[PATCH 2/4] V4L: mx3_camera: convert to videobuf2

Marek Szyprowski m.szyprowski at samsung.com
Mon Feb 21 03:05:32 EST 2011


Hello,

On Friday, February 18, 2011 9:14 AM Guennadi Liakhovetski wrote:

> Now that soc-camera supports videobuf API v1 and v2, camera-host drivers
> can be converted to videobuf2 individually. This patch converts the
> mx3_camera driver.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski at gmx.de>
> ---
> 
> This one is also on git.linuxtv.org already.
> 
>  drivers/media/video/mx3_camera.c |  342 ++++++++++++++++----------------------
>  1 files changed, 143 insertions(+), 199 deletions(-)
> 
> diff --git a/drivers/media/video/mx3_camera.c b/drivers/media/video/mx3_camera.c
> index b9cb4a4..d61ff0d 100644
> --- a/drivers/media/video/mx3_camera.c
> +++ b/drivers/media/video/mx3_camera.c
> @@ -21,7 +21,7 @@
> 
>  #include <media/v4l2-common.h>
>  #include <media/v4l2-dev.h>
> -#include <media/videobuf-dma-contig.h>
> +#include <media/videobuf2-dma-contig.h>
>  #include <media/soc_camera.h>
>  #include <media/soc_mediabus.h>
> 
> @@ -62,10 +62,16 @@
> 
>  #define MAX_VIDEO_MEM 16
> 
> +enum csi_buffer_state {
> +	CSI_BUF_NEEDS_INIT,
> +	CSI_BUF_PREPARED,
> +};
> +
>  struct mx3_camera_buffer {
>  	/* common v4l buffer stuff -- must be first */
> -	struct videobuf_buffer			vb;
> -	enum v4l2_mbus_pixelcode		code;
> +	struct vb2_buffer			vb;
> +	enum csi_buffer_state			state;
> +	struct list_head			queue;
> 
>  	/* One descriptot per scatterlist (per frame) */
>  	struct dma_async_tx_descriptor		*txd;
> @@ -108,6 +114,9 @@ struct mx3_camera_dev {
>  	struct list_head	capture;
>  	spinlock_t		lock;		/* Protects video buffer lists */
>  	struct mx3_camera_buffer *active;
> +	struct vb2_alloc_ctx	*alloc_ctx;
> +	enum v4l2_field		field;
> +	int			sequence;
> 
>  	/* IDMAC / dmaengine interface */
>  	struct idmac_channel	*idmac_channel[1];	/* We need one channel */
> @@ -130,6 +139,11 @@ static void csi_reg_write(struct mx3_camera_dev *mx3, u32 value, off_t reg)
>  	__raw_writel(value, mx3->base + reg);
>  }
> 
> +static struct mx3_camera_buffer *to_mx3_vb(struct vb2_buffer *vb)
> +{
> +	return container_of(vb, struct mx3_camera_buffer, vb);
> +}
> +
>  /* Called from the IPU IDMAC ISR */
>  static void mx3_cam_dma_done(void *arg)
>  {
> @@ -137,20 +151,20 @@ static void mx3_cam_dma_done(void *arg)
>  	struct dma_chan *chan = desc->txd.chan;
>  	struct idmac_channel *ichannel = to_idmac_chan(chan);
>  	struct mx3_camera_dev *mx3_cam = ichannel->client;
> -	struct videobuf_buffer *vb;
> 
>  	dev_dbg(chan->device->dev, "callback cookie %d, active DMA 0x%08x\n",
>  		desc->txd.cookie, mx3_cam->active ? sg_dma_address(&mx3_cam->active->sg) : 0);
> 
>  	spin_lock(&mx3_cam->lock);
>  	if (mx3_cam->active) {
> -		vb = &mx3_cam->active->vb;
> -
> -		list_del_init(&vb->queue);
> -		vb->state = VIDEOBUF_DONE;
> -		do_gettimeofday(&vb->ts);
> -		vb->field_count++;
> -		wake_up(&vb->done);
> +		struct vb2_buffer *vb = &mx3_cam->active->vb;
