sound/soc/qcom/lpass-platform.c - kernel/lockdown - Git at Google

 /*
  * Copyright (c) 2010-2011,2013-2015 The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
  * only 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.
  *
  * lpass-platform.c -- ALSA SoC platform driver for QTi LPASS
  */

 #include <linux/compiler.h>
 #include <linux/device.h>
 #include <linux/dma-mapping.h>
 #include <linux/err.h>
 #include <linux/export.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/io.h>
 #include <linux/platform_device.h>
 #include <sound/memalloc.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
 #include <linux/regmap.h>
 #include <sound/soc.h>
 #include "lpass-lpaif-ipq806x.h"
 #include "lpass.h"

 #define LPASS_PLATFORM_BUFFER_SIZE	(16 * 1024)
 #define LPASS_PLATFORM_PERIODS		2

 static struct snd_pcm_hardware lpass_platform_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 |
 					SNDRV_PCM_FMTBIT_S24 |
 					SNDRV_PCM_FMTBIT_S32,
 	.rates			=	SNDRV_PCM_RATE_8000_192000,
 	.rate_min		=	8000,
 	.rate_max		=	192000,
 	.channels_min		=	1,
 	.channels_max		=	8,
 	.buffer_bytes_max	=	LPASS_PLATFORM_BUFFER_SIZE,
 	.period_bytes_max	=	LPASS_PLATFORM_BUFFER_SIZE /
 						LPASS_PLATFORM_PERIODS,
 	.period_bytes_min	=	LPASS_PLATFORM_BUFFER_SIZE /
 						LPASS_PLATFORM_PERIODS,
 	.periods_min		=	LPASS_PLATFORM_PERIODS,
 	.periods_max		=	LPASS_PLATFORM_PERIODS,
 	.fifo_size		=	0,
 };

 static int lpass_platform_pcmops_open(struct snd_pcm_substream *substream)
 {
 	struct snd_pcm_runtime *runtime = substream->runtime;
 	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
 	int ret;

 	snd_soc_set_runtime_hwparams(substream, &lpass_platform_pcm_hardware);

 	runtime->dma_bytes = lpass_platform_pcm_hardware.buffer_bytes_max;

 	ret = snd_pcm_hw_constraint_integer(runtime,
 			SNDRV_PCM_HW_PARAM_PERIODS);
 	if (ret < 0) {
 		dev_err(soc_runtime->dev, "%s() setting constraints failed: %d\n",
 				__func__, ret);
 		return -EINVAL;
 	}

 	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);

 	return 0;
 }

 static int lpass_platform_pcmops_hw_params(struct snd_pcm_substream *substream,
 		struct snd_pcm_hw_params *params)
 {
 	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
 	struct lpass_data *drvdata =
 		snd_soc_platform_get_drvdata(soc_runtime->platform);
 	snd_pcm_format_t format = params_format(params);
 	unsigned int channels = params_channels(params);
 	unsigned int regval;
 	int bitwidth;
 	int ret;

 	bitwidth = snd_pcm_format_width(format);
 	if (bitwidth < 0) {
 		dev_err(soc_runtime->dev, "%s() invalid bit width given: %d\n",
 				__func__, bitwidth);
 		return bitwidth;
 	}

 	regval = LPAIF_RDMACTL_BURSTEN_INCR4 |
 			LPAIF_RDMACTL_AUDINTF_MI2S |
 			LPAIF_RDMACTL_FIFOWM_8;

 	switch (bitwidth) {
 	case 16:
 		switch (channels) {
 		case 1:
 		case 2:
 			regval |= LPAIF_RDMACTL_WPSCNT_ONE;
 			break;
 		case 4:
 			regval |= LPAIF_RDMACTL_WPSCNT_TWO;
 			break;
 		case 6:
 			regval |= LPAIF_RDMACTL_WPSCNT_THREE;
 			break;
 		case 8:
 			regval |= LPAIF_RDMACTL_WPSCNT_FOUR;
 			break;
 		default:
 			dev_err(soc_runtime->dev, "%s() invalid PCM config given: bw=%d, ch=%u\n",
 					__func__, bitwidth, channels);
 			return -EINVAL;
 		}
 		break;
 	case 24:
 	case 32:
 		switch (channels) {
 		case 1:
 			regval |= LPAIF_RDMACTL_WPSCNT_ONE;
 			break;
 		case 2:
 			regval |= LPAIF_RDMACTL_WPSCNT_TWO;
 			break;
 		case 4:
 			regval |= LPAIF_RDMACTL_WPSCNT_FOUR;
 			break;
 		case 6:
 			regval |= LPAIF_RDMACTL_WPSCNT_SIX;
 			break;
 		case 8:
 			regval |= LPAIF_RDMACTL_WPSCNT_EIGHT;
 			break;
 		default:
 			dev_err(soc_runtime->dev, "%s() invalid PCM config given: bw=%d, ch=%u\n",
 					__func__, bitwidth, channels);
 			return -EINVAL;
 		}
 		break;
 	default:
 		dev_err(soc_runtime->dev, "%s() invalid PCM config given: bw=%d, ch=%u\n",
 				__func__, bitwidth, channels);
 		return -EINVAL;
 	}

