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[mirror_ubuntu-artful-kernel.git] / drivers / media / platform / exynos-gsc / gsc-m2m.c

/*
 * Copyright (c) 2011 - 2012 Samsung Electronics Co., Ltd.
 *              http://www.samsung.com
 *
 * Samsung EXYNOS5 SoC series G-Scaler driver
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published
 * by the Free Software Foundation, either version 2 of the License,
 * or (at your option) any later version.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/bug.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/list.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/clk.h>

#include <media/v4l2-ioctl.h>

#include "gsc-core.h"

static int gsc_m2m_ctx_stop_req(struct gsc_ctx *ctx)
{
        struct gsc_ctx *curr_ctx;
        struct gsc_dev *gsc = ctx->gsc_dev;
        int ret;

        curr_ctx = v4l2_m2m_get_curr_priv(gsc->m2m.m2m_dev);
        if (!gsc_m2m_pending(gsc) || (curr_ctx != ctx))
                return 0;

        gsc_ctx_state_lock_set(GSC_CTX_STOP_REQ, ctx);
        ret = wait_event_timeout(gsc->irq_queue,
                        !gsc_ctx_state_is_set(GSC_CTX_STOP_REQ, ctx),
                        GSC_SHUTDOWN_TIMEOUT);

        return ret == 0 ? -ETIMEDOUT : ret;
}

static void __gsc_m2m_job_abort(struct gsc_ctx *ctx)
{
        int ret;

        ret = gsc_m2m_ctx_stop_req(ctx);
        if ((ret == -ETIMEDOUT) || (ctx->state & GSC_CTX_ABORT)) {
                gsc_ctx_state_lock_clear(GSC_CTX_STOP_REQ | GSC_CTX_ABORT, ctx);
                gsc_m2m_job_finish(ctx, VB2_BUF_STATE_ERROR);
        }
}

static int gsc_m2m_start_streaming(struct vb2_queue *q, unsigned int count)
{
        struct gsc_ctx *ctx = q->drv_priv;
        int ret;

        ret = pm_runtime_get_sync(&ctx->gsc_dev->pdev->dev);
        return ret > 0 ? 0 : ret;
}

static void __gsc_m2m_cleanup_queue(struct gsc_ctx *ctx)
{
        struct vb2_v4l2_buffer *src_vb, *dst_vb;

        while (v4l2_m2m_num_src_bufs_ready(ctx->m2m_ctx) > 0) {
                src_vb = v4l2_m2m_src_buf_remove(ctx->m2m_ctx);
                v4l2_m2m_buf_done(src_vb, VB2_BUF_STATE_ERROR);
        }

        while (v4l2_m2m_num_dst_bufs_ready(ctx->m2m_ctx) > 0) {
                dst_vb = v4l2_m2m_dst_buf_remove(ctx->m2m_ctx);
                v4l2_m2m_buf_done(dst_vb, VB2_BUF_STATE_ERROR);
        }
}

static void gsc_m2m_stop_streaming(struct vb2_queue *q)
{
        struct gsc_ctx *ctx = q->drv_priv;

        __gsc_m2m_job_abort(ctx);

        __gsc_m2m_cleanup_queue(ctx);

        pm_runtime_put(&ctx->gsc_dev->pdev->dev);
}

void gsc_m2m_job_finish(struct gsc_ctx *ctx, int vb_state)
{
        struct vb2_v4l2_buffer *src_vb, *dst_vb;

        if (!ctx || !ctx->m2m_ctx)
                return;

        src_vb = v4l2_m2m_src_buf_remove(ctx->m2m_ctx);
        dst_vb = v4l2_m2m_dst_buf_remove(ctx->m2m_ctx);

        if (src_vb && dst_vb) {
                dst_vb->vb2_buf.timestamp = src_vb->vb2_buf.timestamp;
                dst_vb->timecode = src_vb->timecode;
                dst_vb->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK;
                dst_vb->flags |=
                        src_vb->flags
                        & V4L2_BUF_FLAG_TSTAMP_SRC_MASK;

                v4l2_m2m_buf_done(src_vb, vb_state);
                v4l2_m2m_buf_done(dst_vb, vb_state);

                v4l2_m2m_job_finish(ctx->gsc_dev->m2m.m2m_dev,
                                    ctx->m2m_ctx);
        }
}

