Re: [RFC][PATCH 21/26] alsa: ASoC: Add JZ4740 ASoC support

[Liam Girdwood <lrg@slimlogic.co.uk>]

On Wed, 2010-06-02 at 21:12 +0200, Lars-Peter Clausen wrote:
> This patch adds ASoC support for JZ4740 SoCs I2S module.
> 
> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
> Cc: Liam Girdwood <lrg@slimlogic.co.uk>
> Cc: alsa-devel@alsa-project.org
> ---
>  sound/soc/Kconfig             |    1 +
>  sound/soc/Makefile            |    1 +
>  sound/soc/jz4740/Kconfig      |   13 +
>  sound/soc/jz4740/Makefile     |    9 +
>  sound/soc/jz4740/jz4740-i2s.c |  568 +++++++++++++++++++++++++++++++++++++++++
>  sound/soc/jz4740/jz4740-i2s.h |   18 ++
>  sound/soc/jz4740/jz4740-pcm.c |  350 +++++++++++++++++++++++++
>  sound/soc/jz4740/jz4740-pcm.h |   22 ++
>  8 files changed, 982 insertions(+), 0 deletions(-)
>  create mode 100644 sound/soc/jz4740/Kconfig
>  create mode 100644 sound/soc/jz4740/Makefile
>  create mode 100644 sound/soc/jz4740/jz4740-i2s.c
>  create mode 100644 sound/soc/jz4740/jz4740-i2s.h
>  create mode 100644 sound/soc/jz4740/jz4740-pcm.c
>  create mode 100644 sound/soc/jz4740/jz4740-pcm.h
> 
> diff --git a/sound/soc/Kconfig b/sound/soc/Kconfig
> index b1749bc..5a7a724 100644
> --- a/sound/soc/Kconfig
> +++ b/sound/soc/Kconfig
> @@ -36,6 +36,7 @@ source "sound/soc/s3c24xx/Kconfig"
>  source "sound/soc/s6000/Kconfig"
>  source "sound/soc/sh/Kconfig"
>  source "sound/soc/txx9/Kconfig"
> +source "sound/soc/jz4740/Kconfig"
>  
>  # Supported codecs
>  source "sound/soc/codecs/Kconfig"
> diff --git a/sound/soc/Makefile b/sound/soc/Makefile
> index 1470141..fdbe74d 100644
> --- a/sound/soc/Makefile
> +++ b/sound/soc/Makefile
> @@ -14,3 +14,4 @@ obj-$(CONFIG_SND_SOC)	+= s3c24xx/
>  obj-$(CONFIG_SND_SOC)	+= s6000/
>  obj-$(CONFIG_SND_SOC)	+= sh/
>  obj-$(CONFIG_SND_SOC)	+= txx9/
> +obj-$(CONFIG_SND_SOC)	+= jz4740/
> diff --git a/sound/soc/jz4740/Kconfig b/sound/soc/jz4740/Kconfig
> new file mode 100644
> index 0000000..39df949
> --- /dev/null
> +++ b/sound/soc/jz4740/Kconfig
> @@ -0,0 +1,13 @@
> +config SND_JZ4740_SOC
> +	tristate "SoC Audio for Ingenic JZ4740 SoC"
> +	depends on SOC_JZ4740 && SND_SOC
> +	help
> +	  Say Y or M if you want to add support for codecs attached to
> +	  the Jz4740 AC97, I2S or SSP interface. You will also need

Do you have an AC97 or SSP interface ?

> +	  to select the audio interfaces to support below.
> +
> +config SND_JZ4740_SOC_I2S
> +	depends on SND_JZ4740_SOC
> +	tristate "SoC Audio (I2S protocol) for Ingenic jz4740 chip"
> +	help
> +	  Say Y if you want to use I2S protocol and I2S codec on Ingenic Jz4740 QI_LB60 board.
> diff --git a/sound/soc/jz4740/Makefile b/sound/soc/jz4740/Makefile
> new file mode 100644
> index 0000000..1be8d19
> --- /dev/null
> +++ b/sound/soc/jz4740/Makefile
> @@ -0,0 +1,9 @@
> +#
> +# Jz4740 Platform Support
> +#
> +snd-soc-jz4740-objs := jz4740-pcm.o
> +snd-soc-jz4740-i2s-objs := jz4740-i2s.o
> +
> +obj-$(CONFIG_SND_JZ4740_SOC) += snd-soc-jz4740.o
> +obj-$(CONFIG_SND_JZ4740_SOC_I2S) += snd-soc-jz4740-i2s.o
> +
> diff --git a/sound/soc/jz4740/jz4740-i2s.c b/sound/soc/jz4740/jz4740-i2s.c
> new file mode 100644
> index 0000000..2b139fd
> --- /dev/null
> +++ b/sound/soc/jz4740/jz4740-i2s.c
> @@ -0,0 +1,568 @@
> +/*
> + *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
> + *
> + *  This program is free software; you can redistribute	 it and/or modify it
> + *  under  the terms of	 the GNU General  Public License as published by the
> + *  Free Software Foundation;  either version 2 of the	License, or (at your
> + *  option) any later version.
> + *

Formatting looks broken here.