 	ret = regmap_write(drvdata->lpaif_map,
 			LPAIF_RDMACTL_REG(LPAIF_RDMA_CHAN_MI2S), regval);
 	if (ret) {
 		dev_err(soc_runtime->dev, "%s() error writing to rdmactl reg: %d\n",
 				__func__, ret);
 		return ret;
 	}

 	return 0;
 }

 static int lpass_platform_pcmops_hw_free(struct snd_pcm_substream *substream)
 {
 	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
 	struct lpass_data *drvdata =
 		snd_soc_platform_get_drvdata(soc_runtime->platform);
 	int ret;

 	ret = regmap_write(drvdata->lpaif_map,
 			LPAIF_RDMACTL_REG(LPAIF_RDMA_CHAN_MI2S), 0);
 	if (ret)
 		dev_err(soc_runtime->dev, "%s() error writing to rdmactl reg: %d\n",
 				__func__, ret);

 	return ret;
 }

 static int lpass_platform_pcmops_prepare(struct snd_pcm_substream *substream)
 {
 	struct snd_pcm_runtime *runtime = substream->runtime;
 	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
 	struct lpass_data *drvdata =
 		snd_soc_platform_get_drvdata(soc_runtime->platform);
 	int ret;

 	ret = regmap_write(drvdata->lpaif_map,
 			LPAIF_RDMABASE_REG(LPAIF_RDMA_CHAN_MI2S),
 			runtime->dma_addr);
 	if (ret) {
 		dev_err(soc_runtime->dev, "%s() error writing to rdmabase reg: %d\n",
 				__func__, ret);
 		return ret;
 	}

 	ret = regmap_write(drvdata->lpaif_map,
 			LPAIF_RDMABUFF_REG(LPAIF_RDMA_CHAN_MI2S),
 			(snd_pcm_lib_buffer_bytes(substream) >> 2) - 1);
 	if (ret) {
 		dev_err(soc_runtime->dev, "%s() error writing to rdmabuff reg: %d\n",
 				__func__, ret);
 		return ret;
 	}

 	ret = regmap_write(drvdata->lpaif_map,
 			LPAIF_RDMAPER_REG(LPAIF_RDMA_CHAN_MI2S),
 			(snd_pcm_lib_period_bytes(substream) >> 2) - 1);
 	if (ret) {
 		dev_err(soc_runtime->dev, "%s() error writing to rdmaper reg: %d\n",
 				__func__, ret);
 		return ret;
 	}

 	ret = regmap_update_bits(drvdata->lpaif_map,
 			LPAIF_RDMACTL_REG(LPAIF_RDMA_CHAN_MI2S),
 			LPAIF_RDMACTL_ENABLE_MASK, LPAIF_RDMACTL_ENABLE_ON);
 	if (ret) {
 		dev_err(soc_runtime->dev, "%s() error writing to rdmactl reg: %d\n",
 				__func__, ret);
 		return ret;
 	}

 	return 0;
 }

 static int lpass_platform_pcmops_trigger(struct snd_pcm_substream *substream,
 		int cmd)
 {
 	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
 	struct lpass_data *drvdata =
 		snd_soc_platform_get_drvdata(soc_runtime->platform);
 	int ret;

 	switch (cmd) {
 	case SNDRV_PCM_TRIGGER_START:
 	case SNDRV_PCM_TRIGGER_RESUME:
 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 		/* clear status before enabling interrupts */
 		ret = regmap_write(drvdata->lpaif_map,
 				LPAIF_IRQCLEAR_REG(LPAIF_IRQ_PORT_HOST),
 				LPAIF_IRQ_ALL(LPAIF_RDMA_CHAN_MI2S));
 		if (ret) {
 			dev_err(soc_runtime->dev, "%s() error writing to irqclear reg: %d\n",
 					__func__, ret);
 			return ret;
 		}

 		ret = regmap_update_bits(drvdata->lpaif_map,
 				LPAIF_IRQEN_REG(LPAIF_IRQ_PORT_HOST),
 				LPAIF_IRQ_ALL(LPAIF_RDMA_CHAN_MI2S),
 				LPAIF_IRQ_ALL(LPAIF_RDMA_CHAN_MI2S));
 		if (ret) {
 			dev_err(soc_runtime->dev, "%s() error writing to irqen reg: %d\n",
 					__func__, ret);
 			return ret;
 		}

