+				 VCHI_FLAGS_BLOCK_UNTIL_QUEUED, NULL);
+
+	if (success != 0) {
+		LOG_ERR("%s: failed on vchi_msg_queue (status=%d)\n",
+			__func__, success);
+
+		ret = -1;
+		goto unlock;
+	}
+
+	ret = 0;
+
+unlock:
+	vchi_service_release(instance->vchi_handle[0]);
+	mutex_unlock(&instance->vchi_mutex);
+exit:
+	LOG_DBG(" .. OUT\n");
+	return ret;
+}
+
+static int bcm2835_audio_set_ctls_chan(bcm2835_alsa_stream_t * alsa_stream,
+				       bcm2835_chip_t * chip)
+{
+	VC_AUDIO_MSG_T m;
+	AUDIO_INSTANCE_T *instance = alsa_stream->instance;
+	int32_t success;
+	int ret;
+	LOG_DBG(" .. IN\n");
+
+	LOG_INFO
+	    (" Setting ALSA dest(%d), volume(%d)\n", chip->dest, chip->volume);
+
+	if(mutex_lock_interruptible(&instance->vchi_mutex))
+	{
+		LOG_DBG("Interrupted whilst waiting for lock on (%d)\n",instance->num_connections);
+		return -EINTR;
+	}
+	vchi_service_use(instance->vchi_handle[0]);
+
+	instance->result = -1;
+
+	m.type = VC_AUDIO_MSG_TYPE_CONTROL;
+	m.u.control.dest = chip->dest;
+	m.u.control.volume = chip->volume;
+
+	/* Create the message available event */
+	sema_init(&instance->msg_avail_event, 0);
+
+	/* Send the message to the videocore */
+	success = vchi_msg_queue(instance->vchi_handle[0],
+				 &m, sizeof m,
+				 VCHI_FLAGS_BLOCK_UNTIL_QUEUED, NULL);
+
+	if (success != 0) {
+		LOG_ERR("%s: failed on vchi_msg_queue (status=%d)\n",
+			__func__, success);
+
+		ret = -1;
+		goto unlock;
+	}
+
+	/* We are expecting a reply from the videocore */
+	if (down_interruptible(&instance->msg_avail_event)) {
+		LOG_ERR("%s: failed on waiting for event (status=%d)\n",
+			__func__, success);
+
+		ret = -1;
+		goto unlock;
+	}
+
+	if (instance->result != 0) {
+		LOG_ERR("%s: result=%d\n", __func__, instance->result);
+
+		ret = -1;
+		goto unlock;
+	}
+
+	ret = 0;
+
+unlock:
+	vchi_service_release(instance->vchi_handle[0]);
+	mutex_unlock(&instance->vchi_mutex);
+
+	LOG_DBG(" .. OUT\n");
+	return ret;
+}
+
+int bcm2835_audio_set_ctls(bcm2835_chip_t * chip)
+{
+	int i;
+	int ret = 0;
+	LOG_DBG(" .. IN\n");
+
+	/* change ctls for all substreams */
+	for (i = 0; i < MAX_SUBSTREAMS; i++) {
+		if (chip->avail_substreams & (1 << i)) {
+			if (!chip->alsa_stream[i])
+			{
+				LOG_DBG(" No ALSA stream available?! %i:%p (%x)\n", i, chip->alsa_stream[i], chip->avail_substreams);
+				ret = 0;
+			}
+			else if (bcm2835_audio_set_ctls_chan /* returns 0 on success */
+				 (chip->alsa_stream[i], chip) != 0)
+				 {
+					LOG_DBG("Couldn't set the controls for stream %d\n", i);
+					ret = -1;
+				 }
+			else LOG_DBG(" Controls set for stream %d\n", i);
+		}
+	}
+	LOG_DBG(" .. OUT ret=%d\n", ret);
+	return ret;
+}
+
+int bcm2835_audio_set_params(bcm2835_alsa_stream_t * alsa_stream,
+			     uint32_t channels, uint32_t samplerate,
+			     uint32_t bps)
+{
+	VC_AUDIO_MSG_T m;
+	AUDIO_INSTANCE_T *instance = alsa_stream->instance;
+	int32_t success;
+	int ret;
+	LOG_DBG(" .. IN\n");
+
+	LOG_INFO
+	    (" Setting ALSA channels(%d), samplerate(%d), bits-per-sample(%d)\n",
+	     channels, samplerate, bps);
+
+	/* resend ctls - alsa_stream may not have been open when first send */
+	ret = bcm2835_audio_set_ctls_chan(alsa_stream, alsa_stream->chip);
+	if (ret != 0) {
+		LOG_ERR(" Alsa controls not supported\n");
+		return -EINVAL;
+	}
+
+	if(mutex_lock_interruptible(&instance->vchi_mutex))
+	{
+		LOG_DBG("Interrupted whilst waiting for lock on (%d)\n",instance->num_connections);
+		return -EINTR;
+	}
+	vchi_service_use(instance->vchi_handle[0]);
+
+	instance->result = -1;
+
+	m.type = VC_AUDIO_MSG_TYPE_CONFIG;
+	m.u.config.channels = channels;
+	m.u.config.samplerate = samplerate;
+	m.u.config.bps = bps;
+
+	/* Create the message available event */
+	sema_init(&instance->msg_avail_event, 0);
+
+	/* Send the message to the videocore */
