sound/soc/img/img-i2s-in.c - kernel/quantenna - Git at Google

 /*
  * IMG I2S input controller driver
  *
  * Copyright (C) 2015 Imagination Technologies Ltd.
  *
  * Author: Damien Horsley <Damien.Horsley@imgtec.com>
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
  * version 2, as published by the Free Software Foundation.
  */

 #include <linux/clk.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/reset.h>

 #include <sound/core.h>
 #include <sound/dmaengine_pcm.h>
 #include <sound/initval.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
 #include <sound/soc.h>

 #define IMG_I2S_IN_RX_FIFO			0x0

 #define IMG_I2S_IN_CTL				0x4
 #define IMG_I2S_IN_CTL_ACTIVE_CHAN_MASK		0xfffffffc
 #define IMG_I2S_IN_CTL_ACTIVE_CH_SHIFT		2
 #define IMG_I2S_IN_CTL_16PACK_MASK		BIT(1)
 #define IMG_I2S_IN_CTL_ME_MASK			BIT(0)

 #define IMG_I2S_IN_CH_CTL			0x4
 #define IMG_I2S_IN_CH_CTL_CCDEL_MASK		0x38000
 #define IMG_I2S_IN_CH_CTL_CCDEL_SHIFT		15
 #define IMG_I2S_IN_CH_CTL_FEN_MASK		BIT(14)
 #define IMG_I2S_IN_CH_CTL_FMODE_MASK		BIT(13)
 #define IMG_I2S_IN_CH_CTL_16PACK_MASK		BIT(12)
 #define IMG_I2S_IN_CH_CTL_JUST_MASK		BIT(10)
 #define IMG_I2S_IN_CH_CTL_PACKH_MASK		BIT(9)
 #define IMG_I2S_IN_CH_CTL_CLK_TRANS_MASK	BIT(8)
 #define IMG_I2S_IN_CH_CTL_BLKP_MASK		BIT(7)
 #define IMG_I2S_IN_CH_CTL_FIFO_FLUSH_MASK	BIT(6)
 #define IMG_I2S_IN_CH_CTL_LRD_MASK		BIT(3)
 #define IMG_I2S_IN_CH_CTL_FW_MASK		BIT(2)
 #define IMG_I2S_IN_CH_CTL_SW_MASK		BIT(1)
 #define IMG_I2S_IN_CH_CTL_ME_MASK		BIT(0)

 #define IMG_I2S_IN_CH_STRIDE			0x20

 struct img_i2s_in {
 	void __iomem *base;
 	struct clk *clk_sys;
 	struct snd_dmaengine_dai_dma_data dma_data;
 	struct device *dev;
 	unsigned int max_i2s_chan;
 	void __iomem *channel_base;
 	unsigned int active_channels;
 	struct snd_soc_dai_driver dai_driver;
 };

 static inline void img_i2s_in_writel(struct img_i2s_in *i2s, u32 val, u32 reg)
 {
 	writel(val, i2s->base + reg);
 }

 static inline u32 img_i2s_in_readl(struct img_i2s_in *i2s, u32 reg)
 {
 	return readl(i2s->base + reg);
 }

 static inline void img_i2s_in_ch_writel(struct img_i2s_in *i2s, u32 chan,
 					u32 val, u32 reg)
 {
 	writel(val, i2s->channel_base + (chan * IMG_I2S_IN_CH_STRIDE) + reg);
 }

 static inline u32 img_i2s_in_ch_readl(struct img_i2s_in *i2s, u32 chan,
 					u32 reg)
 {
 	return readl(i2s->channel_base + (chan * IMG_I2S_IN_CH_STRIDE) + reg);
 }

 static inline void img_i2s_in_ch_disable(struct img_i2s_in *i2s, u32 chan)
 {
 	u32 reg;

 	reg = img_i2s_in_ch_readl(i2s, chan, IMG_I2S_IN_CH_CTL);
 	reg &= ~IMG_I2S_IN_CH_CTL_ME_MASK;
 	img_i2s_in_ch_writel(i2s, chan, reg, IMG_I2S_IN_CH_CTL);
 }

 static inline void img_i2s_in_ch_enable(struct img_i2s_in *i2s, u32 chan)
 {
 	u32 reg;

 	reg = img_i2s_in_ch_readl(i2s, chan, IMG_I2S_IN_CH_CTL);
 	reg |= IMG_I2S_IN_CH_CTL_ME_MASK;
 	img_i2s_in_ch_writel(i2s, chan, reg, IMG_I2S_IN_CH_CTL);
 }

 static inline void img_i2s_in_disable(struct img_i2s_in *i2s)
 {
 	u32 reg;

 	reg = img_i2s_in_readl(i2s, IMG_I2S_IN_CTL);
 	reg &= ~IMG_I2S_IN_CTL_ME_MASK;
 	img_i2s_in_writel(i2s, reg, IMG_I2S_IN_CTL);
 }