 		ret = regmap_update_bits(drvdata->lpaif_map,
 				LPAIF_RDMACTL_REG(LPAIF_RDMA_CHAN_MI2S),
 				LPAIF_RDMACTL_ENABLE_MASK,
 				LPAIF_RDMACTL_ENABLE_ON);
 		if (ret) {
 			dev_err(soc_runtime->dev, "%s() error writing to rdmactl reg: %d\n",
 					__func__, ret);
 			return ret;
 		}
 		break;
 	case SNDRV_PCM_TRIGGER_STOP:
 	case SNDRV_PCM_TRIGGER_SUSPEND:
 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 		ret = regmap_update_bits(drvdata->lpaif_map,
 				LPAIF_RDMACTL_REG(LPAIF_RDMA_CHAN_MI2S),
 				LPAIF_RDMACTL_ENABLE_MASK,
 				LPAIF_RDMACTL_ENABLE_OFF);
 		if (ret) {
 			dev_err(soc_runtime->dev, "%s() error writing to rdmactl reg: %d\n",
 					__func__, ret);
 			return ret;
 		}

 		ret = regmap_update_bits(drvdata->lpaif_map,
 				LPAIF_IRQEN_REG(LPAIF_IRQ_PORT_HOST),
 				LPAIF_IRQ_ALL(LPAIF_RDMA_CHAN_MI2S), 0);
 		if (ret) {
 			dev_err(soc_runtime->dev, "%s() error writing to irqen reg: %d\n",
 					__func__, ret);
 			return ret;
 		}
 		break;
 	}

 	return 0;
 }

 static snd_pcm_uframes_t lpass_platform_pcmops_pointer(
 		struct snd_pcm_substream *substream)
 {
 	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
 	struct lpass_data *drvdata =
 			snd_soc_platform_get_drvdata(soc_runtime->platform);
 	unsigned int base_addr, curr_addr;
 	int ret;

 	ret = regmap_read(drvdata->lpaif_map,
 			LPAIF_RDMABASE_REG(LPAIF_RDMA_CHAN_MI2S), &base_addr);
 	if (ret) {
 		dev_err(soc_runtime->dev, "%s() error reading from rdmabase reg: %d\n",
 				__func__, ret);
 		return ret;
 	}

 	ret = regmap_read(drvdata->lpaif_map,
 			LPAIF_RDMACURR_REG(LPAIF_RDMA_CHAN_MI2S), &curr_addr);
 	if (ret) {
 		dev_err(soc_runtime->dev, "%s() error reading from rdmacurr reg: %d\n",
 				__func__, ret);
 		return ret;
 	}

 	return bytes_to_frames(substream->runtime, curr_addr - base_addr);
 }

 static int lpass_platform_pcmops_mmap(struct snd_pcm_substream *substream,
 		struct vm_area_struct *vma)
 {
 	struct snd_pcm_runtime *runtime = substream->runtime;

 	return dma_mmap_coherent(substream->pcm->card->dev, vma,
 			runtime->dma_area, runtime->dma_addr,
 			runtime->dma_bytes);
 }

 static struct snd_pcm_ops lpass_platform_pcm_ops = {
 	.open		= lpass_platform_pcmops_open,
 	.ioctl		= snd_pcm_lib_ioctl,
 	.hw_params	= lpass_platform_pcmops_hw_params,
 	.hw_free	= lpass_platform_pcmops_hw_free,
 	.prepare	= lpass_platform_pcmops_prepare,
 	.trigger	= lpass_platform_pcmops_trigger,
 	.pointer	= lpass_platform_pcmops_pointer,
 	.mmap		= lpass_platform_pcmops_mmap,
 };

 static irqreturn_t lpass_platform_lpaif_irq(int irq, void *data)
 {
 	struct snd_pcm_substream *substream = data;
 	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
 	struct lpass_data *drvdata =
 		snd_soc_platform_get_drvdata(soc_runtime->platform);
 	unsigned int interrupts;
 	irqreturn_t ret = IRQ_NONE;
 	int rv;

 	rv = regmap_read(drvdata->lpaif_map,
 			LPAIF_IRQSTAT_REG(LPAIF_IRQ_PORT_HOST), &interrupts);
 	if (rv) {
 		dev_err(soc_runtime->dev, "%s() error reading from irqstat reg: %d\n",
 				__func__, rv);
 		return IRQ_NONE;
 	}
 	interrupts &= LPAIF_IRQ_ALL(LPAIF_RDMA_CHAN_MI2S);

 	if (interrupts & LPAIF_IRQ_PER(LPAIF_RDMA_CHAN_MI2S)) {
 		rv = regmap_write(drvdata->lpaif_map,
 				LPAIF_IRQCLEAR_REG(LPAIF_IRQ_PORT_HOST),
 				LPAIF_IRQ_PER(LPAIF_RDMA_CHAN_MI2S));
 		if (rv) {
 			dev_err(soc_runtime->dev, "%s() error writing to irqclear reg: %d\n",
 					__func__, rv);
 			return IRQ_NONE;
 		}
 		snd_pcm_period_elapsed(substream);
 		ret = IRQ_HANDLED;
 	}