static void gsc_m2m_job_abort(void *priv)
{
        __gsc_m2m_job_abort((struct gsc_ctx *)priv);
}

static int gsc_get_bufs(struct gsc_ctx *ctx)
{
        struct gsc_frame *s_frame, *d_frame;
        struct vb2_v4l2_buffer *src_vb, *dst_vb;
        int ret;

        s_frame = &ctx->s_frame;
        d_frame = &ctx->d_frame;

        src_vb = v4l2_m2m_next_src_buf(ctx->m2m_ctx);
        ret = gsc_prepare_addr(ctx, &src_vb->vb2_buf, s_frame, &s_frame->addr);
        if (ret)
                return ret;

        dst_vb = v4l2_m2m_next_dst_buf(ctx->m2m_ctx);
        ret = gsc_prepare_addr(ctx, &dst_vb->vb2_buf, d_frame, &d_frame->addr);
        if (ret)
                return ret;

        dst_vb->vb2_buf.timestamp = src_vb->vb2_buf.timestamp;

        return 0;
}

static void gsc_m2m_device_run(void *priv)
{
        struct gsc_ctx *ctx = priv;
        struct gsc_dev *gsc;
        unsigned long flags;
        int ret;
        bool is_set = false;

        if (WARN(!ctx, "null hardware context\n"))
                return;

        gsc = ctx->gsc_dev;
        spin_lock_irqsave(&gsc->slock, flags);

        set_bit(ST_M2M_PEND, &gsc->state);

        /* Reconfigure hardware if the context has changed. */
        if (gsc->m2m.ctx != ctx) {
                pr_debug("gsc->m2m.ctx = 0x%p, current_ctx = 0x%p",
                                gsc->m2m.ctx, ctx);
                ctx->state |= GSC_PARAMS;
                gsc->m2m.ctx = ctx;
        }

        is_set = ctx->state & GSC_CTX_STOP_REQ;
        if (is_set) {
                ctx->state &= ~GSC_CTX_STOP_REQ;
                ctx->state |= GSC_CTX_ABORT;
                wake_up(&gsc->irq_queue);
                goto put_device;
        }

        ret = gsc_get_bufs(ctx);
        if (ret) {
                pr_err("Wrong address");
                goto put_device;
        }

        gsc_set_prefbuf(gsc, &ctx->s_frame);
        gsc_hw_set_input_addr(gsc, &ctx->s_frame.addr, GSC_M2M_BUF_NUM);
        gsc_hw_set_output_addr(gsc, &ctx->d_frame.addr, GSC_M2M_BUF_NUM);

        if (ctx->state & GSC_PARAMS) {
                gsc_hw_set_input_buf_masking(gsc, GSC_M2M_BUF_NUM, false);
                gsc_hw_set_output_buf_masking(gsc, GSC_M2M_BUF_NUM, false);
                gsc_hw_set_frm_done_irq_mask(gsc, false);
                gsc_hw_set_gsc_irq_enable(gsc, true);

                if (gsc_set_scaler_info(ctx)) {
                        pr_err("Scaler setup error");
                        goto put_device;
                }

                gsc_hw_set_input_path(ctx);
                gsc_hw_set_in_size(ctx);
                gsc_hw_set_in_image_format(ctx);

                gsc_hw_set_output_path(ctx);
                gsc_hw_set_out_size(ctx);
                gsc_hw_set_out_image_format(ctx);

                gsc_hw_set_prescaler(ctx);
                gsc_hw_set_mainscaler(ctx);
                gsc_hw_set_rotation(ctx);
                gsc_hw_set_global_alpha(ctx);
        }

        /* update shadow registers */
        gsc_hw_set_sfr_update(ctx);

        ctx->state &= ~GSC_PARAMS;
        gsc_hw_enable_control(gsc, true);

        spin_unlock_irqrestore(&gsc->slock, flags);
        return;

put_device:
        ctx->state &= ~GSC_PARAMS;
        spin_unlock_irqrestore(&gsc->slock, flags);
}

static int gsc_m2m_queue_setup(struct vb2_queue *vq,
                        unsigned int *num_buffers, unsigned int *num_planes,
                        unsigned int sizes[], struct device *alloc_devs[])
{
        struct gsc_ctx *ctx = vb2_get_drv_priv(vq);
        struct gsc_frame *frame;
        int i;

        frame = ctx_get_frame(ctx, vq->type);
        if (IS_ERR(frame))
                return PTR_ERR(frame);

        if (!frame->fmt)
                return -EINVAL;

