[v3,4/5] media: gscaler: Add m2m functionality for the G-Scaler driver

Commit Message

Shaik Ameer Basha July 25, 2012, 12:26 p.m. UTC

From: Sungchun Kang <[e-mail]>

This patch adds the memory to memory (m2m) interface functionality
for the G-Scaler driver.

Signed-off-by: Hynwoong Kim <[e-mail]>
Signed-off-by: Sungchun Kang <[e-mail]>
Signed-off-by: Shaik Ameer Basha <[e-mail]>
---
 drivers/media/video/exynos-gsc/gsc-m2m.c |  781 ++++++++++++++++++++++++++++++
 1 files changed, 781 insertions(+), 0 deletions(-)
 create mode 100644 drivers/media/video/exynos-gsc/gsc-m2m.c

Comments

Sylwester Nawrocki July 25, 2012, 9:31 p.m. UTC | #1

On 07/25/2012 02:26 PM, Shaik Ameer Basha wrote:
> From: Sungchun Kang<[e-mail]>
>
> This patch adds the memory to memory (m2m) interface functionality
> for the G-Scaler driver.
>
> Signed-off-by: Hynwoong Kim<[e-mail]>
> Signed-off-by: Sungchun Kang<[e-mail]>
> Signed-off-by: Shaik Ameer Basha<[e-mail]>
> ---
>   drivers/media/video/exynos-gsc/gsc-m2m.c |  781 ++++++++++++++++++++++++++++++
>   1 files changed, 781 insertions(+), 0 deletions(-)
>   create mode 100644 drivers/media/video/exynos-gsc/gsc-m2m.c
>
> diff --git a/drivers/media/video/exynos-gsc/gsc-m2m.c b/drivers/media/video/exynos-gsc/gsc-m2m.c
> new file mode 100644
> index 0000000..3568d6f
> --- /dev/null
> +++ b/drivers/media/video/exynos-gsc/gsc-m2m.c
> @@ -0,0 +1,781 @@
> +/*
> + * 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/version.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 = 0;

Unneded initialization.

> +
> +	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 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 int gsc_m2m_stop_streaming(struct vb2_queue *q)
> +{
> +	struct gsc_ctx *ctx = q->drv_priv;
> +	int ret;
> +
> +	ret = gsc_m2m_ctx_stop_req(ctx);
> +	if (ret == -ETIMEDOUT)
> +		gsc_m2m_job_finish(ctx, VB2_BUF_STATE_ERROR);
> +
> +	pm_runtime_put(&ctx->gsc_dev->pdev->dev);
> +
> +	return 0;
> +}
> +
> +void gsc_m2m_job_finish(struct gsc_ctx *ctx, int vb_state)
> +{
> +	struct vb2_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) {
> +		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)
> +{
> +	struct gsc_ctx *ctx = priv;
> +	int ret;
> +
> +	ret = gsc_m2m_ctx_stop_req(ctx);
> +	if (ret == -ETIMEDOUT)
> +		gsc_m2m_job_finish(ctx, VB2_BUF_STATE_ERROR);
> +}
> +
> +int gsc_fill_addr(struct gsc_ctx *ctx)
> +{
> +	struct gsc_frame *s_frame, *d_frame;
> +	struct vb2_buffer *vb = NULL;
> +	int ret = 0;

Unneeded initialization.

> +
> +	s_frame =&ctx->s_frame;
> +	d_frame =&ctx->d_frame;
> +
> +	vb = v4l2_m2m_next_src_buf(ctx->m2m_ctx);
> +	ret = gsc_prepare_addr(ctx, vb, s_frame,&s_frame->addr);
> +	if (ret)
> +		return ret;
> +
> +	vb = v4l2_m2m_next_dst_buf(ctx->m2m_ctx);
> +	ret = gsc_prepare_addr(ctx, vb, d_frame,&d_frame->addr);
> +
> +	return ret;