 	if (interrupts & LPAIF_IRQ_XRUN(LPAIF_RDMA_CHAN_MI2S)) {
 		rv = regmap_write(drvdata->lpaif_map,
 				LPAIF_IRQCLEAR_REG(LPAIF_IRQ_PORT_HOST),
 				LPAIF_IRQ_XRUN(LPAIF_RDMA_CHAN_MI2S));
 		if (rv) {
 			dev_err(soc_runtime->dev, "%s() error writing to irqclear reg: %d\n",
 					__func__, rv);
 			return IRQ_NONE;
 		}
 		dev_warn(soc_runtime->dev, "%s() xrun warning\n", __func__);
 		snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 		ret = IRQ_HANDLED;
 	}

 	if (interrupts & LPAIF_IRQ_ERR(LPAIF_RDMA_CHAN_MI2S)) {
 		rv = regmap_write(drvdata->lpaif_map,
 				LPAIF_IRQCLEAR_REG(LPAIF_IRQ_PORT_HOST),
 				LPAIF_IRQ_ERR(LPAIF_RDMA_CHAN_MI2S));
 		if (rv) {
 			dev_err(soc_runtime->dev, "%s() error writing to irqclear reg: %d\n",
 					__func__, rv);
 			return IRQ_NONE;
 		}
 		dev_err(soc_runtime->dev, "%s() bus access error\n", __func__);
 		snd_pcm_stop(substream, SNDRV_PCM_STATE_DISCONNECTED);
 		ret = IRQ_HANDLED;
 	}

 	return ret;
 }

 static int lpass_platform_alloc_buffer(struct snd_pcm_substream *substream,
 		struct snd_soc_pcm_runtime *soc_runtime)
 {
 	struct snd_dma_buffer *buf = &substream->dma_buffer;
 	size_t size = lpass_platform_pcm_hardware.buffer_bytes_max;

 	buf->dev.type = SNDRV_DMA_TYPE_DEV;
 	buf->dev.dev = soc_runtime->dev;
 	buf->private_data = NULL;
 	buf->area = dma_alloc_coherent(soc_runtime->dev, size, &buf->addr,
 			GFP_KERNEL);
 	if (!buf->area) {
 		dev_err(soc_runtime->dev, "%s: Could not allocate DMA buffer\n",
 				__func__);
 		return -ENOMEM;
 	}
 	buf->bytes = size;

 	return 0;
 }

 static void lpass_platform_free_buffer(struct snd_pcm_substream *substream,
 		struct snd_soc_pcm_runtime *soc_runtime)
 {
 	struct snd_dma_buffer *buf = &substream->dma_buffer;

 	if (buf->area) {
 		dma_free_coherent(soc_runtime->dev, buf->bytes, buf->area,
 				buf->addr);
 	}
 	buf->area = NULL;
 }

 static int lpass_platform_pcm_new(struct snd_soc_pcm_runtime *soc_runtime)
 {
 	struct snd_pcm *pcm = soc_runtime->pcm;
 	struct snd_pcm_substream *substream =
 		pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
 	struct lpass_data *drvdata =
 		snd_soc_platform_get_drvdata(soc_runtime->platform);
 	int ret;

 	soc_runtime->dev->coherent_dma_mask = DMA_BIT_MASK(32);
 	soc_runtime->dev->dma_mask = &soc_runtime->dev->coherent_dma_mask;

 	ret = lpass_platform_alloc_buffer(substream, soc_runtime);
 	if (ret)
 		return ret;

 	ret = devm_request_irq(soc_runtime->dev, drvdata->lpaif_irq,
 			lpass_platform_lpaif_irq, IRQF_TRIGGER_RISING,
 			"lpass-irq-lpaif", substream);
 	if (ret) {
 		dev_err(soc_runtime->dev, "%s() irq request failed: %d\n",
 				__func__, ret);
 		goto err_buf;
 	}

 	/* ensure audio hardware is disabled */
 	ret = regmap_write(drvdata->lpaif_map,
 			LPAIF_IRQEN_REG(LPAIF_IRQ_PORT_HOST), 0);
 	if (ret) {
 		dev_err(soc_runtime->dev, "%s() error writing to irqen reg: %d\n",
 				__func__, ret);
 		return ret;
 	}
 	ret = regmap_write(drvdata->lpaif_map,
 			LPAIF_RDMACTL_REG(LPAIF_RDMA_CHAN_MI2S), 0);
 	if (ret) {
 		dev_err(soc_runtime->dev, "%s() error writing to rdmactl reg: %d\n",
 				__func__, ret);
 		return ret;
 	}

 	return 0;

 err_buf:
 	lpass_platform_free_buffer(substream, soc_runtime);
 	return ret;
 }

 static void lpass_platform_pcm_free(struct snd_pcm *pcm)
 {
 	struct snd_pcm_substream *substream =
 		pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
 	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;

 	lpass_platform_free_buffer(substream, soc_runtime);
 }

 static struct snd_soc_platform_driver lpass_platform_driver = {
 	.pcm_new	= lpass_platform_pcm_new,
 	.pcm_free	= lpass_platform_pcm_free,
 	.ops		= &lpass_platform_pcm_ops,
 };

 int asoc_qcom_lpass_platform_register(struct platform_device *pdev)
 {
 	struct lpass_data *drvdata = platform_get_drvdata(pdev);

 	drvdata->lpaif_irq = platform_get_irq_byname(pdev, "lpass-irq-lpaif");
 	if (drvdata->lpaif_irq < 0) {
 		dev_err(&pdev->dev, "%s() error getting irq handle: %d\n",
 				__func__, drvdata->lpaif_irq);
 		return -ENODEV;
 	}

 	return devm_snd_soc_register_platform(&pdev->dev,
 			&lpass_platform_driver);
 }
 EXPORT_SYMBOL_GPL(asoc_qcom_lpass_platform_register);