> + *  You should have received a copy of the  GNU General Public License along
> + *  with this program; if not, write  to the Free Software Foundation, Inc.,
> + *  675 Mass Ave, Cambridge, MA 02139, USA.
> + *
> + */
> +
> +#include <linux/init.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +
> +#include <linux/dma-mapping.h>
> +
> +#include <sound/core.h>
> +#include <sound/pcm.h>
> +#include <sound/pcm_params.h>
> +#include <sound/soc.h>
> +#include <sound/soc-dapm.h>
> +#include <sound/initval.h>
> +
> +#include "jz4740-i2s.h"
> +#include "jz4740-pcm.h"
> +
> +#define JZ_REG_AIC_CONF		0x00
> +#define JZ_REG_AIC_CTRL		0x04
> +#define JZ_REG_AIC_I2S_FMT	0x10
> +#define JZ_REG_AIC_FIFO_STATUS	0x14
> +#define JZ_REG_AIC_I2S_STATUS	0x1c
> +#define JZ_REG_AIC_CLK_DIV	0x30
> +#define JZ_REG_AIC_FIFO		0x34
> +
> +#define JZ_AIC_CONF_FIFO_RX_THRESHOLD_MASK (0xf << 12)
> +#define JZ_AIC_CONF_FIFO_TX_THRESHOLD_MASK (0xf <<  8)
> +#define JZ_AIC_CONF_OVERFLOW_PLAY_LAST BIT(6)
> +#define JZ_AIC_CONF_INTERNAL_CODEC BIT(5)
> +#define JZ_AIC_CONF_I2S BIT(4)
> +#define JZ_AIC_CONF_RESET BIT(3)
> +#define JZ_AIC_CONF_BIT_CLK_MASTER BIT(2)
> +#define JZ_AIC_CONF_SYNC_CLK_MASTER BIT(1)
> +#define JZ_AIC_CONF_ENABLE BIT(0)
> +
> +#define JZ_AIC_CONF_FIFO_RX_THRESHOLD_OFFSET 12
> +#define JZ_AIC_CONF_FIFO_TX_THRESHOLD_OFFSET 8
> +
> +#define JZ_AIC_CTRL_OUTPUT_SAMPLE_SIZE_MASK (0x7 << 19)
> +#define JZ_AIC_CTRL_INPUT_SAMPLE_SIZE_MASK (0x7 << 16)
> +#define JZ_AIC_CTRL_ENABLE_RX_DMA BIT(15)
> +#define JZ_AIC_CTRL_ENABLE_TX_DMA BIT(14)
> +#define JZ_AIC_CTRL_MONO_TO_STEREO BIT(11)
> +#define JZ_AIC_CTRL_SWITCH_ENDIANNESS BIT(10)
> +#define JZ_AIC_CTRL_SIGNED_TO_UNSIGNED BIT(9)
> +#define JZ_AIC_CTRL_FLUSH		BIT(8)
> +#define JZ_AIC_CTRL_ENABLE_ROR_INT BIT(6)
> +#define JZ_AIC_CTRL_ENABLE_TUR_INT BIT(5)
> +#define JZ_AIC_CTRL_ENABLE_RFS_INT BIT(4)
> +#define JZ_AIC_CTRL_ENABLE_TFS_INT BIT(3)
> +#define JZ_AIC_CTRL_ENABLE_LOOPBACK BIT(2)
> +#define JZ_AIC_CTRL_ENABLE_PLAYBACK BIT(1)
> +#define JZ_AIC_CTRL_ENABLE_CAPTURE BIT(0)
> +
> +#define JZ_AIC_CTRL_OUTPUT_SAMPLE_SIZE_OFFSET 19
> +#define JZ_AIC_CTRL_INPUT_SAMPLE_SIZE_OFFSET  16
> +
> +#define JZ_AIC_I2S_FMT_DISABLE_BIT_CLK BIT(12)
> +#define JZ_AIC_I2S_FMT_ENABLE_SYS_CLK BIT(4)
> +#define JZ_AIC_I2S_FMT_MSB BIT(0)
> +
> +#define JZ_AIC_I2S_STATUS_BUSY BIT(2)
> +
> +#define JZ_AIC_CLK_DIV_MASK 0xf
> +
> +struct jz4740_i2s {
> +	struct resource *mem;
> +	void __iomem *base;
> +	dma_addr_t phys_base;
> +
> +	struct clk *clk_aic;
> +	struct clk *clk_i2s;
> +
> +	struct jz4740_pcm_config pcm_config_playback;
> +	struct jz4740_pcm_config pcm_config_capture;
> +};
> +
> +static inline uint32_t jz4740_i2s_read(const struct jz4740_i2s *i2s,
> +	unsigned int reg)
> +{
> +	return readl(i2s->base + reg);
> +}
> +
> +static inline void jz4740_i2s_write(const struct jz4740_i2s *i2s,
> +	unsigned int reg, uint32_t value)
> +{
> +	writel(value, i2s->base + reg);
> +}
> +
> +static inline struct jz4740_i2s *jz4740_dai_to_i2s(struct snd_soc_dai *dai)
> +{
> +	return dai->private_data;
> +}
> +
> +static int jz4740_i2s_startup(struct snd_pcm_substream *substream,
> +	struct snd_soc_dai *dai)
> +{
> +	struct jz4740_i2s *i2s = jz4740_dai_to_i2s(dai);
> +	uint32_t conf, ctrl;
> +
> +	if (dai->active)
> +		return 0;
> +
> +
> +	ctrl = jz4740_i2s_read(i2s, JZ_REG_AIC_CTRL);
> +	ctrl |= JZ_AIC_CTRL_FLUSH;
> +	jz4740_i2s_write(i2s, JZ_REG_AIC_CTRL, ctrl);
> +
> +	clk_enable(i2s->clk_i2s);
> +
> +	conf = jz4740_i2s_read(i2s, JZ_REG_AIC_CONF);
> +	conf |= JZ_AIC_CONF_ENABLE;
> +	jz4740_i2s_write(i2s, JZ_REG_AIC_CONF, conf);
> +
> +	return 0;
> +}
> +
> +static void jz4740_i2s_shutdown(struct snd_pcm_substream *substream,
> +	struct snd_soc_dai *dai)
> +{
> +	struct jz4740_i2s *i2s = jz4740_dai_to_i2s(dai);
> +	uint32_t conf;
> +
> +	if (!dai->active)
> +		return;
> +
> +	conf = jz4740_i2s_read(i2s, JZ_REG_AIC_CONF);
> +	conf &= ~JZ_AIC_CONF_ENABLE;
> +	jz4740_i2s_write(i2s, JZ_REG_AIC_CONF, conf);
> +
> +	clk_disable(i2s->clk_i2s);
> +}
> +
> +
> +static int jz4740_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
> +	struct snd_soc_dai *dai)
> +{
> +	struct jz4740_i2s *i2s = jz4740_dai_to_i2s(dai);
> +	bool playback = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK);
> +
> +	uint32_t ctrl;
> +	uint32_t mask;
> +
> +	if (playback)