+	success = vchi_msg_queue(instance->vchi_handle[0],
+				 &m, sizeof m,
+				 VCHI_FLAGS_BLOCK_UNTIL_QUEUED, NULL);
+
+	if (success != 0) {
+		LOG_ERR("%s: failed on vchi_msg_queue (status=%d)\n",
+			__func__, success);
+
+		ret = -1;
+		goto unlock;
+	}
+
+	/* We are expecting a reply from the videocore */
+	if (down_interruptible(&instance->msg_avail_event)) {
+		LOG_ERR("%s: failed on waiting for event (status=%d)\n",
+			__func__, success);
+
+		ret = -1;
+		goto unlock;
+	}
+
+	if (instance->result != 0) {
+		LOG_ERR("%s: result=%d", __func__, instance->result);
+
+		ret = -1;
+		goto unlock;
+	}
+
+	ret = 0;
+
+unlock:
+	vchi_service_release(instance->vchi_handle[0]);
+	mutex_unlock(&instance->vchi_mutex);
+
+	LOG_DBG(" .. OUT\n");
+	return ret;
+}
+
+int bcm2835_audio_setup(bcm2835_alsa_stream_t * alsa_stream)
+{
+	LOG_DBG(" .. IN\n");
+
+	LOG_DBG(" .. OUT\n");
+
+	return 0;
+}
+
+static int bcm2835_audio_start_worker(bcm2835_alsa_stream_t * alsa_stream)
+{
+	VC_AUDIO_MSG_T m;
+	AUDIO_INSTANCE_T *instance = alsa_stream->instance;
+	int32_t success;
+	int ret;
+	LOG_DBG(" .. IN\n");
+
+	if(mutex_lock_interruptible(&instance->vchi_mutex))
+	{
+		LOG_DBG("Interrupted whilst waiting for lock on (%d)\n",instance->num_connections);
+		return -EINTR;
+	}
+	vchi_service_use(instance->vchi_handle[0]);
+
+	m.type = VC_AUDIO_MSG_TYPE_START;
+
+	/* Send the message to the videocore */
+	success = vchi_msg_queue(instance->vchi_handle[0],
+				 &m, sizeof m,
+				 VCHI_FLAGS_BLOCK_UNTIL_QUEUED, NULL);
+
+	if (success != 0) {
+		LOG_ERR("%s: failed on vchi_msg_queue (status=%d)",
+			__func__, success);
+
+		ret = -1;
+		goto unlock;
+	}
+
+	ret = 0;
+
+unlock:
+	vchi_service_release(instance->vchi_handle[0]);
+	mutex_unlock(&instance->vchi_mutex);
+	LOG_DBG(" .. OUT\n");
+	return ret;
+}
+
+static int bcm2835_audio_stop_worker(bcm2835_alsa_stream_t * alsa_stream)
+{
+	VC_AUDIO_MSG_T m;
+	AUDIO_INSTANCE_T *instance = alsa_stream->instance;
+	int32_t success;
+	int ret;
+	LOG_DBG(" .. IN\n");
+
+	if(mutex_lock_interruptible(&instance->vchi_mutex))
+	{
+		LOG_DBG("Interrupted whilst waiting for lock on (%d)\n",instance->num_connections);
+		return -EINTR;
+	}
+	vchi_service_use(instance->vchi_handle[0]);
+
+	m.type = VC_AUDIO_MSG_TYPE_STOP;
+	m.u.stop.draining = alsa_stream->draining;
+
+	/* Send the message to the videocore */
+	success = vchi_msg_queue(instance->vchi_handle[0],
+				 &m, sizeof m,
+				 VCHI_FLAGS_BLOCK_UNTIL_QUEUED, NULL);
+
+	if (success != 0) {
+		LOG_ERR("%s: failed on vchi_msg_queue (status=%d)",
+			__func__, success);
+
+		ret = -1;
+		goto unlock;
+	}
+
+	ret = 0;
+
+unlock:
+	vchi_service_release(instance->vchi_handle[0]);
+	mutex_unlock(&instance->vchi_mutex);
+	LOG_DBG(" .. OUT\n");
+	return ret;
+}
+
+int bcm2835_audio_close(bcm2835_alsa_stream_t * alsa_stream)
+{
+	VC_AUDIO_MSG_T m;
+	AUDIO_INSTANCE_T *instance = alsa_stream->instance;
+	int32_t success;
+	int ret;
+	LOG_DBG(" .. IN\n");
+
+	my_workqueue_quit(alsa_stream);
+
+	if(mutex_lock_interruptible(&instance->vchi_mutex))
+	{
+		LOG_DBG("Interrupted whilst waiting for lock on (%d)\n",instance->num_connections);
+		return -EINTR;
+	}
+	vchi_service_use(instance->vchi_handle[0]);
+
+	m.type = VC_AUDIO_MSG_TYPE_CLOSE;
+
+	/* Create the message available event */
+	sema_init(&instance->msg_avail_event, 0);
+
+	/* Send the message to the videocore */
+	success = vchi_msg_queue(instance->vchi_handle[0],
+				 &m, sizeof m,
+				 VCHI_FLAGS_BLOCK_UNTIL_QUEUED, NULL);
+
+	if (success != 0) {
+		LOG_ERR("%s: failed on vchi_msg_queue (status=%d)",
+			__func__, success);
+		ret = -1;
+		goto unlock;
+	}
+	if (down_interruptible(&instance->msg_avail_event)) {
+		LOG_ERR("%s: failed on waiting for event (status=%d)",
+			__func__, success);
