root/drivers/media/platform/ti/cal/cal-video.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * TI Camera Access Layer (CAL) - Video Device
 *
 * Copyright (c) 2015-2020 Texas Instruments Inc.
 *
 * Authors:
 *      Benoit Parrot <bparrot@ti.com>
 *      Laurent Pinchart <laurent.pinchart@ideasonboard.com>
 */

#include <linux/ioctl.h>
#include <linux/pm_runtime.h>
#include <linux/videodev2.h>

#include <media/media-device.h>
#include <media/v4l2-common.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-device.h>
#include <media/v4l2-event.h>
#include <media/v4l2-fh.h>
#include <media/v4l2-ioctl.h>
#include <media/videobuf2-core.h>
#include <media/videobuf2-dma-contig.h>

#include "cal.h"

/* ------------------------------------------------------------------
 *      V4L2 Common IOCTLs
 * ------------------------------------------------------------------
 */

static int cal_querycap(struct file *file, void *priv,
                        struct v4l2_capability *cap)
{
        strscpy(cap->driver, CAL_MODULE_NAME, sizeof(cap->driver));
        strscpy(cap->card, CAL_MODULE_NAME, sizeof(cap->card));

        return 0;
}

static int cal_g_fmt_vid_cap(struct file *file, void *priv,
                             struct v4l2_format *f)
{
        struct cal_ctx *ctx = video_drvdata(file);

        *f = ctx->v_fmt;

        return 0;
}

/* ------------------------------------------------------------------
 *      V4L2 Video Node Centric IOCTLs
 * ------------------------------------------------------------------
 */

static const struct cal_format_info *find_format_by_pix(struct cal_ctx *ctx,
                                                        u32 pixelformat)
{
        const struct cal_format_info *fmtinfo;
        unsigned int k;

        for (k = 0; k < ctx->num_active_fmt; k++) {
                fmtinfo = ctx->active_fmt[k];
                if (fmtinfo->fourcc == pixelformat)
                        return fmtinfo;
        }

        return NULL;
}

static const struct cal_format_info *find_format_by_code(struct cal_ctx *ctx,
                                                         u32 code)
{
        const struct cal_format_info *fmtinfo;
        unsigned int k;

        for (k = 0; k < ctx->num_active_fmt; k++) {
                fmtinfo = ctx->active_fmt[k];
                if (fmtinfo->code == code)
                        return fmtinfo;
        }

        return NULL;
}

static int cal_legacy_enum_fmt_vid_cap(struct file *file, void *priv,
                                       struct v4l2_fmtdesc *f)
{
        struct cal_ctx *ctx = video_drvdata(file);
        const struct cal_format_info *fmtinfo;

        if (f->index >= ctx->num_active_fmt)
                return -EINVAL;

        fmtinfo = ctx->active_fmt[f->index];

        f->pixelformat = fmtinfo->fourcc;
        f->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
        return 0;
}

static int __subdev_get_format(struct cal_ctx *ctx,
                               struct v4l2_mbus_framefmt *fmt)
{
        struct v4l2_subdev_format sd_fmt = {
                .which = V4L2_SUBDEV_FORMAT_ACTIVE,
                .pad = 0,
        };
        struct v4l2_mbus_framefmt *mbus_fmt = &sd_fmt.format;
        struct v4l2_subdev *sd = ctx->phy->source;
        int ret;

        ret = v4l2_subdev_call_state_active(sd, pad, get_fmt, &sd_fmt);
        if (ret)
                return ret;

        *fmt = *mbus_fmt;

        ctx_dbg(1, ctx, "%s %dx%d code:%04X\n", __func__,
                fmt->width, fmt->height, fmt->code);

        return 0;
}

static int __subdev_set_format(struct cal_ctx *ctx,
                               struct v4l2_mbus_framefmt *fmt)
{
        struct v4l2_subdev_format sd_fmt = {
                .which = V4L2_SUBDEV_FORMAT_ACTIVE,
                .pad = 0,
        };
        struct v4l2_mbus_framefmt *mbus_fmt = &sd_fmt.format;
        struct v4l2_subdev *sd = ctx->phy->source;
        int ret;

        *mbus_fmt = *fmt;

        ret = v4l2_subdev_call_state_active(sd, pad, set_fmt, &sd_fmt);
        if (ret)
                return ret;

        ctx_dbg(1, ctx, "%s %dx%d code:%04X\n", __func__,
                fmt->width, fmt->height, fmt->code);

        return 0;
}

static void cal_calc_format_size(struct cal_ctx *ctx,
                                 const struct cal_format_info *fmtinfo,
                                 struct v4l2_format *f)
{
        u32 bpl, max_width;