        *num_planes = frame->fmt->num_planes;
        for (i = 0; i < frame->fmt->num_planes; i++)
                sizes[i] = frame->payload[i];
        return 0;
}

static int gsc_m2m_buf_prepare(struct vb2_buffer *vb)
{
        struct gsc_ctx *ctx = vb2_get_drv_priv(vb->vb2_queue);
        struct gsc_frame *frame;
        int i;

        frame = ctx_get_frame(ctx, vb->vb2_queue->type);
        if (IS_ERR(frame))
                return PTR_ERR(frame);

        if (!V4L2_TYPE_IS_OUTPUT(vb->vb2_queue->type)) {
                for (i = 0; i < frame->fmt->num_planes; i++)
                        vb2_set_plane_payload(vb, i, frame->payload[i]);
        }

        return 0;
}

static void gsc_m2m_buf_queue(struct vb2_buffer *vb)
{
        struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
        struct gsc_ctx *ctx = vb2_get_drv_priv(vb->vb2_queue);

        pr_debug("ctx: %p, ctx->state: 0x%x", ctx, ctx->state);

        if (ctx->m2m_ctx)
                v4l2_m2m_buf_queue(ctx->m2m_ctx, vbuf);
}

static const struct vb2_ops gsc_m2m_qops = {
        .queue_setup     = gsc_m2m_queue_setup,
        .buf_prepare     = gsc_m2m_buf_prepare,
        .buf_queue       = gsc_m2m_buf_queue,
        .wait_prepare    = vb2_ops_wait_prepare,
        .wait_finish     = vb2_ops_wait_finish,
        .stop_streaming  = gsc_m2m_stop_streaming,
        .start_streaming = gsc_m2m_start_streaming,
};

static int gsc_m2m_querycap(struct file *file, void *fh,
                           struct v4l2_capability *cap)
{
        struct gsc_ctx *ctx = fh_to_ctx(fh);
        struct gsc_dev *gsc = ctx->gsc_dev;

        strlcpy(cap->driver, GSC_MODULE_NAME, sizeof(cap->driver));
        strlcpy(cap->card, GSC_MODULE_NAME " gscaler", sizeof(cap->card));
        snprintf(cap->bus_info, sizeof(cap->bus_info), "platform:%s",
                 dev_name(&gsc->pdev->dev));
        cap->device_caps = V4L2_CAP_STREAMING | V4L2_CAP_VIDEO_M2M_MPLANE |
                V4L2_CAP_VIDEO_CAPTURE_MPLANE | V4L2_CAP_VIDEO_OUTPUT_MPLANE;

        cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
        return 0;
}

static int gsc_m2m_enum_fmt_mplane(struct file *file, void *priv,
                                struct v4l2_fmtdesc *f)
{
        return gsc_enum_fmt_mplane(f);
}

static int gsc_m2m_g_fmt_mplane(struct file *file, void *fh,
                             struct v4l2_format *f)
{
        struct gsc_ctx *ctx = fh_to_ctx(fh);

        return gsc_g_fmt_mplane(ctx, f);
}

static int gsc_m2m_try_fmt_mplane(struct file *file, void *fh,
                                  struct v4l2_format *f)
{
        struct gsc_ctx *ctx = fh_to_ctx(fh);

        return gsc_try_fmt_mplane(ctx, f);
}

static int gsc_m2m_s_fmt_mplane(struct file *file, void *fh,
                                 struct v4l2_format *f)
{
        struct gsc_ctx *ctx = fh_to_ctx(fh);
        struct vb2_queue *vq;
        struct gsc_frame *frame;
        struct v4l2_pix_format_mplane *pix;
        int i, ret = 0;

        ret = gsc_m2m_try_fmt_mplane(file, fh, f);
        if (ret)
                return ret;

        vq = v4l2_m2m_get_vq(ctx->m2m_ctx, f->type);

        if (vb2_is_streaming(vq)) {
                pr_err("queue (%d) busy", f->type);
                return -EBUSY;
        }