Just do:

	return gsc_prepare_addr(ctx, vb, d_frame,&d_frame->addr);
> +}
> +
> +static void gsc_m2m_device_run(void *priv)
> +{
> +	struct gsc_ctx *ctx = priv;
> +	struct gsc_dev *gsc;
> +	unsigned long flags;
> +	u32 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) ? 1 : 0;
> +	ctx->state&= ~GSC_CTX_STOP_REQ;
> +	if (is_set) {
> +		wake_up(&gsc->irq_queue);
> +		goto put_device;
> +	}
> +
> +	ret = gsc_fill_addr(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,
> +			const struct v4l2_format *fmt,
> +			unsigned int *num_buffers, unsigned int *num_planes,
> +			unsigned int sizes[], void *allocators[])
> +{
> +	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];
> +		allocators[i] = ctx->gsc_dev->alloc_ctx;
> +	}
> +	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 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, vb);
> +}
> +
> +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	 = gsc_unlock,
> +	.wait_finish	 = gsc_lock,
> +	.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->pdev->name, sizeof(cap->driver));
> +	strlcpy(cap->card, gsc->pdev->name, sizeof(cap->card));
> +	strlcpy(cap->bus_info, "platform", sizeof(cap->bus_info));
> +	cap->device_caps = V4L2_CAP_STREAMING |
> +				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;
> +	struct gsc_frame *frame;
> +	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;
> +	} else if (reqbufs->count == 0) {
> +		if (reqbufs->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)
> +			gsc_ctx_state_lock_clear(GSC_SRC_FMT, ctx);
> +		else
> +			gsc_ctx_state_lock_clear(GSC_DST_FMT, ctx);
> +	}
> +
> +	frame = ctx_get_frame(ctx, reqbufs->type);
> +
> +	return v4l2_m2m_reqbufs(file, ctx->m2m_ctx, reqbufs);
> +}
> +
> +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_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;
> +	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);
> +
> +	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;
> +	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);
> +
> +	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);
> +
> +	if (mutex_lock_interruptible(&gsc->lock))
> +		return -ERESTARTSYS;
> +
> +	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;
> +	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 video_device *vfd;
> +	struct platform_device *pdev;
> +	int ret = 0;
> +
> +	if (!gsc)
> +		return -ENODEV;
> +
> +	pdev = gsc->pdev;
> +
> +	vfd = video_device_alloc();
> +	if (!vfd) {
> +		dev_err(&pdev->dev, "Failed to allocate video device\n");
> +		return -ENOMEM;
> +	}

You could embed struct video_device into struct gsc_dev, rather than
dynamically allocating it...

> +
> +	vfd->fops	=&gsc_m2m_fops;
> +	vfd->ioctl_ops	=&gsc_m2m_ioctl_ops;
> +	vfd->release	= video_device_release;

...and then change that to

	vfd->release	= video_device_release_empty;

> +	vfd->lock	=&gsc->lock;
> +	snprintf(vfd->name, sizeof(vfd->name), "%s.%d:m2m",
> +					GSC_MODULE_NAME, gsc->id);
> +
> +	video_set_drvdata(vfd, gsc);
> +
> +	gsc->m2m.vfd = vfd;
> +	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");
> +		ret = PTR_ERR(gsc->m2m.m2m_dev);
> +		goto err_m2m_r1;
> +	}
> +
> +	ret = video_register_device(vfd, VFL_TYPE_GRABBER, -1);
> +	if (ret) {
> +		dev_err(&pdev->dev,
> +			 "%s(): failed to register video device\n", __func__);
> +		goto err_m2m_r2;
> +	}
> +
> +	pr_debug("gsc m2m driver registered as /dev/video%d", vfd->num);
> +	return 0;
> +
> +err_m2m_r2:
> +	v4l2_m2m_release(gsc->m2m.m2m_dev);
> +err_m2m_r1:
> +	video_device_release(gsc->m2m.vfd);
> +
> +	return ret;
> +}
> +
> +void gsc_unregister_m2m_device(struct gsc_dev *gsc)
> +{
> +	if (gsc)
> +		v4l2_m2m_release(gsc->m2m.m2m_dev);
> +}

