ubuntu-linux-kernel/drivers/media/platform/sti/delta/delta-v4l2.c

/*
 * Copyright (C) STMicroelectronics SA 2015
 * Authors: Hugues Fruchet <hugues.fruchet@st.com>
 *          Jean-Christophe Trotin <jean-christophe.trotin@st.com>
 *          for STMicroelectronics.
 * License terms:  GNU General Public License (GPL), version 2
 */

#include <linux/clk.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>

#include <media/v4l2-ioctl.h>
#include <media/v4l2-event.h>
#include <media/videobuf2-dma-contig.h>

#include "delta.h"
#include "delta-debug.h"
#include "delta-ipc.h"

#define DELTA_NAME	"st-delta"

#define DELTA_PREFIX "[---:----]"

#define to_ctx(__fh) container_of(__fh, struct delta_ctx, fh)
#define to_au(__vbuf) container_of(__vbuf, struct delta_au, vbuf)
#define to_frame(__vbuf) container_of(__vbuf, struct delta_frame, vbuf)

#define call_dec_op(dec, op, args...)\
		((dec && (dec)->op) ? (dec)->op(args) : 0)

/* registry of available decoders */
static const struct delta_dec *delta_decoders[] = {
#ifdef CONFIG_VIDEO_STI_DELTA_MJPEG
	&mjpegdec,
#endif
};

static inline int frame_size(u32 w, u32 h, u32 fmt)
{
	switch (fmt) {
	case V4L2_PIX_FMT_NV12:
		return (w * h * 3) / 2;
	default:
		return 0;
	}
}

static inline int frame_stride(u32 w, u32 fmt)
{
	switch (fmt) {
	case V4L2_PIX_FMT_NV12:
		return w;
	default:
		return 0;
	}
}

static void dump_au(struct delta_ctx *ctx, struct delta_au *au)
{
	struct delta_dev *delta = ctx->dev;
	u32 size = 10;	/* dump first & last 10 bytes */
	u8 *data = (u8 *)(au->vaddr);

	if (au->size <= (size * 2))
		dev_dbg(delta->dev, "%s dump au[%d] dts=%lld size=%d data=%*ph\n",
			ctx->name, au->vbuf.vb2_buf.index, au->dts, au->size,
			au->size, data);
	else
		dev_dbg(delta->dev, "%s dump au[%d] dts=%lld size=%d data=%*ph..%*ph\n",
			ctx->name, au->vbuf.vb2_buf.index, au->dts, au->size,
			size, data, size, data + au->size - size);
}

static void dump_frame(struct delta_ctx *ctx, struct delta_frame *frame)
{
	struct delta_dev *delta = ctx->dev;
	u32 size = 10;	/* dump first 10 bytes */
	u8 *data = (u8 *)(frame->vaddr);

	dev_dbg(delta->dev, "%s dump frame[%d] dts=%lld type=%s field=%s data=%*ph\n",
		ctx->name, frame->index, frame->dts,
		frame_type_str(frame->flags),
		frame_field_str(frame->field),
		size, data);
}

static void delta_au_done(struct delta_ctx *ctx, struct delta_au *au, int err)
{
	struct vb2_v4l2_buffer *vbuf;

	vbuf = &au->vbuf;
	vbuf->sequence = ctx->au_num++;
	v4l2_m2m_buf_done(vbuf, err ? VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
}

static void delta_frame_done(struct delta_ctx *ctx, struct delta_frame *frame,
			     int err)
{
	struct vb2_v4l2_buffer *vbuf;

	dump_frame(ctx, frame);

	/* decoded frame is now output to user */
	frame->state |= DELTA_FRAME_OUT;

	vbuf = &frame->vbuf;
	vbuf->sequence = ctx->frame_num++;
	v4l2_m2m_buf_done(vbuf, err ? VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);

	if (frame->info.size) /* ignore EOS */
		ctx->output_frames++;
}

static void requeue_free_frames(struct delta_ctx *ctx)
{
	struct vb2_v4l2_buffer *vbuf;
	struct delta_frame *frame;
	unsigned int i;

	/* requeue all free frames */
	for (i = 0; i < ctx->nb_of_frames; i++) {
		frame = ctx->frames[i];
		if (frame->state == DELTA_FRAME_FREE) {
			vbuf = &frame->vbuf;
			v4l2_m2m_buf_queue(ctx->fh.m2m_ctx, vbuf);
			frame->state = DELTA_FRAME_M2M;
		}
	}
}

static int delta_recycle(struct delta_ctx *ctx, struct delta_frame *frame)
{
	const struct delta_dec *dec = ctx->dec;

	/* recycle frame on decoder side */
	call_dec_op(dec, recycle, ctx, frame);

	/* this frame is no more output */
	frame->state &= ~DELTA_FRAME_OUT;

	/* requeue free frame */
	if (frame->state == DELTA_FRAME_FREE) {
		struct vb2_v4l2_buffer *vbuf = &frame->vbuf;

		v4l2_m2m_buf_queue(ctx->fh.m2m_ctx, vbuf);
		frame->state = DELTA_FRAME_M2M;
	}

	/* reset other frame fields */
	frame->flags = 0;
	frame->dts = 0;

	return 0;
}

static void delta_push_dts(struct delta_ctx *ctx, u64 val)
{
	struct delta_dts *dts;

	dts = kzalloc(sizeof(*dts), GFP_KERNEL);
	if (!dts)
		return;

	INIT_LIST_HEAD(&dts->list);

	/*
	 * protected by global lock acquired
	 * by V4L2 when calling delta_vb2_au_queue
	 */
	dts->val = val;
	list_add_tail(&dts->list, &ctx->dts);
}

static void delta_pop_dts(struct delta_ctx *ctx, u64 *val)
{
	struct delta_dev *delta = ctx->dev;
	struct delta_dts *dts;

	/*
	 * protected by global lock acquired
	 * by V4L2 when calling delta_vb2_au_queue
	 */
	if (list_empty(&ctx->dts)) {
		dev_warn(delta->dev, "%s no dts to pop ... output dts = 0\n",
			 ctx->name);
		*val = 0;
		return;
	}

	dts = list_first_entry(&ctx->dts, struct delta_dts, list);
	list_del(&dts->list);

	*val = dts->val;

	kfree(dts);
}

static void delta_flush_dts(struct delta_ctx *ctx)
{
	struct delta_dts *dts;
	struct delta_dts *next;

	/*
	 * protected by global lock acquired
	 * by V4L2 when calling delta_vb2_au_queue
	 */

	/* free all pending dts */
	list_for_each_entry_safe(dts, next, &ctx->dts, list)
		kfree(dts);

	/* reset list */
	INIT_LIST_HEAD(&ctx->dts);
}

static inline int frame_alignment(u32 fmt)
{
	switch (fmt) {
	case V4L2_PIX_FMT_NV12:
	case V4L2_PIX_FMT_NV21:
		/* multiple of 2 */
		return 2;
	default:
		return 1;
	}
}

static inline int estimated_au_size(u32 w, u32 h)
{
	/*
	 * for a MJPEG stream encoded from YUV422 pixel format,
	 * assuming a compression ratio of 2, the maximum size
	 * of an access unit is (width x height x 2) / 2,
	 * so (width x height)
	 */
	return (w * h);
}

static void set_default_params(struct delta_ctx *ctx)
{
	struct delta_frameinfo *frameinfo = &ctx->frameinfo;
	struct delta_streaminfo *streaminfo = &ctx->streaminfo;

	memset(frameinfo, 0, sizeof(*frameinfo));
	frameinfo->pixelformat = V4L2_PIX_FMT_NV12;
	frameinfo->width = DELTA_DEFAULT_WIDTH;
	frameinfo->height = DELTA_DEFAULT_HEIGHT;
	frameinfo->aligned_width = ALIGN(frameinfo->width,
					 DELTA_WIDTH_ALIGNMENT);
	frameinfo->aligned_height = ALIGN(frameinfo->height,
					  DELTA_HEIGHT_ALIGNMENT);
	frameinfo->size = frame_size(frameinfo->aligned_width,
				     frameinfo->aligned_height,
				     frameinfo->pixelformat);
	frameinfo->field = V4L2_FIELD_NONE;
	frameinfo->colorspace = V4L2_COLORSPACE_REC709;
	frameinfo->xfer_func = V4L2_XFER_FUNC_DEFAULT;
	frameinfo->ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
	frameinfo->quantization = V4L2_QUANTIZATION_DEFAULT;

