// SPDX-License-Identifier: GPL-2.0
//
// Socionext UniPhier AIO Compress Audio driver.
//
// Copyright (c) 2017-2018 Socionext Inc.
//
// 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; version 2
// of the License.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, see <http://www.gnu.org/licenses/>.

#include <linux/bitfield.h>
#include <linux/circ_buf.h>
#include <linux/dma-mapping.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/soc.h>

#include "aio.h"

static int uniphier_aio_compr_prepare(struct snd_compr_stream *cstream);
static int uniphier_aio_compr_hw_free(struct snd_compr_stream *cstream);

static int uniphier_aio_comprdma_new(struct snd_soc_pcm_runtime *rtd)
{
	struct snd_compr *compr = rtd->compr;
	struct device *dev = compr->card->dev;
	struct uniphier_aio *aio = uniphier_priv(rtd->cpu_dai);
	struct uniphier_aio_sub *sub = &aio->sub[compr->direction];
	size_t size = AUD_RING_SIZE;
	int dma_dir = DMA_FROM_DEVICE, ret;

	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(33));
	if (ret)
		return ret;

	sub->compr_area = kzalloc(size, GFP_KERNEL);
	if (!sub->compr_area)
		return -ENOMEM;

	if (sub->swm->dir == PORT_DIR_OUTPUT)
		dma_dir = DMA_TO_DEVICE;

	sub->compr_addr = dma_map_single(dev, sub->compr_area, size, dma_dir);
	if (dma_mapping_error(dev, sub->compr_addr)) {
		kfree(sub->compr_area);
		sub->compr_area = NULL;

		return -ENOMEM;
	}

	sub->compr_bytes = size;

	return 0;
}

static int uniphier_aio_comprdma_free(struct snd_soc_pcm_runtime *rtd)
{
	struct snd_compr *compr = rtd->compr;
	struct device *dev = compr->card->dev;
	struct uniphier_aio *aio = uniphier_priv(rtd->cpu_dai);
	struct uniphier_aio_sub *sub = &aio->sub[compr->direction];
	int dma_dir = DMA_FROM_DEVICE;

	if (sub->swm->dir == PORT_DIR_OUTPUT)
		dma_dir = DMA_TO_DEVICE;

	dma_unmap_single(dev, sub->compr_addr, sub->compr_bytes, dma_dir);
	kfree(sub->compr_area);
	sub->compr_area = NULL;

	return 0;
}

static int uniphier_aio_compr_open(struct snd_compr_stream *cstream)
{
	struct snd_soc_pcm_runtime *rtd = cstream->private_data;
	struct uniphier_aio *aio = uniphier_priv(rtd->cpu_dai);
	struct uniphier_aio_sub *sub = &aio->sub[cstream->direction];
	int ret;

	if (sub->cstream)
		return -EBUSY;

	sub->cstream = cstream;
	sub->pass_through = 1;
	sub->use_mmap = false;

	ret = uniphier_aio_comprdma_new(rtd);
	if (ret)
		return ret;

	ret = aio_init(sub);
	if (ret)
		return ret;

	return 0;
}

static int uniphier_aio_compr_free(struct snd_compr_stream *cstream)
{
	struct snd_soc_pcm_runtime *rtd = cstream->private_data;
	struct uniphier_aio *aio = uniphier_priv(rtd->cpu_dai);
	struct uniphier_aio_sub *sub = &aio->sub[cstream->direction];
	int ret;

	ret = uniphier_aio_compr_hw_free(cstream);
	if (ret)
		return ret;
	ret = uniphier_aio_comprdma_free(rtd);
	if (ret)
		return ret;

	sub->cstream = NULL;

	return 0;
}

static int uniphier_aio_compr_get_params(struct snd_compr_stream *cstream,
					 struct snd_codec *params)
{
	struct snd_soc_pcm_runtime *rtd = cstream->private_data;
	struct uniphier_aio *aio = uniphier_priv(rtd->cpu_dai);
	struct uniphier_aio_sub *sub = &aio->sub[cstream->direction];

	*params = sub->cparams.codec;

	return 0;
}

static int uniphier_aio_compr_set_params(struct snd_compr_stream *cstream,
					 struct snd_compr_params *params)
{
	struct snd_soc_pcm_runtime *rtd = cstream->private_data;
	struct uniphier_aio *aio = uniphier_priv(rtd->cpu_dai);
	struct uniphier_aio_sub *sub = &aio->sub[cstream->direction];
	struct device *dev = &aio->chip->pdev->dev;
	int ret;

	if (params->codec.id != SND_AUDIOCODEC_IEC61937) {
		dev_err(dev, "Codec ID is not supported(%d)\n",
			params->codec.id);
		return -EINVAL;
	}
	if (params->codec.profile != SND_AUDIOPROFILE_IEC61937_SPDIF) {
		dev_err(dev, "Codec profile is not supported(%d)\n",
			params->codec.profile);
		return -EINVAL;
	}

