ASoC: Add drivers for the Texas Instruments OMAP processors

Add common OMAP ASoC drivers and machine driver for Nokia N810. Currently
supported features are:

- Covers OMAPs from 1510 to 2420
- Common DMA driver
- DAI link driver using McBSP port in I2S mode
- Basic machine driver for Nokia N810
Signed-off-by: Jarkko Nikula <jarkko.nikula@nokia.com>

sound/soc/Kconfig

@@ -29,6 +29,7 @@ source "sound/soc/pxa/Kconfig"
 source "sound/soc/s3c24xx/Kconfig"
 source "sound/soc/sh/Kconfig"
 source "sound/soc/fsl/Kconfig"
+source "sound/soc/omap/Kconfig"
 
 # Supported codecs
 source "sound/soc/codecs/Kconfig"

sound/soc/Makefile

 snd-soc-core-objs := soc-core.o soc-dapm.o
 
 obj-$(CONFIG_SND_SOC)	+= snd-soc-core.o
-obj-$(CONFIG_SND_SOC)	+= codecs/ at91/ pxa/ s3c24xx/ sh/ fsl/
+obj-$(CONFIG_SND_SOC)	+= codecs/ at91/ pxa/ s3c24xx/ sh/ fsl/ omap/

sound/soc/omap/Kconfig

+menu "SoC Audio for the Texas Instruments OMAP"
+
+config SND_OMAP_SOC
+	tristate "SoC Audio for the Texas Instruments OMAP chips"
+	depends on ARCH_OMAP && SND_SOC
+
+config SND_OMAP_SOC_MCBSP
+	tristate
+	select OMAP_MCBSP
+
+config SND_OMAP_SOC_N810
+	tristate "SoC Audio support for Nokia N810"
+	depends on SND_OMAP_SOC && MACH_NOKIA_N810
+	select SND_OMAP_SOC_MCBSP
+	select SND_SOC_TLV320AIC3X
+	help
+	  Say Y if you want to add support for SoC audio on Nokia N810.
+
+endmenu

sound/soc/omap/Makefile

+# OMAP Platform Support
+snd-soc-omap-objs := omap-pcm.o
+snd-soc-omap-mcbsp-objs := omap-mcbsp.o
+
+obj-$(CONFIG_SND_OMAP_SOC) += snd-soc-omap.o
+obj-$(CONFIG_SND_OMAP_SOC_MCBSP) += snd-soc-omap-mcbsp.o
+
+# OMAP Machine Support
+snd-soc-n810-objs := n810.o
+
+obj-$(CONFIG_SND_OMAP_SOC_N810) += snd-soc-n810.o