 MODULE_DESCRIPTION("QTi LPASS Platform Driver");
 MODULE_LICENSE("GPL v2");
	/*
	* Copyright (c) 2010-2011,2013-2015 The Linux Foundation. All rights reserved.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 and
	* only 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.
	*
	* lpass-platform.c -- ALSA SoC platform driver for QTi LPASS
	*/

	#include <linux/compiler.h>
	#include <linux/device.h>
	#include <linux/dma-mapping.h>
	#include <linux/err.h>
	#include <linux/export.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/io.h>
	#include <linux/platform_device.h>
	#include <sound/memalloc.h>
	#include <sound/pcm.h>
	#include <sound/pcm_params.h>
	#include <linux/regmap.h>
	#include <sound/soc.h>
	#include "lpass-lpaif-ipq806x.h"
	#include "lpass.h"

	#define LPASS_PLATFORM_BUFFER_SIZE (16 * 1024)
	#define LPASS_PLATFORM_PERIODS 2

	static struct snd_pcm_hardware lpass_platform_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 \|
	SNDRV_PCM_FMTBIT_S24 \|
	SNDRV_PCM_FMTBIT_S32,
	.rates = SNDRV_PCM_RATE_8000_192000,
	.rate_min = 8000,
	.rate_max = 192000,
	.channels_min = 1,
	.channels_max = 8,
	.buffer_bytes_max = LPASS_PLATFORM_BUFFER_SIZE,
	.period_bytes_max = LPASS_PLATFORM_BUFFER_SIZE /
	LPASS_PLATFORM_PERIODS,
	.period_bytes_min = LPASS_PLATFORM_BUFFER_SIZE /
	LPASS_PLATFORM_PERIODS,
	.periods_min = LPASS_PLATFORM_PERIODS,
	.periods_max = LPASS_PLATFORM_PERIODS,
	.fifo_size = 0,
	};

	static int lpass_platform_pcmops_open(struct snd_pcm_substream *substream)
	{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
	int ret;

	snd_soc_set_runtime_hwparams(substream, &lpass_platform_pcm_hardware);

	runtime->dma_bytes = lpass_platform_pcm_hardware.buffer_bytes_max;

	ret = snd_pcm_hw_constraint_integer(runtime,
	SNDRV_PCM_HW_PARAM_PERIODS);
	if (ret < 0) {
	dev_err(soc_runtime->dev, "%s() setting constraints failed: %d\n",
	__func__, ret);
	return -EINVAL;
	}

	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);

	return 0;
	}

	static int lpass_platform_pcmops_hw_params(struct snd_pcm_substream *substream,
	struct snd_pcm_hw_params *params)
	{
	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
	struct lpass_data *drvdata =
	snd_soc_platform_get_drvdata(soc_runtime->platform);
	snd_pcm_format_t format = params_format(params);
	unsigned int channels = params_channels(params);
	unsigned int regval;
	int bitwidth;
	int ret;

	bitwidth = snd_pcm_format_width(format);
	if (bitwidth < 0) {
	dev_err(soc_runtime->dev, "%s() invalid bit width given: %d\n",
	__func__, bitwidth);
	return bitwidth;
	}

	regval = LPAIF_RDMACTL_BURSTEN_INCR4 \|
	LPAIF_RDMACTL_AUDINTF_MI2S \|
	LPAIF_RDMACTL_FIFOWM_8;

	switch (bitwidth) {
	case 16:
	switch (channels) {
	case 1:
	case 2:
	regval \|= LPAIF_RDMACTL_WPSCNT_ONE;
	break;
	case 4:
	regval \|= LPAIF_RDMACTL_WPSCNT_TWO;
	break;
	case 6:
	regval \|= LPAIF_RDMACTL_WPSCNT_THREE;
	break;
	case 8:
	regval \|= LPAIF_RDMACTL_WPSCNT_FOUR;
	break;
	default:
	dev_err(soc_runtime->dev, "%s() invalid PCM config given: bw=%d, ch=%u\n",
	__func__, bitwidth, channels);
	return -EINVAL;
	}
	break;
	case 24:
	case 32:
	switch (channels) {
	case 1:
	regval \|= LPAIF_RDMACTL_WPSCNT_ONE;
	break;
	case 2:
	regval \|= LPAIF_RDMACTL_WPSCNT_TWO;
	break;
	case 4:
	regval \|= LPAIF_RDMACTL_WPSCNT_FOUR;
	break;
	case 6:
	regval \|= LPAIF_RDMACTL_WPSCNT_SIX;
	break;
	case 8:
	regval \|= LPAIF_RDMACTL_WPSCNT_EIGHT;
	break;
	default:
	dev_err(soc_runtime->dev, "%s() invalid PCM config given: bw=%d, ch=%u\n",
	__func__, bitwidth, channels);
	return -EINVAL;
	}
	break;
	default:
	dev_err(soc_runtime->dev, "%s() invalid PCM config given: bw=%d, ch=%u\n",
	__func__, bitwidth, channels);
	return -EINVAL;
	}