Reviewed-by: Sylwester Nawrocki <[e-mail]>

--

Thanks,
Sylwester
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Shaik Ameer Basha July 26, 2012, 3:57 a.m. UTC | #2

Hi Sylwester,

On Thu, Jul 26, 2012 at 3:01 AM, Sylwester Nawrocki
<[e-mail]> wrote:
> On 07/25/2012 02:26 PM, Shaik Ameer Basha wrote:
>>
>> From: Sungchun Kang<[e-mail]>
>>
>> This patch adds the memory to memory (m2m) interface functionality
>> for the G-Scaler driver.
>>
>> Signed-off-by: Hynwoong Kim<[e-mail]>
>> Signed-off-by: Sungchun Kang<[e-mail]>
>> Signed-off-by: Shaik Ameer Basha<[e-mail]>
>> ---
>>   drivers/media/video/exynos-gsc/gsc-m2m.c |  781
>> ++++++++++++++++++++++++++++++
>>   1 files changed, 781 insertions(+), 0 deletions(-)
>>   create mode 100644 drivers/media/video/exynos-gsc/gsc-m2m.c
>>
>> diff --git a/drivers/media/video/exynos-gsc/gsc-m2m.c
>> b/drivers/media/video/exynos-gsc/gsc-m2m.c
>> new file mode 100644
>> index 0000000..3568d6f
>> --- /dev/null
>> +++ b/drivers/media/video/exynos-gsc/gsc-m2m.c
>> @@ -0,0 +1,781 @@
>> +/*
>> + * 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/version.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 = 0;
>
>
> Unneded initialization.
>

Ok. I will fix this for all other unneeded initialization too...

>> +
>> +       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 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 int gsc_m2m_stop_streaming(struct vb2_queue *q)
>> +{
>> +       struct gsc_ctx *ctx = q->drv_priv;
>> +       int ret;
>> +
>> +       ret = gsc_m2m_ctx_stop_req(ctx);
>> +       if (ret == -ETIMEDOUT)
>> +               gsc_m2m_job_finish(ctx, VB2_BUF_STATE_ERROR);
>> +
>> +       pm_runtime_put(&ctx->gsc_dev->pdev->dev);
>> +
>> +       return 0;
>> +}
>> +
>> +void gsc_m2m_job_finish(struct gsc_ctx *ctx, int vb_state)
>> +{
>> +       struct vb2_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) {
>>
>> +               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)
>> +{
>> +       struct gsc_ctx *ctx = priv;
>> +       int ret;
>> +
>> +       ret = gsc_m2m_ctx_stop_req(ctx);
>> +       if (ret == -ETIMEDOUT)
>> +               gsc_m2m_job_finish(ctx, VB2_BUF_STATE_ERROR);
>> +}
>> +
>> +int gsc_fill_addr(struct gsc_ctx *ctx)
>> +{
>> +       struct gsc_frame *s_frame, *d_frame;
>> +       struct vb2_buffer *vb = NULL;
>> +       int ret = 0;
>
>
> Unneeded initialization.
>
>> +
>> +       s_frame =&ctx->s_frame;
>> +       d_frame =&ctx->d_frame;
>>
>> +
>> +       vb = v4l2_m2m_next_src_buf(ctx->m2m_ctx);
>> +       ret = gsc_prepare_addr(ctx, vb, s_frame,&s_frame->addr);
>>
>> +       if (ret)
>> +               return ret;
>> +
>> +       vb = v4l2_m2m_next_dst_buf(ctx->m2m_ctx);
>> +       ret = gsc_prepare_addr(ctx, vb, d_frame,&d_frame->addr);
>> +
>> +       return ret;
>
>
> Just do:
>
>         return gsc_prepare_addr(ctx, vb, d_frame,&d_frame->addr);

I will do that.