sound/soc/omap/n810.c

+/*
+ * n810.c  --  SoC audio for Nokia N810
+ *
+ * Copyright (C) 2008 Nokia Corporation
+ *
+ * Contact: Jarkko Nikula <jarkko.nikula@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/soc.h>
+#include <sound/soc-dapm.h>
+
+#include <asm/mach-types.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/gpio.h>
+#include <asm/arch/mcbsp.h>
+
+#include "omap-mcbsp.h"
+#include "omap-pcm.h"
+#include "../codecs/tlv320aic3x.h"
+
+#define RX44_HEADSET_AMP_GPIO	10
+#define RX44_SPEAKER_AMP_GPIO	101
+
+static struct clk *sys_clkout2;
+static struct clk *sys_clkout2_src;
+static struct clk *func96m_clk;
+
+static int n810_spk_func;
+static int n810_jack_func;
+
+static void n810_ext_control(struct snd_soc_codec *codec)
+{
+	snd_soc_dapm_set_endpoint(codec, "Ext Spk", n810_spk_func);
+	snd_soc_dapm_set_endpoint(codec, "Headphone Jack", n810_jack_func);
+
+	snd_soc_dapm_sync_endpoints(codec);
+}
+
+static int n810_startup(struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_codec *codec = rtd->socdev->codec;
+
+	n810_ext_control(codec);
+	return clk_enable(sys_clkout2);
+}
+
+static void n810_shutdown(struct snd_pcm_substream *substream)
+{
+	clk_disable(sys_clkout2);
+}
+
+static int n810_hw_params(struct snd_pcm_substream *substream,
+	struct snd_pcm_hw_params *params)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_codec_dai *codec_dai = rtd->dai->codec_dai;
+	struct snd_soc_cpu_dai *cpu_dai = rtd->dai->cpu_dai;
+	int err;
+
+	/* Set codec DAI configuration */
+	err = codec_dai->dai_ops.set_fmt(codec_dai,
+					 SND_SOC_DAIFMT_I2S |
+					 SND_SOC_DAIFMT_NB_NF |
+					 SND_SOC_DAIFMT_CBM_CFM);
+	if (err < 0)
+		return err;
+
+	/* Set cpu DAI configuration */
+	err = cpu_dai->dai_ops.set_fmt(cpu_dai,
+				       SND_SOC_DAIFMT_I2S |
+				       SND_SOC_DAIFMT_NB_NF |
+				       SND_SOC_DAIFMT_CBM_CFM);
+	if (err < 0)
+		return err;
+
+	/* Set the codec system clock for DAC and ADC */
+	err = codec_dai->dai_ops.set_sysclk(codec_dai, 0, 12000000,
+					    SND_SOC_CLOCK_IN);
+
+	return err;
+}
+
+static struct snd_soc_ops n810_ops = {
+	.startup = n810_startup,
+	.hw_params = n810_hw_params,
+	.shutdown = n810_shutdown,
+};
+
+static int n810_get_spk(struct snd_kcontrol *kcontrol,
+			struct snd_ctl_elem_value *ucontrol)
+{
+	ucontrol->value.integer.value[0] = n810_spk_func;
+
+	return 0;
+}
+
+static int n810_set_spk(struct snd_kcontrol *kcontrol,
+			struct snd_ctl_elem_value *ucontrol)
+{
+	struct snd_soc_codec *codec =  snd_kcontrol_chip(kcontrol);
+
+	if (n810_spk_func == ucontrol->value.integer.value[0])
+		return 0;
+
+	n810_spk_func = ucontrol->value.integer.value[0];
+	n810_ext_control(codec);
+
+	return 1;
+}
+
+static int n810_get_jack(struct snd_kcontrol *kcontrol,
+			 struct snd_ctl_elem_value *ucontrol)
+{
+	ucontrol->value.integer.value[0] = n810_jack_func;
+
+	return 0;
+}
+
+static int n810_set_jack(struct snd_kcontrol *kcontrol,
+			 struct snd_ctl_elem_value *ucontrol)
+{
+	struct snd_soc_codec *codec =  snd_kcontrol_chip(kcontrol);
+
+	if (n810_jack_func == ucontrol->value.integer.value[0])
+		return 0;
+
+	n810_jack_func = ucontrol->value.integer.value[0];
+	n810_ext_control(codec);
+
+	return 1;
+}
+
+static int n810_spk_event(struct snd_soc_dapm_widget *w,
+			  struct snd_kcontrol *k, int event)
+{
+	if (SND_SOC_DAPM_EVENT_ON(event))
+		omap_set_gpio_dataout(RX44_SPEAKER_AMP_GPIO, 1);
+	else
+		omap_set_gpio_dataout(RX44_SPEAKER_AMP_GPIO, 0);
+
+	return 0;
+}
+
+static int n810_jack_event(struct snd_soc_dapm_widget *w,
+			   struct snd_kcontrol *k, int event)
+{
+	if (SND_SOC_DAPM_EVENT_ON(event))
+		omap_set_gpio_dataout(RX44_HEADSET_AMP_GPIO, 1);
+	else
+		omap_set_gpio_dataout(RX44_HEADSET_AMP_GPIO, 0);
+
+	return 0;
+}
+
+static const struct snd_soc_dapm_widget aic33_dapm_widgets[] = {
+	SND_SOC_DAPM_SPK("Ext Spk", n810_spk_event),
+	SND_SOC_DAPM_HP("Headphone Jack", n810_jack_event),
+};
+
+static const char *audio_map[][3] = {
+	{"Headphone Jack", NULL, "HPLOUT"},
+	{"Headphone Jack", NULL, "HPROUT"},
+
+	{"Ext Spk", NULL, "LLOUT"},