        /*
         * Maximum width is bound by the DMA max width in bytes.
         * We need to recalculate the actual maxi width depending on the
         * number of bytes per pixels required.
         */
        max_width = CAL_MAX_WIDTH_BYTES / (ALIGN(fmtinfo->bpp, 8) >> 3);
        v4l_bound_align_image(&f->fmt.pix.width, 48, max_width, 2,
                              &f->fmt.pix.height, 32, CAL_MAX_HEIGHT_LINES,
                              0, 0);

        bpl = (f->fmt.pix.width * ALIGN(fmtinfo->bpp, 8)) >> 3;
        f->fmt.pix.bytesperline = ALIGN(bpl, 16);

        f->fmt.pix.sizeimage = f->fmt.pix.height *
                               f->fmt.pix.bytesperline;

        ctx_dbg(3, ctx, "%s: fourcc: %p4cc size: %dx%d bpl:%d img_size:%d\n",
                __func__, &f->fmt.pix.pixelformat,
                f->fmt.pix.width, f->fmt.pix.height,
                f->fmt.pix.bytesperline, f->fmt.pix.sizeimage);
}

static int cal_legacy_try_fmt_vid_cap(struct file *file, void *priv,
                                      struct v4l2_format *f)
{
        struct cal_ctx *ctx = video_drvdata(file);
        struct v4l2_subdev *sd = ctx->phy->source;
        const struct cal_format_info *fmtinfo;
        struct v4l2_subdev_frame_size_enum fse = {
                .which = V4L2_SUBDEV_FORMAT_ACTIVE,
        };
        int found;

        fmtinfo = find_format_by_pix(ctx, f->fmt.pix.pixelformat);
        if (!fmtinfo) {
                ctx_dbg(3, ctx, "Fourcc format (0x%08x) not found.\n",
                        f->fmt.pix.pixelformat);

                /* Just get the first one enumerated */
                fmtinfo = ctx->active_fmt[0];
                f->fmt.pix.pixelformat = fmtinfo->fourcc;
        }

        f->fmt.pix.field = ctx->v_fmt.fmt.pix.field;

        /* check for/find a valid width/height */
        found = false;
        fse.pad = 0;
        fse.code = fmtinfo->code;
        for (fse.index = 0; ; fse.index++) {
                int ret;

                ret = v4l2_subdev_call_state_active(sd, pad, enum_frame_size,
                                                    &fse);
                if (ret)
                        break;

                if ((f->fmt.pix.width == fse.max_width) &&
                    (f->fmt.pix.height == fse.max_height)) {
                        found = true;
                        break;
                } else if ((f->fmt.pix.width >= fse.min_width) &&
                         (f->fmt.pix.width <= fse.max_width) &&
                         (f->fmt.pix.height >= fse.min_height) &&
                         (f->fmt.pix.height <= fse.max_height)) {
                        found = true;
                        break;
                }
        }

        if (!found) {
                /* use existing values as default */
                f->fmt.pix.width = ctx->v_fmt.fmt.pix.width;
                f->fmt.pix.height =  ctx->v_fmt.fmt.pix.height;
        }

        /*
         * Use current colorspace for now, it will get
         * updated properly during s_fmt
         */
        f->fmt.pix.colorspace = ctx->v_fmt.fmt.pix.colorspace;
        cal_calc_format_size(ctx, fmtinfo, f);
        return 0;
}

static int cal_legacy_s_fmt_vid_cap(struct file *file, void *priv,
                                    struct v4l2_format *f)
{
        struct cal_ctx *ctx = video_drvdata(file);
        struct v4l2_subdev *sd = &ctx->phy->subdev;
        struct vb2_queue *q = &ctx->vb_vidq;
        struct v4l2_subdev_format sd_fmt = {
                .which = V4L2_SUBDEV_FORMAT_ACTIVE,
                .pad = CAL_CAMERARX_PAD_SINK,
        };
        const struct cal_format_info *fmtinfo;
        int ret;

        if (vb2_is_busy(q)) {
                ctx_dbg(3, ctx, "%s device busy\n", __func__);
                return -EBUSY;
        }

        ret = cal_legacy_try_fmt_vid_cap(file, priv, f);
        if (ret < 0)
                return ret;

        fmtinfo = find_format_by_pix(ctx, f->fmt.pix.pixelformat);

        v4l2_fill_mbus_format(&sd_fmt.format, &f->fmt.pix, fmtinfo->code);

        ret = __subdev_set_format(ctx, &sd_fmt.format);
        if (ret)
                return ret;