 static inline void img_i2s_in_enable(struct img_i2s_in *i2s)
 {
 	u32 reg;

 	reg = img_i2s_in_readl(i2s, IMG_I2S_IN_CTL);
 	reg |= IMG_I2S_IN_CTL_ME_MASK;
 	img_i2s_in_writel(i2s, reg, IMG_I2S_IN_CTL);
 }

 static inline void img_i2s_in_flush(struct img_i2s_in *i2s)
 {
 	int i;
 	u32 reg;

 	for (i = 0; i < i2s->active_channels; i++) {
 		reg = img_i2s_in_ch_readl(i2s, i, IMG_I2S_IN_CH_CTL);
 		reg |= IMG_I2S_IN_CH_CTL_FIFO_FLUSH_MASK;
 		img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
 		reg &= ~IMG_I2S_IN_CH_CTL_FIFO_FLUSH_MASK;
 		img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
 	}
 }

 static int img_i2s_in_trigger(struct snd_pcm_substream *substream, int cmd,
 	struct snd_soc_dai *dai)
 {
 	struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai);

 	switch (cmd) {
 	case SNDRV_PCM_TRIGGER_START:
 	case SNDRV_PCM_TRIGGER_RESUME:
 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 		img_i2s_in_enable(i2s);
 		break;

 	case SNDRV_PCM_TRIGGER_STOP:
 	case SNDRV_PCM_TRIGGER_SUSPEND:
 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 		img_i2s_in_disable(i2s);
 		break;
 	default:
 		return -EINVAL;
 	}

 	return 0;
 }

 static int img_i2s_in_check_rate(struct img_i2s_in *i2s,
 		unsigned int sample_rate, unsigned int frame_size,
 		unsigned int *bclk_filter_enable,
 		unsigned int *bclk_filter_value)
 {
 	unsigned int bclk_freq, cur_freq;

 	bclk_freq = sample_rate * frame_size;

 	cur_freq = clk_get_rate(i2s->clk_sys);

 	if (cur_freq >= bclk_freq * 8) {
 		*bclk_filter_enable = 1;
 		*bclk_filter_value = 0;
 	} else if (cur_freq >= bclk_freq * 7) {
 		*bclk_filter_enable = 1;
 		*bclk_filter_value = 1;
 	} else if (cur_freq >= bclk_freq * 6) {
 		*bclk_filter_enable = 0;
 		*bclk_filter_value = 0;
 	} else {
 		dev_err(i2s->dev,
 			"Sys clock rate %u insufficient for sample rate %u\n",
 			cur_freq, sample_rate);
 		return -EINVAL;
 	}

 	return 0;
 }

 static int img_i2s_in_hw_params(struct snd_pcm_substream *substream,
 	struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
 {
 	struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai);
 	unsigned int rate, channels, i2s_channels, frame_size;
 	unsigned int bclk_filter_enable, bclk_filter_value;
 	int i, ret = 0;
 	u32 reg, control_mask, chan_control_mask;
 	u32 control_set = 0, chan_control_set = 0;
 	snd_pcm_format_t format;

 	rate = params_rate(params);
 	format = params_format(params);
 	channels = params_channels(params);
 	i2s_channels = channels / 2;

 	switch (format) {
 	case SNDRV_PCM_FORMAT_S32_LE:
 		frame_size = 64;
 		chan_control_set |= IMG_I2S_IN_CH_CTL_SW_MASK;
 		chan_control_set |= IMG_I2S_IN_CH_CTL_FW_MASK;
 		chan_control_set |= IMG_I2S_IN_CH_CTL_PACKH_MASK;
 		break;
 	case SNDRV_PCM_FORMAT_S24_LE:
 		frame_size = 64;
 		chan_control_set |= IMG_I2S_IN_CH_CTL_SW_MASK;
 		chan_control_set |= IMG_I2S_IN_CH_CTL_FW_MASK;
 		break;
 	case SNDRV_PCM_FORMAT_S16_LE:
 		frame_size = 32;
 		control_set |= IMG_I2S_IN_CTL_16PACK_MASK;
 		chan_control_set |= IMG_I2S_IN_CH_CTL_16PACK_MASK;
 		break;
 	default:
 		return -EINVAL;
 	}

 	if ((channels < 2) ||
 	    (channels > (i2s->max_i2s_chan * 2)) ||
 	    (channels % 2))
 		return -EINVAL;

 	control_set |= ((i2s_channels - 1) << IMG_I2S_IN_CTL_ACTIVE_CH_SHIFT);

 	ret = img_i2s_in_check_rate(i2s, rate, frame_size,
 			&bclk_filter_enable, &bclk_filter_value);
 	if (ret < 0)
 		return ret;

 	if (bclk_filter_enable)
 		chan_control_set |= IMG_I2S_IN_CH_CTL_FEN_MASK;

 	if (bclk_filter_value)
 		chan_control_set |= IMG_I2S_IN_CH_CTL_FMODE_MASK;