	ret = regmap_write(drvdata->lpaif_map,
	LPAIF_RDMACTL_REG(LPAIF_RDMA_CHAN_MI2S), regval);
	if (ret) {
	dev_err(soc_runtime->dev, "%s() error writing to rdmactl reg: %d\n",
	__func__, ret);
	return ret;
	}

	return 0;
	}

	static int lpass_platform_pcmops_hw_free(struct snd_pcm_substream *substream)
	{
	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
	struct lpass_data *drvdata =
	snd_soc_platform_get_drvdata(soc_runtime->platform);
	int ret;

	ret = regmap_write(drvdata->lpaif_map,
	LPAIF_RDMACTL_REG(LPAIF_RDMA_CHAN_MI2S), 0);
	if (ret)
	dev_err(soc_runtime->dev, "%s() error writing to rdmactl reg: %d\n",
	__func__, ret);

	return ret;
	}

	static int lpass_platform_pcmops_prepare(struct snd_pcm_substream *substream)
	{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
	struct lpass_data *drvdata =
	snd_soc_platform_get_drvdata(soc_runtime->platform);
	int ret;

	ret = regmap_write(drvdata->lpaif_map,
	LPAIF_RDMABASE_REG(LPAIF_RDMA_CHAN_MI2S),
	runtime->dma_addr);
	if (ret) {
	dev_err(soc_runtime->dev, "%s() error writing to rdmabase reg: %d\n",
	__func__, ret);
	return ret;
	}

	ret = regmap_write(drvdata->lpaif_map,
	LPAIF_RDMABUFF_REG(LPAIF_RDMA_CHAN_MI2S),
	(snd_pcm_lib_buffer_bytes(substream) >> 2) - 1);
	if (ret) {
	dev_err(soc_runtime->dev, "%s() error writing to rdmabuff reg: %d\n",
	__func__, ret);
	return ret;
	}

	ret = regmap_write(drvdata->lpaif_map,
	LPAIF_RDMAPER_REG(LPAIF_RDMA_CHAN_MI2S),
	(snd_pcm_lib_period_bytes(substream) >> 2) - 1);
	if (ret) {
	dev_err(soc_runtime->dev, "%s() error writing to rdmaper reg: %d\n",
	__func__, ret);
	return ret;
	}

	ret = regmap_update_bits(drvdata->lpaif_map,
	LPAIF_RDMACTL_REG(LPAIF_RDMA_CHAN_MI2S),
	LPAIF_RDMACTL_ENABLE_MASK, LPAIF_RDMACTL_ENABLE_ON);
	if (ret) {
	dev_err(soc_runtime->dev, "%s() error writing to rdmactl reg: %d\n",
	__func__, ret);
	return ret;
	}

	return 0;
	}

	static int lpass_platform_pcmops_trigger(struct snd_pcm_substream *substream,
	int cmd)
	{
	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
	struct lpass_data *drvdata =
	snd_soc_platform_get_drvdata(soc_runtime->platform);
	int ret;

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
	/* clear status before enabling interrupts */
	ret = regmap_write(drvdata->lpaif_map,
	LPAIF_IRQCLEAR_REG(LPAIF_IRQ_PORT_HOST),
	LPAIF_IRQ_ALL(LPAIF_RDMA_CHAN_MI2S));
	if (ret) {
	dev_err(soc_runtime->dev, "%s() error writing to irqclear reg: %d\n",
	__func__, ret);
	return ret;
	}

	ret = regmap_update_bits(drvdata->lpaif_map,
	LPAIF_IRQEN_REG(LPAIF_IRQ_PORT_HOST),
	LPAIF_IRQ_ALL(LPAIF_RDMA_CHAN_MI2S),
	LPAIF_IRQ_ALL(LPAIF_RDMA_CHAN_MI2S));
	if (ret) {
	dev_err(soc_runtime->dev, "%s() error writing to irqen reg: %d\n",
	__func__, ret);
	return ret;
	}

	ret = regmap_update_bits(drvdata->lpaif_map,
	LPAIF_RDMACTL_REG(LPAIF_RDMA_CHAN_MI2S),
	LPAIF_RDMACTL_ENABLE_MASK,
	LPAIF_RDMACTL_ENABLE_ON);
	if (ret) {
	dev_err(soc_runtime->dev, "%s() error writing to rdmactl reg: %d\n",
	__func__, ret);
	return ret;
	}
	break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
	ret = regmap_update_bits(drvdata->lpaif_map,
	LPAIF_RDMACTL_REG(LPAIF_RDMA_CHAN_MI2S),
	LPAIF_RDMACTL_ENABLE_MASK,
	LPAIF_RDMACTL_ENABLE_OFF);
	if (ret) {
	dev_err(soc_runtime->dev, "%s() error writing to rdmactl reg: %d\n",
	__func__, ret);
	return ret;
	}