        /* Just double check nothing has gone wrong */
        if (sd_fmt.format.code != fmtinfo->code) {
                ctx_dbg(3, ctx,
                        "%s subdev changed format on us, this should not happen\n",
                        __func__);
                return -EINVAL;
        }

        v4l2_fill_pix_format(&ctx->v_fmt.fmt.pix, &sd_fmt.format);
        ctx->v_fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
        ctx->v_fmt.fmt.pix.pixelformat = fmtinfo->fourcc;
        ctx->v_fmt.fmt.pix.field = sd_fmt.format.field;
        cal_calc_format_size(ctx, fmtinfo, &ctx->v_fmt);

        v4l2_subdev_call_state_active(sd, pad, set_fmt, &sd_fmt);

        ctx->fmtinfo = fmtinfo;
        *f = ctx->v_fmt;

        return 0;
}

static int cal_legacy_enum_framesizes(struct file *file, void *fh,
                                      struct v4l2_frmsizeenum *fsize)
{
        struct cal_ctx *ctx = video_drvdata(file);
        struct v4l2_subdev *sd = ctx->phy->source;
        const struct cal_format_info *fmtinfo;
        struct v4l2_subdev_frame_size_enum fse = {
                .index = fsize->index,
                .pad = 0,
                .which = V4L2_SUBDEV_FORMAT_ACTIVE,
        };
        int ret;

        /* check for valid format */
        fmtinfo = find_format_by_pix(ctx, fsize->pixel_format);
        if (!fmtinfo) {
                ctx_dbg(3, ctx, "Invalid pixel code: %x\n",
                        fsize->pixel_format);
                return -EINVAL;
        }

        fse.code = fmtinfo->code;

        ret = v4l2_subdev_call_state_active(sd, pad, enum_frame_size, &fse);
        if (ret)
                return ret;

        ctx_dbg(1, ctx, "%s: index: %d code: %x W:[%d,%d] H:[%d,%d]\n",
                __func__, fse.index, fse.code, fse.min_width, fse.max_width,
                fse.min_height, fse.max_height);

        fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
        fsize->discrete.width = fse.max_width;
        fsize->discrete.height = fse.max_height;

        return 0;
}

static int cal_legacy_enum_input(struct file *file, void *priv,
                                 struct v4l2_input *inp)
{
        if (inp->index > 0)
                return -EINVAL;

        inp->type = V4L2_INPUT_TYPE_CAMERA;
        sprintf(inp->name, "Camera %u", inp->index);
        return 0;
}

static int cal_legacy_g_input(struct file *file, void *priv, unsigned int *i)
{
        *i = 0;
        return 0;
}

static int cal_legacy_s_input(struct file *file, void *priv, unsigned int i)
{
        return i > 0 ? -EINVAL : 0;
}

/* timeperframe is arbitrary and continuous */
static int cal_legacy_enum_frameintervals(struct file *file, void *priv,
                                          struct v4l2_frmivalenum *fival)
{
        struct cal_ctx *ctx = video_drvdata(file);
        struct v4l2_subdev *sd = ctx->phy->source;
        const struct cal_format_info *fmtinfo;
        struct v4l2_subdev_frame_interval_enum fie = {
                .index = fival->index,
                .width = fival->width,
                .height = fival->height,
                .which = V4L2_SUBDEV_FORMAT_ACTIVE,
        };
        int ret;

        fmtinfo = find_format_by_pix(ctx, fival->pixel_format);
        if (!fmtinfo)
                return -EINVAL;

        fie.code = fmtinfo->code;

        ret = v4l2_subdev_call_state_active(sd, pad, enum_frame_interval, &fie);
        if (ret)
                return ret;
        fival->type = V4L2_FRMIVAL_TYPE_DISCRETE;
        fival->discrete = fie.interval;

        return 0;
}

static int cal_legacy_g_parm(struct file *file, void *fh, struct v4l2_streamparm *a)
{
        struct cal_ctx *ctx = video_drvdata(file);

        return v4l2_g_parm_cap(video_devdata(file), ctx->phy->source, a);
}

static int cal_legacy_s_parm(struct file *file, void *fh, struct v4l2_streamparm *a)
{
        struct cal_ctx *ctx = video_drvdata(file);

        return v4l2_s_parm_cap(video_devdata(file), ctx->phy->source, a);
}

static const struct v4l2_ioctl_ops cal_ioctl_legacy_ops = {
        .vidioc_querycap      = cal_querycap,
        .vidioc_enum_fmt_vid_cap  = cal_legacy_enum_fmt_vid_cap,
        .vidioc_g_fmt_vid_cap     = cal_g_fmt_vid_cap,
        .vidioc_try_fmt_vid_cap   = cal_legacy_try_fmt_vid_cap,
        .vidioc_s_fmt_vid_cap     = cal_legacy_s_fmt_vid_cap,
        .vidioc_enum_framesizes   = cal_legacy_enum_framesizes,
        .vidioc_reqbufs       = vb2_ioctl_reqbufs,
        .vidioc_create_bufs   = vb2_ioctl_create_bufs,
        .vidioc_prepare_buf   = vb2_ioctl_prepare_buf,
        .vidioc_querybuf      = vb2_ioctl_querybuf,
        .vidioc_qbuf          = vb2_ioctl_qbuf,
        .vidioc_dqbuf         = vb2_ioctl_dqbuf,
        .vidioc_expbuf        = vb2_ioctl_expbuf,
        .vidioc_enum_input    = cal_legacy_enum_input,
        .vidioc_g_input       = cal_legacy_g_input,
        .vidioc_s_input       = cal_legacy_s_input,
        .vidioc_enum_frameintervals = cal_legacy_enum_frameintervals,
        .vidioc_streamon      = vb2_ioctl_streamon,
        .vidioc_streamoff     = vb2_ioctl_streamoff,
        .vidioc_log_status    = v4l2_ctrl_log_status,
        .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
        .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
        .vidioc_g_parm          = cal_legacy_g_parm,
        .vidioc_s_parm          = cal_legacy_s_parm,
};