	/* IEC frame type will be changed after received valid data */
	sub->iec_pc = IEC61937_PC_AAC;

	sub->cparams = *params;
	sub->setting = 1;

	aio_port_reset(sub);
	aio_src_reset(sub);

	ret = uniphier_aio_compr_prepare(cstream);
	if (ret)
		return ret;

	return 0;
}

static int uniphier_aio_compr_hw_free(struct snd_compr_stream *cstream)
{
	struct snd_soc_pcm_runtime *rtd = cstream->private_data;
	struct uniphier_aio *aio = uniphier_priv(rtd->cpu_dai);
	struct uniphier_aio_sub *sub = &aio->sub[cstream->direction];

	sub->setting = 0;

	return 0;
}

static int uniphier_aio_compr_prepare(struct snd_compr_stream *cstream)
{
	struct snd_soc_pcm_runtime *rtd = cstream->private_data;
	struct snd_compr_runtime *runtime = cstream->runtime;
	struct uniphier_aio *aio = uniphier_priv(rtd->cpu_dai);
	struct uniphier_aio_sub *sub = &aio->sub[cstream->direction];
	int bytes = runtime->fragment_size;
	unsigned long flags;
	int ret;

	ret = aiodma_ch_set_param(sub);
	if (ret)
		return ret;

	spin_lock_irqsave(&sub->lock, flags);
	ret = aiodma_rb_set_buffer(sub, sub->compr_addr,
				   sub->compr_addr + sub->compr_bytes,
				   bytes);
	spin_unlock_irqrestore(&sub->lock, flags);
	if (ret)
		return ret;

	ret = aio_port_set_param(sub, sub->pass_through, &sub->params);
	if (ret)
		return ret;
	ret = aio_oport_set_stream_type(sub, sub->iec_pc);
	if (ret)
		return ret;
	aio_port_set_enable(sub, 1);

	ret = aio_if_set_param(sub, sub->pass_through);
	if (ret)
		return ret;

	return 0;
}

static int uniphier_aio_compr_trigger(struct snd_compr_stream *cstream,
				      int cmd)
{
	struct snd_soc_pcm_runtime *rtd = cstream->private_data;
	struct snd_compr_runtime *runtime = cstream->runtime;
	struct uniphier_aio *aio = uniphier_priv(rtd->cpu_dai);
	struct uniphier_aio_sub *sub = &aio->sub[cstream->direction];
	struct device *dev = &aio->chip->pdev->dev;
	int bytes = runtime->fragment_size, ret = 0;
	unsigned long flags;

	spin_lock_irqsave(&sub->lock, flags);
	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
		aiodma_rb_sync(sub, sub->compr_addr, sub->compr_bytes, bytes);
		aiodma_ch_set_enable(sub, 1);
		sub->running = 1;

		break;
	case SNDRV_PCM_TRIGGER_STOP:
		sub->running = 0;
		aiodma_ch_set_enable(sub, 0);

		break;
	default:
		dev_warn(dev, "Unknown trigger(%d)\n", cmd);
		ret = -EINVAL;
	}
	spin_unlock_irqrestore(&sub->lock, flags);

	return ret;
}

static int uniphier_aio_compr_pointer(struct snd_compr_stream *cstream,
				      struct snd_compr_tstamp *tstamp)
{
	struct snd_soc_pcm_runtime *rtd = cstream->private_data;
	struct snd_compr_runtime *runtime = cstream->runtime;
	struct uniphier_aio *aio = uniphier_priv(rtd->cpu_dai);
	struct uniphier_aio_sub *sub = &aio->sub[cstream->direction];
	int bytes = runtime->fragment_size;
	unsigned long flags;
	u32 pos;

	spin_lock_irqsave(&sub->lock, flags);

	aiodma_rb_sync(sub, sub->compr_addr, sub->compr_bytes, bytes);

	if (sub->swm->dir == PORT_DIR_OUTPUT) {
		pos = sub->rd_offs;
		/* Size of AIO output format is double of IEC61937 */
		tstamp->copied_total = sub->rd_total / 2;
	} else {
		pos = sub->wr_offs;
		tstamp->copied_total = sub->rd_total;
	}
	tstamp->byte_offset = pos;

	spin_unlock_irqrestore(&sub->lock, flags);

	return 0;
}

static int aio_compr_send_to_hw(struct uniphier_aio_sub *sub,
				char __user *buf, size_t dstsize)
{
	u32 __user *srcbuf = (u32 __user *)buf;
	u32 *dstbuf = (u32 *)(sub->compr_area + sub->wr_offs);
	int src = 0, dst = 0, ret;
	u32 frm, frm_a, frm_b;

	while (dstsize > 0) {
		ret = get_user(frm, srcbuf + src);
		if (ret)
			return ret;
		src++;

		frm_a = frm & 0xffff;
		frm_b = (frm >> 16) & 0xffff;

		if (frm == IEC61937_HEADER_SIGN) {
			frm_a |= 0x01000000;