It's best to use (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) here.

> +		mask = JZ_AIC_CTRL_ENABLE_PLAYBACK | JZ_AIC_CTRL_ENABLE_TX_DMA;
> +	else
> +		mask = JZ_AIC_CTRL_ENABLE_CAPTURE | JZ_AIC_CTRL_ENABLE_RX_DMA;
> +
> +	ctrl = jz4740_i2s_read(i2s, JZ_REG_AIC_CTRL);
> +
> +	switch (cmd) {
> +	case SNDRV_PCM_TRIGGER_START:
> +	case SNDRV_PCM_TRIGGER_RESUME:
> +	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
> +		ctrl |= mask;
> +		break;
> +	case SNDRV_PCM_TRIGGER_STOP:
> +	case SNDRV_PCM_TRIGGER_SUSPEND:
> +	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
> +		ctrl &= ~mask;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	jz4740_i2s_write(i2s, JZ_REG_AIC_CTRL, ctrl);
> +
> +	return 0;
> +}
> +
> +
> +static int jz4740_i2s_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
> +{
> +	struct jz4740_i2s *i2s = jz4740_dai_to_i2s(dai);
> +

No new line is required here.

> +	uint32_t format = 0;
> +	uint32_t conf;
> +
> +	conf = jz4740_i2s_read(i2s, JZ_REG_AIC_CONF);
> +
> +	conf &= ~(JZ_AIC_CONF_BIT_CLK_MASTER | JZ_AIC_CONF_SYNC_CLK_MASTER);
> +
> +	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
> +	case SND_SOC_DAIFMT_CBS_CFS:
> +		conf |= JZ_AIC_CONF_BIT_CLK_MASTER | JZ_AIC_CONF_SYNC_CLK_MASTER;
> +		format |= JZ_AIC_I2S_FMT_ENABLE_SYS_CLK;
> +		break;
> +	case SND_SOC_DAIFMT_CBM_CFS:
> +		conf |= JZ_AIC_CONF_SYNC_CLK_MASTER;
> +		break;
> +	case SND_SOC_DAIFMT_CBS_CFM:
> +		conf |= JZ_AIC_CONF_BIT_CLK_MASTER;
> +		break;
> +	case SND_SOC_DAIFMT_CBM_CFM:
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
> +	case SND_SOC_DAIFMT_MSB:
> +		format |= JZ_AIC_I2S_FMT_MSB;
> +		break;
> +	case SND_SOC_DAIFMT_I2S:
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
> +	case SND_SOC_DAIFMT_NB_NF:
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	jz4740_i2s_write(i2s, JZ_REG_AIC_CONF, conf);
> +	jz4740_i2s_write(i2s, JZ_REG_AIC_I2S_FMT, format);
> +
> +	return 0;
> +}
> +
> +static int jz4740_i2s_hw_params(struct snd_pcm_substream *substream,
> +	struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
> +{
> +	struct jz4740_i2s *i2s = jz4740_dai_to_i2s(dai);
> +	bool playback = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK);
> +	enum jz4740_dma_width dma_width;
> +	struct jz4740_pcm_config *pcm_config;
> +	unsigned int sample_size;
> +	uint32_t ctrl;
> +
> +	ctrl = jz4740_i2s_read(i2s, JZ_REG_AIC_CTRL);
> +
> +	switch (params_format(params)) {
> +	case SNDRV_PCM_FORMAT_S8:
> +		sample_size = 0;
> +		dma_width = JZ4740_DMA_WIDTH_8BIT;
> +		break;
> +	case SNDRV_PCM_FORMAT_S16:
> +		sample_size = 1;
> +		dma_width = JZ4740_DMA_WIDTH_16BIT;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	if (playback) {