/* ------------------------------------------------------------------
 *      V4L2 Media Controller Centric IOCTLs
 * ------------------------------------------------------------------
 */

static int cal_mc_enum_fmt_vid_cap(struct file *file, void  *priv,
                                   struct v4l2_fmtdesc *f)
{
        unsigned int i;
        unsigned int idx;

        if (f->index >= cal_num_formats)
                return -EINVAL;

        idx = 0;

        for (i = 0; i < cal_num_formats; ++i) {
                if (cal_formats[i].meta)
                        continue;

                if (f->mbus_code && cal_formats[i].code != f->mbus_code)
                        continue;

                if (idx == f->index) {
                        f->pixelformat = cal_formats[i].fourcc;
                        f->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
                        return 0;
                }

                idx++;
        }

        return -EINVAL;
}

static void cal_mc_try_fmt(struct cal_ctx *ctx, struct v4l2_format *f,
                           const struct cal_format_info **info)
{
        struct v4l2_pix_format *format = &f->fmt.pix;
        const struct cal_format_info *fmtinfo;
        unsigned int bpp;

        /*
         * Default to the first format if the requested pixel format code isn't
         * supported.
         */
        fmtinfo = cal_format_by_fourcc(f->fmt.pix.pixelformat);
        if (!fmtinfo || fmtinfo->meta)
                fmtinfo = &cal_formats[0];

        /*
         * Clamp the size, update the pixel format. The field and colorspace are
         * accepted as-is, except for V4L2_FIELD_ANY that is turned into
         * V4L2_FIELD_NONE.
         */
        bpp = ALIGN(fmtinfo->bpp, 8);

        format->width = clamp_t(unsigned int, format->width,
                                CAL_MIN_WIDTH_BYTES * 8 / bpp,
                                CAL_MAX_WIDTH_BYTES * 8 / bpp);
        format->height = clamp_t(unsigned int, format->height,
                                 CAL_MIN_HEIGHT_LINES, CAL_MAX_HEIGHT_LINES);
        format->pixelformat = fmtinfo->fourcc;

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

        /*
         * Calculate the number of bytes per line and the image size. The
         * hardware stores the stride as a number of 16 bytes words, in a
         * signed 15-bit value. Only 14 bits are thus usable.
         */
        format->bytesperline = ALIGN(clamp(format->bytesperline,
                                           format->width * bpp / 8,
                                           ((1U << 14) - 1) * 16), 16);

        format->sizeimage = format->height * format->bytesperline;

        format->colorspace = ctx->v_fmt.fmt.pix.colorspace;

        if (info)
                *info = fmtinfo;

        ctx_dbg(3, ctx, "%s: %p4cc %ux%u (bytesperline %u sizeimage %u)\n",
                __func__, &format->pixelformat,
                format->width, format->height,
                format->bytesperline, format->sizeimage);
}

static int cal_mc_try_fmt_vid_cap(struct file *file, void *priv,
                                  struct v4l2_format *f)
{
        struct cal_ctx *ctx = video_drvdata(file);

        cal_mc_try_fmt(ctx, f, NULL);
        return 0;
}

static int cal_mc_s_fmt_vid_cap(struct file *file, void *priv,
                                struct v4l2_format *f)
{
        struct cal_ctx *ctx = video_drvdata(file);
        const struct cal_format_info *fmtinfo;

        if (vb2_is_busy(&ctx->vb_vidq)) {
                ctx_dbg(3, ctx, "%s device busy\n", __func__);
                return -EBUSY;
        }

        cal_mc_try_fmt(ctx, f, &fmtinfo);

        ctx->v_fmt = *f;
        ctx->fmtinfo = fmtinfo;

        return 0;
}

static int cal_mc_enum_framesizes(struct file *file, void *fh,
                                  struct v4l2_frmsizeenum *fsize)
{
        struct cal_ctx *ctx = video_drvdata(file);
        const struct cal_format_info *fmtinfo;
        unsigned int bpp;

        if (fsize->index > 0)
                return -EINVAL;

        fmtinfo = cal_format_by_fourcc(fsize->pixel_format);
        if (!fmtinfo) {
                ctx_dbg(3, ctx, "Invalid pixel format 0x%08x\n",
                        fsize->pixel_format);
                return -EINVAL;
        }

        bpp = ALIGN(fmtinfo->bpp, 8);

        fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
        fsize->stepwise.min_width = CAL_MIN_WIDTH_BYTES * 8 / bpp;
        fsize->stepwise.max_width = CAL_MAX_WIDTH_BYTES * 8 / bpp;
        fsize->stepwise.step_width = 64 / bpp;
        fsize->stepwise.min_height = CAL_MIN_HEIGHT_LINES;
        fsize->stepwise.max_height = CAL_MAX_HEIGHT_LINES;
        fsize->stepwise.step_height = 1;

        return 0;
}

static const struct v4l2_ioctl_ops cal_ioctl_mc_ops = {
        .vidioc_querycap      = cal_querycap,
        .vidioc_enum_fmt_vid_cap  = cal_mc_enum_fmt_vid_cap,
        .vidioc_g_fmt_vid_cap     = cal_g_fmt_vid_cap,
        .vidioc_try_fmt_vid_cap   = cal_mc_try_fmt_vid_cap,
        .vidioc_s_fmt_vid_cap     = cal_mc_s_fmt_vid_cap,
        .vidioc_enum_framesizes   = cal_mc_enum_framesizes,
        .vidioc_reqbufs       = vb2_ioctl_reqbufs,
        .vidioc_create_bufs   = vb2_ioctl_create_bufs,
        .vidioc_prepare_buf   = vb2_ioctl_prepare_buf,
        .vidioc_querybuf      = vb2_ioctl_querybuf,
        .vidioc_qbuf          = vb2_ioctl_qbuf,
        .vidioc_dqbuf         = vb2_ioctl_dqbuf,
        .vidioc_expbuf        = vb2_ioctl_expbuf,
        .vidioc_streamon      = vb2_ioctl_streamon,
        .vidioc_streamoff     = vb2_ioctl_streamoff,
        .vidioc_log_status    = v4l2_ctrl_log_status,
};

/* ------------------------------------------------------------------
 *      videobuf2 Common Operations
 * ------------------------------------------------------------------
 */

static int cal_queue_setup(struct vb2_queue *vq,
                           unsigned int *nbuffers, unsigned int *nplanes,
                           unsigned int sizes[], struct device *alloc_devs[])
{
        struct cal_ctx *ctx = vb2_get_drv_priv(vq);
        unsigned int size = ctx->v_fmt.fmt.pix.sizeimage;
        unsigned int q_num_bufs = vb2_get_num_buffers(vq);

        if (q_num_bufs + *nbuffers < 3)
                *nbuffers = 3 - q_num_bufs;

        if (*nplanes) {
                if (sizes[0] < size)
                        return -EINVAL;
                size = sizes[0];
        }

        *nplanes = 1;
        sizes[0] = size;

        ctx_dbg(3, ctx, "nbuffers=%d, size=%d\n", *nbuffers, sizes[0]);

        return 0;
}

static int cal_buffer_prepare(struct vb2_buffer *vb)
{
        struct cal_ctx *ctx = vb2_get_drv_priv(vb->vb2_queue);
        struct cal_buffer *buf = container_of(vb, struct cal_buffer,
                                              vb.vb2_buf);
        unsigned long size;

        size = ctx->v_fmt.fmt.pix.sizeimage;
        if (vb2_plane_size(vb, 0) < size) {
                ctx_err(ctx,
                        "data will not fit into plane (%lu < %lu)\n",
                        vb2_plane_size(vb, 0), size);
                return -EINVAL;
        }

        vb2_set_plane_payload(&buf->vb.vb2_buf, 0, size);
        return 0;
}

static void cal_buffer_queue(struct vb2_buffer *vb)
{
        struct cal_ctx *ctx = vb2_get_drv_priv(vb->vb2_queue);
        struct cal_buffer *buf = container_of(vb, struct cal_buffer,
                                              vb.vb2_buf);
        unsigned long flags;

        /* recheck locking */
        spin_lock_irqsave(&ctx->dma.lock, flags);
        list_add_tail(&buf->list, &ctx->dma.queue);
        spin_unlock_irqrestore(&ctx->dma.lock, flags);
}

static void cal_release_buffers(struct cal_ctx *ctx,
                                enum vb2_buffer_state state)
{
        struct cal_buffer *buf, *tmp;

        /* Release all queued buffers. */
        spin_lock_irq(&ctx->dma.lock);

        list_for_each_entry_safe(buf, tmp, &ctx->dma.queue, list) {
                list_del(&buf->list);
                vb2_buffer_done(&buf->vb.vb2_buf, state);
        }

        if (ctx->dma.pending) {
                vb2_buffer_done(&ctx->dma.pending->vb.vb2_buf, state);
                ctx->dma.pending = NULL;
        }

        if (ctx->dma.active) {
                vb2_buffer_done(&ctx->dma.active->vb.vb2_buf, state);
                ctx->dma.active = NULL;
        }

        spin_unlock_irq(&ctx->dma.lock);
}

/* ------------------------------------------------------------------
 *      videobuf2 Operations
 * ------------------------------------------------------------------
 */