	ret = regmap_update_bits(drvdata->lpaif_map,
	LPAIF_IRQEN_REG(LPAIF_IRQ_PORT_HOST),
	LPAIF_IRQ_ALL(LPAIF_RDMA_CHAN_MI2S), 0);
	if (ret) {
	dev_err(soc_runtime->dev, "%s() error writing to irqen reg: %d\n",
	__func__, ret);
	return ret;
	}
	break;
	}

	return 0;
	}

	static snd_pcm_uframes_t lpass_platform_pcmops_pointer(
	struct snd_pcm_substream *substream)
	{
	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
	struct lpass_data *drvdata =
	snd_soc_platform_get_drvdata(soc_runtime->platform);
	unsigned int base_addr, curr_addr;
	int ret;

	ret = regmap_read(drvdata->lpaif_map,
	LPAIF_RDMABASE_REG(LPAIF_RDMA_CHAN_MI2S), &base_addr);
	if (ret) {
	dev_err(soc_runtime->dev, "%s() error reading from rdmabase reg: %d\n",
	__func__, ret);
	return ret;
	}

	ret = regmap_read(drvdata->lpaif_map,
	LPAIF_RDMACURR_REG(LPAIF_RDMA_CHAN_MI2S), &curr_addr);
	if (ret) {
	dev_err(soc_runtime->dev, "%s() error reading from rdmacurr reg: %d\n",
	__func__, ret);
	return ret;
	}

	return bytes_to_frames(substream->runtime, curr_addr - base_addr);
	}

	static int lpass_platform_pcmops_mmap(struct snd_pcm_substream *substream,
	struct vm_area_struct *vma)
	{
	struct snd_pcm_runtime *runtime = substream->runtime;

	return dma_mmap_coherent(substream->pcm->card->dev, vma,
	runtime->dma_area, runtime->dma_addr,
	runtime->dma_bytes);
	}

	static struct snd_pcm_ops lpass_platform_pcm_ops = {
	.open = lpass_platform_pcmops_open,
	.ioctl = snd_pcm_lib_ioctl,
	.hw_params = lpass_platform_pcmops_hw_params,
	.hw_free = lpass_platform_pcmops_hw_free,
	.prepare = lpass_platform_pcmops_prepare,
	.trigger = lpass_platform_pcmops_trigger,
	.pointer = lpass_platform_pcmops_pointer,
	.mmap = lpass_platform_pcmops_mmap,
	};

	static irqreturn_t lpass_platform_lpaif_irq(int irq, void *data)
	{
	struct snd_pcm_substream *substream = data;
	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
	struct lpass_data *drvdata =
	snd_soc_platform_get_drvdata(soc_runtime->platform);
	unsigned int interrupts;
	irqreturn_t ret = IRQ_NONE;
	int rv;

	rv = regmap_read(drvdata->lpaif_map,
	LPAIF_IRQSTAT_REG(LPAIF_IRQ_PORT_HOST), &interrupts);
	if (rv) {
	dev_err(soc_runtime->dev, "%s() error reading from irqstat reg: %d\n",
	__func__, rv);
	return IRQ_NONE;
	}
	interrupts &= LPAIF_IRQ_ALL(LPAIF_RDMA_CHAN_MI2S);

	if (interrupts & LPAIF_IRQ_PER(LPAIF_RDMA_CHAN_MI2S)) {
	rv = regmap_write(drvdata->lpaif_map,
	LPAIF_IRQCLEAR_REG(LPAIF_IRQ_PORT_HOST),
	LPAIF_IRQ_PER(LPAIF_RDMA_CHAN_MI2S));
	if (rv) {
	dev_err(soc_runtime->dev, "%s() error writing to irqclear reg: %d\n",
	__func__, rv);
	return IRQ_NONE;
	}
	snd_pcm_period_elapsed(substream);
	ret = IRQ_HANDLED;
	}

	if (interrupts & LPAIF_IRQ_XRUN(LPAIF_RDMA_CHAN_MI2S)) {
	rv = regmap_write(drvdata->lpaif_map,
	LPAIF_IRQCLEAR_REG(LPAIF_IRQ_PORT_HOST),
	LPAIF_IRQ_XRUN(LPAIF_RDMA_CHAN_MI2S));
	if (rv) {
	dev_err(soc_runtime->dev, "%s() error writing to irqclear reg: %d\n",
	__func__, rv);
	return IRQ_NONE;
	}
	dev_warn(soc_runtime->dev, "%s() xrun warning\n", __func__);
	snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
	ret = IRQ_HANDLED;
	}