Same here re substream->stream

> +		ctrl &= ~JZ_AIC_CTRL_OUTPUT_SAMPLE_SIZE_MASK;
> +		ctrl |= sample_size << JZ_AIC_CTRL_OUTPUT_SAMPLE_SIZE_OFFSET;
> +	} else {
> +		ctrl &= ~JZ_AIC_CTRL_INPUT_SAMPLE_SIZE_MASK;
> +		ctrl |= sample_size << JZ_AIC_CTRL_INPUT_SAMPLE_SIZE_OFFSET;
> +	}
> +
> +	switch (params_channels(params)) {
> +	case 2:
> +		break;
> +	case 1:
> +		if (playback) {
> +			ctrl |= JZ_AIC_CTRL_MONO_TO_STEREO;
> +			break;
> +		}
> +	default: /* Falltrough */
> +		return -EINVAL;
> +	}
> +
> +	jz4740_i2s_write(i2s, JZ_REG_AIC_CTRL, ctrl);
> +
> +	if (playback) {

ditto
> +		pcm_config = &i2s->pcm_config_playback;
> +		pcm_config->dma_config.dst_width = dma_width;
> +	} else {
> +		pcm_config = &i2s->pcm_config_capture;
> +		pcm_config->dma_config.src_width = dma_width;
> +	}
> +
> +
> +	snd_soc_dai_set_dma_data(dai, substream, pcm_config);
> +
> +	return 0;
> +}
> +
> +static int jz4740_i2s_set_clkdiv(struct snd_soc_dai *dai, int div_id, int div)
> +{
> +	struct jz4740_i2s *i2s = jz4740_dai_to_i2s(dai);
> +
> +	switch (div_id) {
> +	case JZ4740_I2S_BIT_CLK:
> +		if (div & 1 || div > 16)
> +			return -EINVAL;
> +		jz4740_i2s_write(i2s, JZ_REG_AIC_CLK_DIV, div - 1);
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static int jz4740_i2s_set_sysclk(struct snd_soc_dai *dai, int clk_id,
> +	unsigned int freq, int dir)
> +{
> +	struct jz4740_i2s *i2s = jz4740_dai_to_i2s(dai);
> +	int ret = 0;
> +	struct clk *parent;
> +
> +	switch (clk_id) {
> +	case JZ4740_I2S_CLKSRC_EXT:
> +		parent = clk_get(NULL, "ext");
> +		clk_set_parent(i2s->clk_i2s, parent);
> +		break;
> +	case JZ4740_I2S_CLKSRC_PLL:
> +		parent = clk_get(NULL, "pll half");
> +		clk_set_parent(i2s->clk_i2s, parent);
> +		ret = clk_set_rate(i2s->clk_i2s, freq);
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +	clk_put(parent);
> +
> +	return ret;
> +}
> +
> +static int jz4740_i2s_suspend(struct snd_soc_dai *dai)
> +{
> +	struct jz4740_i2s *i2s = jz4740_dai_to_i2s(dai);
> +	uint32_t conf;
> +
> +	if (dai->active) {
> +		conf = jz4740_i2s_read(i2s, JZ_REG_AIC_CONF);
> +		conf &= ~JZ_AIC_CONF_ENABLE;
> +		jz4740_i2s_write(i2s, JZ_REG_AIC_CONF, conf);
> +
> +		clk_disable(i2s->clk_i2s);
> +	}
> +
> +	clk_disable(i2s->clk_aic);
> +
> +	return 0;
> +}
> +
> +static int jz4740_i2s_resume(struct snd_soc_dai *dai)
> +{
> +	struct jz4740_i2s *i2s = jz4740_dai_to_i2s(dai);
> +	uint32_t conf;
> +
> +	clk_enable(i2s->clk_aic);
> +
> +	if (dai->active) {
> +		clk_enable(i2s->clk_i2s);
> +
> +		conf = jz4740_i2s_read(i2s, JZ_REG_AIC_CONF);
> +		conf |= JZ_AIC_CONF_ENABLE;
> +		jz4740_i2s_write(i2s, JZ_REG_AIC_CONF, conf);
> +
> +	}
> +
> +	return 0;
> +}
> +
> +static int jz4740_i2s_probe(struct platform_device *pdev, struct snd_soc_dai *dai)
> +{
> +	struct jz4740_i2s *i2s = jz4740_dai_to_i2s(dai);
> +	uint32_t conf;
> +
> +	conf = (7 << JZ_AIC_CONF_FIFO_RX_THRESHOLD_OFFSET) |
> +		(8 << JZ_AIC_CONF_FIFO_TX_THRESHOLD_OFFSET) |
> +		JZ_AIC_CONF_OVERFLOW_PLAY_LAST |
> +		JZ_AIC_CONF_I2S |
> +		JZ_AIC_CONF_INTERNAL_CODEC;
> +
> +	jz4740_i2s_write(i2s, JZ_REG_AIC_CONF, JZ_AIC_CONF_RESET);
> +	jz4740_i2s_write(i2s, JZ_REG_AIC_CONF, conf);
> +
> +	return 0;
> +}
> +
> +
> +static struct snd_soc_dai_ops jz4740_i2s_dai_ops = {
> +	.startup = jz4740_i2s_startup,
> +	.shutdown = jz4740_i2s_shutdown,
> +	.trigger = jz4740_i2s_trigger,
> +	.hw_params = jz4740_i2s_hw_params,
> +	.set_fmt = jz4740_i2s_set_fmt,
> +	.set_clkdiv = jz4740_i2s_set_clkdiv,
> +	.set_sysclk = jz4740_i2s_set_sysclk,
> +};
> +
> +#define JZ4740_I2S_FMTS (SNDRV_PCM_FMTBIT_S8 | \
> +		SNDRV_PCM_FMTBIT_S16_LE)
> +
> +struct snd_soc_dai jz4740_i2s_dai = {
> +	.name = "jz4740-i2s",
> +	.probe = jz4740_i2s_probe,
> +	.playback = {
> +		.channels_min = 1,
> +		.channels_max = 2,
> +		.rates = SNDRV_PCM_RATE_8000_48000,
> +		.formats = JZ4740_I2S_FMTS,
> +	},
> +	.capture = {
> +		.channels_min = 2,
> +		.channels_max = 2,
> +		.rates = SNDRV_PCM_RATE_8000_48000,
> +		.formats = JZ4740_I2S_FMTS,
> +	},
> +	.symmetric_rates = 1,
> +	.ops = &jz4740_i2s_dai_ops,
> +	.suspend = jz4740_i2s_suspend,
> +	.resume = jz4740_i2s_resume,
> +};
> +EXPORT_SYMBOL_GPL(jz4740_i2s_dai);
> +
> +static void __devinit jz4740_i2c_init_pcm_config(struct jz4740_i2s *i2s)
> +{
> +	struct jz4740_dma_config *dma_config;
> +
> +	/* Playback */
> +	dma_config = &i2s->pcm_config_playback.dma_config;
> +	dma_config->src_width = JZ4740_DMA_WIDTH_32BIT,
> +	dma_config->transfer_size = JZ4740_DMA_TRANSFER_SIZE_16BYTE;
> +	dma_config->request_type = JZ4740_DMA_TYPE_AIC_TRANSMIT;
> +	dma_config->flags = JZ4740_DMA_SRC_AUTOINC;
> +	dma_config->mode = JZ4740_DMA_MODE_SINGLE;
> +	i2s->pcm_config_playback.fifo_addr = i2s->phys_base + JZ_REG_AIC_FIFO;
> +
> +	/* Capture */
> +	dma_config = &i2s->pcm_config_capture.dma_config;
> +	dma_config->dst_width = JZ4740_DMA_WIDTH_32BIT,
> +	dma_config->transfer_size = JZ4740_DMA_TRANSFER_SIZE_16BYTE;
> +	dma_config->request_type = JZ4740_DMA_TYPE_AIC_RECEIVE;
> +	dma_config->flags = JZ4740_DMA_DST_AUTOINC;
> +	dma_config->mode = JZ4740_DMA_MODE_SINGLE;
> +	i2s->pcm_config_capture.fifo_addr = i2s->phys_base + JZ_REG_AIC_FIFO;
> +}
> +
> +static int __devinit jz4740_i2s_dev_probe(struct platform_device *pdev)
> +{
> +	struct jz4740_i2s *i2s;
> +	int ret;
> +
> +	i2s = kzalloc(sizeof(*i2s), GFP_KERNEL);
> +
> +	if (!i2s)
> +		return -ENOMEM;
> +
> +	i2s->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +

Why the new lines here

> +	if (!i2s->mem) {
> +		ret = -ENOENT;
> +		goto err_free;
> +	}
> +
> +	i2s->mem = request_mem_region(i2s->mem->start, resource_size(i2s->mem),
> +				pdev->name);
> +

and here

> +	if (!i2s->mem) {
> +		ret = -EBUSY;
> +		goto err_free;
> +	}
> +
> +	i2s->base = ioremap_nocache(i2s->mem->start, resource_size(i2s->mem));
> +

ditto

> +	if (!i2s->base) {
> +		ret = -EBUSY;
> +		goto err_release_mem_region;
> +	}
> +
> +	i2s->phys_base = i2s->mem->start;
> +
> +	i2s->clk_aic = clk_get(&pdev->dev, "aic");
> +	if (IS_ERR(i2s->clk_aic)) {
> +		ret = PTR_ERR(i2s->clk_aic);
> +		goto err_iounmap;
> +	}
> +
> +	i2s->clk_i2s = clk_get(&pdev->dev, "i2s");
> +	if (IS_ERR(i2s->clk_i2s)) {
> +		ret = PTR_ERR(i2s->clk_i2s);
> +		goto err_iounmap;
> +	}
> +
> +	clk_enable(i2s->clk_aic);
> +
> +	jz4740_i2c_init_pcm_config(i2s);
> +
> +	jz4740_i2s_dai.private_data = i2s;
> +	ret = snd_soc_register_dai(&jz4740_i2s_dai);
> +
> +	platform_set_drvdata(pdev, i2s);
> +
> +	return 0;
> +
> +err_iounmap:
> +	iounmap(i2s->base);
> +err_release_mem_region:
> +	release_mem_region(i2s->mem->start, resource_size(i2s->mem));
> +err_free:
> +	kfree(i2s);
> +
> +	return ret;
> +}
> +
> +static int __devexit jz4740_i2s_dev_remove(struct platform_device *pdev)
> +{
> +	struct jz4740_i2s *i2s = platform_get_drvdata(pdev);
> +
> +	snd_soc_unregister_dai(&jz4740_i2s_dai);
> +
> +	clk_disable(i2s->clk_aic);
> +	clk_put(i2s->clk_i2s);
> +	clk_put(i2s->clk_aic);
> +
> +	iounmap(i2s->base);
> +	release_mem_region(i2s->mem->start, resource_size(i2s->mem));
> +
> +	platform_set_drvdata(pdev, NULL);
> +	kfree(i2s);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver jz4740_i2s_driver = {
> +	.probe = jz4740_i2s_dev_probe,
> +	.remove = __devexit_p(jz4740_i2s_dev_remove),
> +	.driver = {
> +		.name = "jz4740-i2s",
> +		.owner = THIS_MODULE,
> +	},
> +};
> +
> +static int __init jz4740_i2s_init(void)
> +{
> +	return platform_driver_register(&jz4740_i2s_driver);
> +}
> +module_init(jz4740_i2s_init);
> +
> +static void __exit jz4740_i2s_exit(void)
> +{
> +	platform_driver_unregister(&jz4740_i2s_driver);
> +}
> +module_exit(jz4740_i2s_exit);
> +
> +MODULE_AUTHOR("Lars-Peter Clausen, <lars@metafoo.de>");
> +MODULE_DESCRIPTION("Ingenic JZ4740 SoC I2S driver");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:jz4740-i2s");
> diff --git a/sound/soc/jz4740/jz4740-i2s.h b/sound/soc/jz4740/jz4740-i2s.h
> new file mode 100644
> index 0000000..da22ed8
> --- /dev/null
> +++ b/sound/soc/jz4740/jz4740-i2s.h
> @@ -0,0 +1,18 @@
> +/*
> + * 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.
> + */
> +
> +#ifndef _JZ4740_I2S_H
> +#define _JZ4740_I2S_H
> +
> +/* I2S clock source */
> +#define JZ4740_I2S_CLKSRC_EXT 0
> +#define JZ4740_I2S_CLKSRC_PLL 1
> +
> +#define JZ4740_I2S_BIT_CLK		0
> +
> +extern struct snd_soc_dai jz4740_i2s_dai;
> +
> +#endif
> diff --git a/sound/soc/jz4740/jz4740-pcm.c b/sound/soc/jz4740/jz4740-pcm.c
> new file mode 100644
> index 0000000..fd1c203
> --- /dev/null
> +++ b/sound/soc/jz4740/jz4740-pcm.c
> @@ -0,0 +1,350 @@
> +/*
> + *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
> + *
> + *  This program is free software; you can redistribute	 it and/or modify it
> + *  under  the terms of	 the GNU General  Public License as published by the
> + *  Free Software Foundation;  either version 2 of the	License, or (at your