static int cal_video_check_format(struct cal_ctx *ctx)
{
        const struct v4l2_mbus_framefmt *format;
        struct v4l2_subdev_state *state;
        struct media_pad *phy_source_pad;
        int ret = 0;

        phy_source_pad = media_pad_remote_pad_first(&ctx->pad);
        if (!phy_source_pad)
                return -ENODEV;

        state = v4l2_subdev_lock_and_get_active_state(&ctx->phy->subdev);

        format = v4l2_subdev_state_get_format(state, phy_source_pad->index, 0);
        if (!format) {
                ret = -EINVAL;
                goto out;
        }

        if (ctx->fmtinfo->code != format->code ||
            ctx->v_fmt.fmt.pix.height != format->height ||
            ctx->v_fmt.fmt.pix.width != format->width ||
            ctx->v_fmt.fmt.pix.field != format->field) {
                ret = -EPIPE;
                goto out;
        }

out:
        v4l2_subdev_unlock_state(state);

        return ret;
}

static int cal_start_streaming(struct vb2_queue *vq, unsigned int count)
{
        struct cal_ctx *ctx = vb2_get_drv_priv(vq);
        struct media_pad *phy_source_pad;
        struct cal_buffer *buf;
        dma_addr_t addr;
        int ret;

        phy_source_pad = media_pad_remote_pad_first(&ctx->pad);
        if (!phy_source_pad) {
                ctx_err(ctx, "Context not connected\n");
                ret = -ENODEV;
                goto error_release_buffers;
        }

        ret = video_device_pipeline_alloc_start(&ctx->vdev);
        if (ret < 0) {
                ctx_err(ctx, "Failed to start media pipeline: %d\n", ret);
                goto error_release_buffers;
        }

        /* Find the PHY connected to this video device */
        if (cal_mc_api)
                ctx->phy = cal_camerarx_get_phy_from_entity(phy_source_pad->entity);

        /*
         * Verify that the currently configured format matches the output of
         * the connected CAMERARX.
         */
        ret = cal_video_check_format(ctx);
        if (ret < 0) {
                ctx_dbg(3, ctx,
                        "Format mismatch between CAMERARX and video node\n");
                goto error_pipeline;
        }

        ret = cal_ctx_prepare(ctx);
        if (ret) {
                ctx_err(ctx, "Failed to prepare context: %d\n", ret);
                goto error_pipeline;
        }

        spin_lock_irq(&ctx->dma.lock);
        buf = list_first_entry(&ctx->dma.queue, struct cal_buffer, list);
        ctx->dma.active = buf;
        list_del(&buf->list);
        spin_unlock_irq(&ctx->dma.lock);

        addr = vb2_dma_contig_plane_dma_addr(&buf->vb.vb2_buf, 0);

        ret = pm_runtime_resume_and_get(ctx->cal->dev);
        if (ret < 0)
                goto error_unprepare;

        cal_ctx_set_dma_addr(ctx, addr);
        cal_ctx_start(ctx);

        ret = v4l2_subdev_enable_streams(&ctx->phy->subdev,
                                         phy_source_pad->index, BIT(0));
        if (ret)
                goto error_stop;

        if (cal_debug >= 4)
                cal_quickdump_regs(ctx->cal);

        return 0;

error_stop:
        cal_ctx_stop(ctx);
        pm_runtime_put_sync(ctx->cal->dev);
error_unprepare:
        cal_ctx_unprepare(ctx);
error_pipeline:
        video_device_pipeline_stop(&ctx->vdev);
error_release_buffers:
        cal_release_buffers(ctx, VB2_BUF_STATE_QUEUED);

        return ret;
}

static void cal_stop_streaming(struct vb2_queue *vq)
{
        struct cal_ctx *ctx = vb2_get_drv_priv(vq);
        struct media_pad *phy_source_pad;

        cal_ctx_stop(ctx);

        phy_source_pad = media_pad_remote_pad_first(&ctx->pad);

        v4l2_subdev_disable_streams(&ctx->phy->subdev, phy_source_pad->index,
                                    BIT(0));

        pm_runtime_put_sync(ctx->cal->dev);

        cal_ctx_unprepare(ctx);

        cal_release_buffers(ctx, VB2_BUF_STATE_ERROR);

        video_device_pipeline_stop(&ctx->vdev);

        if (cal_mc_api)
                ctx->phy = NULL;
}

static const struct vb2_ops cal_video_qops = {
        .queue_setup            = cal_queue_setup,
        .buf_prepare            = cal_buffer_prepare,
        .buf_queue              = cal_buffer_queue,
        .start_streaming        = cal_start_streaming,
        .stop_streaming         = cal_stop_streaming,
};