	memset(streaminfo, 0, sizeof(*streaminfo));
	streaminfo->streamformat = DELTA_DEFAULT_STREAMFORMAT;
	streaminfo->width = DELTA_DEFAULT_WIDTH;
	streaminfo->height = DELTA_DEFAULT_HEIGHT;
	streaminfo->field = V4L2_FIELD_NONE;
	streaminfo->colorspace = V4L2_COLORSPACE_REC709;
	streaminfo->xfer_func = V4L2_XFER_FUNC_DEFAULT;
	streaminfo->ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
	streaminfo->quantization = V4L2_QUANTIZATION_DEFAULT;

	ctx->max_au_size = estimated_au_size(streaminfo->width,
					     streaminfo->height);
}

static const struct delta_dec *delta_find_decoder(struct delta_ctx *ctx,
						  u32 streamformat,
						  u32 pixelformat)
{
	struct delta_dev *delta = ctx->dev;
	const struct delta_dec *dec;
	unsigned int i;

	for (i = 0; i < delta->nb_of_decoders; i++) {
		dec = delta->decoders[i];
		if ((dec->pixelformat == pixelformat) &&
		    (dec->streamformat == streamformat))
			return dec;
	}

	return NULL;
}

static void register_format(u32 format, u32 formats[], u32 *nb_of_formats)
{
	u32 i;

	for (i = 0; i < *nb_of_formats; i++) {
		if (format == formats[i])
			return;
	}

	formats[(*nb_of_formats)++] = format;
}

static void register_formats(struct delta_dev *delta)
{
	unsigned int i;

	for (i = 0; i < delta->nb_of_decoders; i++) {
		register_format(delta->decoders[i]->pixelformat,
				delta->pixelformats,
				&delta->nb_of_pixelformats);

		register_format(delta->decoders[i]->streamformat,
				delta->streamformats,
				&delta->nb_of_streamformats);
	}
}

static void register_decoders(struct delta_dev *delta)
{
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(delta_decoders); i++) {
		if (delta->nb_of_decoders >= DELTA_MAX_DECODERS) {
			dev_dbg(delta->dev,
				"%s failed to register %s decoder (%d maximum reached)\n",
				DELTA_PREFIX, delta_decoders[i]->name,
				DELTA_MAX_DECODERS);
			return;
		}

		delta->decoders[delta->nb_of_decoders++] = delta_decoders[i];
		dev_info(delta->dev, "%s %s decoder registered\n",
			 DELTA_PREFIX, delta_decoders[i]->name);
	}
}

static void delta_lock(void *priv)
{
	struct delta_ctx *ctx = priv;
	struct delta_dev *delta = ctx->dev;

	mutex_lock(&delta->lock);
}

static void delta_unlock(void *priv)
{
	struct delta_ctx *ctx = priv;
	struct delta_dev *delta = ctx->dev;

	mutex_unlock(&delta->lock);
}

static int delta_open_decoder(struct delta_ctx *ctx, u32 streamformat,
			      u32 pixelformat, const struct delta_dec **pdec)
{
	struct delta_dev *delta = ctx->dev;
	const struct delta_dec *dec;
	int ret;

	dec = delta_find_decoder(ctx, streamformat, ctx->frameinfo.pixelformat);
	if (!dec) {
		dev_err(delta->dev, "%s no decoder found matching %4.4s => %4.4s\n",
			ctx->name, (char *)&streamformat, (char *)&pixelformat);
		return -EINVAL;
	}

	dev_dbg(delta->dev, "%s one decoder matching %4.4s => %4.4s\n",
		ctx->name, (char *)&streamformat, (char *)&pixelformat);

	/* update instance name */
	snprintf(ctx->name, sizeof(ctx->name), "[%3d:%4.4s]",
		 delta->instance_id, (char *)&streamformat);

	/* open decoder instance */
	ret = call_dec_op(dec, open, ctx);
	if (ret) {
		dev_err(delta->dev, "%s failed to open decoder instance (%d)\n",
			ctx->name, ret);
		return ret;
	}

	dev_dbg(delta->dev, "%s %s decoder opened\n", ctx->name, dec->name);

	*pdec = dec;

	return ret;
}

/*
 * V4L2 ioctl operations
 */

static int delta_querycap(struct file *file, void *priv,
			  struct v4l2_capability *cap)
{
	struct delta_ctx *ctx = to_ctx(file->private_data);
	struct delta_dev *delta = ctx->dev;

	strlcpy(cap->driver, DELTA_NAME, sizeof(cap->driver));
	strlcpy(cap->card, delta->vdev->name, sizeof(cap->card));
	snprintf(cap->bus_info, sizeof(cap->bus_info), "platform:%s",
		 delta->pdev->name);

	return 0;
}

static int delta_enum_fmt_stream(struct file *file, void *priv,
				 struct v4l2_fmtdesc *f)
{
	struct delta_ctx *ctx = to_ctx(file->private_data);
	struct delta_dev *delta = ctx->dev;

	if (unlikely(f->index >= delta->nb_of_streamformats))
		return -EINVAL;

	f->pixelformat = delta->streamformats[f->index];

	return 0;
}

static int delta_enum_fmt_frame(struct file *file, void *priv,
				struct v4l2_fmtdesc *f)
{
	struct delta_ctx *ctx = to_ctx(file->private_data);
	struct delta_dev *delta = ctx->dev;

	if (unlikely(f->index >= delta->nb_of_pixelformats))
		return -EINVAL;

	f->pixelformat = delta->pixelformats[f->index];

	return 0;
}

static int delta_g_fmt_stream(struct file *file, void *fh,
			      struct v4l2_format *f)
{
	struct delta_ctx *ctx = to_ctx(file->private_data);
	struct delta_dev *delta = ctx->dev;
	struct v4l2_pix_format *pix = &f->fmt.pix;
	struct delta_streaminfo *streaminfo = &ctx->streaminfo;
	unsigned char str[100] = "";

	if (!(ctx->flags & DELTA_FLAG_STREAMINFO))
		dev_dbg(delta->dev,
			"%s V4L2 GET_FMT (OUTPUT): no stream information available, default to %s\n",
			ctx->name,
			delta_streaminfo_str(streaminfo, str, sizeof(str)));

	pix->pixelformat = streaminfo->streamformat;
	pix->width = streaminfo->width;
	pix->height = streaminfo->height;
	pix->field = streaminfo->field;
	pix->bytesperline = 0;
	pix->sizeimage = ctx->max_au_size;
	pix->colorspace = streaminfo->colorspace;
	pix->xfer_func = streaminfo->xfer_func;
	pix->ycbcr_enc = streaminfo->ycbcr_enc;
	pix->quantization = streaminfo->quantization;

	return 0;
}

static int delta_g_fmt_frame(struct file *file, void *fh, struct v4l2_format *f)
{
	struct delta_ctx *ctx = to_ctx(file->private_data);
	struct delta_dev *delta = ctx->dev;
	struct v4l2_pix_format *pix = &f->fmt.pix;
	struct delta_frameinfo *frameinfo = &ctx->frameinfo;
	struct delta_streaminfo *streaminfo = &ctx->streaminfo;
	unsigned char str[100] = "";

	if (!(ctx->flags & DELTA_FLAG_FRAMEINFO))
		dev_dbg(delta->dev,
			"%s V4L2 GET_FMT (CAPTURE): no frame information available, default to %s\n",
			ctx->name,
			delta_frameinfo_str(frameinfo, str, sizeof(str)));

	pix->pixelformat = frameinfo->pixelformat;
	pix->width = frameinfo->aligned_width;
	pix->height = frameinfo->aligned_height;
	pix->field = frameinfo->field;
	pix->bytesperline = frame_stride(frameinfo->aligned_width,
					       frameinfo->pixelformat);
	pix->sizeimage = frameinfo->size;

	if (ctx->flags & DELTA_FLAG_STREAMINFO) {
		/* align colorspace & friends on stream ones if any set */
		frameinfo->colorspace = streaminfo->colorspace;
		frameinfo->xfer_func = streaminfo->xfer_func;
		frameinfo->ycbcr_enc = streaminfo->ycbcr_enc;
		frameinfo->quantization = streaminfo->quantization;
	}
	pix->colorspace = frameinfo->colorspace;
	pix->xfer_func = frameinfo->xfer_func;
	pix->ycbcr_enc = frameinfo->ycbcr_enc;
	pix->quantization = frameinfo->quantization;

	return 0;
}

static int delta_try_fmt_stream(struct file *file, void *priv,
				struct v4l2_format *f)
{
	struct delta_ctx *ctx = to_ctx(file->private_data);
	struct delta_dev *delta = ctx->dev;
	struct v4l2_pix_format *pix = &f->fmt.pix;
	u32 streamformat = pix->pixelformat;
	const struct delta_dec *dec;
	u32 width, height;
	u32 au_size;

	dec = delta_find_decoder(ctx, streamformat, ctx->frameinfo.pixelformat);
	if (!dec) {
		dev_dbg(delta->dev,
			"%s V4L2 TRY_FMT (OUTPUT): unsupported format %4.4s\n",
			ctx->name, (char *)&pix->pixelformat);
		return -EINVAL;
	}