        if (V4L2_TYPE_IS_OUTPUT(f->type))
                frame = &ctx->s_frame;
        else
                frame = &ctx->d_frame;

        pix = &f->fmt.pix_mp;
        frame->fmt = find_fmt(&pix->pixelformat, NULL, 0);
        frame->colorspace = pix->colorspace;
        if (!frame->fmt)
                return -EINVAL;

        for (i = 0; i < frame->fmt->num_planes; i++)
                frame->payload[i] = pix->plane_fmt[i].sizeimage;

        gsc_set_frame_size(frame, pix->width, pix->height);

        if (f->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE)
                gsc_ctx_state_lock_set(GSC_PARAMS | GSC_DST_FMT, ctx);
        else
                gsc_ctx_state_lock_set(GSC_PARAMS | GSC_SRC_FMT, ctx);

        pr_debug("f_w: %d, f_h: %d", frame->f_width, frame->f_height);

        return 0;
}

static int gsc_m2m_reqbufs(struct file *file, void *fh,
                          struct v4l2_requestbuffers *reqbufs)
{
        struct gsc_ctx *ctx = fh_to_ctx(fh);
        struct gsc_dev *gsc = ctx->gsc_dev;
        u32 max_cnt;

        max_cnt = (reqbufs->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) ?
                gsc->variant->in_buf_cnt : gsc->variant->out_buf_cnt;
        if (reqbufs->count > max_cnt)
                return -EINVAL;

        return v4l2_m2m_reqbufs(file, ctx->m2m_ctx, reqbufs);
}

static int gsc_m2m_expbuf(struct file *file, void *fh,
                                struct v4l2_exportbuffer *eb)
{
        struct gsc_ctx *ctx = fh_to_ctx(fh);
        return v4l2_m2m_expbuf(file, ctx->m2m_ctx, eb);
}

static int gsc_m2m_querybuf(struct file *file, void *fh,
                                        struct v4l2_buffer *buf)
{
        struct gsc_ctx *ctx = fh_to_ctx(fh);
        return v4l2_m2m_querybuf(file, ctx->m2m_ctx, buf);
}

static int gsc_m2m_qbuf(struct file *file, void *fh,
                          struct v4l2_buffer *buf)
{
        struct gsc_ctx *ctx = fh_to_ctx(fh);
        return v4l2_m2m_qbuf(file, ctx->m2m_ctx, buf);
}

static int gsc_m2m_dqbuf(struct file *file, void *fh,
                           struct v4l2_buffer *buf)
{
        struct gsc_ctx *ctx = fh_to_ctx(fh);
        return v4l2_m2m_dqbuf(file, ctx->m2m_ctx, buf);
}

static int gsc_m2m_streamon(struct file *file, void *fh,
                           enum v4l2_buf_type type)
{
        struct gsc_ctx *ctx = fh_to_ctx(fh);

        /* The source and target color format need to be set */
        if (V4L2_TYPE_IS_OUTPUT(type)) {
                if (!gsc_ctx_state_is_set(GSC_SRC_FMT, ctx))
                        return -EINVAL;
        } else if (!gsc_ctx_state_is_set(GSC_DST_FMT, ctx)) {
                return -EINVAL;
        }

        return v4l2_m2m_streamon(file, ctx->m2m_ctx, type);
}

static int gsc_m2m_streamoff(struct file *file, void *fh,
                            enum v4l2_buf_type type)
{
        struct gsc_ctx *ctx = fh_to_ctx(fh);
        return v4l2_m2m_streamoff(file, ctx->m2m_ctx, type);
}

/* Return 1 if rectangle a is enclosed in rectangle b, or 0 otherwise. */
static int is_rectangle_enclosed(struct v4l2_rect *a, struct v4l2_rect *b)
{
        if (a->left < b->left || a->top < b->top)
                return 0;

        if (a->left + a->width > b->left + b->width)
                return 0;

        if (a->top + a->height > b->top + b->height)
                return 0;

        return 1;
}

static int gsc_m2m_g_selection(struct file *file, void *fh,
                        struct v4l2_selection *s)
{
        struct gsc_frame *frame;
        struct gsc_ctx *ctx = fh_to_ctx(fh);

        if ((s->type != V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) &&
            (s->type != V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE))
                return -EINVAL;