+
+		ret = -1;
+		goto unlock;
+	}
+	if (instance->result != 0) {
+		LOG_ERR("%s: failed result (status=%d)",
+			__func__, instance->result);
+
+		ret = -1;
+		goto unlock;
+	}
+
+	ret = 0;
+
+unlock:
+	vchi_service_release(instance->vchi_handle[0]);
+	mutex_unlock(&instance->vchi_mutex);
+
+	/* Stop the audio service */
+	if (instance) {
+		vc_vchi_audio_deinit(instance);
+		alsa_stream->instance = NULL;
+	}
+	LOG_DBG(" .. OUT\n");
+	return ret;
+}
+
+int bcm2835_audio_write(bcm2835_alsa_stream_t * alsa_stream, uint32_t count,
+			void *src)
+{
+	VC_AUDIO_MSG_T m;
+	AUDIO_INSTANCE_T *instance = alsa_stream->instance;
+	int32_t success;
+	int ret;
+
+	LOG_DBG(" .. IN\n");
+
+	LOG_INFO(" Writing %d bytes from %p\n", count, src);
+
+	if(mutex_lock_interruptible(&instance->vchi_mutex))
+	{
+		LOG_DBG("Interrupted whilst waiting for lock on (%d)\n",instance->num_connections);
+		return -EINTR;
+	}
+	vchi_service_use(instance->vchi_handle[0]);
+
+	if ( instance->peer_version==0 && vchi_get_peer_version(instance->vchi_handle[0], &instance->peer_version) == 0 ) {
+		LOG_DBG("%s: client version %d connected\n", __func__, instance->peer_version);
+	}
+	m.type = VC_AUDIO_MSG_TYPE_WRITE;
+	m.u.write.count = count;
+	// old version uses bulk, new version uses control
+	m.u.write.max_packet = instance->peer_version < 2 || force_bulk ? 0:4000;
+	m.u.write.callback = alsa_stream->fifo_irq_handler;
+	m.u.write.cookie = alsa_stream;
+	m.u.write.silence = src == NULL;
+
+	/* Send the message to the videocore */
+	success = vchi_msg_queue(instance->vchi_handle[0],
+				 &m, sizeof m,
+				 VCHI_FLAGS_BLOCK_UNTIL_QUEUED, NULL);
+
+	if (success != 0) {
+		LOG_ERR("%s: failed on vchi_msg_queue (status=%d)",
+			__func__, success);
+
+		ret = -1;
+		goto unlock;
+	}
+	if (!m.u.write.silence) {
+		if (m.u.write.max_packet == 0) {
+			/* Send the message to the videocore */
+			success = vchi_bulk_queue_transmit(instance->vchi_handle[0],
+							   src, count,
+							   0 *
+							   VCHI_FLAGS_BLOCK_UNTIL_QUEUED
+							   +
+							   1 *
+							   VCHI_FLAGS_BLOCK_UNTIL_DATA_READ,
+							   NULL);
+		} else {
+			while (count > 0) {
+				int bytes = min((int)m.u.write.max_packet, (int)count);
+				success = vchi_msg_queue(instance->vchi_handle[0],
+							 src, bytes,
+							 VCHI_FLAGS_BLOCK_UNTIL_QUEUED, NULL);
+				src = (char *)src + bytes;
+				count -= bytes;
+			}
+		}
+		if (success != 0) {
+			LOG_ERR
+			    ("%s: failed on vchi_bulk_queue_transmit (status=%d)",
+			     __func__, success);
+
+			ret = -1;
+			goto unlock;
+		}
+	}
+	ret = 0;
+
+unlock:
+	vchi_service_release(instance->vchi_handle[0]);
+	mutex_unlock(&instance->vchi_mutex);
+	LOG_DBG(" .. OUT\n");
+	return ret;
+}
+
+/**
+  * Returns all buffers from arm->vc
+  */
+void bcm2835_audio_flush_buffers(bcm2835_alsa_stream_t * alsa_stream)
+{
+	LOG_DBG(" .. IN\n");
+	LOG_DBG(" .. OUT\n");
+	return;
+}
+
+/**
+  * Forces VC to flush(drop) its filled playback buffers and 
+  * return them the us. (VC->ARM)
+  */
+void bcm2835_audio_flush_playback_buffers(bcm2835_alsa_stream_t * alsa_stream)
+{
+	LOG_DBG(" .. IN\n");
+	LOG_DBG(" .. OUT\n");
+}
+
+uint32_t bcm2835_audio_retrieve_buffers(bcm2835_alsa_stream_t * alsa_stream)
+{
+	uint32_t count = atomic_read(&alsa_stream->retrieved);
+	atomic_sub(count, &alsa_stream->retrieved);
+	return count;
+}
+
+module_param(force_bulk, bool, 0444);
+MODULE_PARM_DESC(force_bulk, "Force use of vchiq bulk for audio");
diff --git a/sound/arm/bcm2835.c b/sound/arm/bcm2835.c
new file mode 100755
index 0000000..e5ac894
--- /dev/null
+++ b/sound/arm/bcm2835.c
@@ -0,0 +1,413 @@
+/*****************************************************************************
+* Copyright 2011 Broadcom Corporation.  All rights reserved.