>>
>> +}
>> +
<snip>
>> +int gsc_register_m2m_device(struct gsc_dev *gsc)
>> +{
>> +       struct video_device *vfd;
>> +       struct platform_device *pdev;
>> +       int ret = 0;
>> +
>> +       if (!gsc)
>> +               return -ENODEV;
>> +
>> +       pdev = gsc->pdev;
>> +
>> +       vfd = video_device_alloc();
>> +       if (!vfd) {
>> +               dev_err(&pdev->dev, "Failed to allocate video device\n");
>> +               return -ENOMEM;
>> +       }
>
>
> You could embed struct video_device into struct gsc_dev, rather than
> dynamically allocating it...

Yes. I can follow this.

>
>> +
>> +       vfd->fops       =&gsc_m2m_fops;
>> +       vfd->ioctl_ops  =&gsc_m2m_ioctl_ops;
>>
>> +       vfd->release    = video_device_release;
>
>
> ...and then change that to
>
>         vfd->release    = video_device_release_empty;
>

Ok. i will do that.

>> +       vfd->lock       =&gsc->lock;
>>
>> +       snprintf(vfd->name, sizeof(vfd->name), "%s.%d:m2m",
>> +                                       GSC_MODULE_NAME, gsc->id);
>> +
>> +       video_set_drvdata(vfd, gsc);
>> +
>> +       gsc->m2m.vfd = vfd;
>> +       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");
>> +               ret = PTR_ERR(gsc->m2m.m2m_dev);
>> +               goto err_m2m_r1;
>> +       }
>> +
>> +       ret = video_register_device(vfd, VFL_TYPE_GRABBER, -1);
>> +       if (ret) {
>> +               dev_err(&pdev->dev,
>> +                        "%s(): failed to register video device\n",
>> __func__);
>> +               goto err_m2m_r2;
>> +       }
>> +
>> +       pr_debug("gsc m2m driver registered as /dev/video%d", vfd->num);
>> +       return 0;
>> +
>> +err_m2m_r2:
>> +       v4l2_m2m_release(gsc->m2m.m2m_dev);
>> +err_m2m_r1:
>> +       video_device_release(gsc->m2m.vfd);
>> +
>> +       return ret;
>> +}
>> +
>> +void gsc_unregister_m2m_device(struct gsc_dev *gsc)
>> +{
>> +       if (gsc)
>> +               v4l2_m2m_release(gsc->m2m.m2m_dev);
>> +}
>
>
> Reviewed-by: Sylwester Nawrocki <[e-mail]>
>
> --
>
> Thanks,
> Sylwester

Regards,
Shaik Ameer Basha
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Patch