			/* Next data is Pc and Pd */
			sub->iec_header = true;
		} else {
			u16 pc = be16_to_cpu((__be16)frm_a);

			if (sub->iec_header && sub->iec_pc != pc) {
				/* Force overwrite IEC frame type */
				sub->iec_pc = pc;
				ret = aio_oport_set_stream_type(sub, pc);
				if (ret)
					return ret;
			}
			sub->iec_header = false;
		}
		dstbuf[dst++] = frm_a;
		dstbuf[dst++] = frm_b;

		dstsize -= sizeof(u32) * 2;
	}

	return 0;
}

static int uniphier_aio_compr_copy(struct snd_compr_stream *cstream,
				   char __user *buf, size_t count)
{
	struct snd_soc_pcm_runtime *rtd = cstream->private_data;
	struct snd_compr_runtime *runtime = cstream->runtime;
	struct device *carddev = rtd->compr->card->dev;
	struct uniphier_aio *aio = uniphier_priv(rtd->cpu_dai);
	struct uniphier_aio_sub *sub = &aio->sub[cstream->direction];
	size_t cnt = min_t(size_t, count, aio_rb_space_to_end(sub) / 2);
	int bytes = runtime->fragment_size;
	unsigned long flags;
	size_t s;
	int ret;

	if (cnt < sizeof(u32))
		return 0;

	if (sub->swm->dir == PORT_DIR_OUTPUT) {
		dma_addr_t dmapos = sub->compr_addr + sub->wr_offs;

		/* Size of AIO output format is double of IEC61937 */
		s = cnt * 2;

		dma_sync_single_for_cpu(carddev, dmapos, s, DMA_TO_DEVICE);
		ret = aio_compr_send_to_hw(sub, buf, s);
		dma_sync_single_for_device(carddev, dmapos, s, DMA_TO_DEVICE);
	} else {
		dma_addr_t dmapos = sub->compr_addr + sub->rd_offs;

		s = cnt;

		dma_sync_single_for_cpu(carddev, dmapos, s, DMA_FROM_DEVICE);
		ret = copy_to_user(buf, sub->compr_area + sub->rd_offs, s);
		dma_sync_single_for_device(carddev, dmapos, s, DMA_FROM_DEVICE);
	}
	if (ret)
		return -EFAULT;

	spin_lock_irqsave(&sub->lock, flags);

	sub->threshold = 2 * bytes;
	aiodma_rb_set_threshold(sub, sub->compr_bytes, 2 * bytes);

	if (sub->swm->dir == PORT_DIR_OUTPUT) {
		sub->wr_offs += s;
		if (sub->wr_offs >= sub->compr_bytes)
			sub->wr_offs -= sub->compr_bytes;
	} else {
		sub->rd_offs += s;
		if (sub->rd_offs >= sub->compr_bytes)
			sub->rd_offs -= sub->compr_bytes;
	}
	aiodma_rb_sync(sub, sub->compr_addr, sub->compr_bytes, bytes);

	spin_unlock_irqrestore(&sub->lock, flags);

	return cnt;
}

static int uniphier_aio_compr_get_caps(struct snd_compr_stream *cstream,
				       struct snd_compr_caps *caps)
{
	caps->num_codecs = 1;
	caps->min_fragment_size = AUD_MIN_FRAGMENT_SIZE;
	caps->max_fragment_size = AUD_MAX_FRAGMENT_SIZE;
	caps->min_fragments = AUD_MIN_FRAGMENT;
	caps->max_fragments = AUD_MAX_FRAGMENT;
	caps->codecs[0] = SND_AUDIOCODEC_IEC61937;

	return 0;
}

static const struct snd_compr_codec_caps caps_iec = {
	.num_descriptors = 1,
	.descriptor[0].max_ch = 8,
	.descriptor[0].num_sample_rates = 0,
	.descriptor[0].num_bitrates = 0,
	.descriptor[0].profiles = SND_AUDIOPROFILE_IEC61937_SPDIF,
	.descriptor[0].modes = SND_AUDIOMODE_IEC_AC3 |
				SND_AUDIOMODE_IEC_MPEG1 |
				SND_AUDIOMODE_IEC_MP3 |
				SND_AUDIOMODE_IEC_DTS,
	.descriptor[0].formats = 0,
};

static int uniphier_aio_compr_get_codec_caps(struct snd_compr_stream *stream,
					     struct snd_compr_codec_caps *codec)
{
	if (codec->codec == SND_AUDIOCODEC_IEC61937)
		*codec = caps_iec;
	else
		return -EINVAL;

	return 0;
}

const struct snd_compr_ops uniphier_aio_compr_ops = {
	.open           = uniphier_aio_compr_open,
	.free           = uniphier_aio_compr_free,
	.get_params     = uniphier_aio_compr_get_params,
	.set_params     = uniphier_aio_compr_set_params,
	.trigger        = uniphier_aio_compr_trigger,
	.pointer        = uniphier_aio_compr_pointer,
	.copy           = uniphier_aio_compr_copy,
	.get_caps       = uniphier_aio_compr_get_caps,
	.get_codec_caps = uniphier_aio_compr_get_codec_caps,
};