+*
+* Unless you and Broadcom execute a separate written software license
+* agreement governing use of this software, this software is licensed to you
+* under the terms of the GNU General Public License version 2, available at
+* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
+*	
+* Notwithstanding the above, under no circumstances may you combine this
+* software in any way with any other Broadcom software provided under a
+* license other than the GPL, without Broadcom's express prior written
+* consent.
+*****************************************************************************/
+
+#include <linux/platform_device.h>
+
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+#include "bcm2835.h"
+
+/* module parameters (see "Module Parameters") */
+/* SNDRV_CARDS: maximum number of cards supported by this module */
+static int index[MAX_SUBSTREAMS] = {[0 ... (MAX_SUBSTREAMS - 1)] = -1 };
+static char *id[MAX_SUBSTREAMS] = {[0 ... (MAX_SUBSTREAMS - 1)] = NULL };
+static int enable[MAX_SUBSTREAMS] = {[0 ... (MAX_SUBSTREAMS - 1)] = 1 };
+
+/* HACKY global pointers needed for successive probes to work : ssp
+ * But compared against the changes we will have to do in VC audio_ipc code
+ * to export 8 audio_ipc devices as a single IPC device and then monitor all
+ * four devices in a thread, this gets things done quickly and should be easier
+ * to debug if we run into issues
+ */
+
+static struct snd_card *g_card = NULL;
+static bcm2835_chip_t *g_chip = NULL;
+
+static int snd_bcm2835_free(bcm2835_chip_t * chip)
+{
+	kfree(chip);
+	return 0;
+}
+
+/* component-destructor
+ * (see "Management of Cards and Components")
+ */
+static int snd_bcm2835_dev_free(struct snd_device *device)
+{
+	return snd_bcm2835_free(device->device_data);
+}
+
+/* chip-specific constructor
+ * (see "Management of Cards and Components")
+ */
+static int snd_bcm2835_create(struct snd_card *card,
+					struct platform_device *pdev,
+					bcm2835_chip_t ** rchip)
+{
+	bcm2835_chip_t *chip;
+	int err;
+	static struct snd_device_ops ops = {
+		.dev_free = snd_bcm2835_dev_free,
+	};
+
+	*rchip = NULL;
+
+	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+	if (chip == NULL)
+		return -ENOMEM;
+
+	chip->card = card;
+
+	err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops);
+	if (err < 0) {
+		snd_bcm2835_free(chip);
+		return err;
+	}
+
+	*rchip = chip;
+	return 0;
+}
+
+static int snd_bcm2835_alsa_probe(struct platform_device *pdev)
+{
+	static int dev;
+	bcm2835_chip_t *chip;
+	struct snd_card *card;
+	int err;
+
+	if (dev >= MAX_SUBSTREAMS)
+		return -ENODEV;
+
+	if (!enable[dev]) {
+		dev++;
+		return -ENOENT;
+	}
+
+	if (dev > 0)
+		goto add_register_map;
+
+	err = snd_card_create(index[dev], id[dev], THIS_MODULE, 0, &g_card);
+	if (err < 0)
+		goto out;
+
+	snd_card_set_dev(g_card, &pdev->dev);
+	strcpy(g_card->driver, "BRCM bcm2835 ALSA Driver");
+	strcpy(g_card->shortname, "bcm2835 ALSA");
+	sprintf(g_card->longname, "%s", g_card->shortname);
+
+	err = snd_bcm2835_create(g_card, pdev, &chip);
+	if (err < 0) {
+		printk(KERN_ERR "Failed to create bcm2835 chip\n");
+		goto out_bcm2835_create;
+	}
+
+	g_chip = chip;
+	err = snd_bcm2835_new_pcm(chip);
+	if (err < 0) {
+		printk(KERN_ERR "Failed to create new BCM2835 pcm device\n");
+		goto out_bcm2835_new_pcm;
+	}
+
+	err = snd_bcm2835_new_ctl(chip);
+	if (err < 0) {
+		printk(KERN_ERR "Failed to create new BCM2835 ctl\n");
+		goto out_bcm2835_new_ctl;
+	}
+
+add_register_map:
+	card = g_card;
+	chip = g_chip;
+
+	BUG_ON(!(card && chip));
+
+	chip->avail_substreams |= (1 << dev);
+	chip->pdev[dev] = pdev;
+
+	if (dev == 0) {
+		err = snd_card_register(card);
+		if (err < 0) {
+			printk(KERN_ERR
+			       "Failed to register bcm2835 ALSA card \n");
+			goto out_card_register;
+		}
+		platform_set_drvdata(pdev, card);