 	control_mask = IMG_I2S_IN_CTL_16PACK_MASK |
 		       IMG_I2S_IN_CTL_ACTIVE_CHAN_MASK;

 	chan_control_mask = IMG_I2S_IN_CH_CTL_16PACK_MASK |
 			    IMG_I2S_IN_CH_CTL_FEN_MASK |
 			    IMG_I2S_IN_CH_CTL_FMODE_MASK |
 			    IMG_I2S_IN_CH_CTL_SW_MASK |
 			    IMG_I2S_IN_CH_CTL_FW_MASK |
 			    IMG_I2S_IN_CH_CTL_PACKH_MASK;

 	reg = img_i2s_in_readl(i2s, IMG_I2S_IN_CTL);
 	reg = (reg & ~control_mask) | control_set;
 	img_i2s_in_writel(i2s, reg, IMG_I2S_IN_CTL);

 	for (i = 0; i < i2s->active_channels; i++)
 		img_i2s_in_ch_disable(i2s, i);

 	for (i = 0; i < i2s->max_i2s_chan; i++) {
 		reg = img_i2s_in_ch_readl(i2s, i, IMG_I2S_IN_CH_CTL);
 		reg = (reg & ~chan_control_mask) | chan_control_set;
 		img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
 	}

 	i2s->active_channels = i2s_channels;

 	img_i2s_in_flush(i2s);

 	for (i = 0; i < i2s->active_channels; i++)
 		img_i2s_in_ch_enable(i2s, i);

 	return 0;
 }

 static int img_i2s_in_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
 {
 	struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai);
 	int i;
 	u32 chan_control_mask, lrd_set = 0, blkp_set = 0, chan_control_set = 0;
 	u32 reg;

 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
 	case SND_SOC_DAIFMT_NB_NF:
 		lrd_set |= IMG_I2S_IN_CH_CTL_LRD_MASK;
 		break;
 	case SND_SOC_DAIFMT_NB_IF:
 		break;
 	case SND_SOC_DAIFMT_IB_NF:
 		lrd_set |= IMG_I2S_IN_CH_CTL_LRD_MASK;
 		blkp_set |= IMG_I2S_IN_CH_CTL_BLKP_MASK;
 		break;
 	case SND_SOC_DAIFMT_IB_IF:
 		blkp_set |= IMG_I2S_IN_CH_CTL_BLKP_MASK;
 		break;
 	default:
 		return -EINVAL;
 	}

 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
 	case SND_SOC_DAIFMT_I2S:
 		chan_control_set |= IMG_I2S_IN_CH_CTL_CLK_TRANS_MASK;
 		break;
 	case SND_SOC_DAIFMT_LEFT_J:
 		break;
 	default:
 		return -EINVAL;
 	}

 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
 	case SND_SOC_DAIFMT_CBM_CFM:
 		break;
 	default:
 		return -EINVAL;
 	}

 	chan_control_mask = IMG_I2S_IN_CH_CTL_CLK_TRANS_MASK;

 	for (i = 0; i < i2s->active_channels; i++)
 		img_i2s_in_ch_disable(i2s, i);

 	/*
 	 * BLKP and LRD must be set during separate register writes
 	 */
 	for (i = 0; i < i2s->max_i2s_chan; i++) {
 		reg = img_i2s_in_ch_readl(i2s, i, IMG_I2S_IN_CH_CTL);
 		reg = (reg & ~chan_control_mask) | chan_control_set;
 		img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
 		reg = (reg & ~IMG_I2S_IN_CH_CTL_BLKP_MASK) | blkp_set;
 		img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
 		reg = (reg & ~IMG_I2S_IN_CH_CTL_LRD_MASK) | lrd_set;
 		img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
 	}

 	for (i = 0; i < i2s->active_channels; i++)
 		img_i2s_in_ch_enable(i2s, i);

 	return 0;
 }

 static const struct snd_soc_dai_ops img_i2s_in_dai_ops = {
 	.trigger = img_i2s_in_trigger,
 	.hw_params = img_i2s_in_hw_params,
 	.set_fmt = img_i2s_in_set_fmt
 };

 static int img_i2s_in_dai_probe(struct snd_soc_dai *dai)
 {
 	struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai);

 	snd_soc_dai_init_dma_data(dai, NULL, &i2s->dma_data);

 	return 0;
 }

 static const struct snd_soc_component_driver img_i2s_in_component = {
 	.name = "img-i2s-in"
 };

 static int img_i2s_in_dma_prepare_slave_config(struct snd_pcm_substream *st,
 	struct snd_pcm_hw_params *params, struct dma_slave_config *sc)
 {
 	unsigned int i2s_channels = params_channels(params) / 2;
 	struct snd_soc_pcm_runtime *rtd = st->private_data;
 	struct snd_dmaengine_dai_dma_data *dma_data;
 	int ret;

 	dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, st);

 	ret = snd_hwparams_to_dma_slave_config(st, params, sc);
 	if (ret)
 		return ret;