+	{"Ext Spk", NULL, "RLOUT"},
+};
+
+static const char *spk_function[] = {"Off", "On"};
+static const char *jack_function[] = {"Off", "Headphone"};
+static const struct soc_enum n810_enum[] = {
+	SOC_ENUM_SINGLE_EXT(2, spk_function),
+	SOC_ENUM_SINGLE_EXT(3, jack_function),
+};
+
+static const struct snd_kcontrol_new aic33_n810_controls[] = {
+	SOC_ENUM_EXT("Speaker Function", n810_enum[0],
+		     n810_get_spk, n810_set_spk),
+	SOC_ENUM_EXT("Jack Function", n810_enum[1],
+		     n810_get_jack, n810_set_jack),
+};
+
+static int n810_aic33_init(struct snd_soc_codec *codec)
+{
+	int i, err;
+
+	/* Not connected */
+	snd_soc_dapm_set_endpoint(codec, "MONO_LOUT", 0);
+	snd_soc_dapm_set_endpoint(codec, "HPLCOM", 0);
+	snd_soc_dapm_set_endpoint(codec, "HPRCOM", 0);
+
+	/* Add N810 specific controls */
+	for (i = 0; i < ARRAY_SIZE(aic33_n810_controls); i++) {
+		err = snd_ctl_add(codec->card,
+			snd_soc_cnew(&aic33_n810_controls[i], codec, NULL));
+		if (err < 0)
+			return err;
+	}
+
+	/* Add N810 specific widgets */
+	for (i = 0; i < ARRAY_SIZE(aic33_dapm_widgets); i++)
+		snd_soc_dapm_new_control(codec, &aic33_dapm_widgets[i]);
+
+	/* Set up N810 specific audio path audio_map */
+	for (i = 0; i < ARRAY_SIZE(audio_map); i++)
+		snd_soc_dapm_connect_input(codec, audio_map[i][0],
+			audio_map[i][1], audio_map[i][2]);
+
+	snd_soc_dapm_sync_endpoints(codec);
+
+	return 0;
+}
+
+/* Digital audio interface glue - connects codec <--> CPU */
+static struct snd_soc_dai_link n810_dai = {
+	.name = "TLV320AIC33",
+	.stream_name = "AIC33",
+	.cpu_dai = &omap_mcbsp_dai[0],
+	.codec_dai = &aic3x_dai,
+	.init = n810_aic33_init,
+	.ops = &n810_ops,
+};
+
+/* Audio machine driver */
+static struct snd_soc_machine snd_soc_machine_n810 = {
+	.name = "N810",
+	.dai_link = &n810_dai,
+	.num_links = 1,
+};
+
+/* Audio private data */
+static struct aic3x_setup_data n810_aic33_setup = {
+	.i2c_address = 0x18,
+};
+
+/* Audio subsystem */
+static struct snd_soc_device n810_snd_devdata = {
+	.machine = &snd_soc_machine_n810,
+	.platform = &omap_soc_platform,
+	.codec_dev = &soc_codec_dev_aic3x,
+	.codec_data = &n810_aic33_setup,
+};
+
+static struct platform_device *n810_snd_device;
+
+static int __init n810_soc_init(void)
+{
+	int err;
+	struct device *dev;
+
+	if (!machine_is_nokia_n810())
+		return -ENODEV;
+
+	n810_snd_device = platform_device_alloc("soc-audio", -1);
+	if (!n810_snd_device)
+		return -ENOMEM;
+
+	platform_set_drvdata(n810_snd_device, &n810_snd_devdata);
+	n810_snd_devdata.dev = &n810_snd_device->dev;
+	*(unsigned int *)n810_dai.cpu_dai->private_data = 1; /* McBSP2 */
+	err = platform_device_add(n810_snd_device);
+	if (err)
+		goto err1;
+
+	dev = &n810_snd_device->dev;
+
+	sys_clkout2_src = clk_get(dev, "sys_clkout2_src");
+	if (IS_ERR(sys_clkout2_src)) {
+		dev_err(dev, "Could not get sys_clkout2_src clock\n");
+		return -ENODEV;
+	}
+	sys_clkout2 = clk_get(dev, "sys_clkout2");
+	if (IS_ERR(sys_clkout2)) {
+		dev_err(dev, "Could not get sys_clkout2\n");
+		goto err1;
+	}
+	/*
+	 * Configure 12 MHz output on SYS_CLKOUT2. Therefore we must use
+	 * 96 MHz as its parent in order to get 12 MHz
+	 */
+	func96m_clk = clk_get(dev, "func_96m_ck");
+	if (IS_ERR(func96m_clk)) {
+		dev_err(dev, "Could not get func 96M clock\n");
+		goto err2;
+	}
+	clk_set_parent(sys_clkout2_src, func96m_clk);
+	clk_set_rate(sys_clkout2, 12000000);
+
+	if (omap_request_gpio(RX44_HEADSET_AMP_GPIO) < 0)
+		BUG();
+	if (omap_request_gpio(RX44_SPEAKER_AMP_GPIO) < 0)
+		BUG();
+	omap_set_gpio_direction(RX44_HEADSET_AMP_GPIO, 0);
+	omap_set_gpio_direction(RX44_SPEAKER_AMP_GPIO, 0);
+
+	return 0;
+err2:
+	clk_put(sys_clkout2);
+	platform_device_del(n810_snd_device);
+err1:
+	platform_device_put(n810_snd_device);
+
+	return err;
+
+}
+
+static void __exit n810_soc_exit(void)
+{
+	platform_device_unregister(n810_snd_device);
+}
+
+module_init(n810_soc_init);
+module_exit(n810_soc_exit);
+
+MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@nokia.com>");
+MODULE_DESCRIPTION("ALSA SoC Nokia N810");
+MODULE_LICENSE("GPL");