+		printk(KERN_INFO "bcm2835 ALSA card created!\n");
+	} else {
+		printk(KERN_INFO "bcm2835 ALSA chip created!\n");
+		platform_set_drvdata(pdev, (void *)dev);
+	}
+
+	dev++;
+
+	return 0;
+
+out_card_register:
+out_bcm2835_new_ctl:
+out_bcm2835_new_pcm:
+out_bcm2835_create:
+	BUG_ON(!g_card);
+	if (snd_card_free(g_card))
+		printk(KERN_ERR "Failed to free Registered alsa card\n");
+	g_card = NULL;
+out:
+	dev = SNDRV_CARDS;	/* stop more avail_substreams from being probed */
+	printk(KERN_ERR "BCM2835 ALSA Probe failed !!\n");
+	return err;
+}
+
+static int snd_bcm2835_alsa_remove(struct platform_device *pdev)
+{
+	uint32_t idx;
+	void *drv_data;
+
+	drv_data = platform_get_drvdata(pdev);
+
+	if (drv_data == (void *)g_card) {
+		/* This is the card device */
+		snd_card_free((struct snd_card *)drv_data);
+		g_card = NULL;
+		g_chip = NULL;
+	} else {
+		idx = (uint32_t) drv_data;
+		if (g_card != NULL) {
+			BUG_ON(!g_chip);
+			/* We pass chip device numbers in audio ipc devices
+			 * other than the one we registered our card with
+			 */
+			idx = (uint32_t) drv_data;
+			BUG_ON(!idx || idx > MAX_SUBSTREAMS);
+			g_chip->avail_substreams &= ~(1 << idx);
+			/* There should be atleast one substream registered
+			 * after we are done here, as it wil be removed when
+			 * the *remove* is called for the card device
+			 */
+			BUG_ON(!g_chip->avail_substreams);
+		}
+	}
+
+	platform_set_drvdata(pdev, NULL);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int snd_bcm2835_alsa_suspend(struct platform_device *pdev,
+				    pm_message_t state)
+{
+	return 0;
+}
+
+static int snd_bcm2835_alsa_resume(struct platform_device *pdev)
+{
+	return 0;
+}
+
+#endif
+
+static struct platform_driver bcm2835_alsa0_driver = {
+	.probe = snd_bcm2835_alsa_probe,
+	.remove = snd_bcm2835_alsa_remove,
+#ifdef CONFIG_PM
+	.suspend = snd_bcm2835_alsa_suspend,
+	.resume = snd_bcm2835_alsa_resume,
+#endif
+	.driver = {
+		   .name = "bcm2835_AUD0",
+		   .owner = THIS_MODULE,
+		   },
+};
+
+static struct platform_driver bcm2835_alsa1_driver = {
+	.probe = snd_bcm2835_alsa_probe,
+	.remove = snd_bcm2835_alsa_remove,
+#ifdef CONFIG_PM
+	.suspend = snd_bcm2835_alsa_suspend,
+	.resume = snd_bcm2835_alsa_resume,
+#endif
+	.driver = {
+		   .name = "bcm2835_AUD1",
+		   .owner = THIS_MODULE,
+		   },
+};
+
+static struct platform_driver bcm2835_alsa2_driver = {
+	.probe = snd_bcm2835_alsa_probe,
+	.remove = snd_bcm2835_alsa_remove,
+#ifdef CONFIG_PM
+	.suspend = snd_bcm2835_alsa_suspend,
+	.resume = snd_bcm2835_alsa_resume,
+#endif
+	.driver = {
+		   .name = "bcm2835_AUD2",
+		   .owner = THIS_MODULE,
+		   },
+};
+
+static struct platform_driver bcm2835_alsa3_driver = {
+	.probe = snd_bcm2835_alsa_probe,
+	.remove = snd_bcm2835_alsa_remove,
+#ifdef CONFIG_PM
+	.suspend = snd_bcm2835_alsa_suspend,
+	.resume = snd_bcm2835_alsa_resume,
+#endif
+	.driver = {
+		   .name = "bcm2835_AUD3",
+		   .owner = THIS_MODULE,
+		   },
+};
+
+static struct platform_driver bcm2835_alsa4_driver = {
+	.probe = snd_bcm2835_alsa_probe,
+	.remove = snd_bcm2835_alsa_remove,
+#ifdef CONFIG_PM
+	.suspend = snd_bcm2835_alsa_suspend,
+	.resume = snd_bcm2835_alsa_resume,
+#endif
+	.driver = {
+		   .name = "bcm2835_AUD4",
+		   .owner = THIS_MODULE,
+		   },
+};
+
+static struct platform_driver bcm2835_alsa5_driver = {
+	.probe = snd_bcm2835_alsa_probe,
+	.remove = snd_bcm2835_alsa_remove,
+#ifdef CONFIG_PM
+	.suspend = snd_bcm2835_alsa_suspend,
+	.resume = snd_bcm2835_alsa_resume,
+#endif
+	.driver = {
+		   .name = "bcm2835_AUD5",
+		   .owner = THIS_MODULE,
+		   },
+};
+
+static struct platform_driver bcm2835_alsa6_driver = {
+	.probe = snd_bcm2835_alsa_probe,
+	.remove = snd_bcm2835_alsa_remove,
+#ifdef CONFIG_PM
+	.suspend = snd_bcm2835_alsa_suspend,
+	.resume = snd_bcm2835_alsa_resume,