 	sc->src_addr = dma_data->addr;
 	sc->src_addr_width = dma_data->addr_width;
 	sc->src_maxburst = 4 * i2s_channels;

 	return 0;
 }

 static const struct snd_dmaengine_pcm_config img_i2s_in_dma_config = {
 	.prepare_slave_config = img_i2s_in_dma_prepare_slave_config
 };

 static int img_i2s_in_probe(struct platform_device *pdev)
 {
 	struct img_i2s_in *i2s;
 	struct resource *res;
 	void __iomem *base;
 	int ret, i;
 	struct reset_control *rst;
 	unsigned int max_i2s_chan_pow_2;
 	struct device *dev = &pdev->dev;

 	i2s = devm_kzalloc(dev, sizeof(*i2s), GFP_KERNEL);
 	if (!i2s)
 		return -ENOMEM;

 	platform_set_drvdata(pdev, i2s);

 	i2s->dev = dev;

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	base = devm_ioremap_resource(dev, res);
 	if (IS_ERR(base))
 		return PTR_ERR(base);

 	i2s->base = base;

 	if (of_property_read_u32(pdev->dev.of_node, "img,i2s-channels",
 			&i2s->max_i2s_chan)) {
 		dev_err(dev, "No img,i2s-channels property\n");
 		return -EINVAL;
 	}

 	max_i2s_chan_pow_2 = 1 << get_count_order(i2s->max_i2s_chan);

 	i2s->channel_base = base + (max_i2s_chan_pow_2 * 0x20);

 	i2s->clk_sys = devm_clk_get(dev, "sys");
 	if (IS_ERR(i2s->clk_sys)) {
 		if (PTR_ERR(i2s->clk_sys) != -EPROBE_DEFER)
 			dev_err(dev, "Failed to acquire clock 'sys'\n");
 		return PTR_ERR(i2s->clk_sys);
 	}

 	ret = clk_prepare_enable(i2s->clk_sys);
 	if (ret)
 		return ret;

 	i2s->active_channels = 1;
 	i2s->dma_data.addr = res->start + IMG_I2S_IN_RX_FIFO;
 	i2s->dma_data.addr_width = 4;

 	i2s->dai_driver.probe = img_i2s_in_dai_probe;
 	i2s->dai_driver.capture.channels_min = 2;
 	i2s->dai_driver.capture.channels_max = i2s->max_i2s_chan * 2;
 	i2s->dai_driver.capture.rates = SNDRV_PCM_RATE_8000_192000;
 	i2s->dai_driver.capture.formats = SNDRV_PCM_FMTBIT_S32_LE |
 		SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S16_LE;
 	i2s->dai_driver.ops = &img_i2s_in_dai_ops;

 	rst = devm_reset_control_get(dev, "rst");
 	if (IS_ERR(rst)) {
 		if (PTR_ERR(rst) == -EPROBE_DEFER) {
 			ret = -EPROBE_DEFER;
 			goto err_clk_disable;
 		}

 		dev_dbg(dev, "No top level reset found\n");

 		img_i2s_in_disable(i2s);

 		for (i = 0; i < i2s->max_i2s_chan; i++)
 			img_i2s_in_ch_disable(i2s, i);
 	} else {
 		reset_control_assert(rst);
 		reset_control_deassert(rst);
 	}

 	img_i2s_in_writel(i2s, 0, IMG_I2S_IN_CTL);

 	for (i = 0; i < i2s->max_i2s_chan; i++)
 		img_i2s_in_ch_writel(i2s, i,
 			(4 << IMG_I2S_IN_CH_CTL_CCDEL_SHIFT) |
 			IMG_I2S_IN_CH_CTL_JUST_MASK |
 			IMG_I2S_IN_CH_CTL_FW_MASK, IMG_I2S_IN_CH_CTL);

 	ret = devm_snd_soc_register_component(dev, &img_i2s_in_component,
 						&i2s->dai_driver, 1);
 	if (ret)
 		goto err_clk_disable;

 	ret = devm_snd_dmaengine_pcm_register(dev, &img_i2s_in_dma_config, 0);
 	if (ret)
 		goto err_clk_disable;

 	return 0;

 err_clk_disable:
 	clk_disable_unprepare(i2s->clk_sys);

 	return ret;
 }

 static int img_i2s_in_dev_remove(struct platform_device *pdev)
 {
 	struct img_i2s_in *i2s = platform_get_drvdata(pdev);

 	clk_disable_unprepare(i2s->clk_sys);

 	return 0;
 }

 static const struct of_device_id img_i2s_in_of_match[] = {
 	{ .compatible = "img,i2s-in" },
 	{}
 };
 MODULE_DEVICE_TABLE(of, img_i2s_in_of_match);

 static struct platform_driver img_i2s_in_driver = {
 	.driver = {
 		.name = "img-i2s-in",
 		.of_match_table = img_i2s_in_of_match
 	},
 	.probe = img_i2s_in_probe,
 	.remove = img_i2s_in_dev_remove
 };
 module_platform_driver(img_i2s_in_driver);

