/*
 * Copyright (C) ST-Ericsson SA 2010
 *
 * Author: Ola Lilja <ola.o.lilja@stericsson.com>,
 *         Roger Nilsson <roger.xr.nilsson@stericsson.com>
 *         for ST-Ericsson.
 *
 * License terms:
 *
 * 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.
 */

#include <asm/page.h>

#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/workqueue.h>

#include <plat/ste_dma40.h>

#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>

#include "ux500_pcm.h"

static struct snd_pcm_hardware ux500_pcm_hw_playback = {
	.info = SNDRV_PCM_INFO_INTERLEAVED |
		SNDRV_PCM_INFO_MMAP |
		SNDRV_PCM_INFO_RESUME |
		SNDRV_PCM_INFO_PAUSE,
	.formats = SNDRV_PCM_FMTBIT_S16_LE |
		SNDRV_PCM_FMTBIT_U16_LE |
		SNDRV_PCM_FMTBIT_S16_BE |
		SNDRV_PCM_FMTBIT_U16_BE,
	.rates = SNDRV_PCM_RATE_KNOT,
	.rate_min = UX500_PLATFORM_MIN_RATE_PLAYBACK,
	.rate_max = UX500_PLATFORM_MAX_RATE_PLAYBACK,
	.channels_min = UX500_PLATFORM_MIN_CHANNELS,
	.channels_max = UX500_PLATFORM_MAX_CHANNELS,
	.buffer_bytes_max = UX500_PLATFORM_BUFFER_BYTES_MAX,
	.period_bytes_min = UX500_PLATFORM_PERIODS_BYTES_MIN,
	.period_bytes_max = UX500_PLATFORM_PERIODS_BYTES_MAX,
	.periods_min = UX500_PLATFORM_PERIODS_MIN,
	.periods_max = UX500_PLATFORM_PERIODS_MAX,
};

static struct snd_pcm_hardware ux500_pcm_hw_capture = {
	.info = SNDRV_PCM_INFO_INTERLEAVED |
		SNDRV_PCM_INFO_MMAP |
		SNDRV_PCM_INFO_RESUME |
		SNDRV_PCM_INFO_PAUSE,
	.formats = SNDRV_PCM_FMTBIT_S16_LE |
		SNDRV_PCM_FMTBIT_U16_LE |
		SNDRV_PCM_FMTBIT_S16_BE |
		SNDRV_PCM_FMTBIT_U16_BE,
	.rates = SNDRV_PCM_RATE_KNOT,
	.rate_min = UX500_PLATFORM_MIN_RATE_CAPTURE,
	.rate_max = UX500_PLATFORM_MAX_RATE_CAPTURE,
	.channels_min = UX500_PLATFORM_MIN_CHANNELS,
	.channels_max = UX500_PLATFORM_MAX_CHANNELS,
	.buffer_bytes_max = UX500_PLATFORM_BUFFER_BYTES_MAX,
	.period_bytes_min = UX500_PLATFORM_PERIODS_BYTES_MIN,
	.period_bytes_max = UX500_PLATFORM_PERIODS_BYTES_MAX,
	.periods_min = UX500_PLATFORM_PERIODS_MIN,
	.periods_max = UX500_PLATFORM_PERIODS_MAX,
};

static const char *stream_str(struct snd_pcm_substream *substream)
{
	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
		return "Playback";
	else
		return "Capture";
}

static void
ux500_pcm_dma_eot_handler(void *data)
{
	struct snd_pcm_substream *substream = data;
	struct snd_pcm_runtime *runtime;
	struct ux500_pcm_private *private;
	struct snd_soc_pcm_runtime *rtd = substream->private_data;
	struct snd_soc_dai *dai = rtd->cpu_dai;

	pr_debug("%s: MSP %d (%s): Enter.\n", __func__,
		dai->id,
		stream_str(substream));

	if (substream) {
		runtime = substream->runtime;
		private = substream->runtime->private_data;