	/* adjust width & height */
	width = pix->width;
	height = pix->height;
	v4l_bound_align_image
		(&pix->width,
		 DELTA_MIN_WIDTH,
		 dec->max_width ? dec->max_width : DELTA_MAX_WIDTH,
		 0,
		 &pix->height,
		 DELTA_MIN_HEIGHT,
		 dec->max_height ? dec->max_height : DELTA_MAX_HEIGHT,
		 0, 0);

	if ((pix->width != width) || (pix->height != height))
		dev_dbg(delta->dev,
			"%s V4L2 TRY_FMT (OUTPUT): resolution updated %dx%d -> %dx%d to fit min/max/alignment\n",
			ctx->name, width, height,
			pix->width, pix->height);

	au_size = estimated_au_size(pix->width, pix->height);
	if (pix->sizeimage < au_size) {
		dev_dbg(delta->dev,
			"%s V4L2 TRY_FMT (OUTPUT): size updated %d -> %d to fit estimated size\n",
			ctx->name, pix->sizeimage, au_size);
		pix->sizeimage = au_size;
	}

	pix->bytesperline = 0;

	if (pix->field == V4L2_FIELD_ANY)
		pix->field = V4L2_FIELD_NONE;

	return 0;
}

static int delta_try_fmt_frame(struct file *file, void *priv,
			       struct v4l2_format *f)
{
	struct delta_ctx *ctx = to_ctx(file->private_data);
	struct delta_dev *delta = ctx->dev;
	struct v4l2_pix_format *pix = &f->fmt.pix;
	u32 pixelformat = pix->pixelformat;
	const struct delta_dec *dec;
	u32 width, height;

	dec = delta_find_decoder(ctx, ctx->streaminfo.streamformat,
				 pixelformat);
	if (!dec) {
		dev_dbg(delta->dev,
			"%s V4L2 TRY_FMT (CAPTURE): unsupported format %4.4s\n",
			ctx->name, (char *)&pixelformat);
		return -EINVAL;
	}

	/* adjust width & height */
	width = pix->width;
	height = pix->height;
	v4l_bound_align_image(&pix->width,
			      DELTA_MIN_WIDTH, DELTA_MAX_WIDTH,
			      frame_alignment(pixelformat) - 1,
			      &pix->height,
			      DELTA_MIN_HEIGHT, DELTA_MAX_HEIGHT,
			      frame_alignment(pixelformat) - 1, 0);

	if ((pix->width != width) || (pix->height != height))
		dev_dbg(delta->dev,
			"%s V4L2 TRY_FMT (CAPTURE): resolution updated %dx%d -> %dx%d to fit min/max/alignment\n",
			ctx->name, width, height, pix->width, pix->height);

	/* default decoder alignment constraint */
	width = ALIGN(pix->width, DELTA_WIDTH_ALIGNMENT);
	height = ALIGN(pix->height, DELTA_HEIGHT_ALIGNMENT);
	if ((pix->width != width) || (pix->height != height))
		dev_dbg(delta->dev,
			"%s V4L2 TRY_FMT (CAPTURE): resolution updated %dx%d -> %dx%d to fit decoder alignment\n",
			ctx->name, width, height, pix->width, pix->height);

	if (!pix->colorspace) {
		pix->colorspace = V4L2_COLORSPACE_REC709;
		pix->xfer_func = V4L2_XFER_FUNC_DEFAULT;
		pix->ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
		pix->quantization = V4L2_QUANTIZATION_DEFAULT;
	}

	pix->width = width;
	pix->height = height;
	pix->bytesperline = frame_stride(pix->width, pixelformat);
	pix->sizeimage = frame_size(pix->width, pix->height, pixelformat);

	if (pix->field == V4L2_FIELD_ANY)
		pix->field = V4L2_FIELD_NONE;

	return 0;
}

static int delta_s_fmt_stream(struct file *file, void *fh,
			      struct v4l2_format *f)
{
	struct delta_ctx *ctx = to_ctx(file->private_data);
	struct delta_dev *delta = ctx->dev;
	struct vb2_queue *vq;
	struct v4l2_pix_format *pix = &f->fmt.pix;
	int ret;

	ret = delta_try_fmt_stream(file, fh, f);
	if (ret) {
		dev_dbg(delta->dev,
			"%s V4L2 S_FMT (OUTPUT): unsupported format %4.4s\n",
			ctx->name, (char *)&pix->pixelformat);
		return ret;
	}

	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
	if (vb2_is_streaming(vq)) {
		dev_dbg(delta->dev, "%s V4L2 S_FMT (OUTPUT): queue busy\n",
			ctx->name);
		return -EBUSY;
	}

	ctx->max_au_size = pix->sizeimage;
	ctx->streaminfo.width = pix->width;
	ctx->streaminfo.height = pix->height;
	ctx->streaminfo.streamformat = pix->pixelformat;
	ctx->streaminfo.colorspace = pix->colorspace;
	ctx->streaminfo.xfer_func = pix->xfer_func;
	ctx->streaminfo.ycbcr_enc = pix->ycbcr_enc;
	ctx->streaminfo.quantization = pix->quantization;
	ctx->flags |= DELTA_FLAG_STREAMINFO;

	return 0;
}

static int delta_s_fmt_frame(struct file *file, void *fh, struct v4l2_format *f)
{
	struct delta_ctx *ctx = to_ctx(file->private_data);
	struct delta_dev *delta = ctx->dev;
	const struct delta_dec *dec = ctx->dec;
	struct v4l2_pix_format *pix = &f->fmt.pix;
	struct delta_frameinfo frameinfo;
	unsigned char str[100] = "";
	struct vb2_queue *vq;
	int ret;

	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
	if (vb2_is_streaming(vq)) {
		dev_dbg(delta->dev, "%s V4L2 S_FMT (CAPTURE): queue busy\n",
			ctx->name);
		return -EBUSY;
	}

	if (ctx->state < DELTA_STATE_READY) {
		/*
		 * decoder not yet opened and valid stream header not found,
		 * could not negotiate format with decoder, check at least
		 * pixel format & negotiate resolution boundaries
		 * and alignment...
		 */
		ret = delta_try_fmt_frame(file, fh, f);
		if (ret) {
			dev_dbg(delta->dev,
				"%s V4L2 S_FMT (CAPTURE): unsupported format %4.4s\n",
				ctx->name, (char *)&pix->pixelformat);
			return ret;
		}

		return 0;
	}

	/* set frame information to decoder */
	memset(&frameinfo, 0, sizeof(frameinfo));
	frameinfo.pixelformat = pix->pixelformat;
	frameinfo.width = pix->width;
	frameinfo.height = pix->height;
	frameinfo.aligned_width = pix->width;
	frameinfo.aligned_height = pix->height;
	frameinfo.size = pix->sizeimage;
	frameinfo.field = pix->field;
	frameinfo.colorspace = pix->colorspace;
	frameinfo.xfer_func = pix->xfer_func;
	frameinfo.ycbcr_enc = pix->ycbcr_enc;
	frameinfo.quantization = pix->quantization;
	ret = call_dec_op(dec, set_frameinfo, ctx, &frameinfo);
	if (ret)
		return ret;