 MODULE_AUTHOR("Damien Horsley <Damien.Horsley@imgtec.com>");
 MODULE_DESCRIPTION("IMG I2S Input Driver");
 MODULE_LICENSE("GPL v2");
	/*
	* IMG I2S input controller driver
	*
	* Copyright (C) 2015 Imagination Technologies Ltd.
	*
	* Author: Damien Horsley <Damien.Horsley@imgtec.com>
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms and conditions of the GNU General Public License,
	* version 2, as published by the Free Software Foundation.
	*/

	#include <linux/clk.h>
	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/platform_device.h>
	#include <linux/reset.h>

	#include <sound/core.h>
	#include <sound/dmaengine_pcm.h>
	#include <sound/initval.h>
	#include <sound/pcm.h>
	#include <sound/pcm_params.h>
	#include <sound/soc.h>

	#define IMG_I2S_IN_RX_FIFO 0x0

	#define IMG_I2S_IN_CTL 0x4
	#define IMG_I2S_IN_CTL_ACTIVE_CHAN_MASK 0xfffffffc
	#define IMG_I2S_IN_CTL_ACTIVE_CH_SHIFT 2
	#define IMG_I2S_IN_CTL_16PACK_MASK BIT(1)
	#define IMG_I2S_IN_CTL_ME_MASK BIT(0)

	#define IMG_I2S_IN_CH_CTL 0x4
	#define IMG_I2S_IN_CH_CTL_CCDEL_MASK 0x38000
	#define IMG_I2S_IN_CH_CTL_CCDEL_SHIFT 15
	#define IMG_I2S_IN_CH_CTL_FEN_MASK BIT(14)
	#define IMG_I2S_IN_CH_CTL_FMODE_MASK BIT(13)
	#define IMG_I2S_IN_CH_CTL_16PACK_MASK BIT(12)
	#define IMG_I2S_IN_CH_CTL_JUST_MASK BIT(10)
	#define IMG_I2S_IN_CH_CTL_PACKH_MASK BIT(9)
	#define IMG_I2S_IN_CH_CTL_CLK_TRANS_MASK BIT(8)
	#define IMG_I2S_IN_CH_CTL_BLKP_MASK BIT(7)
	#define IMG_I2S_IN_CH_CTL_FIFO_FLUSH_MASK BIT(6)
	#define IMG_I2S_IN_CH_CTL_LRD_MASK BIT(3)
	#define IMG_I2S_IN_CH_CTL_FW_MASK BIT(2)
	#define IMG_I2S_IN_CH_CTL_SW_MASK BIT(1)
	#define IMG_I2S_IN_CH_CTL_ME_MASK BIT(0)

	#define IMG_I2S_IN_CH_STRIDE 0x20

	struct img_i2s_in {
	void __iomem *base;
	struct clk *clk_sys;
	struct snd_dmaengine_dai_dma_data dma_data;
	struct device *dev;
	unsigned int max_i2s_chan;
	void __iomem *channel_base;
	unsigned int active_channels;
	struct snd_soc_dai_driver dai_driver;
	};

	static inline void img_i2s_in_writel(struct img_i2s_in *i2s, u32 val, u32 reg)
	{
	writel(val, i2s->base + reg);
	}

	static inline u32 img_i2s_in_readl(struct img_i2s_in *i2s, u32 reg)
	{
	return readl(i2s->base + reg);
	}

	static inline void img_i2s_in_ch_writel(struct img_i2s_in *i2s, u32 chan,
	u32 val, u32 reg)
	{
	writel(val, i2s->channel_base + (chan * IMG_I2S_IN_CH_STRIDE) + reg);
	}

	static inline u32 img_i2s_in_ch_readl(struct img_i2s_in *i2s, u32 chan,
	u32 reg)
	{
	return readl(i2s->channel_base + (chan * IMG_I2S_IN_CH_STRIDE) + reg);
	}

	static inline void img_i2s_in_ch_disable(struct img_i2s_in *i2s, u32 chan)
	{
	u32 reg;

	reg = img_i2s_in_ch_readl(i2s, chan, IMG_I2S_IN_CH_CTL);
	reg &= ~IMG_I2S_IN_CH_CTL_ME_MASK;
	img_i2s_in_ch_writel(i2s, chan, reg, IMG_I2S_IN_CH_CTL);
	}

	static inline void img_i2s_in_ch_enable(struct img_i2s_in *i2s, u32 chan)
	{
	u32 reg;

	reg = img_i2s_in_ch_readl(i2s, chan, IMG_I2S_IN_CH_CTL);
	reg \|= IMG_I2S_IN_CH_CTL_ME_MASK;
	img_i2s_in_ch_writel(i2s, chan, reg, IMG_I2S_IN_CH_CTL);
	}