		/* calc the offset in the circular buffer */
		private->offset += frames_to_bytes(runtime,
				runtime->period_size);
		private->offset %= frames_to_bytes(runtime,
				runtime->period_size) * runtime->periods;

		snd_pcm_period_elapsed(substream);
	}
}

static int
ux500_pcm_dma_start(
	struct snd_pcm_substream *substream,
	dma_addr_t dma_addr,
	int period_cnt,
	size_t period_len,
	int dai_idx,
	int stream_id)
{
	dma_cookie_t status_submit;
	int direction;
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct snd_soc_pcm_runtime *rtd = substream->private_data;
	struct snd_soc_dai *dai = rtd->cpu_dai;
	struct ux500_pcm_private *private = runtime->private_data;
	struct dma_async_tx_descriptor *cdesc;
	struct ux500_pcm_dma_params *dma_params;

	pr_debug("%s: Enter\n", __func__);

	dma_params = snd_soc_dai_get_dma_data(dai, substream);

	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
		direction = DMA_TO_DEVICE;
	else
		direction = DMA_FROM_DEVICE;

	cdesc = private->pipeid->device->device_prep_dma_cyclic(
		private->pipeid,
		dma_addr,
		period_cnt * period_len,
		period_len,
		direction,
		NULL);

	if (IS_ERR(cdesc)) {
		pr_err("%s: ERROR: device_prep_dma_cyclic failed (%ld)!\n",
			__func__,
			PTR_ERR(cdesc));
		return -EINVAL;
	}

	cdesc->callback = ux500_pcm_dma_eot_handler;
	cdesc->callback_param = substream;

	status_submit = dmaengine_submit(cdesc);

	if (dma_submit_error(status_submit)) {
		pr_err("%s: ERROR: dmaengine_submit failed!\n", __func__);
		return -EINVAL;
	}

	dma_async_issue_pending(private->pipeid);

	return 0;
}

static void
ux500_pcm_dma_stop(struct work_struct *work)
{
	struct ux500_pcm_private *private = container_of(work,
		struct ux500_pcm_private, ws_stop);

	if (private->pipeid != NULL) {
		dmaengine_terminate_all(private->pipeid);
		dma_release_channel(private->pipeid);
		private->pipeid = NULL;
	}
}

static void
ux500_pcm_dma_hw_free(
	struct device *dev,
	struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct snd_dma_buffer *buf = runtime->dma_buffer_p;

	if (runtime->dma_area == NULL)
		return;

	if (buf != &substream->dma_buffer) {
		dma_free_coherent(
			buf->dev.dev,
			buf->bytes,
			buf->area,
			buf->addr);
		kfree(runtime->dma_buffer_p);
	}

	snd_pcm_set_runtime_buffer(substream, NULL);
}

static int ux500_pcm_open(struct snd_pcm_substream *substream)
{
	int stream_id = substream->pstr->stream;
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct ux500_pcm_private *private;
	struct snd_soc_pcm_runtime *rtd = substream->private_data;
	struct snd_soc_dai *dai = rtd->cpu_dai;
	int ret;

	pr_debug("%s: MSP %d (%s): Enter.\n", __func__,
		dai->id,
		stream_str(substream));

	pr_debug("%s: Set runtime hwparams.\n", __func__);
	if (stream_id == SNDRV_PCM_STREAM_PLAYBACK)
		snd_soc_set_runtime_hwparams(substream, &ux500_pcm_hw_playback);
	else
		snd_soc_set_runtime_hwparams(substream, &ux500_pcm_hw_capture);

	/* 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) {
		pr_err("%s: Error: snd_pcm_hw_constraints failed (%d)\n",
			__func__,
			ret);
		return ret;
	}

	pr_debug("%s: Init runtime private data.\n", __func__);
	private = kzalloc(sizeof(struct ux500_pcm_private), GFP_KERNEL);
	if (private == NULL)
		return -ENOMEM;
	private->msp_id = dai->id;
	private->wq = alloc_ordered_workqueue("ux500/pcm", 0);
	INIT_WORK(&private->ws_stop, ux500_pcm_dma_stop);

	runtime->private_data = private;

	pr_debug("%s: Set hw-struct for %s.\n",
		__func__,
		stream_str(substream));

	runtime->hw = (stream_id == SNDRV_PCM_STREAM_PLAYBACK) ?
		ux500_pcm_hw_playback : ux500_pcm_hw_capture;

	return 0;
}

static int ux500_pcm_close(struct snd_pcm_substream *substream)
{
	struct ux500_pcm_private *private = substream->runtime->private_data;

	pr_debug("%s: Enter\n", __func__);

	if (private->pipeid != NULL) {
		dma_release_channel(private->pipeid);
		private->pipeid = NULL;
	}