	/* then get what decoder can really do */
	ret = call_dec_op(dec, get_frameinfo, ctx, &frameinfo);
	if (ret)
		return ret;

	ctx->flags |= DELTA_FLAG_FRAMEINFO;
	ctx->frameinfo = frameinfo;
	dev_dbg(delta->dev,
		"%s V4L2 SET_FMT (CAPTURE): frameinfo updated to %s\n",
		ctx->name,
		delta_frameinfo_str(&frameinfo, str, sizeof(str)));

	pix->pixelformat = frameinfo.pixelformat;
	pix->width = frameinfo.aligned_width;
	pix->height = frameinfo.aligned_height;
	pix->bytesperline = frame_stride(pix->width, pix->pixelformat);
	pix->sizeimage = frameinfo.size;
	pix->field = frameinfo.field;
	pix->colorspace = frameinfo.colorspace;
	pix->xfer_func = frameinfo.xfer_func;
	pix->ycbcr_enc = frameinfo.ycbcr_enc;
	pix->quantization = frameinfo.quantization;

	return 0;
}

static int delta_g_selection(struct file *file, void *fh,
			     struct v4l2_selection *s)
{
	struct delta_ctx *ctx = to_ctx(fh);
	struct delta_frameinfo *frameinfo = &ctx->frameinfo;
	struct v4l2_rect crop;

	if (s->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
		return -EINVAL;

	if ((ctx->flags & DELTA_FLAG_FRAMEINFO) &&
	    (frameinfo->flags & DELTA_FRAMEINFO_FLAG_CROP)) {
		crop = frameinfo->crop;
	} else {
		/* default to video dimensions */
		crop.left = 0;
		crop.top = 0;
		crop.width = frameinfo->width;
		crop.height = frameinfo->height;
	}

	switch (s->target) {
	case V4L2_SEL_TGT_COMPOSE:
	case V4L2_SEL_TGT_COMPOSE_DEFAULT:
		/* visible area inside video */
		s->r = crop;
		break;
	case V4L2_SEL_TGT_COMPOSE_PADDED:
	case V4L2_SEL_TGT_COMPOSE_BOUNDS:
		/* up to aligned dimensions */
		s->r.left = 0;
		s->r.top = 0;
		s->r.width = frameinfo->aligned_width;
		s->r.height = frameinfo->aligned_height;
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

static void delta_complete_eos(struct delta_ctx *ctx,
			       struct delta_frame *frame)
{
	struct delta_dev *delta = ctx->dev;
	const struct v4l2_event ev = {.type = V4L2_EVENT_EOS};

	/*
	 * Send EOS to user:
	 * - by returning an empty frame flagged to V4L2_BUF_FLAG_LAST
	 * - and then send EOS event
	 */

	/* empty frame */
	frame->info.size = 0;

	/* set the last buffer flag */
	frame->flags |= V4L2_BUF_FLAG_LAST;

	/* release frame to user */
	delta_frame_done(ctx, frame, 0);

	/* send EOS event */
	v4l2_event_queue_fh(&ctx->fh, &ev);

	dev_dbg(delta->dev, "%s EOS completed\n", ctx->name);
}

static int delta_try_decoder_cmd(struct file *file, void *fh,
				 struct v4l2_decoder_cmd *cmd)
{
	if (cmd->cmd != V4L2_DEC_CMD_STOP)
		return -EINVAL;

	if (cmd->flags & V4L2_DEC_CMD_STOP_TO_BLACK)
		return -EINVAL;

	if (!(cmd->flags & V4L2_DEC_CMD_STOP_IMMEDIATELY) &&
	    (cmd->stop.pts != 0))
		return -EINVAL;

	return 0;
}

static int delta_decoder_stop_cmd(struct delta_ctx *ctx, void *fh)
{
	const struct delta_dec *dec = ctx->dec;
	struct delta_dev *delta = ctx->dev;
	struct delta_frame *frame = NULL;
	int ret = 0;

	dev_dbg(delta->dev, "%s EOS received\n", ctx->name);

	if (ctx->state != DELTA_STATE_READY)
		return 0;

	/* drain the decoder */
	call_dec_op(dec, drain, ctx);

	/* release to user drained frames */
	while (1) {
		frame = NULL;
		ret = call_dec_op(dec, get_frame, ctx, &frame);
		if (ret == -ENODATA) {
			/* no more decoded frames */
			break;
		}
		if (frame) {
			dev_dbg(delta->dev, "%s drain frame[%d]\n",
				ctx->name, frame->index);

			/* pop timestamp and mark frame with it */
			delta_pop_dts(ctx, &frame->dts);

			/* release decoded frame to user */
			delta_frame_done(ctx, frame, 0);
		}
	}

	/* try to complete EOS */
	ret = delta_get_free_frame(ctx, &frame);
	if (ret)
		goto delay_eos;

	/* new frame available, EOS can now be completed */
	delta_complete_eos(ctx, frame);

	ctx->state = DELTA_STATE_EOS;

	return 0;

delay_eos:
	/*
	 * EOS completion from driver is delayed because
	 * we don't have a free empty frame available.
	 * EOS completion is so delayed till next frame_queue() call
	 * to be sure to have a free empty frame available.
	 */
	ctx->state = DELTA_STATE_WF_EOS;
	dev_dbg(delta->dev, "%s EOS delayed\n", ctx->name);

	return 0;
}

static int delta_decoder_cmd(struct file *file, void *fh,
			     struct v4l2_decoder_cmd *cmd)
{
	struct delta_ctx *ctx = to_ctx(fh);
	int ret = 0;

	ret = delta_try_decoder_cmd(file, fh, cmd);
	if (ret)
		return ret;

	return delta_decoder_stop_cmd(ctx, fh);
}

static int delta_subscribe_event(struct v4l2_fh *fh,
				 const struct v4l2_event_subscription *sub)
{
	switch (sub->type) {
	case V4L2_EVENT_EOS:
		return v4l2_event_subscribe(fh, sub, 2, NULL);
	default:
		return -EINVAL;
	}

	return 0;
}

/* v4l2 ioctl ops */
static const struct v4l2_ioctl_ops delta_ioctl_ops = {
	.vidioc_querycap = delta_querycap,
	.vidioc_enum_fmt_vid_cap = delta_enum_fmt_frame,
	.vidioc_g_fmt_vid_cap = delta_g_fmt_frame,
	.vidioc_try_fmt_vid_cap = delta_try_fmt_frame,
	.vidioc_s_fmt_vid_cap = delta_s_fmt_frame,
	.vidioc_enum_fmt_vid_out = delta_enum_fmt_stream,
	.vidioc_g_fmt_vid_out = delta_g_fmt_stream,
	.vidioc_try_fmt_vid_out = delta_try_fmt_stream,
	.vidioc_s_fmt_vid_out = delta_s_fmt_stream,
	.vidioc_reqbufs = v4l2_m2m_ioctl_reqbufs,
	.vidioc_create_bufs = v4l2_m2m_ioctl_create_bufs,
	.vidioc_querybuf = v4l2_m2m_ioctl_querybuf,
	.vidioc_expbuf = v4l2_m2m_ioctl_expbuf,
	.vidioc_qbuf = v4l2_m2m_ioctl_qbuf,
	.vidioc_dqbuf = v4l2_m2m_ioctl_dqbuf,
	.vidioc_streamon = v4l2_m2m_ioctl_streamon,
	.vidioc_streamoff = v4l2_m2m_ioctl_streamoff,
	.vidioc_g_selection = delta_g_selection,
	.vidioc_try_decoder_cmd = delta_try_decoder_cmd,
	.vidioc_decoder_cmd = delta_decoder_cmd,
	.vidioc_subscribe_event = delta_subscribe_event,
	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
};

/*
 * mem-to-mem operations
 */

static void delta_run_work(struct work_struct *work)
{
	struct delta_ctx *ctx = container_of(work, struct delta_ctx, run_work);
	struct delta_dev *delta = ctx->dev;
	const struct delta_dec *dec = ctx->dec;
	struct delta_au *au;
	struct delta_frame *frame = NULL;
	int ret = 0;
	bool discard = false;
	struct vb2_v4l2_buffer *vbuf;

	if (!dec) {
		dev_err(delta->dev, "%s no decoder opened yet\n", ctx->name);
		return;
	}