diff --git a/drivers/media/video/exynos-gsc/gsc-m2m.c b/drivers/media/video/exynos-gsc/gsc-m2m.c
new file mode 100644
index 0000000..3568d6f
--- /dev/null
+++ b/drivers/media/video/exynos-gsc/gsc-m2m.c
@@ -0,0 +1,781 @@ 
+/*
+ * 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/version.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 = 0;
+
+	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 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 int gsc_m2m_stop_streaming(struct vb2_queue *q)
+{
+	struct gsc_ctx *ctx = q->drv_priv;
+	int ret;
+
+	ret = gsc_m2m_ctx_stop_req(ctx);
+	if (ret == -ETIMEDOUT)
+		gsc_m2m_job_finish(ctx, VB2_BUF_STATE_ERROR);
+
+	pm_runtime_put(&ctx->gsc_dev->pdev->dev);
+
+	return 0;
+}
+
+void gsc_m2m_job_finish(struct gsc_ctx *ctx, int vb_state)
+{
+	struct vb2_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) {
+		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)
+{
+	struct gsc_ctx *ctx = priv;
+	int ret;
+
+	ret = gsc_m2m_ctx_stop_req(ctx);
+	if (ret == -ETIMEDOUT)
+		gsc_m2m_job_finish(ctx, VB2_BUF_STATE_ERROR);
+}
+
+int gsc_fill_addr(struct gsc_ctx *ctx)
+{
+	struct gsc_frame *s_frame, *d_frame;
+	struct vb2_buffer *vb = NULL;
+	int ret = 0;
+
+	s_frame = &ctx->s_frame;
+	d_frame = &ctx->d_frame;
+
+	vb = v4l2_m2m_next_src_buf(ctx->m2m_ctx);
+	ret = gsc_prepare_addr(ctx, vb, s_frame, &s_frame->addr);
+	if (ret)
+		return ret;
+
+	vb = v4l2_m2m_next_dst_buf(ctx->m2m_ctx);
+	ret = gsc_prepare_addr(ctx, vb, d_frame, &d_frame->addr);
+
+	return ret;
+}
+
+static void gsc_m2m_device_run(void *priv)
+{
+	struct gsc_ctx *ctx = priv;
+	struct gsc_dev *gsc;
+	unsigned long flags;
+	u32 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) ? 1 : 0;
+	ctx->state &= ~GSC_CTX_STOP_REQ;
+	if (is_set) {
+		wake_up(&gsc->irq_queue);
+		goto put_device;
+	}
+
+	ret = gsc_fill_addr(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,
+			const struct v4l2_format *fmt,
+			unsigned int *num_buffers, unsigned int *num_planes,
+			unsigned int sizes[], void *allocators[])
+{
+	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];
+		allocators[i] = ctx->gsc_dev->alloc_ctx;
+	}
+	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 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, vb);
+}
+
+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	 = gsc_unlock,
+	.wait_finish	 = gsc_lock,
+	.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->pdev->name, sizeof(cap->driver));
+	strlcpy(cap->card, gsc->pdev->name, sizeof(cap->card));
+	strlcpy(cap->bus_info, "platform", sizeof(cap->bus_info));
+	cap->device_caps = V4L2_CAP_STREAMING |
+				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;
+	struct gsc_frame *frame;
+	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;
+	} else if (reqbufs->count == 0) {
+		if (reqbufs->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)
+			gsc_ctx_state_lock_clear(GSC_SRC_FMT, ctx);
+		else
+			gsc_ctx_state_lock_clear(GSC_DST_FMT, ctx);
+	}
+
+	frame = ctx_get_frame(ctx, reqbufs->type);
+
+	return v4l2_m2m_reqbufs(file, ctx->m2m_ctx, reqbufs);
+}
+
+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_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;
+	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);
+
+	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;
+	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);
+
+	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);
+
+	if (mutex_lock_interruptible(&gsc->lock))
+		return -ERESTARTSYS;
+
+	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;
+	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 video_device *vfd;
+	struct platform_device *pdev;
+	int ret = 0;
+
+	if (!gsc)
+		return -ENODEV;
+
+	pdev = gsc->pdev;
+
+	vfd = video_device_alloc();
+	if (!vfd) {
+		dev_err(&pdev->dev, "Failed to allocate video device\n");
+		return -ENOMEM;
+	}
+
+	vfd->fops	= &gsc_m2m_fops;
+	vfd->ioctl_ops	= &gsc_m2m_ioctl_ops;
+	vfd->release	= video_device_release;
+	vfd->lock	= &gsc->lock;
+	snprintf(vfd->name, sizeof(vfd->name), "%s.%d:m2m",
+					GSC_MODULE_NAME, gsc->id);
+
+	video_set_drvdata(vfd, gsc);
+
+	gsc->m2m.vfd = vfd;
+	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");
+		ret = PTR_ERR(gsc->m2m.m2m_dev);
+		goto err_m2m_r1;
+	}
+
+	ret = video_register_device(vfd, VFL_TYPE_GRABBER, -1);
+	if (ret) {
+		dev_err(&pdev->dev,
+			 "%s(): failed to register video device\n", __func__);
+		goto err_m2m_r2;
+	}
+
+	pr_debug("gsc m2m driver registered as /dev/video%d", vfd->num);
+	return 0;
+
+err_m2m_r2:
+	v4l2_m2m_release(gsc->m2m.m2m_dev);
+err_m2m_r1:
+	video_device_release(gsc->m2m.vfd);
+
+	return ret;
+}
+
+void gsc_unregister_m2m_device(struct gsc_dev *gsc)
+{
+	if (gsc)
+		v4l2_m2m_release(gsc->m2m.m2m_dev);
+}