	destroy_workqueue(private->wq);
	kfree(private);

	return 0;
}

static int ux500_pcm_hw_params(struct snd_pcm_substream *substream,
			struct snd_pcm_hw_params *hw_params)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct snd_dma_buffer *buf = runtime->dma_buffer_p;
	int ret = 0;
	int size;

	pr_debug("%s: Enter\n", __func__);

	size = params_buffer_bytes(hw_params);

	if (buf) {
		if (buf->bytes >= size)
			goto out;
		ux500_pcm_dma_hw_free(NULL, substream);
	}

	if (substream->dma_buffer.area != NULL &&
		substream->dma_buffer.bytes >= size) {
		buf = &substream->dma_buffer;
	} else {
		buf = kmalloc(sizeof(struct snd_dma_buffer), GFP_KERNEL);
		if (!buf)
			goto nomem;

		buf->dev.type = SNDRV_DMA_TYPE_DEV;
		buf->dev.dev = NULL;
		buf->area = dma_alloc_coherent(
			NULL,
			size,
			&buf->addr,
			GFP_KERNEL);
		buf->bytes = size;
		buf->private_data = NULL;

		if (!buf->area)
			goto free;
	}
	snd_pcm_set_runtime_buffer(substream, buf);
	ret = 1;
 out:
	runtime->dma_bytes = size;
	return ret;

 free:
	kfree(buf);
 nomem:
	return -ENOMEM;
}

static int
ux500_pcm_hw_free(struct snd_pcm_substream *substream)
{
	pr_debug("%s: Enter\n", __func__);

	ux500_pcm_dma_hw_free(NULL, substream);

	return 0;
}

static int
ux500_pcm_prepare(struct snd_pcm_substream *substream)
{
	struct stedma40_chan_cfg *dma_cfg;
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct snd_soc_pcm_runtime *rtd = substream->private_data;
	struct snd_soc_dai *dai = rtd->cpu_dai;
	struct ux500_pcm_private *private = runtime->private_data;
	struct ux500_pcm_dma_params *dma_params;
	dma_cap_mask_t mask;
	u16 per_data_width, mem_data_width;

	pr_debug("%s: Enter\n", __func__);

	if (private->pipeid != NULL) {
		dma_release_channel(private->pipeid);
		private->pipeid = NULL;
	}

	dma_params = snd_soc_dai_get_dma_data(dai, substream);

	mem_data_width = STEDMA40_HALFWORD_WIDTH;

	switch (dma_params->data_size) {
	case 32:
		per_data_width = STEDMA40_WORD_WIDTH;
		break;
	case 16:
		per_data_width = STEDMA40_HALFWORD_WIDTH;
		break;
	case 8:
		per_data_width = STEDMA40_BYTE_WIDTH;
		break;
	default:
		per_data_width = STEDMA40_WORD_WIDTH;
		pr_warn("%s: Unknown data-size (%d)! Assuming 32 bits.\n",
			__func__, dma_params->data_size);
	}

	dma_cfg = dma_params->dma_cfg;

	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
		dma_cfg->src_info.data_width = mem_data_width;
		dma_cfg->dst_info.data_width = per_data_width;
	} else {
		dma_cfg->src_info.data_width = per_data_width;
		dma_cfg->dst_info.data_width = mem_data_width;
	}

	dma_cap_zero(mask);
	dma_cap_set(DMA_SLAVE, mask);

	private->pipeid = dma_request_channel(mask, stedma40_filter, dma_cfg);

	return 0;
}

static int
ux500_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
{
	int ret = 0;
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct ux500_pcm_private *private = runtime->private_data;
	int stream_id = substream->pstr->stream;

	pr_debug("%s: Enter\n", __func__);