	/* protect instance against reentrancy */
	mutex_lock(&ctx->lock);

	vbuf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
	if (!vbuf) {
		dev_err(delta->dev, "%s no buffer to decode\n", ctx->name);
		mutex_unlock(&ctx->lock);
		return;
	}
	au = to_au(vbuf);
	au->size = vb2_get_plane_payload(&vbuf->vb2_buf, 0);
	au->dts = vbuf->vb2_buf.timestamp;

	/* dump access unit */
	dump_au(ctx, au);

	/* enable the hardware */
	if (!dec->pm) {
		ret = delta_get_sync(ctx);
		if (ret)
			goto err;
	}

	/* decode this access unit */
	ret = call_dec_op(dec, decode, ctx, au);

	/*
	 * if the (-ENODATA) value is returned, it refers to the interlaced
	 * stream case for which 2 access units are needed to get 1 frame.
	 * So, this returned value doesn't mean that the decoding fails, but
	 * indicates that the timestamp information of the access unit shall
	 * not be taken into account, and that the V4L2 buffer associated with
	 * the access unit shall be flagged with V4L2_BUF_FLAG_ERROR to inform
	 * the user of this situation
	 */
	if (ret == -ENODATA) {
		discard = true;
	} else if (ret) {
		dev_err(delta->dev, "%s decoding failed (%d)\n",
			ctx->name, ret);

		/* disable the hardware */
		if (!dec->pm)
			delta_put_autosuspend(ctx);

		goto err;
	}

	/* disable the hardware */
	if (!dec->pm)
		delta_put_autosuspend(ctx);

	/* push au timestamp in FIFO */
	if (!discard)
		delta_push_dts(ctx, au->dts);

	/* get available decoded frames */
	while (1) {
		ret = call_dec_op(dec, get_frame, ctx, &frame);
		if (ret == -ENODATA) {
			/* no more decoded frames */
			goto out;
		}
		if (ret) {
			dev_err(delta->dev, "%s  cannot get decoded frame (%d)\n",
				ctx->name, ret);
			goto out;
		}
		if (!frame) {
			dev_err(delta->dev,
				"%s  NULL decoded frame\n",
				ctx->name);
			ret = -EIO;
			goto out;
		}

		/* pop timestamp and mark frame with it */
		delta_pop_dts(ctx, &frame->dts);

		/* release decoded frame to user */
		delta_frame_done(ctx, frame, 0);
	}

out:
	requeue_free_frames(ctx);
	delta_au_done(ctx, au, (discard ? -ENODATA : 0));
	mutex_unlock(&ctx->lock);
	v4l2_m2m_job_finish(delta->m2m_dev, ctx->fh.m2m_ctx);
	return;

err:
	requeue_free_frames(ctx);
	delta_au_done(ctx, au, ret);
	mutex_unlock(&ctx->lock);
	v4l2_m2m_job_finish(delta->m2m_dev, ctx->fh.m2m_ctx);
}

static void delta_device_run(void *priv)
{
	struct delta_ctx *ctx = priv;
	struct delta_dev *delta = ctx->dev;

	queue_work(delta->work_queue, &ctx->run_work);
}

static void delta_job_abort(void *priv)
{
	struct delta_ctx *ctx = priv;
	struct delta_dev *delta = ctx->dev;

	dev_dbg(delta->dev, "%s aborting job\n", ctx->name);

	ctx->aborting = true;
}

static int delta_job_ready(void *priv)
{
	struct delta_ctx *ctx = priv;
	struct delta_dev *delta = ctx->dev;
	int src_bufs = v4l2_m2m_num_src_bufs_ready(ctx->fh.m2m_ctx);

	if (!src_bufs) {
		dev_dbg(delta->dev, "%s not ready: not enough video buffers.\n",
			ctx->name);
		return 0;
	}

	if (!v4l2_m2m_num_dst_bufs_ready(ctx->fh.m2m_ctx)) {
		dev_dbg(delta->dev, "%s not ready: not enough video capture buffers.\n",
			ctx->name);
		return 0;
	}

	if (ctx->aborting) {
		dev_dbg(delta->dev, "%s job not ready: aborting\n", ctx->name);
		return 0;
	}

	dev_dbg(delta->dev, "%s job ready\n", ctx->name);

	return 1;
}

/* mem-to-mem ops */
static const struct v4l2_m2m_ops delta_m2m_ops = {
	.device_run     = delta_device_run,
	.job_ready	= delta_job_ready,
	.job_abort      = delta_job_abort,
	.lock		= delta_lock,
	.unlock		= delta_unlock,
};

/*
 * VB2 queue operations
 */

static int delta_vb2_au_queue_setup(struct vb2_queue *vq,
				    unsigned int *num_buffers,
				    unsigned int *num_planes,
				    unsigned int sizes[],
				    struct device *alloc_devs[])
{
	struct delta_ctx *ctx = vb2_get_drv_priv(vq);
	unsigned int size = ctx->max_au_size;

	if (*num_planes)
		return sizes[0] < size ? -EINVAL : 0;

	*num_planes = 1;
	if (*num_buffers < 1)
		*num_buffers = 1;
	if (*num_buffers > DELTA_MAX_AUS)
		*num_buffers = DELTA_MAX_AUS;

	sizes[0] = size;

	return 0;
}

static int delta_vb2_au_prepare(struct vb2_buffer *vb)
{
	struct vb2_queue *q = vb->vb2_queue;
	struct delta_ctx *ctx = vb2_get_drv_priv(q);
	struct delta_dev *delta = ctx->dev;
	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
	struct delta_au *au = to_au(vbuf);

	if (!au->prepared) {
		/* get memory addresses */
		au->vaddr = vb2_plane_vaddr(&au->vbuf.vb2_buf, 0);
		au->paddr = vb2_dma_contig_plane_dma_addr
				(&au->vbuf.vb2_buf, 0);
		au->prepared = true;
		dev_dbg(delta->dev, "%s au[%d] prepared; virt=0x%p, phy=0x%pad\n",
			ctx->name, vb->index, au->vaddr, &au->paddr);
	}

	if (vbuf->field == V4L2_FIELD_ANY)
		vbuf->field = V4L2_FIELD_NONE;

	return 0;
}

static int delta_setup_frame(struct delta_ctx *ctx,
			     struct delta_frame *frame)
{
	struct delta_dev *delta = ctx->dev;
	const struct delta_dec *dec = ctx->dec;

	if (frame->index >= DELTA_MAX_FRAMES) {
		dev_err(delta->dev,
			"%s frame index=%d exceeds output frame count (%d)\n",
			ctx->name, frame->index, DELTA_MAX_FRAMES);
		return -EINVAL;
	}

	if (ctx->nb_of_frames >= DELTA_MAX_FRAMES) {
		dev_err(delta->dev,
			"%s number of frames exceeds output frame count (%d > %d)\n",
			ctx->name, ctx->nb_of_frames, DELTA_MAX_FRAMES);
		return -EINVAL;
	}

	if (frame->index != ctx->nb_of_frames) {
		dev_warn(delta->dev,
			 "%s frame index discontinuity detected, expected %d, got %d\n",
			 ctx->name, ctx->nb_of_frames, frame->index);
	}

	frame->state = DELTA_FRAME_FREE;
	ctx->frames[ctx->nb_of_frames] = frame;
	ctx->nb_of_frames++;

	/* setup frame on decoder side */
	return call_dec_op(dec, setup_frame, ctx, frame);
}