+#endif
+	.driver = {
+		   .name = "bcm2835_AUD6",
+		   .owner = THIS_MODULE,
+		   },
+};
+
+static struct platform_driver bcm2835_alsa7_driver = {
+	.probe = snd_bcm2835_alsa_probe,
+	.remove = snd_bcm2835_alsa_remove,
+#ifdef CONFIG_PM
+	.suspend = snd_bcm2835_alsa_suspend,
+	.resume = snd_bcm2835_alsa_resume,
+#endif
+	.driver = {
+		   .name = "bcm2835_AUD7",
+		   .owner = THIS_MODULE,
+		   },
+};
+
+static int bcm2835_alsa_device_init(void)
+{
+	int err;
+	err = platform_driver_register(&bcm2835_alsa0_driver);
+	if (err) {
+		printk("Error registering bcm2835_alsa0_driver %d .\n", err);
+		goto out;
+	}
+
+	err = platform_driver_register(&bcm2835_alsa1_driver);
+	if (err) {
+		printk("Error registering bcm2835_alsa1_driver %d .\n", err);
+		goto unregister_0;
+	}
+
+	err = platform_driver_register(&bcm2835_alsa2_driver);
+	if (err) {
+		printk("Error registering bcm2835_alsa2_driver %d .\n", err);
+		goto unregister_1;
+	}
+
+	err = platform_driver_register(&bcm2835_alsa3_driver);
+	if (err) {
+		printk("Error registering bcm2835_alsa3_driver %d .\n", err);
+		goto unregister_2;
+	}
+
+	err = platform_driver_register(&bcm2835_alsa4_driver);
+	if (err) {
+		printk("Error registering bcm2835_alsa4_driver %d .\n", err);
+		goto unregister_3;
+	}
+
+	err = platform_driver_register(&bcm2835_alsa5_driver);
+	if (err) {
+		printk("Error registering bcm2835_alsa5_driver %d .\n", err);
+		goto unregister_4;
+	}
+
+	err = platform_driver_register(&bcm2835_alsa6_driver);
+	if (err) {
+		printk("Error registering bcm2835_alsa6_driver %d .\n", err);
+		goto unregister_5;
+	}
+
+	err = platform_driver_register(&bcm2835_alsa7_driver);
+	if (err) {
+		printk("Error registering bcm2835_alsa7_driver %d .\n", err);
+		goto unregister_6;
+	}
+
+	return 0;
+
+unregister_6:
+	platform_driver_unregister(&bcm2835_alsa6_driver);
+unregister_5:
+	platform_driver_unregister(&bcm2835_alsa5_driver);
+unregister_4:
+	platform_driver_unregister(&bcm2835_alsa4_driver);
+unregister_3:
+	platform_driver_unregister(&bcm2835_alsa3_driver);
+unregister_2:
+	platform_driver_unregister(&bcm2835_alsa2_driver);
+unregister_1:
+	platform_driver_unregister(&bcm2835_alsa1_driver);
+unregister_0:
+	platform_driver_unregister(&bcm2835_alsa0_driver);
+out:
+	return err;
+}
+
+static void bcm2835_alsa_device_exit(void)
+{
+	platform_driver_unregister(&bcm2835_alsa0_driver);
+	platform_driver_unregister(&bcm2835_alsa1_driver);
+	platform_driver_unregister(&bcm2835_alsa2_driver);
+	platform_driver_unregister(&bcm2835_alsa3_driver);
+	platform_driver_unregister(&bcm2835_alsa4_driver);
+	platform_driver_unregister(&bcm2835_alsa5_driver);
+	platform_driver_unregister(&bcm2835_alsa6_driver);
+	platform_driver_unregister(&bcm2835_alsa7_driver);
+}
+
+late_initcall(bcm2835_alsa_device_init);
+module_exit(bcm2835_alsa_device_exit);
+
+MODULE_AUTHOR("Dom Cobley");
+MODULE_DESCRIPTION("Alsa driver for BCM2835 chip");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:bcm2835_alsa");
diff --git a/sound/arm/bcm2835.h b/sound/arm/bcm2835.h
new file mode 100755
index 0000000..b966e28
--- /dev/null
+++ b/sound/arm/bcm2835.h
@@ -0,0 +1,155 @@
+/*****************************************************************************
+* Copyright 2011 Broadcom Corporation.  All rights reserved.
+*
+* Unless you and Broadcom execute a separate written software license
+* agreement governing use of this software, this software is licensed to you
+* under the terms of the GNU General Public License version 2, available at
+* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
+*	
+* Notwithstanding the above, under no circumstances may you combine this
+* software in any way with any other Broadcom software provided under a
+* license other than the GPL, without Broadcom's express prior written
+* consent.