> +		struct mx3_camera_buffer *buf = to_mx3_vb(vb);
> +
> +		list_del_init(&buf->queue);
> +		do_gettimeofday(&vb->v4l2_buf.timestamp);
> +		vb->v4l2_buf.field = mx3_cam->field;
> +		vb->v4l2_buf.sequence = mx3_cam->sequence++;
> +		vb2_buffer_done(vb, VB2_BUF_STATE_DONE);
>  	}
> 
>  	if (list_empty(&mx3_cam->capture)) {
> @@ -165,38 +179,10 @@ static void mx3_cam_dma_done(void *arg)
>  	}
> 
>  	mx3_cam->active = list_entry(mx3_cam->capture.next,
> -				     struct mx3_camera_buffer, vb.queue);
> -	mx3_cam->active->vb.state = VIDEOBUF_ACTIVE;
> +				     struct mx3_camera_buffer, queue);
>  	spin_unlock(&mx3_cam->lock);
>  }
> 
> -static void free_buffer(struct videobuf_queue *vq, struct mx3_camera_buffer *buf)
> -{
> -	struct soc_camera_device *icd = vq->priv_data;
> -	struct videobuf_buffer *vb = &buf->vb;
> -	struct dma_async_tx_descriptor *txd = buf->txd;
> -	struct idmac_channel *ichan;
> -
> -	BUG_ON(in_interrupt());
> -
> -	dev_dbg(icd->dev.parent, "%s (vb=0x%p) 0x%08lx %d\n", __func__,
> -		vb, vb->baddr, vb->bsize);
> -
> -	/*
> -	 * This waits until this buffer is out of danger, i.e., until it is no
> -	 * longer in STATE_QUEUED or STATE_ACTIVE
> -	 */
> -	videobuf_waiton(vq, vb, 0, 0);
> -	if (txd) {
> -		ichan = to_idmac_chan(txd->chan);
> -		async_tx_ack(txd);
> -	}
> -	videobuf_dma_contig_free(vq, vb);
> -	buf->txd = NULL;
> -
> -	vb->state = VIDEOBUF_NEEDS_INIT;
> -}
> -
>  /*
>   * Videobuf operations
>   */
> @@ -205,10 +191,11 @@ static void free_buffer(struct videobuf_queue *vq, struct mx3_camera_buffer *buf
>   * Calculate the __buffer__ (not data) size and number of buffers.
>   * Called with .vb_lock held
>   */
> -static int mx3_videobuf_setup(struct videobuf_queue *vq, unsigned int *count,
> -			      unsigned int *size)
> +static int mx3_videobuf_setup(struct vb2_queue *vq,
> +			unsigned int *count, unsigned int *num_planes,
> +			unsigned long sizes[], void *alloc_ctxs[])
>  {
> -	struct soc_camera_device *icd = vq->priv_data;
> +	struct soc_camera_device *icd = soc_camera_from_vb2q(vq);
>  	struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
>  	struct mx3_camera_dev *mx3_cam = ici->priv;
>  	int bytes_per_line = soc_mbus_bytes_per_line(icd->user_width,
> @@ -220,104 +207,68 @@ static int mx3_videobuf_setup(struct videobuf_queue *vq, unsigned int *count,
>  	if (!mx3_cam->idmac_channel[0])
>  		return -EINVAL;
> 
> -	*size = bytes_per_line * icd->user_height;
> +	*num_planes = 1;
> +
> +	mx3_cam->sequence = 0;
> +	sizes[0] = bytes_per_line * icd->user_height;
> +	alloc_ctxs[0] = mx3_cam->alloc_ctx;
> 
>  	if (!*count)
>  		*count = 32;
> 
> -	if (*size * *count > MAX_VIDEO_MEM * 1024 * 1024)
> -		*count = MAX_VIDEO_MEM * 1024 * 1024 / *size;
> +	if (sizes[0] * *count > MAX_VIDEO_MEM * 1024 * 1024)
> +		*count = MAX_VIDEO_MEM * 1024 * 1024 / sizes[0];
> 
>  	return 0;
>  }
> 
>  /* Called with .vb_lock held */

vb_lock has no meaning in vb2, so the above line should be removed imho.