/*
 * default implementation of get_frameinfo decoder ops
 * matching frame information from stream information
 * & with default pixel format & default alignment.
 */
int delta_get_frameinfo_default(struct delta_ctx *ctx,
				struct delta_frameinfo *frameinfo)
{
	struct delta_streaminfo *streaminfo = &ctx->streaminfo;

	memset(frameinfo, 0, sizeof(*frameinfo));
	frameinfo->pixelformat = V4L2_PIX_FMT_NV12;
	frameinfo->width = streaminfo->width;
	frameinfo->height = streaminfo->height;
	frameinfo->aligned_width = ALIGN(streaminfo->width,
					 DELTA_WIDTH_ALIGNMENT);
	frameinfo->aligned_height = ALIGN(streaminfo->height,
					  DELTA_HEIGHT_ALIGNMENT);
	frameinfo->size = frame_size(frameinfo->aligned_width,
				     frameinfo->aligned_height,
				     frameinfo->pixelformat);
	if (streaminfo->flags & DELTA_STREAMINFO_FLAG_CROP) {
		frameinfo->flags |= DELTA_FRAMEINFO_FLAG_CROP;
		frameinfo->crop = streaminfo->crop;
	}
	if (streaminfo->flags & DELTA_STREAMINFO_FLAG_PIXELASPECT) {
		frameinfo->flags |= DELTA_FRAMEINFO_FLAG_PIXELASPECT;
		frameinfo->pixelaspect = streaminfo->pixelaspect;
	}
	frameinfo->field = streaminfo->field;

	return 0;
}

/*
 * default implementation of recycle decoder ops
 * consisting to relax the "decoded" frame state
 */
int delta_recycle_default(struct delta_ctx *pctx,
			  struct delta_frame *frame)
{
	frame->state &= ~DELTA_FRAME_DEC;

	return 0;
}

static void dump_frames_status(struct delta_ctx *ctx)
{
	struct delta_dev *delta = ctx->dev;
	unsigned int i;
	struct delta_frame *frame;
	unsigned char str[100] = "";

	dev_info(delta->dev,
		 "%s dumping frames status...\n", ctx->name);

	for (i = 0; i < ctx->nb_of_frames; i++) {
		frame = ctx->frames[i];
		dev_info(delta->dev,
			 "%s frame[%d] %s\n",
			 ctx->name, frame->index,
			 frame_state_str(frame->state,
					 str, sizeof(str)));
	}
}

int delta_get_free_frame(struct delta_ctx *ctx,
			 struct delta_frame **pframe)
{
	struct delta_dev *delta = ctx->dev;
	struct vb2_v4l2_buffer *vbuf;
	struct delta_frame *frame;

	*pframe = NULL;

	vbuf = v4l2_m2m_dst_buf_remove(ctx->fh.m2m_ctx);
	if (!vbuf) {
		dev_err(delta->dev, "%s no frame available",
			ctx->name);
		return -EIO;
	}

	frame = to_frame(vbuf);
	frame->state &= ~DELTA_FRAME_M2M;
	if (frame->state != DELTA_FRAME_FREE) {
		dev_err(delta->dev,
			"%s frame[%d] is not free\n",
			ctx->name, frame->index);
		dump_frames_status(ctx);
		return -ENODATA;
	}

	dev_dbg(delta->dev,
		"%s get free frame[%d]\n", ctx->name, frame->index);

	*pframe = frame;
	return 0;
}

int delta_get_sync(struct delta_ctx *ctx)
{
	struct delta_dev *delta = ctx->dev;
	int ret = 0;

	/* enable the hardware */
	ret = pm_runtime_get_sync(delta->dev);
	if (ret < 0) {
		dev_err(delta->dev, "%s pm_runtime_get_sync failed (%d)\n",
			__func__, ret);
		return ret;
	}

	return 0;
}

void delta_put_autosuspend(struct delta_ctx *ctx)
{
	struct delta_dev *delta = ctx->dev;

	pm_runtime_put_autosuspend(delta->dev);
}

static void delta_vb2_au_queue(struct vb2_buffer *vb)
{
	struct vb2_queue *q = vb->vb2_queue;
	struct delta_ctx *ctx = vb2_get_drv_priv(q);
	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);

	v4l2_m2m_buf_queue(ctx->fh.m2m_ctx, vbuf);
}

static int delta_vb2_au_start_streaming(struct vb2_queue *q,
					unsigned int count)
{
	struct delta_ctx *ctx = vb2_get_drv_priv(q);
	struct delta_dev *delta = ctx->dev;
	const struct delta_dec *dec = ctx->dec;
	struct delta_au *au;
	int ret = 0;
	struct vb2_v4l2_buffer *vbuf = NULL;
	struct delta_streaminfo *streaminfo = &ctx->streaminfo;
	struct delta_frameinfo *frameinfo = &ctx->frameinfo;
	unsigned char str1[100] = "";
	unsigned char str2[100] = "";

	if ((ctx->state != DELTA_STATE_WF_FORMAT) &&
	    (ctx->state != DELTA_STATE_WF_STREAMINFO))
		return 0;

	if (ctx->state == DELTA_STATE_WF_FORMAT) {
		/* open decoder if not yet done */
		ret = delta_open_decoder(ctx,
					 ctx->streaminfo.streamformat,
					 ctx->frameinfo.pixelformat, &dec);
		if (ret)
			goto err;
		ctx->dec = dec;
		ctx->state = DELTA_STATE_WF_STREAMINFO;
	}

	/*
	 * first buffer should contain stream header,
	 * decode it to get the infos related to stream
	 * such as width, height, dpb, ...
	 */
	vbuf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
	if (!vbuf) {
		dev_err(delta->dev, "%s failed to start streaming, no stream header buffer enqueued\n",
			ctx->name);
		ret = -EINVAL;
		goto err;
	}
	au = to_au(vbuf);
	au->size = vb2_get_plane_payload(&vbuf->vb2_buf, 0);
	au->dts = vbuf->vb2_buf.timestamp;

	delta_push_dts(ctx, au->dts);

	/* dump access unit */
	dump_au(ctx, au);

	/* decode this access unit */
	ret = call_dec_op(dec, decode, ctx, au);
	if (ret) {
		dev_err(delta->dev, "%s failed to start streaming, header decoding failed (%d)\n",
			ctx->name, ret);
		goto err;
	}

	ret = call_dec_op(dec, get_streaminfo, ctx, streaminfo);
	if (ret) {
		dev_dbg_ratelimited(delta->dev,
				    "%s failed to start streaming, valid stream header not yet decoded\n",
				    ctx->name);
		goto err;
	}
	ctx->flags |= DELTA_FLAG_STREAMINFO;

	ret = call_dec_op(dec, get_frameinfo, ctx, frameinfo);
	if (ret)
		goto err;
	ctx->flags |= DELTA_FLAG_FRAMEINFO;

	ctx->state = DELTA_STATE_READY;

	dev_dbg(delta->dev, "%s %s => %s\n", ctx->name,
		delta_streaminfo_str(streaminfo, str1, sizeof(str1)),
		delta_frameinfo_str(frameinfo, str2, sizeof(str2)));

	delta_au_done(ctx, au, ret);
	return 0;

err:
	/*
	 * return all buffers to vb2 in QUEUED state.
	 * This will give ownership back to userspace
	 */
	if (vbuf)
		v4l2_m2m_buf_done(vbuf, VB2_BUF_STATE_QUEUED);

	while ((vbuf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx)))
		v4l2_m2m_buf_done(vbuf, VB2_BUF_STATE_QUEUED);
	return ret;
}

static void delta_vb2_au_stop_streaming(struct vb2_queue *q)
{
	struct delta_ctx *ctx = vb2_get_drv_priv(q);
	struct vb2_v4l2_buffer *vbuf;

	delta_flush_dts(ctx);

	/* return all buffers to vb2 in ERROR state */
	while ((vbuf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx)))
		v4l2_m2m_buf_done(vbuf, VB2_BUF_STATE_ERROR);

	ctx->au_num = 0;

	ctx->aborting = false;
}

static int delta_vb2_frame_queue_setup(struct vb2_queue *vq,
				       unsigned int *num_buffers,
				       unsigned int *num_planes,
				       unsigned int sizes[],
				       struct device *alloc_devs[])
{
	struct delta_ctx *ctx = vb2_get_drv_priv(vq);
	struct delta_dev *delta = ctx->dev;
	struct delta_streaminfo *streaminfo = &ctx->streaminfo;
	struct delta_frameinfo *frameinfo = &ctx->frameinfo;
	unsigned int size = frameinfo->size;

	/*
	 * the number of output buffers needed for decoding =
	 * user need (*num_buffers given, usually for display pipeline) +
	 * stream need (streaminfo->dpb) +
	 * decoding peak smoothing (depends on DELTA IP perf)
	 */
	if (*num_buffers < DELTA_MIN_FRAME_USER) {
		dev_dbg(delta->dev,
			"%s num_buffers too low (%d), increasing to %d\n",
			ctx->name, *num_buffers, DELTA_MIN_FRAME_USER);
		*num_buffers = DELTA_MIN_FRAME_USER;
	}