+*****************************************************************************/
+
+#ifndef __SOUND_ARM_BCM2835_H
+#define __SOUND_ARM_BCM2835_H
+
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/interrupt.h>
+#include <linux/wait.h>
+#include <sound/core.h>
+#include <sound/initval.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <linux/workqueue.h>
+
+/*
+#define AUDIO_DEBUG_ENABLE
+#define AUDIO_VERBOSE_DEBUG_ENABLE
+*/
+
+/* Debug macros */
+
+#ifdef AUDIO_DEBUG_ENABLE
+#ifdef AUDIO_VERBOSE_DEBUG_ENABLE
+
+#define audio_debug(fmt, arg...)	\
+	printk(KERN_INFO"%s:%d " fmt, __func__, __LINE__, ##arg)
+
+#define audio_info(fmt, arg...)	\
+	printk(KERN_INFO"%s:%d " fmt, __func__, __LINE__, ##arg)
+
+#else
+
+#define audio_debug(fmt, arg...)
+
+#define audio_info(fmt, arg...)
+
+#endif /* AUDIO_VERBOSE_DEBUG_ENABLE */
+
+#else
+
+#define audio_debug(fmt, arg...)
+
+#define audio_info(fmt, arg...)
+
+#endif /* AUDIO_DEBUG_ENABLE */
+
+#define audio_error(fmt, arg...)	\
+	printk(KERN_ERR"%s:%d " fmt, __func__, __LINE__, ##arg)
+
+#define audio_warning(fmt, arg...)	\
+	printk(KERN_WARNING"%s:%d " fmt, __func__, __LINE__, ##arg)
+
+#define audio_alert(fmt, arg...)	\
+	printk(KERN_ALERT"%s:%d " fmt, __func__, __LINE__, ##arg)
+
+#define MAX_SUBSTREAMS			(8)
+#define AVAIL_SUBSTREAMS_MASK		(0xff)
+enum {
+	CTRL_VOL_MUTE,
+	CTRL_VOL_UNMUTE
+};
+
+/* macros for alsa2chip and chip2alsa, instead of functions */
+
+#define alsa2chip(vol) (uint)(-((vol << 8) / 100))	/* convert alsa to chip volume (defined as macro rather than function call) */
+#define chip2alsa(vol) -((vol * 100) >> 8)			/* convert chip to alsa volume */
+
+/* Some constants for values .. */
+typedef enum {
+	AUDIO_DEST_AUTO = 0,
+	AUDIO_DEST_HEADPHONES = 1,
+	AUDIO_DEST_HDMI = 2,
+	AUDIO_DEST_MAX,
+} SND_BCM2835_ROUTE_T;
+
+typedef enum {
+	PCM_PLAYBACK_VOLUME,
+	PCM_PLAYBACK_MUTE,
+	PCM_PLAYBACK_DEVICE,
+} SND_BCM2835_CTRL_T;
+
+/* definition of the chip-specific record */
+typedef struct bcm2835_chip {
+	struct snd_card *card;
+	struct snd_pcm *pcm;
+	/* Bitmat for valid reg_base and irq numbers */
+	uint32_t avail_substreams;
+	struct platform_device *pdev[MAX_SUBSTREAMS];
+	struct bcm2835_alsa_stream *alsa_stream[MAX_SUBSTREAMS];
+
+	int volume;
+	int old_volume; /* stores the volume value whist muted */
+	int dest;
+	int mute;
+} bcm2835_chip_t;
+
+typedef struct bcm2835_alsa_stream {
+	bcm2835_chip_t *chip;
+	struct snd_pcm_substream *substream;
+
+	struct semaphore buffers_update_sem;
+	struct semaphore control_sem;
+	spinlock_t lock;
+	volatile uint32_t control;
+	volatile uint32_t status;
+
+	int open;
+	int running;
+	int draining;
+
+	unsigned int pos;
+	unsigned int buffer_size;
+	unsigned int period_size;
+
+	uint32_t enable_fifo_irq;
+	irq_handler_t fifo_irq_handler;
+
+	atomic_t retrieved;
+	struct opaque_AUDIO_INSTANCE_T *instance;
+	struct workqueue_struct *my_wq;
+	int idx;
+} bcm2835_alsa_stream_t;
+
+int snd_bcm2835_new_ctl(bcm2835_chip_t * chip);
+int snd_bcm2835_new_pcm(bcm2835_chip_t * chip);
+
+int bcm2835_audio_open(bcm2835_alsa_stream_t * alsa_stream);
+int bcm2835_audio_close(bcm2835_alsa_stream_t * alsa_stream);
+int bcm2835_audio_set_params(bcm2835_alsa_stream_t * alsa_stream,
+			     uint32_t channels, uint32_t samplerate,
+			     uint32_t bps);
+int bcm2835_audio_setup(bcm2835_alsa_stream_t * alsa_stream);
+int bcm2835_audio_start(bcm2835_alsa_stream_t * alsa_stream);
+int bcm2835_audio_stop(bcm2835_alsa_stream_t * alsa_stream);
+int bcm2835_audio_set_ctls(bcm2835_chip_t * chip);
+int bcm2835_audio_write(bcm2835_alsa_stream_t * alsa_stream, uint32_t count,
+			void *src);
+uint32_t bcm2835_audio_retrieve_buffers(bcm2835_alsa_stream_t * alsa_stream);
+void bcm2835_audio_flush_buffers(bcm2835_alsa_stream_t * alsa_stream);
+void bcm2835_audio_flush_playback_buffers(bcm2835_alsa_stream_t * alsa_stream);
+
+#endif /* __SOUND_ARM_BCM2835_H */
diff --git a/sound/arm/vc_vchi_audioserv_defs.h b/sound/arm/vc_vchi_audioserv_defs.h
new file mode 100644
index 0000000..af3e6eb
--- /dev/null
+++ b/sound/arm/vc_vchi_audioserv_defs.h
@@ -0,0 +1,116 @@
+/*****************************************************************************
+* Copyright 2011 Broadcom Corporation.  All rights reserved.