	if (interrupts & LPAIF_IRQ_ERR(LPAIF_RDMA_CHAN_MI2S)) {
	rv = regmap_write(drvdata->lpaif_map,
	LPAIF_IRQCLEAR_REG(LPAIF_IRQ_PORT_HOST),
	LPAIF_IRQ_ERR(LPAIF_RDMA_CHAN_MI2S));
	if (rv) {
	dev_err(soc_runtime->dev, "%s() error writing to irqclear reg: %d\n",
	__func__, rv);
	return IRQ_NONE;
	}
	dev_err(soc_runtime->dev, "%s() bus access error\n", __func__);
	snd_pcm_stop(substream, SNDRV_PCM_STATE_DISCONNECTED);
	ret = IRQ_HANDLED;
	}

	return ret;
	}

	static int lpass_platform_alloc_buffer(struct snd_pcm_substream *substream,
	struct snd_soc_pcm_runtime *soc_runtime)
	{
	struct snd_dma_buffer *buf = &substream->dma_buffer;
	size_t size = lpass_platform_pcm_hardware.buffer_bytes_max;

	buf->dev.type = SNDRV_DMA_TYPE_DEV;
	buf->dev.dev = soc_runtime->dev;
	buf->private_data = NULL;
	buf->area = dma_alloc_coherent(soc_runtime->dev, size, &buf->addr,
	GFP_KERNEL);
	if (!buf->area) {
	dev_err(soc_runtime->dev, "%s: Could not allocate DMA buffer\n",
	__func__);
	return -ENOMEM;
	}
	buf->bytes = size;

	return 0;
	}

	static void lpass_platform_free_buffer(struct snd_pcm_substream *substream,
	struct snd_soc_pcm_runtime *soc_runtime)
	{
	struct snd_dma_buffer *buf = &substream->dma_buffer;

	if (buf->area) {
	dma_free_coherent(soc_runtime->dev, buf->bytes, buf->area,
	buf->addr);
	}
	buf->area = NULL;
	}

	static int lpass_platform_pcm_new(struct snd_soc_pcm_runtime *soc_runtime)
	{
	struct snd_pcm *pcm = soc_runtime->pcm;
	struct snd_pcm_substream *substream =
	pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
	struct lpass_data *drvdata =
	snd_soc_platform_get_drvdata(soc_runtime->platform);
	int ret;

	soc_runtime->dev->coherent_dma_mask = DMA_BIT_MASK(32);
	soc_runtime->dev->dma_mask = &soc_runtime->dev->coherent_dma_mask;

	ret = lpass_platform_alloc_buffer(substream, soc_runtime);
	if (ret)
	return ret;

	ret = devm_request_irq(soc_runtime->dev, drvdata->lpaif_irq,
	lpass_platform_lpaif_irq, IRQF_TRIGGER_RISING,
	"lpass-irq-lpaif", substream);
	if (ret) {
	dev_err(soc_runtime->dev, "%s() irq request failed: %d\n",
	__func__, ret);
	goto err_buf;
	}

	/* ensure audio hardware is disabled */
	ret = regmap_write(drvdata->lpaif_map,
	LPAIF_IRQEN_REG(LPAIF_IRQ_PORT_HOST), 0);
	if (ret) {
	dev_err(soc_runtime->dev, "%s() error writing to irqen reg: %d\n",
	__func__, ret);
	return ret;
	}
	ret = regmap_write(drvdata->lpaif_map,
	LPAIF_RDMACTL_REG(LPAIF_RDMA_CHAN_MI2S), 0);
	if (ret) {
	dev_err(soc_runtime->dev, "%s() error writing to rdmactl reg: %d\n",
	__func__, ret);
	return ret;
	}

	return 0;

	err_buf:
	lpass_platform_free_buffer(substream, soc_runtime);
	return ret;
	}

	static void lpass_platform_pcm_free(struct snd_pcm *pcm)
	{
	struct snd_pcm_substream *substream =
	pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;

	lpass_platform_free_buffer(substream, soc_runtime);
	}

	static struct snd_soc_platform_driver lpass_platform_driver = {
	.pcm_new = lpass_platform_pcm_new,
	.pcm_free = lpass_platform_pcm_free,
	.ops = &lpass_platform_pcm_ops,
	};

	int asoc_qcom_lpass_platform_register(struct platform_device *pdev)
	{
	struct lpass_data *drvdata = platform_get_drvdata(pdev);

	drvdata->lpaif_irq = platform_get_irq_byname(pdev, "lpass-irq-lpaif");
	if (drvdata->lpaif_irq < 0) {
	dev_err(&pdev->dev, "%s() error getting irq handle: %d\n",
	__func__, drvdata->lpaif_irq);
	return -ENODEV;
	}

	return devm_snd_soc_register_platform(&pdev->dev,
	&lpass_platform_driver);
	}
	EXPORT_SYMBOL_GPL(asoc_qcom_lpass_platform_register);

	MODULE_DESCRIPTION("QTi LPASS Platform Driver");
	MODULE_LICENSE("GPL v2");