sound/soc/omap/omap-mcbsp.h

+/*
+ * omap-mcbsp.h
+ *
+ * Copyright (C) 2008 Nokia Corporation
+ *
+ * Contact: Jarkko Nikula <jarkko.nikula@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#ifndef __OMAP_I2S_H__
+#define __OMAP_I2S_H__
+
+/* Source clocks for McBSP sample rate generator */
+enum omap_mcbsp_clksrg_clk {
+	OMAP_MCBSP_SYSCLK_CLKS_FCLK,	/* Internal FCLK */
+	OMAP_MCBSP_SYSCLK_CLKS_EXT,	/* External CLKS pin */
+	OMAP_MCBSP_SYSCLK_CLK,		/* Internal ICLK */
+	OMAP_MCBSP_SYSCLK_CLKX_EXT,	/* External CLKX pin */
+	OMAP_MCBSP_SYSCLK_CLKR_EXT,	/* External CLKR pin */
+};
+
+/* McBSP dividers */
+enum omap_mcbsp_div {
+	OMAP_MCBSP_CLKGDV,		/* Sample rate generator divider */
+};
+
+/*
+ * REVISIT: Preparation for the ASoC v2. Let the number of available links to
+ * be same than number of McBSP ports found in OMAP(s) we are compiling for.
+ */
+#define NUM_LINKS	1
+
+extern struct snd_soc_cpu_dai omap_mcbsp_dai[NUM_LINKS];
+
+#endif