/* ------------------------------------------------------------------
 *      V4L2 Initialization and Registration
 * ------------------------------------------------------------------
 */

static const struct v4l2_file_operations cal_fops = {
        .owner          = THIS_MODULE,
        .open           = v4l2_fh_open,
        .release        = vb2_fop_release,
        .poll           = vb2_fop_poll,
        .unlocked_ioctl = video_ioctl2, /* V4L2 ioctl handler */
        .mmap           = vb2_fop_mmap,
};

static int cal_ctx_v4l2_init_formats(struct cal_ctx *ctx)
{
        struct v4l2_subdev *sd = ctx->phy->source;
        struct v4l2_mbus_framefmt mbus_fmt;
        const struct cal_format_info *fmtinfo;
        unsigned int i, j, k;
        int ret = 0;

        /* Enumerate sub device formats and enable all matching local formats */
        ctx->active_fmt = devm_kcalloc(ctx->cal->dev, cal_num_formats,
                                       sizeof(*ctx->active_fmt), GFP_KERNEL);
        if (!ctx->active_fmt)
                return -ENOMEM;

        ctx->num_active_fmt = 0;

        for (j = 0, i = 0; ; ++j) {
                struct v4l2_subdev_mbus_code_enum mbus_code = {
                        .index = j,
                        .which = V4L2_SUBDEV_FORMAT_ACTIVE,
                };

                ret = v4l2_subdev_call_state_active(sd, pad, enum_mbus_code,
                                                    &mbus_code);
                if (ret == -EINVAL)
                        break;

                if (ret) {
                        ctx_err(ctx, "Error enumerating mbus codes in subdev %s: %d\n",
                                sd->name, ret);
                        return ret;
                }

                ctx_dbg(2, ctx,
                        "subdev %s: code: %04x idx: %u\n",
                        sd->name, mbus_code.code, j);

                for (k = 0; k < cal_num_formats; k++) {
                        fmtinfo = &cal_formats[k];

                        if (mbus_code.code == fmtinfo->code) {
                                ctx->active_fmt[i] = fmtinfo;
                                ctx_dbg(2, ctx,
                                        "matched fourcc: %p4cc: code: %04x idx: %u\n",
                                        &fmtinfo->fourcc,
                                        fmtinfo->code, i);
                                ctx->num_active_fmt = ++i;
                        }
                }
        }

        if (i == 0) {
                ctx_err(ctx, "No suitable format reported by subdev %s\n",
                        sd->name);
                return -EINVAL;
        }

        ret = __subdev_get_format(ctx, &mbus_fmt);
        if (ret)
                return ret;

        fmtinfo = find_format_by_code(ctx, mbus_fmt.code);
        if (!fmtinfo) {
                ctx_dbg(3, ctx, "mbus code format (0x%08x) not found.\n",
                        mbus_fmt.code);
                return -EINVAL;
        }

        /* Save current format */
        v4l2_fill_pix_format(&ctx->v_fmt.fmt.pix, &mbus_fmt);
        ctx->v_fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
        ctx->v_fmt.fmt.pix.pixelformat = fmtinfo->fourcc;
        cal_calc_format_size(ctx, fmtinfo, &ctx->v_fmt);
        ctx->fmtinfo = fmtinfo;

        return 0;
}

static int cal_ctx_v4l2_init_mc_format(struct cal_ctx *ctx)
{
        const struct cal_format_info *fmtinfo;
        struct v4l2_pix_format *pix_fmt = &ctx->v_fmt.fmt.pix;

        fmtinfo = cal_format_by_code(MEDIA_BUS_FMT_UYVY8_1X16);
        if (!fmtinfo)
                return -EINVAL;

        pix_fmt->width = 640;
        pix_fmt->height = 480;
        pix_fmt->field = V4L2_FIELD_NONE;
        pix_fmt->colorspace = V4L2_COLORSPACE_SRGB;
        pix_fmt->ycbcr_enc = V4L2_YCBCR_ENC_601;
        pix_fmt->quantization = V4L2_QUANTIZATION_LIM_RANGE;
        pix_fmt->xfer_func = V4L2_XFER_FUNC_SRGB;
        pix_fmt->pixelformat = fmtinfo->fourcc;

        ctx->v_fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

        /* Save current format */
        cal_calc_format_size(ctx, fmtinfo, &ctx->v_fmt);
        ctx->fmtinfo = fmtinfo;

        return 0;
}

int cal_ctx_v4l2_register(struct cal_ctx *ctx)
{
        struct video_device *vfd = &ctx->vdev;
        int ret;

        if (!cal_mc_api) {
                struct v4l2_ctrl_handler *hdl = &ctx->ctrl_handler;

                ret = cal_ctx_v4l2_init_formats(ctx);
                if (ret) {
                        ctx_err(ctx, "Failed to init formats: %d\n", ret);
                        return ret;
                }

                ret = v4l2_ctrl_add_handler(hdl, ctx->phy->source->ctrl_handler,
                                            NULL, true);
                if (ret < 0) {
                        ctx_err(ctx, "Failed to add source ctrl handler\n");
                        return ret;
                }
        } else {
                ret = cal_ctx_v4l2_init_mc_format(ctx);
                if (ret) {
                        ctx_err(ctx, "Failed to init format: %d\n", ret);
                        return ret;
                }
        }

        ret = video_register_device(vfd, VFL_TYPE_VIDEO, cal_video_nr);
        if (ret < 0) {
                ctx_err(ctx, "Failed to register video device\n");
                return ret;
        }

        if (cal_mc_api) {
                u16 phy_idx;
                u16 pad_idx;