        frame = ctx_get_frame(ctx, s->type);
        if (IS_ERR(frame))
                return PTR_ERR(frame);

        switch (s->target) {
        case V4L2_SEL_TGT_COMPOSE_DEFAULT:
        case V4L2_SEL_TGT_COMPOSE_BOUNDS:
        case V4L2_SEL_TGT_CROP_BOUNDS:
        case V4L2_SEL_TGT_CROP_DEFAULT:
                s->r.left = 0;
                s->r.top = 0;
                s->r.width = frame->f_width;
                s->r.height = frame->f_height;
                return 0;

        case V4L2_SEL_TGT_COMPOSE:
        case V4L2_SEL_TGT_CROP:
                s->r.left = frame->crop.left;
                s->r.top = frame->crop.top;
                s->r.width = frame->crop.width;
                s->r.height = frame->crop.height;
                return 0;
        }

        return -EINVAL;
}

static int gsc_m2m_s_selection(struct file *file, void *fh,
                                struct v4l2_selection *s)
{
        struct gsc_frame *frame;
        struct gsc_ctx *ctx = fh_to_ctx(fh);
        struct v4l2_crop cr;
        struct gsc_variant *variant = ctx->gsc_dev->variant;
        int ret;

        cr.type = s->type;
        cr.c = s->r;

        if ((s->type != V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) &&
            (s->type != V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE))
                return -EINVAL;

        ret = gsc_try_crop(ctx, &cr);
        if (ret)
                return ret;

        if (s->flags & V4L2_SEL_FLAG_LE &&
            !is_rectangle_enclosed(&cr.c, &s->r))
                return -ERANGE;

        if (s->flags & V4L2_SEL_FLAG_GE &&
            !is_rectangle_enclosed(&s->r, &cr.c))
                return -ERANGE;

        s->r = cr.c;

        switch (s->target) {
        case V4L2_SEL_TGT_COMPOSE_BOUNDS:
        case V4L2_SEL_TGT_COMPOSE_DEFAULT:
        case V4L2_SEL_TGT_COMPOSE:
                frame = &ctx->s_frame;
                break;

        case V4L2_SEL_TGT_CROP_BOUNDS:
        case V4L2_SEL_TGT_CROP:
        case V4L2_SEL_TGT_CROP_DEFAULT:
                frame = &ctx->d_frame;
                break;

        default:
                return -EINVAL;
        }

        /* Check to see if scaling ratio is within supported range */
        if (gsc_ctx_state_is_set(GSC_DST_FMT | GSC_SRC_FMT, ctx)) {
                if (s->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) {
                        ret = gsc_check_scaler_ratio(variant, cr.c.width,
                                cr.c.height, ctx->d_frame.crop.width,
                                ctx->d_frame.crop.height,
                                ctx->gsc_ctrls.rotate->val, ctx->out_path);
                } else {
                        ret = gsc_check_scaler_ratio(variant,
                                ctx->s_frame.crop.width,
                                ctx->s_frame.crop.height, cr.c.width,
                                cr.c.height, ctx->gsc_ctrls.rotate->val,
                                ctx->out_path);
                }

                if (ret) {
                        pr_err("Out of scaler range");
                        return -EINVAL;
                }
        }

        frame->crop = cr.c;

        gsc_ctx_state_lock_set(GSC_PARAMS, ctx);
        return 0;
}

static const struct v4l2_ioctl_ops gsc_m2m_ioctl_ops = {
        .vidioc_querycap                = gsc_m2m_querycap,
        .vidioc_enum_fmt_vid_cap_mplane = gsc_m2m_enum_fmt_mplane,
        .vidioc_enum_fmt_vid_out_mplane = gsc_m2m_enum_fmt_mplane,
        .vidioc_g_fmt_vid_cap_mplane    = gsc_m2m_g_fmt_mplane,
        .vidioc_g_fmt_vid_out_mplane    = gsc_m2m_g_fmt_mplane,
        .vidioc_try_fmt_vid_cap_mplane  = gsc_m2m_try_fmt_mplane,
        .vidioc_try_fmt_vid_out_mplane  = gsc_m2m_try_fmt_mplane,
        .vidioc_s_fmt_vid_cap_mplane    = gsc_m2m_s_fmt_mplane,
        .vidioc_s_fmt_vid_out_mplane    = gsc_m2m_s_fmt_mplane,
        .vidioc_reqbufs                 = gsc_m2m_reqbufs,
        .vidioc_expbuf                  = gsc_m2m_expbuf,
        .vidioc_querybuf                = gsc_m2m_querybuf,
        .vidioc_qbuf                    = gsc_m2m_qbuf,
        .vidioc_dqbuf                   = gsc_m2m_dqbuf,
        .vidioc_streamon                = gsc_m2m_streamon,
        .vidioc_streamoff               = gsc_m2m_streamoff,
        .vidioc_g_selection             = gsc_m2m_g_selection,
        .vidioc_s_selection             = gsc_m2m_s_selection
};