sound/soc/omap/omap-pcm.c

+/*
+ * omap-pcm.c  --  ALSA PCM interface for the OMAP SoC
+ *
+ * Copyright (C) 2008 Nokia Corporation
+ *
+ * Contact: Jarkko Nikula <jarkko.nikula@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#include <linux/dma-mapping.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#include <asm/arch/dma.h>
+#include "omap-pcm.h"
+
+static const struct snd_pcm_hardware omap_pcm_hardware = {
+	.info			= SNDRV_PCM_INFO_MMAP |
+				  SNDRV_PCM_INFO_MMAP_VALID |
+				  SNDRV_PCM_INFO_INTERLEAVED |
+				  SNDRV_PCM_INFO_PAUSE |
+				  SNDRV_PCM_INFO_RESUME,
+	.formats		= SNDRV_PCM_FMTBIT_S16_LE,
+	.period_bytes_min	= 32,
+	.period_bytes_max	= 64 * 1024,
+	.periods_min		= 2,
+	.periods_max		= 255,
+	.buffer_bytes_max	= 128 * 1024,
+};
+
+struct omap_runtime_data {
+	spinlock_t			lock;
+	struct omap_pcm_dma_data	*dma_data;
+	int				dma_ch;
+	int				period_index;
+};
+
+static void omap_pcm_dma_irq(int ch, u16 stat, void *data)
+{
+	struct snd_pcm_substream *substream = data;
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct omap_runtime_data *prtd = runtime->private_data;
+	unsigned long flags;
+
+	if (cpu_is_omap1510()) {
+		/*
+		 * OMAP1510 doesn't support DMA chaining so have to restart
+		 * the transfer after all periods are transferred
+		 */
+		spin_lock_irqsave(&prtd->lock, flags);
+		if (prtd->period_index >= 0) {
+			if (++prtd->period_index == runtime->periods) {
+				prtd->period_index = 0;
+				omap_start_dma(prtd->dma_ch);
+			}
+		}
+		spin_unlock_irqrestore(&prtd->lock, flags);
+	}
+
+	snd_pcm_period_elapsed(substream);
+}
+
+/* this may get called several times by oss emulation */
+static int omap_pcm_hw_params(struct snd_pcm_substream *substream,
+			      struct snd_pcm_hw_params *params)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct omap_runtime_data *prtd = runtime->private_data;
+	struct omap_pcm_dma_data *dma_data = rtd->dai->cpu_dai->dma_data;
+	int err = 0;
+
+	if (!dma_data)
+		return -ENODEV;
+
+	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
+	runtime->dma_bytes = params_buffer_bytes(params);
+
+	if (prtd->dma_data)
+		return 0;
+	prtd->dma_data = dma_data;
+	err = omap_request_dma(dma_data->dma_req, dma_data->name,
+			       omap_pcm_dma_irq, substream, &prtd->dma_ch);
+	if (!cpu_is_omap1510()) {
+		/*
+		 * Link channel with itself so DMA doesn't need any
+		 * reprogramming while looping the buffer
+		 */
+		omap_dma_link_lch(prtd->dma_ch, prtd->dma_ch);
+	}
+
+	return err;
+}
+
+static int omap_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct omap_runtime_data *prtd = runtime->private_data;
+
+	if (prtd->dma_data == NULL)
+		return 0;
+
+	if (!cpu_is_omap1510())
+		omap_dma_unlink_lch(prtd->dma_ch, prtd->dma_ch);
+	omap_free_dma(prtd->dma_ch);
+	prtd->dma_data = NULL;
+
+	snd_pcm_set_runtime_buffer(substream, NULL);
+
+	return 0;
+}
+
+static int omap_pcm_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct omap_runtime_data *prtd = runtime->private_data;
+	struct omap_pcm_dma_data *dma_data = prtd->dma_data;
+	struct omap_dma_channel_params dma_params;