                /* Create links from all video nodes to all PHYs */

                for (phy_idx = 0; phy_idx < ctx->cal->data->num_csi2_phy;
                     ++phy_idx) {
                        struct media_entity *phy_entity =
                                &ctx->cal->phy[phy_idx]->subdev.entity;

                        for (pad_idx = 1; pad_idx < CAL_CAMERARX_NUM_PADS;
                             ++pad_idx) {
                                /*
                                 * Enable only links from video0 to PHY0 pad 1,
                                 * and video1 to PHY1 pad 1.
                                 */
                                bool enable = (ctx->dma_ctx == 0 &&
                                               phy_idx == 0 && pad_idx == 1) ||
                                              (ctx->dma_ctx == 1 &&
                                               phy_idx == 1 && pad_idx == 1);

                                ret = media_create_pad_link(phy_entity, pad_idx,
                                                            &vfd->entity, 0,
                                                            enable ? MEDIA_LNK_FL_ENABLED : 0);
                                if (ret) {
                                        ctx_err(ctx,
                                                "Failed to create media link for context %u\n",
                                                ctx->dma_ctx);
                                        video_unregister_device(vfd);
                                        return ret;
                                }
                        }
                }
        } else {
                ret = media_create_pad_link(&ctx->phy->subdev.entity,
                                            CAL_CAMERARX_PAD_FIRST_SOURCE,
                                            &vfd->entity, 0,
                                            MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED);
                if (ret) {
                        ctx_err(ctx,
                                "Failed to create media link for context %u\n",
                                ctx->dma_ctx);
                        video_unregister_device(vfd);
                        return ret;
                }
        }

        ctx_info(ctx, "V4L2 device registered as %s\n",
                 video_device_node_name(vfd));

        return 0;
}

void cal_ctx_v4l2_unregister(struct cal_ctx *ctx)
{
        ctx_dbg(1, ctx, "unregistering %s\n",
                video_device_node_name(&ctx->vdev));

        video_unregister_device(&ctx->vdev);
}

int cal_ctx_v4l2_init(struct cal_ctx *ctx)
{
        struct video_device *vfd = &ctx->vdev;
        struct vb2_queue *q = &ctx->vb_vidq;
        int ret;

        INIT_LIST_HEAD(&ctx->dma.queue);
        spin_lock_init(&ctx->dma.lock);
        mutex_init(&ctx->mutex);
        init_waitqueue_head(&ctx->dma.wait);

        /* Initialize the vb2 queue. */
        q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
        q->io_modes = VB2_MMAP | VB2_DMABUF;
        q->drv_priv = ctx;
        q->buf_struct_size = sizeof(struct cal_buffer);
        q->ops = &cal_video_qops;
        q->mem_ops = &vb2_dma_contig_memops;
        q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
        q->lock = &ctx->mutex;
        q->min_queued_buffers = 3;
        q->dev = ctx->cal->dev;

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

        /* Initialize the video device and media entity. */
        vfd->fops = &cal_fops;
        vfd->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING
                         | (cal_mc_api ? V4L2_CAP_IO_MC : 0);
        vfd->v4l2_dev = &ctx->cal->v4l2_dev;
        vfd->queue = q;
        snprintf(vfd->name, sizeof(vfd->name), "CAL output %u", ctx->dma_ctx);
        vfd->release = video_device_release_empty;
        vfd->ioctl_ops = cal_mc_api ? &cal_ioctl_mc_ops : &cal_ioctl_legacy_ops;
        vfd->lock = &ctx->mutex;
        video_set_drvdata(vfd, ctx);

        ctx->pad.flags = MEDIA_PAD_FL_SINK;
        ret = media_entity_pads_init(&vfd->entity, 1, &ctx->pad);
        if (ret < 0)
                return ret;

        if (!cal_mc_api) {
                /* Initialize the control handler. */
                struct v4l2_ctrl_handler *hdl = &ctx->ctrl_handler;

                ret = v4l2_ctrl_handler_init(hdl, 11);
                if (ret < 0) {
                        ctx_err(ctx, "Failed to init ctrl handler\n");
                        goto error;
                }

                vfd->ctrl_handler = hdl;
        }

        return 0;

error:
        media_entity_cleanup(&vfd->entity);
        return ret;
}

void cal_ctx_v4l2_cleanup(struct cal_ctx *ctx)
{
        if (!cal_mc_api)
                v4l2_ctrl_handler_free(&ctx->ctrl_handler);

        media_entity_cleanup(&ctx->vdev.entity);
}