> + *  option) any later version.
> + *
> + *  You should have received a copy of the  GNU General Public License along
> + *  with this program; if not, write  to the Free Software Foundation, Inc.,
> + *  675 Mass Ave, Cambridge, MA 02139, USA.
> + *
> + */
> +
> +#include <linux/init.h>
> +#include <linux/interrupt.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/slab.h>
> +
> +#include <linux/dma-mapping.h>
> +
> +#include <sound/core.h>
> +#include <sound/pcm.h>
> +#include <sound/pcm_params.h>
> +#include <sound/soc.h>
> +
> +#include <asm/mach-jz4740/dma.h>
> +#include "jz4740-pcm.h"
> +
> +struct jz4740_runtime_data {
> +	unsigned int dma_period;
> +	dma_addr_t dma_start;
> +	dma_addr_t dma_pos;
> +	dma_addr_t dma_end;
> +
> +	struct jz4740_dma_chan *dma;
> +
> +	dma_addr_t fifo_addr;
> +};
> +
> +/* identify hardware playback capabilities */
> +static const struct snd_pcm_hardware jz4740_pcm_hardware = {
> +	.info = SNDRV_PCM_INFO_MMAP |
> +		SNDRV_PCM_INFO_MMAP_VALID |
> +		SNDRV_PCM_INFO_INTERLEAVED |
> +		SNDRV_PCM_INFO_BLOCK_TRANSFER,
> +	.formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S8,
> +
> +	.rates			= SNDRV_PCM_RATE_8000_48000,
> +	.channels_min		= 1,
> +	.channels_max		= 2,
> +	.period_bytes_min	= 16,
> +	.period_bytes_max	= 2 * PAGE_SIZE,
> +	.periods_min		= 2,
> +	.periods_max		= 128,
> +	.buffer_bytes_max	= 128 * 2 * PAGE_SIZE,
> +	.fifo_size		= 32,
> +};
> +
> +static void jz4740_pcm_start_transfer(struct jz4740_runtime_data *prtd, int stream)
> +{
> +	unsigned int count;
> +
> +	if (prtd->dma_pos + prtd->dma_period > prtd->dma_end)
> +		count = prtd->dma_end - prtd->dma_pos;
> +	else
> +		count = prtd->dma_period;
> +
> +	jz4740_dma_disable(prtd->dma);
> +
> +	if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
> +		jz4740_dma_set_src_addr(prtd->dma, prtd->dma_pos);
> +		jz4740_dma_set_dst_addr(prtd->dma, prtd->fifo_addr);
> +	} else {
> +		jz4740_dma_set_src_addr(prtd->dma, prtd->fifo_addr);
> +		jz4740_dma_set_dst_addr(prtd->dma, prtd->dma_pos);
> +	}
> +
> +	jz4740_dma_set_transfer_count(prtd->dma, count);
> +
> +	jz4740_dma_enable(prtd->dma);
> +
> +	prtd->dma_pos += prtd->dma_period;
> +	if (prtd->dma_pos >= prtd->dma_end)
> +		prtd->dma_pos = prtd->dma_start;
> +}
> +
> +static void jz4740_pcm_dma_transfer_done(struct jz4740_dma_chan *dma, int err,
> +	void *dev_id)
> +{
> +	struct snd_pcm_substream *substream = dev_id;
> +	struct snd_pcm_runtime *runtime = substream->runtime;
> +	struct jz4740_runtime_data *prtd = runtime->private_data;
> +
> +	snd_pcm_period_elapsed(substream);
> +
> +	jz4740_pcm_start_transfer(prtd, substream->stream);
> +}
> +
> +static int jz4740_pcm_hw_params(struct snd_pcm_substream *substream,
> +	struct snd_pcm_hw_params *params)
> +{
> +	struct snd_pcm_runtime *runtime = substream->runtime;
> +	struct jz4740_runtime_data *prtd = runtime->private_data;
> +	struct snd_soc_pcm_runtime *rtd = substream->private_data;
> +	struct jz4740_pcm_config *config;
> +
> +	config = snd_soc_dai_get_dma_data(rtd->dai->cpu_dai, substream);
> +	if (!prtd->dma) {
> +		const char *dma_channel_name;
> +		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
> +			dma_channel_name = "PCM Playback";
> +		else
> +			dma_channel_name = "PCM Capture";
> +
> +		prtd->dma = jz4740_dma_request(substream, dma_channel_name);