+*
+* Unless you and Broadcom execute a separate written software license
+* agreement governing use of this software, this software is licensed to you
+* under the terms of the GNU General Public License version 2, available at
+* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
+*
+* Notwithstanding the above, under no circumstances may you combine this
+* software in any way with any other Broadcom software provided under a
+* license other than the GPL, without Broadcom's express prior written
+* consent.
+*****************************************************************************/
+
+#ifndef _VC_AUDIO_DEFS_H_
+#define _VC_AUDIO_DEFS_H_
+
+#define VC_AUDIOSERV_MIN_VER 1
+#define VC_AUDIOSERV_VER 2
+
+// FourCC code used for VCHI connection
+#define VC_AUDIO_SERVER_NAME  MAKE_FOURCC("AUDS")
+
+// Maximum message length
+#define VC_AUDIO_MAX_MSG_LEN  (sizeof( VC_AUDIO_MSG_T ))
+
+// List of screens that are currently supported
+// All message types supported for HOST->VC direction
+typedef enum {
+	VC_AUDIO_MSG_TYPE_RESULT,	// Generic result
+	VC_AUDIO_MSG_TYPE_COMPLETE,	// Generic result
+	VC_AUDIO_MSG_TYPE_CONFIG,	// Configure audio
+	VC_AUDIO_MSG_TYPE_CONTROL,	// Configure audio
+	VC_AUDIO_MSG_TYPE_OPEN,	// Configure audio
+	VC_AUDIO_MSG_TYPE_CLOSE,	// Configure audio
+	VC_AUDIO_MSG_TYPE_START,	// Configure audio
+	VC_AUDIO_MSG_TYPE_STOP,	// Configure audio
+	VC_AUDIO_MSG_TYPE_WRITE,	// Configure audio
+	VC_AUDIO_MSG_TYPE_MAX
+} VC_AUDIO_MSG_TYPE;
+
+// configure the audio
+typedef struct {
+	uint32_t channels;
+	uint32_t samplerate;
+	uint32_t bps;
+
+} VC_AUDIO_CONFIG_T;
+
+typedef struct {
+	uint32_t volume;
+	uint32_t dest;
+
+} VC_AUDIO_CONTROL_T;
+
+// audio
+typedef struct {
+	uint32_t dummy;
+
+} VC_AUDIO_OPEN_T;
+
+// audio
+typedef struct {
+	uint32_t dummy;
+
+} VC_AUDIO_CLOSE_T;
+// audio
+typedef struct {
+	uint32_t dummy;
+
+} VC_AUDIO_START_T;
+// audio
+typedef struct {
+	uint32_t draining;
+
+} VC_AUDIO_STOP_T;
+
+// configure the write audio samples
+typedef struct {
+	uint32_t count;		// in bytes
+	void *callback;
+	void *cookie;
+	uint16_t silence;
+	uint16_t max_packet;
+} VC_AUDIO_WRITE_T;
+
+// Generic result for a request (VC->HOST)
+typedef struct {
+	int32_t success;	// Success value
+
+} VC_AUDIO_RESULT_T;
+
+// Generic result for a request (VC->HOST)
+typedef struct {
+	int32_t count;		// Success value
+	void *callback;
+	void *cookie;
+} VC_AUDIO_COMPLETE_T;
+
+// Message header for all messages in HOST->VC direction
+typedef struct {
+	int32_t type;		// Message type (VC_AUDIO_MSG_TYPE)
+	union {
+		VC_AUDIO_CONFIG_T config;
+		VC_AUDIO_CONTROL_T control;
+		VC_AUDIO_OPEN_T open;
+		VC_AUDIO_CLOSE_T close;
+		VC_AUDIO_START_T start;
+		VC_AUDIO_STOP_T stop;
+		VC_AUDIO_WRITE_T write;
+		VC_AUDIO_RESULT_T result;
+		VC_AUDIO_COMPLETE_T complete;
+	} u;
+} VC_AUDIO_MSG_T;
+
+#endif // _VC_AUDIO_DEFS_H_
-- 
1.9.1