static int queue_init(void *priv, struct vb2_queue *src_vq,
                        struct vb2_queue *dst_vq)
{
        struct gsc_ctx *ctx = priv;
        int ret;

        memset(src_vq, 0, sizeof(*src_vq));
        src_vq->type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
        src_vq->io_modes = VB2_MMAP | VB2_USERPTR | VB2_DMABUF;
        src_vq->drv_priv = ctx;
        src_vq->ops = &gsc_m2m_qops;
        src_vq->mem_ops = &vb2_dma_contig_memops;
        src_vq->buf_struct_size = sizeof(struct v4l2_m2m_buffer);
        src_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
        src_vq->lock = &ctx->gsc_dev->lock;
        src_vq->dev = &ctx->gsc_dev->pdev->dev;

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

        memset(dst_vq, 0, sizeof(*dst_vq));
        dst_vq->type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
        dst_vq->io_modes = VB2_MMAP | VB2_USERPTR | VB2_DMABUF;
        dst_vq->drv_priv = ctx;
        dst_vq->ops = &gsc_m2m_qops;
        dst_vq->mem_ops = &vb2_dma_contig_memops;
        dst_vq->buf_struct_size = sizeof(struct v4l2_m2m_buffer);
        dst_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
        dst_vq->lock = &ctx->gsc_dev->lock;
        dst_vq->dev = &ctx->gsc_dev->pdev->dev;

        return vb2_queue_init(dst_vq);
}

static int gsc_m2m_open(struct file *file)
{
        struct gsc_dev *gsc = video_drvdata(file);
        struct gsc_ctx *ctx = NULL;
        int ret;

        pr_debug("pid: %d, state: 0x%lx", task_pid_nr(current), gsc->state);

        if (mutex_lock_interruptible(&gsc->lock))
                return -ERESTARTSYS;

        ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
        if (!ctx) {
                ret = -ENOMEM;
                goto unlock;
        }

        v4l2_fh_init(&ctx->fh, gsc->m2m.vfd);
        ret = gsc_ctrls_create(ctx);
        if (ret)
                goto error_fh;

        /* Use separate control handler per file handle */
        ctx->fh.ctrl_handler = &ctx->ctrl_handler;
        file->private_data = &ctx->fh;
        v4l2_fh_add(&ctx->fh);

        ctx->gsc_dev = gsc;
        /* Default color format */
        ctx->s_frame.fmt = get_format(0);
        ctx->d_frame.fmt = get_format(0);
        /* Setup the device context for mem2mem mode. */
        ctx->state = GSC_CTX_M2M;
        ctx->flags = 0;
        ctx->in_path = GSC_DMA;
        ctx->out_path = GSC_DMA;

        ctx->m2m_ctx = v4l2_m2m_ctx_init(gsc->m2m.m2m_dev, ctx, queue_init);
        if (IS_ERR(ctx->m2m_ctx)) {
                pr_err("Failed to initialize m2m context");
                ret = PTR_ERR(ctx->m2m_ctx);
                goto error_ctrls;
        }

        if (gsc->m2m.refcnt++ == 0)
                set_bit(ST_M2M_OPEN, &gsc->state);

        pr_debug("gsc m2m driver is opened, ctx(0x%p)", ctx);

        mutex_unlock(&gsc->lock);
        return 0;

error_ctrls:
        gsc_ctrls_delete(ctx);
error_fh:
        v4l2_fh_del(&ctx->fh);
        v4l2_fh_exit(&ctx->fh);
        kfree(ctx);
unlock:
        mutex_unlock(&gsc->lock);
        return ret;
}