+
+	memset(&dma_params, 0, sizeof(dma_params));
+	/*
+	 * Note: Regardless of interface data formats supported by OMAP McBSP
+	 * or EAC blocks, internal representation is always fixed 16-bit/sample
+	 */
+	dma_params.data_type			= OMAP_DMA_DATA_TYPE_S16;
+	dma_params.trigger			= dma_data->dma_req;
+	dma_params.sync_mode			= OMAP_DMA_SYNC_ELEMENT;
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		dma_params.src_amode		= OMAP_DMA_AMODE_POST_INC;
+		dma_params.dst_amode		= OMAP_DMA_AMODE_CONSTANT;
+		dma_params.src_or_dst_synch	= OMAP_DMA_DST_SYNC;
+		dma_params.src_start		= runtime->dma_addr;
+		dma_params.dst_start		= dma_data->port_addr;
+	} else {
+		dma_params.src_amode		= OMAP_DMA_AMODE_CONSTANT;
+		dma_params.dst_amode		= OMAP_DMA_AMODE_POST_INC;
+		dma_params.src_or_dst_synch	= OMAP_DMA_SRC_SYNC;
+		dma_params.src_start		= dma_data->port_addr;
+		dma_params.dst_start		= runtime->dma_addr;
+	}
+	/*
+	 * Set DMA transfer frame size equal to ALSA period size and frame
+	 * count as no. of ALSA periods. Then with DMA frame interrupt enabled,
+	 * we can transfer the whole ALSA buffer with single DMA transfer but
+	 * still can get an interrupt at each period bounary
+	 */
+	dma_params.elem_count	= snd_pcm_lib_period_bytes(substream) / 2;
+	dma_params.frame_count	= runtime->periods;
+	omap_set_dma_params(prtd->dma_ch, &dma_params);
+
+	omap_enable_dma_irq(prtd->dma_ch, OMAP_DMA_FRAME_IRQ);
+
+	return 0;
+}
+
+static int omap_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct omap_runtime_data *prtd = runtime->private_data;
+	int ret = 0;
+
+	spin_lock_irq(&prtd->lock);
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		prtd->period_index = 0;
+		omap_start_dma(prtd->dma_ch);
+		break;
+
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		prtd->period_index = -1;
+		omap_stop_dma(prtd->dma_ch);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+	spin_unlock_irq(&prtd->lock);
+
+	return ret;
+}
+
+static snd_pcm_uframes_t omap_pcm_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct omap_runtime_data *prtd = runtime->private_data;
+	dma_addr_t ptr;
+	snd_pcm_uframes_t offset;
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		ptr = omap_get_dma_src_pos(prtd->dma_ch);
+	else
+		ptr = omap_get_dma_dst_pos(prtd->dma_ch);
+
+	offset = bytes_to_frames(runtime, ptr - runtime->dma_addr);
+	if (offset >= runtime->buffer_size)
+		offset = 0;
+
+	return offset;
+}
+
+static int omap_pcm_open(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct omap_runtime_data *prtd;
+	int ret;
+
+	snd_soc_set_runtime_hwparams(substream, &omap_pcm_hardware);
+
+	/* Ensure that buffer size is a multiple of period size */
+	ret = snd_pcm_hw_constraint_integer(runtime,
+					    SNDRV_PCM_HW_PARAM_PERIODS);
+	if (ret < 0)
+		goto out;
+
+	prtd = kzalloc(sizeof(prtd), GFP_KERNEL);
+	if (prtd == NULL) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	spin_lock_init(&prtd->lock);
+	runtime->private_data = prtd;
+
+out:
+	return ret;
+}
+
+static int omap_pcm_close(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+
+	kfree(runtime->private_data);