dma_channel_name variable is not required here. Just use the const char
* directly.

> +	}
> +
> +	if (!prtd->dma)
> +		return -EBUSY;
> +
> +	jz4740_dma_configure(prtd->dma, &config->dma_config);
> +	prtd->fifo_addr = config->fifo_addr;
> +
> +	jz4740_dma_set_complete_cb(prtd->dma, jz4740_pcm_dma_transfer_done);
> +
> +	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
> +	runtime->dma_bytes = params_buffer_bytes(params);
> +
> +	prtd->dma_period = params_period_bytes(params);
> +	prtd->dma_start = runtime->dma_addr;
> +	prtd->dma_pos = prtd->dma_start;
> +	prtd->dma_end = prtd->dma_start + runtime->dma_bytes;
> +
> +	return 0;
> +}
> +
> +static int jz4740_pcm_hw_free(struct snd_pcm_substream *substream)
> +{
> +	struct jz4740_runtime_data *prtd = substream->runtime->private_data;
> +
> +	snd_pcm_set_runtime_buffer(substream, NULL);
> +	if (prtd->dma) {
> +		jz4740_dma_free(prtd->dma);
> +		prtd->dma = NULL;
> +	}
> +
> +	return 0;
> +}
> +
> +static int jz4740_pcm_prepare(struct snd_pcm_substream *substream)
> +{
> +	struct jz4740_runtime_data *prtd = substream->runtime->private_data;
> +	int ret = 0;
> +
> +	if (!prtd->dma)
> +			return 0;
> +
> +	prtd->dma_pos = prtd->dma_start;
> +
> +	return ret;
> +}
> +
> +static int jz4740_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
> +{
> +	struct snd_pcm_runtime *runtime = substream->runtime;
> +	struct jz4740_runtime_data *prtd = runtime->private_data;
> +
No new line.

> +	int ret = 0;
> +
> +	switch (cmd) {
> +	case SNDRV_PCM_TRIGGER_START:
> +	case SNDRV_PCM_TRIGGER_RESUME:
> +	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
> +		jz4740_pcm_start_transfer(prtd, substream->stream);
> +		break;
> +	case SNDRV_PCM_TRIGGER_STOP:
> +	case SNDRV_PCM_TRIGGER_SUSPEND:
> +	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
> +		jz4740_dma_disable(prtd->dma);
> +		break;
> +	default:
> +		ret = -EINVAL;
> +	}
> +
> +	return ret;
> +}
> +
> +static snd_pcm_uframes_t jz4740_pcm_pointer(struct snd_pcm_substream *substream)
> +{
> +	struct snd_pcm_runtime *runtime = substream->runtime;
> +	struct jz4740_runtime_data *prtd = runtime->private_data;
> +	unsigned long count, pos;
> +	snd_pcm_uframes_t offset;
> +	struct jz4740_dma_chan *dma = prtd->dma;
> +
> +	count = jz4740_dma_get_residue(dma);
> +	if (prtd->dma_pos == prtd->dma_start)
> +		pos = prtd->dma_end - prtd->dma_start - count;
> +	else
> +		pos = prtd->dma_pos - prtd->dma_start - count;
> +
> +	offset = bytes_to_frames(runtime, pos);
> +	if (offset >= runtime->buffer_size)
> +		offset = 0;
> +

Could you comment your calculation a little more.