	static inline void img_i2s_in_disable(struct img_i2s_in *i2s)
	{
	u32 reg;

	reg = img_i2s_in_readl(i2s, IMG_I2S_IN_CTL);
	reg &= ~IMG_I2S_IN_CTL_ME_MASK;
	img_i2s_in_writel(i2s, reg, IMG_I2S_IN_CTL);
	}

	static inline void img_i2s_in_enable(struct img_i2s_in *i2s)
	{
	u32 reg;

	reg = img_i2s_in_readl(i2s, IMG_I2S_IN_CTL);
	reg \|= IMG_I2S_IN_CTL_ME_MASK;
	img_i2s_in_writel(i2s, reg, IMG_I2S_IN_CTL);
	}

	static inline void img_i2s_in_flush(struct img_i2s_in *i2s)
	{
	int i;
	u32 reg;

	for (i = 0; i < i2s->active_channels; i++) {
	reg = img_i2s_in_ch_readl(i2s, i, IMG_I2S_IN_CH_CTL);
	reg \|= IMG_I2S_IN_CH_CTL_FIFO_FLUSH_MASK;
	img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
	reg &= ~IMG_I2S_IN_CH_CTL_FIFO_FLUSH_MASK;
	img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
	}
	}

	static int img_i2s_in_trigger(struct snd_pcm_substream *substream, int cmd,
	struct snd_soc_dai *dai)
	{
	struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai);

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
	img_i2s_in_enable(i2s);
	break;

	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
	img_i2s_in_disable(i2s);
	break;
	default:
	return -EINVAL;
	}

	return 0;
	}

	static int img_i2s_in_check_rate(struct img_i2s_in *i2s,
	unsigned int sample_rate, unsigned int frame_size,
	unsigned int *bclk_filter_enable,
	unsigned int *bclk_filter_value)
	{
	unsigned int bclk_freq, cur_freq;

	bclk_freq = sample_rate * frame_size;

	cur_freq = clk_get_rate(i2s->clk_sys);

	if (cur_freq >= bclk_freq * 8) {
	*bclk_filter_enable = 1;
	*bclk_filter_value = 0;
	} else if (cur_freq >= bclk_freq * 7) {
	*bclk_filter_enable = 1;
	*bclk_filter_value = 1;
	} else if (cur_freq >= bclk_freq * 6) {
	*bclk_filter_enable = 0;
	*bclk_filter_value = 0;
	} else {
	dev_err(i2s->dev,
	"Sys clock rate %u insufficient for sample rate %u\n",
	cur_freq, sample_rate);
	return -EINVAL;
	}

	return 0;
	}

	static int img_i2s_in_hw_params(struct snd_pcm_substream *substream,
	struct snd_pcm_hw_params params, struct snd_soc_dai dai)
	{
	struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai);
	unsigned int rate, channels, i2s_channels, frame_size;
	unsigned int bclk_filter_enable, bclk_filter_value;
	int i, ret = 0;
	u32 reg, control_mask, chan_control_mask;
	u32 control_set = 0, chan_control_set = 0;
	snd_pcm_format_t format;

	rate = params_rate(params);
	format = params_format(params);
	channels = params_channels(params);
	i2s_channels = channels / 2;

	switch (format) {
	case SNDRV_PCM_FORMAT_S32_LE:
	frame_size = 64;
	chan_control_set \|= IMG_I2S_IN_CH_CTL_SW_MASK;
	chan_control_set \|= IMG_I2S_IN_CH_CTL_FW_MASK;
	chan_control_set \|= IMG_I2S_IN_CH_CTL_PACKH_MASK;
	break;
	case SNDRV_PCM_FORMAT_S24_LE:
	frame_size = 64;
	chan_control_set \|= IMG_I2S_IN_CH_CTL_SW_MASK;
	chan_control_set \|= IMG_I2S_IN_CH_CTL_FW_MASK;
	break;
	case SNDRV_PCM_FORMAT_S16_LE:
	frame_size = 32;
	control_set \|= IMG_I2S_IN_CTL_16PACK_MASK;
	chan_control_set \|= IMG_I2S_IN_CH_CTL_16PACK_MASK;
	break;
	default:
	return -EINVAL;
	}

	if ((channels < 2) \|\|
	(channels > (i2s->max_i2s_chan * 2)) \|\|
	(channels % 2))
	return -EINVAL;

	control_set \|= ((i2s_channels - 1) << IMG_I2S_IN_CTL_ACTIVE_CH_SHIFT);

	ret = img_i2s_in_check_rate(i2s, rate, frame_size,
	&bclk_filter_enable, &bclk_filter_value);
	if (ret < 0)
	return ret;

	if (bclk_filter_enable)
	chan_control_set \|= IMG_I2S_IN_CH_CTL_FEN_MASK;

	if (bclk_filter_value)
	chan_control_set \|= IMG_I2S_IN_CH_CTL_FMODE_MASK;