+	return 0;
+}
+
+static int omap_pcm_mmap(struct snd_pcm_substream *substream,
+	struct vm_area_struct *vma)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+
+	return dma_mmap_writecombine(substream->pcm->card->dev, vma,
+				     runtime->dma_area,
+				     runtime->dma_addr,
+				     runtime->dma_bytes);
+}
+
+struct snd_pcm_ops omap_pcm_ops = {
+	.open		= omap_pcm_open,
+	.close		= omap_pcm_close,
+	.ioctl		= snd_pcm_lib_ioctl,
+	.hw_params	= omap_pcm_hw_params,
+	.hw_free	= omap_pcm_hw_free,
+	.prepare	= omap_pcm_prepare,
+	.trigger	= omap_pcm_trigger,
+	.pointer	= omap_pcm_pointer,
+	.mmap		= omap_pcm_mmap,
+};
+
+static u64 omap_pcm_dmamask = DMA_BIT_MASK(32);
+
+static int omap_pcm_preallocate_dma_buffer(struct snd_pcm *pcm,
+	int stream)
+{
+	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
+	struct snd_dma_buffer *buf = &substream->dma_buffer;
+	size_t size = omap_pcm_hardware.buffer_bytes_max;
+
+	buf->dev.type = SNDRV_DMA_TYPE_DEV;
+	buf->dev.dev = pcm->card->dev;
+	buf->private_data = NULL;
+	buf->area = dma_alloc_writecombine(pcm->card->dev, size,
+					   &buf->addr, GFP_KERNEL);
+	if (!buf->area)
+		return -ENOMEM;
+
+	buf->bytes = size;
+	return 0;
+}
+
+static void omap_pcm_free_dma_buffers(struct snd_pcm *pcm)
+{
+	struct snd_pcm_substream *substream;
+	struct snd_dma_buffer *buf;
+	int stream;
+
+	for (stream = 0; stream < 2; stream++) {
+		substream = pcm->streams[stream].substream;
+		if (!substream)
+			continue;
+
+		buf = &substream->dma_buffer;
+		if (!buf->area)
+			continue;
+
+		dma_free_writecombine(pcm->card->dev, buf->bytes,
+				      buf->area, buf->addr);
+		buf->area = NULL;
+	}
+}
+
+int omap_pcm_new(struct snd_card *card, struct snd_soc_codec_dai *dai,
+		 struct snd_pcm *pcm)
+{
+	int ret = 0;
+
+	if (!card->dev->dma_mask)
+		card->dev->dma_mask = &omap_pcm_dmamask;
+	if (!card->dev->coherent_dma_mask)
+		card->dev->coherent_dma_mask = DMA_32BIT_MASK;
+
+	if (dai->playback.channels_min) {
+		ret = omap_pcm_preallocate_dma_buffer(pcm,
+			SNDRV_PCM_STREAM_PLAYBACK);
+		if (ret)
+			goto out;
+	}
+
+	if (dai->capture.channels_min) {
+		ret = omap_pcm_preallocate_dma_buffer(pcm,
+			SNDRV_PCM_STREAM_CAPTURE);
+		if (ret)
+			goto out;
+	}
+
+out:
+	return ret;
+}
+
+struct snd_soc_platform omap_soc_platform = {
+	.name		= "omap-pcm-audio",
+	.pcm_ops 	= &omap_pcm_ops,
+	.pcm_new	= omap_pcm_new,
+	.pcm_free	= omap_pcm_free_dma_buffers,
+};
+EXPORT_SYMBOL_GPL(omap_soc_platform);
+
+MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@nokia.com>");
+MODULE_DESCRIPTION("OMAP PCM DMA module");
+MODULE_LICENSE("GPL");

sound/soc/omap/omap-pcm.h

+/*
+ * omap-pcm.h
+ *
+ * Copyright (C) 2008 Nokia Corporation
+ *
+ * Contact: Jarkko Nikula <jarkko.nikula@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#ifndef __OMAP_PCM_H__
+#define __OMAP_PCM_H__
+
+struct omap_pcm_dma_data {
+	char		*name;		/* stream identifier */
+	int		dma_req;	/* DMA request line */
+	unsigned long	port_addr;	/* transmit/receive register */
+};
+
+extern struct snd_soc_platform omap_soc_platform;
+
+#endif