> +	return offset;
> +}
> +
> +static int jz4740_pcm_open(struct snd_pcm_substream *substream)
> +{
> +	struct snd_pcm_runtime *runtime = substream->runtime;
> +	struct jz4740_runtime_data *prtd;
> +
> +	snd_soc_set_runtime_hwparams(substream, &jz4740_pcm_hardware);
> +	prtd = kzalloc(sizeof(struct jz4740_runtime_data), GFP_KERNEL);
> +
> +	if (prtd == NULL)
> +		return -ENOMEM;
> +
> +	runtime->private_data = prtd;
> +	return 0;
> +}
> +
> +static int jz4740_pcm_close(struct snd_pcm_substream *substream)
> +{
> +	struct snd_pcm_runtime *runtime = substream->runtime;
> +	struct jz4740_runtime_data *prtd = runtime->private_data;
> +
> +	kfree(prtd);
> +
> +	return 0;
> +}
> +
> +static int jz4740_pcm_mmap(struct snd_pcm_substream *substream,
> +	struct vm_area_struct *vma)
> +{
> +	return remap_pfn_range(vma, vma->vm_start,
> +			substream->dma_buffer.addr >> PAGE_SHIFT,
> +			vma->vm_end - vma->vm_start, vma->vm_page_prot);
> +}
> +
> +static struct snd_pcm_ops jz4740_pcm_ops = {
> +	.open		= jz4740_pcm_open,
> +	.close		= jz4740_pcm_close,
> +	.ioctl		= snd_pcm_lib_ioctl,
> +	.hw_params	= jz4740_pcm_hw_params,
> +	.hw_free	= jz4740_pcm_hw_free,
> +	.prepare	= jz4740_pcm_prepare,
> +	.trigger	= jz4740_pcm_trigger,
> +	.pointer	= jz4740_pcm_pointer,
> +	.mmap		= jz4740_pcm_mmap,
> +};
> +
> +static int jz4740_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 = jz4740_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_noncoherent(pcm->card->dev, size,
> +					  &buf->addr, GFP_KERNEL);
> +	if (!buf->area)
> +		return -ENOMEM;
> +
> +	buf->bytes = size;
> +
> +	return 0;
> +}
> +
> +static void jz4740_pcm_free(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_noncoherent(pcm->card->dev, buf->bytes,
> +		  buf->area, buf->addr);
> +		buf->area = NULL;
> +	}
> +}
> +
> +static u64 jz4740_pcm_dmamask = DMA_BIT_MASK(32);
> +
> +int jz4740_pcm_new(struct snd_card *card, struct snd_soc_dai *dai,
> +	struct snd_pcm *pcm)
> +{
> +	int ret = 0;
> +
> +	if (!card->dev->dma_mask)
> +		card->dev->dma_mask = &jz4740_pcm_dmamask;
> +
> +	if (!card->dev->coherent_dma_mask)
> +		card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
> +
> +	if (dai->playback.channels_min) {
> +		ret = jz4740_pcm_preallocate_dma_buffer(pcm,
> +			SNDRV_PCM_STREAM_PLAYBACK);
> +		if (ret)
> +			goto err;
> +	}
> +
> +	if (dai->capture.channels_min) {
> +		ret = jz4740_pcm_preallocate_dma_buffer(pcm,
> +			SNDRV_PCM_STREAM_CAPTURE);
> +		if (ret)
> +			goto err;
> +	}
> +
> +err:
> +	return ret;
> +}
> +
> +struct snd_soc_platform jz4740_soc_platform = {
> +		.name		= "jz4740-pcm",
> +		.pcm_ops	= &jz4740_pcm_ops,
> +		.pcm_new	= jz4740_pcm_new,
> +		.pcm_free	= jz4740_pcm_free,
> +};
> +EXPORT_SYMBOL_GPL(jz4740_soc_platform);
> +
> +static int __init jz4740_soc_platform_init(void)
> +{
> +	return snd_soc_register_platform(&jz4740_soc_platform);
> +}
> +module_init(jz4740_soc_platform_init);
> +
> +static void __exit jz4740_soc_platform_exit(void)
> +{
> +	snd_soc_unregister_platform(&jz4740_soc_platform);
> +}
> +module_exit(jz4740_soc_platform_exit);
> +
> +MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
> +MODULE_DESCRIPTION("Ingenic SoC JZ4740 PCM driver");
> +MODULE_LICENSE("GPL");
> diff --git a/sound/soc/jz4740/jz4740-pcm.h b/sound/soc/jz4740/jz4740-pcm.h
> new file mode 100644
> index 0000000..e3f221e
> --- /dev/null
> +++ b/sound/soc/jz4740/jz4740-pcm.h
> @@ -0,0 +1,22 @@
> +/*
> + *
> + * 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.
> + */
> +
> +#ifndef _JZ4740_PCM_H
> +#define _JZ4740_PCM_H
> +
> +#include <linux/dma-mapping.h>
> +#include <asm/mach-jz4740/dma.h>
> +
> +/* platform data */
> +extern struct snd_soc_platform jz4740_soc_platform;
> +
> +struct jz4740_pcm_config {
> +	struct jz4740_dma_config dma_config;
> +	phys_addr_t fifo_addr;
> +};
> +
> +#endif

Thanks

Liam
-- 
Freelance Developer, SlimLogic Ltd
ASoC and Voltage Regulator Maintainer.
http://www.slimlogic.co.uk