	*num_buffers += streaminfo->dpb + DELTA_PEAK_FRAME_SMOOTHING;

	if (*num_buffers > DELTA_MAX_FRAMES) {
		dev_dbg(delta->dev,
			"%s output frame count too high (%d), cut to %d\n",
			ctx->name, *num_buffers, DELTA_MAX_FRAMES);
		*num_buffers = DELTA_MAX_FRAMES;
	}

	if (*num_planes)
		return sizes[0] < size ? -EINVAL : 0;

	/* single plane for Y and CbCr */
	*num_planes = 1;

	sizes[0] = size;

	ctx->nb_of_frames = 0;

	return 0;
}

static int delta_vb2_frame_prepare(struct vb2_buffer *vb)
{
	struct vb2_queue *q = vb->vb2_queue;
	struct delta_ctx *ctx = vb2_get_drv_priv(q);
	struct delta_dev *delta = ctx->dev;
	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
	struct delta_frame *frame = to_frame(vbuf);
	int ret = 0;

	if (!frame->prepared) {
		frame->index = vbuf->vb2_buf.index;
		frame->vaddr = vb2_plane_vaddr(&vbuf->vb2_buf, 0);
		frame->paddr = vb2_dma_contig_plane_dma_addr(&vbuf->vb2_buf, 0);
		frame->info = ctx->frameinfo;

		ret = delta_setup_frame(ctx, frame);
		if (ret) {
			dev_err(delta->dev,
				"%s setup_frame() failed (%d)\n",
				ctx->name, ret);
			return ret;
		}
		frame->prepared = true;
		dev_dbg(delta->dev,
			"%s frame[%d] prepared; virt=0x%p, phy=0x%pad\n",
			ctx->name, vb->index, frame->vaddr,
			&frame->paddr);
	}

	frame->flags = vbuf->flags;

	return 0;
}

static void delta_vb2_frame_finish(struct vb2_buffer *vb)
{
	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
	struct delta_frame *frame = to_frame(vbuf);

	/* update V4L2 fields for user */
	vb2_set_plane_payload(&vbuf->vb2_buf, 0, frame->info.size);
	vb->timestamp = frame->dts;
	vbuf->field = frame->field;
	vbuf->flags = frame->flags;
}

static void delta_vb2_frame_queue(struct vb2_buffer *vb)
{
	struct vb2_queue *q = vb->vb2_queue;
	struct delta_ctx *ctx = vb2_get_drv_priv(q);
	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
	struct delta_frame *frame = to_frame(vbuf);

	if (ctx->state == DELTA_STATE_WF_EOS) {
		/* new frame available, EOS can now be completed */
		delta_complete_eos(ctx, frame);

		ctx->state = DELTA_STATE_EOS;

		/* return, no need to recycle this buffer to decoder */
		return;
	}

	/* recycle this frame */
	delta_recycle(ctx, frame);
}

static void delta_vb2_frame_stop_streaming(struct vb2_queue *q)
{
	struct delta_ctx *ctx = vb2_get_drv_priv(q);
	struct vb2_v4l2_buffer *vbuf;
	struct delta_frame *frame;
	const struct delta_dec *dec = ctx->dec;
	unsigned int i;

	delta_flush_dts(ctx);

	call_dec_op(dec, flush, ctx);

	/*
	 * return all buffers to vb2 in ERROR state
	 * & reset each frame state to OUT
	 */
	for (i = 0; i < ctx->nb_of_frames; i++) {
		frame = ctx->frames[i];
		if (!(frame->state & DELTA_FRAME_OUT)) {
			vbuf = &frame->vbuf;
			v4l2_m2m_buf_done(vbuf, VB2_BUF_STATE_ERROR);
		}
		frame->state = DELTA_FRAME_OUT;
	}

	ctx->frame_num = 0;

	ctx->aborting = false;
}

/* VB2 queue ops */
static const struct vb2_ops delta_vb2_au_ops = {
	.queue_setup = delta_vb2_au_queue_setup,
	.buf_prepare = delta_vb2_au_prepare,
	.buf_queue = delta_vb2_au_queue,
	.wait_prepare = vb2_ops_wait_prepare,
	.wait_finish = vb2_ops_wait_finish,
	.start_streaming = delta_vb2_au_start_streaming,
	.stop_streaming = delta_vb2_au_stop_streaming,
};

static const struct vb2_ops delta_vb2_frame_ops = {
	.queue_setup = delta_vb2_frame_queue_setup,
	.buf_prepare = delta_vb2_frame_prepare,
	.buf_finish = delta_vb2_frame_finish,
	.buf_queue = delta_vb2_frame_queue,
	.wait_prepare = vb2_ops_wait_prepare,
	.wait_finish = vb2_ops_wait_finish,
	.stop_streaming = delta_vb2_frame_stop_streaming,
};

/*
 * V4L2 file operations
 */

static int queue_init(void *priv,
		      struct vb2_queue *src_vq, struct vb2_queue *dst_vq)
{
	struct vb2_queue *q;
	struct delta_ctx *ctx = priv;
	struct delta_dev *delta = ctx->dev;
	int ret;

	/* setup vb2 queue for stream input */
	q = src_vq;
	q->type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
	q->io_modes = VB2_MMAP | VB2_DMABUF;
	q->drv_priv = ctx;
	/* overload vb2 buf with private au struct */
	q->buf_struct_size = sizeof(struct delta_au);
	q->ops = &delta_vb2_au_ops;
	q->mem_ops = &vb2_dma_contig_memops;
	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
	q->lock = &delta->lock;
	q->dev = delta->dev;

	ret = vb2_queue_init(q);
	if (ret)
		return ret;

	/* setup vb2 queue for frame output */
	q = dst_vq;
	q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
	q->io_modes = VB2_MMAP | VB2_DMABUF;
	q->drv_priv = ctx;
	/* overload vb2 buf with private frame struct */
	q->buf_struct_size = sizeof(struct delta_frame)
			     + DELTA_MAX_FRAME_PRIV_SIZE;
	q->ops = &delta_vb2_frame_ops;
	q->mem_ops = &vb2_dma_contig_memops;
	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
	q->lock = &delta->lock;
	q->dev = delta->dev;

	return vb2_queue_init(q);
}

static int delta_open(struct file *file)
{
	struct delta_dev *delta = video_drvdata(file);
	struct delta_ctx *ctx = NULL;
	int ret = 0;

	mutex_lock(&delta->lock);

	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
	if (!ctx) {
		ret = -ENOMEM;
		goto err;
	}
	ctx->dev = delta;

	v4l2_fh_init(&ctx->fh, video_devdata(file));
	file->private_data = &ctx->fh;
	v4l2_fh_add(&ctx->fh);

	INIT_WORK(&ctx->run_work, delta_run_work);
	mutex_init(&ctx->lock);

	ctx->fh.m2m_ctx = v4l2_m2m_ctx_init(delta->m2m_dev, ctx,
					    queue_init);
	if (IS_ERR(ctx->fh.m2m_ctx)) {
		ret = PTR_ERR(ctx->fh.m2m_ctx);
		dev_err(delta->dev, "%s failed to initialize m2m context (%d)\n",
			DELTA_PREFIX, ret);
		goto err_fh_del;
	}

	/*
	 * wait stream format to determine which
	 * decoder to open
	 */
	ctx->state = DELTA_STATE_WF_FORMAT;

	INIT_LIST_HEAD(&ctx->dts);

	/* set the instance name */
	delta->instance_id++;
	snprintf(ctx->name, sizeof(ctx->name), "[%3d:----]",
		 delta->instance_id);

	/* default parameters for frame and stream */
	set_default_params(ctx);

	/* enable ST231 clocks */
	if (delta->clk_st231)
		if (clk_prepare_enable(delta->clk_st231))
			dev_warn(delta->dev, "failed to enable st231 clk\n");