> -static int mx3_videobuf_prepare(struct videobuf_queue *vq,
> -		struct videobuf_buffer *vb, enum v4l2_field field)
> +static int mx3_videobuf_prepare(struct vb2_buffer *vb)
>  {
> -	struct soc_camera_device *icd = vq->priv_data;
> +	struct soc_camera_device *icd = soc_camera_from_vb2q(vb->vb2_queue);
>  	struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
>  	struct mx3_camera_dev *mx3_cam = ici->priv;
> -	struct mx3_camera_buffer *buf =
> -		container_of(vb, struct mx3_camera_buffer, vb);
> +	struct idmac_channel *ichan = mx3_cam->idmac_channel[0];
> +	struct scatterlist *sg;
> +	struct mx3_camera_buffer *buf;
>  	size_t new_size;
> -	int ret;
>  	int bytes_per_line = soc_mbus_bytes_per_line(icd->user_width,
>  						icd->current_fmt->host_fmt);
> 
>  	if (bytes_per_line < 0)
>  		return bytes_per_line;
> 
> -	new_size = bytes_per_line * icd->user_height;
> +	buf = to_mx3_vb(vb);
> +	sg = &buf->sg;
> 
> -	/*
> -	 * I think, in buf_prepare you only have to protect global data,
> -	 * the actual buffer is yours
> -	 */
> -
> -	if (buf->code	!= icd->current_fmt->code ||
> -	    vb->width	!= icd->user_width ||
> -	    vb->height	!= icd->user_height ||
> -	    vb->field	!= field) {
> -		buf->code	= icd->current_fmt->code;
> -		vb->width	= icd->user_width;
> -		vb->height	= icd->user_height;
> -		vb->field	= field;
> -		if (vb->state != VIDEOBUF_NEEDS_INIT)
> -			free_buffer(vq, buf);
> -	}
> +	new_size = bytes_per_line * icd->user_height;
> 
> -	if (vb->baddr && vb->bsize < new_size) {
> -		/* User provided buffer, but it is too small */
> -		ret = -ENOMEM;
> -		goto out;
> +	if (vb2_plane_size(vb, 0) < new_size) {
> +		dev_err(icd->dev.parent, "Buffer too small (%lu < %zu)\n",
> +			vb2_plane_size(vb, 0), new_size);
> +		return -ENOBUFS;
>  	}
> 
> -	if (vb->state == VIDEOBUF_NEEDS_INIT) {
> -		struct idmac_channel *ichan = mx3_cam->idmac_channel[0];
> -		struct scatterlist *sg = &buf->sg;
> -
> -		/*
> -		 * The total size of video-buffers that will be allocated / mapped.
> -		 * *size that we calculated in videobuf_setup gets assigned to
> -		 * vb->bsize, and now we use the same calculation to get vb->size.
> -		 */
> -		vb->size = new_size;
> -
> -		/* This actually (allocates and) maps buffers */
> -		ret = videobuf_iolock(vq, vb, NULL);
> -		if (ret)
> -			goto fail;
> -
> -		/*
> -		 * We will have to configure the IDMAC channel. It has two slots
> -		 * for DMA buffers, we shall enter the first two buffers there,
> -		 * and then submit new buffers in DMA-ready interrupts
> -		 */
> -		sg_init_table(sg, 1);
> -		sg_dma_address(sg)	= videobuf_to_dma_contig(vb);
> -		sg_dma_len(sg)		= vb->size;
> +	if (buf->state == CSI_BUF_NEEDS_INIT) {
> +		sg_dma_address(sg)	= (dma_addr_t)icd->vb2_vidq.mem_ops->cookie(
> +			vb->planes[0].mem_priv);

You should use vb2_dma_contig_plane_paddr() function from include/media/videobuf2-dma-contig.h
instead of hacking with cookie directly:
	sg_dma_address(sg) = vb2_dma_contig_plane_paddr(vb, 0);

Everything else look fine!

> [snip]

Best regards
--
Marek Szyprowski
Samsung Poland R&D Center





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