	control_mask = IMG_I2S_IN_CTL_16PACK_MASK \|
	IMG_I2S_IN_CTL_ACTIVE_CHAN_MASK;

	chan_control_mask = IMG_I2S_IN_CH_CTL_16PACK_MASK \|
	IMG_I2S_IN_CH_CTL_FEN_MASK \|
	IMG_I2S_IN_CH_CTL_FMODE_MASK \|
	IMG_I2S_IN_CH_CTL_SW_MASK \|
	IMG_I2S_IN_CH_CTL_FW_MASK \|
	IMG_I2S_IN_CH_CTL_PACKH_MASK;

	reg = img_i2s_in_readl(i2s, IMG_I2S_IN_CTL);
	reg = (reg & ~control_mask) \| control_set;
	img_i2s_in_writel(i2s, reg, IMG_I2S_IN_CTL);

	for (i = 0; i < i2s->active_channels; i++)
	img_i2s_in_ch_disable(i2s, i);

	for (i = 0; i < i2s->max_i2s_chan; i++) {
	reg = img_i2s_in_ch_readl(i2s, i, IMG_I2S_IN_CH_CTL);
	reg = (reg & ~chan_control_mask) \| chan_control_set;
	img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
	}

	i2s->active_channels = i2s_channels;

	img_i2s_in_flush(i2s);

	for (i = 0; i < i2s->active_channels; i++)
	img_i2s_in_ch_enable(i2s, i);

	return 0;
	}

	static int img_i2s_in_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
	{
	struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai);
	int i;
	u32 chan_control_mask, lrd_set = 0, blkp_set = 0, chan_control_set = 0;
	u32 reg;

	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
	case SND_SOC_DAIFMT_NB_NF:
	lrd_set \|= IMG_I2S_IN_CH_CTL_LRD_MASK;
	break;
	case SND_SOC_DAIFMT_NB_IF:
	break;
	case SND_SOC_DAIFMT_IB_NF:
	lrd_set \|= IMG_I2S_IN_CH_CTL_LRD_MASK;
	blkp_set \|= IMG_I2S_IN_CH_CTL_BLKP_MASK;
	break;
	case SND_SOC_DAIFMT_IB_IF:
	blkp_set \|= IMG_I2S_IN_CH_CTL_BLKP_MASK;
	break;
	default:
	return -EINVAL;
	}

	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
	case SND_SOC_DAIFMT_I2S:
	chan_control_set \|= IMG_I2S_IN_CH_CTL_CLK_TRANS_MASK;
	break;
	case SND_SOC_DAIFMT_LEFT_J:
	break;
	default:
	return -EINVAL;
	}

	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
	case SND_SOC_DAIFMT_CBM_CFM:
	break;
	default:
	return -EINVAL;
	}

	chan_control_mask = IMG_I2S_IN_CH_CTL_CLK_TRANS_MASK;

	for (i = 0; i < i2s->active_channels; i++)
	img_i2s_in_ch_disable(i2s, i);

	/*
	* BLKP and LRD must be set during separate register writes
	*/
	for (i = 0; i < i2s->max_i2s_chan; i++) {
	reg = img_i2s_in_ch_readl(i2s, i, IMG_I2S_IN_CH_CTL);
	reg = (reg & ~chan_control_mask) \| chan_control_set;
	img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
	reg = (reg & ~IMG_I2S_IN_CH_CTL_BLKP_MASK) \| blkp_set;
	img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
	reg = (reg & ~IMG_I2S_IN_CH_CTL_LRD_MASK) \| lrd_set;
	img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
	}

	for (i = 0; i < i2s->active_channels; i++)
	img_i2s_in_ch_enable(i2s, i);

	return 0;
	}

	static const struct snd_soc_dai_ops img_i2s_in_dai_ops = {
	.trigger = img_i2s_in_trigger,
	.hw_params = img_i2s_in_hw_params,
	.set_fmt = img_i2s_in_set_fmt
	};

	static int img_i2s_in_dai_probe(struct snd_soc_dai *dai)
	{
	struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai);

	snd_soc_dai_init_dma_data(dai, NULL, &i2s->dma_data);

	return 0;
	}

	static const struct snd_soc_component_driver img_i2s_in_component = {
	.name = "img-i2s-in"
	};

	static int img_i2s_in_dma_prepare_slave_config(struct snd_pcm_substream *st,
	struct snd_pcm_hw_params params, struct dma_slave_config sc)
	{
	unsigned int i2s_channels = params_channels(params) / 2;
	struct snd_soc_pcm_runtime *rtd = st->private_data;
	struct snd_dmaengine_dai_dma_data *dma_data;
	int ret;

	dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, st);

	ret = snd_hwparams_to_dma_slave_config(st, params, sc);
	if (ret)
	return ret;

	sc->src_addr = dma_data->addr;
	sc->src_addr_width = dma_data->addr_width;
	sc->src_maxburst = 4 * i2s_channels;