static int gsc_m2m_release(struct file *file)
{
        struct gsc_ctx *ctx = fh_to_ctx(file->private_data);
        struct gsc_dev *gsc = ctx->gsc_dev;

        pr_debug("pid: %d, state: 0x%lx, refcnt= %d",
                task_pid_nr(current), gsc->state, gsc->m2m.refcnt);

        mutex_lock(&gsc->lock);

        v4l2_m2m_ctx_release(ctx->m2m_ctx);
        gsc_ctrls_delete(ctx);
        v4l2_fh_del(&ctx->fh);
        v4l2_fh_exit(&ctx->fh);

        if (--gsc->m2m.refcnt <= 0)
                clear_bit(ST_M2M_OPEN, &gsc->state);
        kfree(ctx);

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

static unsigned int gsc_m2m_poll(struct file *file,
                                        struct poll_table_struct *wait)
{
        struct gsc_ctx *ctx = fh_to_ctx(file->private_data);
        struct gsc_dev *gsc = ctx->gsc_dev;
        unsigned int ret;

        if (mutex_lock_interruptible(&gsc->lock))
                return -ERESTARTSYS;

        ret = v4l2_m2m_poll(file, ctx->m2m_ctx, wait);
        mutex_unlock(&gsc->lock);

        return ret;
}

static int gsc_m2m_mmap(struct file *file, struct vm_area_struct *vma)
{
        struct gsc_ctx *ctx = fh_to_ctx(file->private_data);
        struct gsc_dev *gsc = ctx->gsc_dev;
        int ret;

        if (mutex_lock_interruptible(&gsc->lock))
                return -ERESTARTSYS;

        ret = v4l2_m2m_mmap(file, ctx->m2m_ctx, vma);
        mutex_unlock(&gsc->lock);

        return ret;
}

static const struct v4l2_file_operations gsc_m2m_fops = {
        .owner          = THIS_MODULE,
        .open           = gsc_m2m_open,
        .release        = gsc_m2m_release,
        .poll           = gsc_m2m_poll,
        .unlocked_ioctl = video_ioctl2,
        .mmap           = gsc_m2m_mmap,
};

static struct v4l2_m2m_ops gsc_m2m_ops = {
        .device_run     = gsc_m2m_device_run,
        .job_abort      = gsc_m2m_job_abort,
};

int gsc_register_m2m_device(struct gsc_dev *gsc)
{
        struct platform_device *pdev;
        int ret;

        if (!gsc)
                return -ENODEV;

        pdev = gsc->pdev;

        gsc->vdev.fops          = &gsc_m2m_fops;
        gsc->vdev.ioctl_ops     = &gsc_m2m_ioctl_ops;
        gsc->vdev.release       = video_device_release_empty;
        gsc->vdev.lock          = &gsc->lock;
        gsc->vdev.vfl_dir       = VFL_DIR_M2M;
        gsc->vdev.v4l2_dev      = &gsc->v4l2_dev;
        snprintf(gsc->vdev.name, sizeof(gsc->vdev.name), "%s.%d:m2m",
                                        GSC_MODULE_NAME, gsc->id);

        video_set_drvdata(&gsc->vdev, gsc);

        gsc->m2m.vfd = &gsc->vdev;
        gsc->m2m.m2m_dev = v4l2_m2m_init(&gsc_m2m_ops);
        if (IS_ERR(gsc->m2m.m2m_dev)) {
                dev_err(&pdev->dev, "failed to initialize v4l2-m2m device\n");
                return PTR_ERR(gsc->m2m.m2m_dev);
        }

        ret = video_register_device(&gsc->vdev, VFL_TYPE_GRABBER, -1);
        if (ret) {
                dev_err(&pdev->dev,
                         "%s(): failed to register video device\n", __func__);
                goto err_m2m_release;
        }

        pr_debug("gsc m2m driver registered as /dev/video%d", gsc->vdev.num);
        return 0;

err_m2m_release:
        v4l2_m2m_release(gsc->m2m.m2m_dev);

        return ret;
}

void gsc_unregister_m2m_device(struct gsc_dev *gsc)
{
        if (gsc) {
                v4l2_m2m_release(gsc->m2m.m2m_dev);
                video_unregister_device(&gsc->vdev);
        }
}