	/* enable FLASH_PROMIP clock */
	if (delta->clk_flash_promip)
		if (clk_prepare_enable(delta->clk_flash_promip))
			dev_warn(delta->dev, "failed to enable delta promip clk\n");

	mutex_unlock(&delta->lock);

	dev_dbg(delta->dev, "%s decoder instance created\n", ctx->name);

	return 0;

err_fh_del:
	v4l2_fh_del(&ctx->fh);
	v4l2_fh_exit(&ctx->fh);
	kfree(ctx);
err:
	mutex_unlock(&delta->lock);

	return ret;
}

static int delta_release(struct file *file)
{
	struct delta_ctx *ctx = to_ctx(file->private_data);
	struct delta_dev *delta = ctx->dev;
	const struct delta_dec *dec = ctx->dec;

	mutex_lock(&delta->lock);

	/* close decoder */
	call_dec_op(dec, close, ctx);

	/*
	 * trace a summary of instance
	 * before closing (debug purpose)
	 */
	delta_trace_summary(ctx);

	v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);

	v4l2_fh_del(&ctx->fh);
	v4l2_fh_exit(&ctx->fh);

	/* disable ST231 clocks */
	if (delta->clk_st231)
		clk_disable_unprepare(delta->clk_st231);

	/* disable FLASH_PROMIP clock */
	if (delta->clk_flash_promip)
		clk_disable_unprepare(delta->clk_flash_promip);

	dev_dbg(delta->dev, "%s decoder instance released\n", ctx->name);

	kfree(ctx);

	mutex_unlock(&delta->lock);
	return 0;
}

/* V4L2 file ops */
static const struct v4l2_file_operations delta_fops = {
	.owner = THIS_MODULE,
	.open = delta_open,
	.release = delta_release,
	.unlocked_ioctl = video_ioctl2,
	.mmap = v4l2_m2m_fop_mmap,
	.poll = v4l2_m2m_fop_poll,
};

/*
 * Platform device operations
 */

static int delta_register_device(struct delta_dev *delta)
{
	int ret;
	struct video_device *vdev;

	if (!delta)
		return -ENODEV;

	delta->m2m_dev = v4l2_m2m_init(&delta_m2m_ops);
	if (IS_ERR(delta->m2m_dev)) {
		dev_err(delta->dev, "%s failed to initialize v4l2-m2m device\n",
			DELTA_PREFIX);
		ret = PTR_ERR(delta->m2m_dev);
		goto err;
	}

	vdev = video_device_alloc();
	if (!vdev) {
		dev_err(delta->dev, "%s failed to allocate video device\n",
			DELTA_PREFIX);
		ret = -ENOMEM;
		goto err_m2m_release;
	}

	vdev->fops = &delta_fops;
	vdev->ioctl_ops = &delta_ioctl_ops;
	vdev->release = video_device_release;
	vdev->lock = &delta->lock;
	vdev->vfl_dir = VFL_DIR_M2M;
	vdev->device_caps = V4L2_CAP_STREAMING | V4L2_CAP_VIDEO_M2M;
	vdev->v4l2_dev = &delta->v4l2_dev;
	snprintf(vdev->name, sizeof(vdev->name), "%s-%s",
		 DELTA_NAME, DELTA_FW_VERSION);

	ret = video_register_device(vdev, VFL_TYPE_GRABBER, -1);
	if (ret) {
		dev_err(delta->dev, "%s failed to register video device\n",
			DELTA_PREFIX);
		goto err_vdev_release;
	}

	delta->vdev = vdev;
	video_set_drvdata(vdev, delta);
	return 0;

err_vdev_release:
	video_device_release(vdev);
err_m2m_release:
	v4l2_m2m_release(delta->m2m_dev);
err:
	return ret;
}

static void delta_unregister_device(struct delta_dev *delta)
{
	if (!delta)
		return;

	if (delta->m2m_dev)
		v4l2_m2m_release(delta->m2m_dev);

	video_unregister_device(delta->vdev);
}

static int delta_probe(struct platform_device *pdev)
{
	struct delta_dev *delta;
	struct device *dev = &pdev->dev;
	int ret;

	delta = devm_kzalloc(dev, sizeof(*delta), GFP_KERNEL);
	if (!delta) {
		ret = -ENOMEM;
		goto err;
	}

	delta->dev = dev;
	delta->pdev = pdev;
	platform_set_drvdata(pdev, delta);

	mutex_init(&delta->lock);

	/* get clock resources */
	delta->clk_delta = devm_clk_get(dev, "delta");
	if (IS_ERR(delta->clk_delta)) {
		dev_dbg(dev, "%s can't get delta clock\n", DELTA_PREFIX);
		delta->clk_delta = NULL;
	}

	delta->clk_st231 = devm_clk_get(dev, "delta-st231");
	if (IS_ERR(delta->clk_st231)) {
		dev_dbg(dev, "%s can't get delta-st231 clock\n", DELTA_PREFIX);
		delta->clk_st231 = NULL;
	}

	delta->clk_flash_promip = devm_clk_get(dev, "delta-flash-promip");
	if (IS_ERR(delta->clk_flash_promip)) {
		dev_dbg(dev, "%s can't get delta-flash-promip clock\n",
			DELTA_PREFIX);
		delta->clk_flash_promip = NULL;
	}

	/* init pm_runtime used for power management */
	pm_runtime_set_autosuspend_delay(dev, DELTA_HW_AUTOSUSPEND_DELAY_MS);
	pm_runtime_use_autosuspend(dev);
	pm_runtime_set_suspended(dev);
	pm_runtime_enable(dev);

	/* init firmware ipc channel */
	ret = delta_ipc_init(delta);
	if (ret) {
		dev_err(delta->dev, "%s failed to initialize firmware ipc channel\n",
			DELTA_PREFIX);
		goto err;
	}

	/* register all available decoders */
	register_decoders(delta);

	/* register all supported formats */
	register_formats(delta);

	/* register on V4L2 */
	ret = v4l2_device_register(dev, &delta->v4l2_dev);
	if (ret) {
		dev_err(delta->dev, "%s failed to register V4L2 device\n",
			DELTA_PREFIX);
		goto err;
	}

	delta->work_queue = create_workqueue(DELTA_NAME);
	if (!delta->work_queue) {
		dev_err(delta->dev, "%s failed to allocate work queue\n",
			DELTA_PREFIX);
		ret = -ENOMEM;
		goto err_v4l2;
	}

	/* register device */
	ret = delta_register_device(delta);
	if (ret)
		goto err_work_queue;

	dev_info(dev, "%s %s registered as /dev/video%d\n",
		 DELTA_PREFIX, delta->vdev->name, delta->vdev->num);

	return 0;

err_work_queue:
	destroy_workqueue(delta->work_queue);
err_v4l2:
	v4l2_device_unregister(&delta->v4l2_dev);
err:
	return ret;
}

static int delta_remove(struct platform_device *pdev)
{
	struct delta_dev *delta = platform_get_drvdata(pdev);

	delta_ipc_exit(delta);

	delta_unregister_device(delta);

	destroy_workqueue(delta->work_queue);

	pm_runtime_put_autosuspend(delta->dev);
	pm_runtime_disable(delta->dev);

	v4l2_device_unregister(&delta->v4l2_dev);

	return 0;
}

static int delta_runtime_suspend(struct device *dev)
{
	struct delta_dev *delta = dev_get_drvdata(dev);

	if (delta->clk_delta)
		clk_disable_unprepare(delta->clk_delta);

	return 0;
}

static int delta_runtime_resume(struct device *dev)
{
	struct delta_dev *delta = dev_get_drvdata(dev);

	if (delta->clk_delta)
		if (clk_prepare_enable(delta->clk_delta))
			dev_warn(dev, "failed to prepare/enable delta clk\n");

	return 0;
}

/* PM ops */
static const struct dev_pm_ops delta_pm_ops = {
	.runtime_suspend = delta_runtime_suspend,
	.runtime_resume = delta_runtime_resume,
};

static const struct of_device_id delta_match_types[] = {
	{
	 .compatible = "st,st-delta",
	},
	{
	 /* end node */
	}
};

MODULE_DEVICE_TABLE(of, delta_match_types);

static struct platform_driver delta_driver = {
	.probe = delta_probe,
	.remove = delta_remove,
	.driver = {
		   .name = DELTA_NAME,
		   .of_match_table = delta_match_types,
		   .pm = &delta_pm_ops},
};

module_platform_driver(delta_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Hugues Fruchet <hugues.fruchet@st.com>");
MODULE_DESCRIPTION("STMicroelectronics DELTA video decoder V4L2 driver");