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
		pr_debug("%s: START/PAUSE-RELEASE\n", __func__);
		if (runtime->status->state == SNDRV_PCM_STATE_XRUN) {
			pr_debug("XRUN occurred\n");
				return 0;
		}

		private->offset = 0;
		ret = ux500_pcm_dma_start(
				substream,
				runtime->dma_addr,
				runtime->periods,
				frames_to_bytes(runtime, runtime->period_size),
				private->msp_id,
				stream_id);
		if (ret) {
			pr_err("%s: Failed to configure I2S!\n", __func__);
			return -EINVAL;
		}
		break;
	case SNDRV_PCM_TRIGGER_RESUME:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
		pr_debug("%s: SNDRV_PCM_TRIGGER_STOP\n", __func__);
		queue_work(private->wq, &private->ws_stop);
		break;

	default:
		pr_err("%s: Invalid command in pcm trigger\n",
			__func__);
		return -EINVAL;
	}

	return ret;
}

static snd_pcm_uframes_t
ux500_pcm_pointer(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct ux500_pcm_private *private = runtime->private_data;

	pr_debug("%s: dma_offset %d frame %ld\n", __func__, private->offset,
			bytes_to_frames(substream->runtime, private->offset));

	return bytes_to_frames(substream->runtime, private->offset);
}

static int
ux500_pcm_mmap(
	struct snd_pcm_substream *substream,
	struct vm_area_struct *vma)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	pr_debug("%s: Enter.\n", __func__);

	return dma_mmap_coherent(
		NULL,
		vma,
		runtime->dma_area,
		runtime->dma_addr,
		runtime->dma_bytes);
}

static struct snd_pcm_ops ux500_pcm_ops = {
	.open		= ux500_pcm_open,
	.close		= ux500_pcm_close,
	.ioctl		= snd_pcm_lib_ioctl,
	.hw_params	= ux500_pcm_hw_params,
	.hw_free	= ux500_pcm_hw_free,
	.prepare	= ux500_pcm_prepare,
	.trigger	= ux500_pcm_trigger,
	.pointer	= ux500_pcm_pointer,
	.mmap		= ux500_pcm_mmap
};

int ux500_pcm_new(struct snd_soc_pcm_runtime *rtd)
{
	struct snd_pcm *pcm = rtd->pcm;

	pr_debug("%s: pcm = %d\n", __func__, (int)pcm);

	pcm->info_flags = 0;
	strcpy(pcm->name, "UX500_PCM");

	pr_debug("%s: pcm->name = %s.\n", __func__, pcm->name);

	return 0;
}

static void ux500_pcm_free(struct snd_pcm *pcm)
{
	pr_debug("%s: Enter\n", __func__);
}

static int ux500_pcm_suspend(struct snd_soc_dai *dai)
{
	pr_debug("%s: Enter\n", __func__);

	return 0;
}

static int ux500_pcm_resume(struct snd_soc_dai *dai)
{
	pr_debug("%s: Enter\n", __func__);

	return 0;
}

struct snd_soc_platform_driver ux500_pcm_soc_drv = {
	.ops		= &ux500_pcm_ops,
	.pcm_new        = ux500_pcm_new,
	.pcm_free       = ux500_pcm_free,
	.suspend        = ux500_pcm_suspend,
	.resume         = ux500_pcm_resume,
};
EXPORT_SYMBOL(ux500_pcm_soc_drv);

static int __devexit ux500_pcm_drv_probe(struct platform_device *pdev)
{
	int ret;

	pr_info("%s: Register ux500-pcm SoC platform driver.\n", __func__);
	ret = snd_soc_register_platform(&pdev->dev, &ux500_pcm_soc_drv);
	if (ret < 0) {
		pr_err("%s: Error: Failed to register "
			"ux500-pcm SoC platform driver (%d)!\n",
			__func__,
			ret);
		return ret;
	}

	return 0;
}

static int __devinit ux500_pcm_drv_remove(struct platform_device *pdev)
{
	pr_info("%s: Unregister ux500-pcm SoC platform driver.\n", __func__);
	snd_soc_unregister_platform(&pdev->dev);

	return 0;
}

static struct platform_driver ux500_pcm_driver = {
	.driver = {
		.name = "ux500-pcm",
		.owner = THIS_MODULE,
	},

	.probe = ux500_pcm_drv_probe,
	.remove = __devexit_p(ux500_pcm_drv_remove),
};

static int __init ux500_pcm_drv_init(void)
{
	pr_debug("%s: Register ux500-pcm platform driver.\n", __func__);

	return platform_driver_register(&ux500_pcm_driver);
}

static void __exit ux500_pcm_drv_exit(void)
{
	pr_debug("%s: Unregister ux500-pcm platform driver.\n", __func__);

	platform_driver_unregister(&ux500_pcm_driver);
}

module_init(ux500_pcm_drv_init);
module_exit(ux500_pcm_drv_exit);

MODULE_LICENSE("GPL");