	return 0;
	}

	static const struct snd_dmaengine_pcm_config img_i2s_in_dma_config = {
	.prepare_slave_config = img_i2s_in_dma_prepare_slave_config
	};

	static int img_i2s_in_probe(struct platform_device *pdev)
	{
	struct img_i2s_in *i2s;
	struct resource *res;
	void __iomem *base;
	int ret, i;
	struct reset_control *rst;
	unsigned int max_i2s_chan_pow_2;
	struct device *dev = &pdev->dev;

	i2s = devm_kzalloc(dev, sizeof(*i2s), GFP_KERNEL);
	if (!i2s)
	return -ENOMEM;

	platform_set_drvdata(pdev, i2s);

	i2s->dev = dev;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	base = devm_ioremap_resource(dev, res);
	if (IS_ERR(base))
	return PTR_ERR(base);

	i2s->base = base;

	if (of_property_read_u32(pdev->dev.of_node, "img,i2s-channels",
	&i2s->max_i2s_chan)) {
	dev_err(dev, "No img,i2s-channels property\n");
	return -EINVAL;
	}

	max_i2s_chan_pow_2 = 1 << get_count_order(i2s->max_i2s_chan);

	i2s->channel_base = base + (max_i2s_chan_pow_2 * 0x20);

	i2s->clk_sys = devm_clk_get(dev, "sys");
	if (IS_ERR(i2s->clk_sys)) {
	if (PTR_ERR(i2s->clk_sys) != -EPROBE_DEFER)
	dev_err(dev, "Failed to acquire clock 'sys'\n");
	return PTR_ERR(i2s->clk_sys);
	}

	ret = clk_prepare_enable(i2s->clk_sys);
	if (ret)
	return ret;

	i2s->active_channels = 1;
	i2s->dma_data.addr = res->start + IMG_I2S_IN_RX_FIFO;
	i2s->dma_data.addr_width = 4;

	i2s->dai_driver.probe = img_i2s_in_dai_probe;
	i2s->dai_driver.capture.channels_min = 2;
	i2s->dai_driver.capture.channels_max = i2s->max_i2s_chan * 2;
	i2s->dai_driver.capture.rates = SNDRV_PCM_RATE_8000_192000;
	i2s->dai_driver.capture.formats = SNDRV_PCM_FMTBIT_S32_LE \|
	SNDRV_PCM_FMTBIT_S24_LE \| SNDRV_PCM_FMTBIT_S16_LE;
	i2s->dai_driver.ops = &img_i2s_in_dai_ops;

	rst = devm_reset_control_get(dev, "rst");
	if (IS_ERR(rst)) {
	if (PTR_ERR(rst) == -EPROBE_DEFER) {
	ret = -EPROBE_DEFER;
	goto err_clk_disable;
	}

	dev_dbg(dev, "No top level reset found\n");

	img_i2s_in_disable(i2s);

	for (i = 0; i < i2s->max_i2s_chan; i++)
	img_i2s_in_ch_disable(i2s, i);
	} else {
	reset_control_assert(rst);
	reset_control_deassert(rst);
	}

	img_i2s_in_writel(i2s, 0, IMG_I2S_IN_CTL);

	for (i = 0; i < i2s->max_i2s_chan; i++)
	img_i2s_in_ch_writel(i2s, i,
	(4 << IMG_I2S_IN_CH_CTL_CCDEL_SHIFT) \|
	IMG_I2S_IN_CH_CTL_JUST_MASK \|
	IMG_I2S_IN_CH_CTL_FW_MASK, IMG_I2S_IN_CH_CTL);

	ret = devm_snd_soc_register_component(dev, &img_i2s_in_component,
	&i2s->dai_driver, 1);
	if (ret)
	goto err_clk_disable;

	ret = devm_snd_dmaengine_pcm_register(dev, &img_i2s_in_dma_config, 0);
	if (ret)
	goto err_clk_disable;

	return 0;

	err_clk_disable:
	clk_disable_unprepare(i2s->clk_sys);

	return ret;
	}

	static int img_i2s_in_dev_remove(struct platform_device *pdev)
	{
	struct img_i2s_in *i2s = platform_get_drvdata(pdev);

	clk_disable_unprepare(i2s->clk_sys);

	return 0;
	}

	static const struct of_device_id img_i2s_in_of_match[] = {
	{ .compatible = "img,i2s-in" },
	{}
	};
	MODULE_DEVICE_TABLE(of, img_i2s_in_of_match);

	static struct platform_driver img_i2s_in_driver = {
	.driver = {
	.name = "img-i2s-in",
	.of_match_table = img_i2s_in_of_match
	},
	.probe = img_i2s_in_probe,
	.remove = img_i2s_in_dev_remove
	};
	module_platform_driver(img_i2s_in_driver);

	MODULE_AUTHOR("Damien Horsley <Damien.Horsley@imgtec.com>");
	MODULE_DESCRIPTION("IMG I2S Input Driver");
	MODULE_LICENSE("GPL v2");