// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) STMicroelectronics SA 2015
 * Authors: Hugues Fruchet <hugues.fruchet@st.com>
 *          Jean-Christophe Trotin <jean-christophe.trotin@st.com>
 *          for STMicroelectronics.
 */

#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 "[---:----]"

static inline struct delta_ctx *file_to_ctx(struct file *filp)
{
        return container_of(file_to_v4l2_fh(filp), 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_obj(*dts);
        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 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 = file_to_ctx(file);
        struct delta_dev *delta = ctx->dev;

        strscpy(cap->driver, DELTA_NAME, sizeof(cap->driver));
        strscpy(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 = file_to_ctx(file);
        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 = file_to_ctx(file);
        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 = file_to_ctx(file);
        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 = file_to_ctx(file);
        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 = file_to_ctx(file);
        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 = file_to_ctx(file);
        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 = file_to_ctx(file);
        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 = file_to_ctx(file);
        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 = file_to_ctx(file);
        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)
{
        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 = file_to_ctx(file);
        int ret = 0;

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

        return delta_decoder_stop_cmd(ctx);
}

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);
                        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,
};

/*
 * 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_resume_and_get(delta->dev);
        if (ret < 0) {
                dev_err(delta->dev, "%s pm_runtime_resume_and_get 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,
        .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,
        .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_obj(*ctx);
        if (!ctx) {
                ret = -ENOMEM;
                goto err;
        }
        ctx->dev = delta;

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

        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 (clk_prepare_enable(delta->clk_st231))
                dev_warn(delta->dev, "failed to enable st231 clk\n");

        /* enable FLASH_PROMIP clock */
        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, file);
        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 = file_to_ctx(file);
        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, file);
        v4l2_fh_exit(&ctx->fh);

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

        /* disable FLASH_PROMIP clock */
        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_VIDEO, -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_pm_disable;
        }

        /* 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_pm_disable;
        }

        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_pm_disable:
        pm_runtime_disable(dev);
err:
        return ret;
}

static void 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);
}

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

        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 (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");