(Javier's opinion requested)
I'm no expert in i.MX27 hardware, would be great to have an ack from
someone, intensively working in this area. Javier, what do you think? Is
this really correct always for channel 1, or should this calculation
depend on the pixel format?
Thanks
Guennadi
On Sat, 16 Feb 2013, Christoph Fritz wrote:
> While using a mt9m001 (monochrome) camera the final output falsely gets
> horizontally divided into two pictures.
>
> The issue was git bisected to commit f410991dcf1f
>
> | [media] i.MX27 camera: add support for YUV420 format
> |
> | This patch uses channel 2 of the eMMa-PrP to convert
> | format provided by the sensor to YUV420.
> |
> | This format is very useful since it is used by the
> | internal H.264 encoder.
>
> It sets PICTURE_X_SIZE in register PRP_SRC_FRAME_SIZE to its full width
> while before that commit it was divided by two:
>
> - writel(((bytesperline >> 1) << 16) | icd->user_height,
> + writel((icd->user_width << 16) | icd->user_height,
> pcdev->base_emma + PRP_SRC_FRAME_SIZE);
>
> i.mx27 reference manual (41.6.12 PrP Source Frame Size Register) says:
>
> PICTURE_X_SIZE. These bits set the frame width to be
> processed in number of pixels. In YUV 4:2:0 mode, Cb and
> Cr widths are taken as PICTURE_X_SIZE/2 pixels. In YUV
> 4:2:0 mode, this value should be a multiple of 8-pixels.
> In other modes (RGB, YUV 4:2:2 and YUV 4:4:4) it should
> be a multiple of 4 pixels.
>
> This patch reverts to PICTURE_X_SIZE/2 for channel 1.
>
> Tested on Kernel 3.4, merged to 3.8rc.
>
> Signed-off-by: Christoph Fritz <chf.fritz@xxxxxxxxxxxxxx>
> ---
> drivers/media/platform/soc_camera/mx2_camera.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/media/platform/soc_camera/mx2_camera.c b/drivers/media/platform/soc_camera/mx2_camera.c
> index 8bda2c9..795bd3f 100644
> --- a/drivers/media/platform/soc_camera/mx2_camera.c
> +++ b/drivers/media/platform/soc_camera/mx2_camera.c
> @@ -778,11 +778,11 @@ static void mx27_camera_emma_buf_init(struct soc_camera_device *icd,
> struct mx2_camera_dev *pcdev = ici->priv;
> struct mx2_fmt_cfg *prp = pcdev->emma_prp;
>
> - writel((pcdev->s_width << 16) | pcdev->s_height,
> - pcdev->base_emma + PRP_SRC_FRAME_SIZE);
> writel(prp->cfg.src_pixel,
> pcdev->base_emma + PRP_SRC_PIXEL_FORMAT_CNTL);
> if (prp->cfg.channel == 1) {
> + writel(((bytesperline >> 1) << 16) | pcdev->s_height,
> + pcdev->base_emma + PRP_SRC_FRAME_SIZE);
> writel((icd->user_width << 16) | icd->user_height,
> pcdev->base_emma + PRP_CH1_OUT_IMAGE_SIZE);
> writel(bytesperline,
> @@ -790,6 +790,8 @@ static void mx27_camera_emma_buf_init(struct soc_camera_device *icd,
> writel(prp->cfg.ch1_pixel,
> pcdev->base_emma + PRP_CH1_PIXEL_FORMAT_CNTL);
> } else { /* channel 2 */
> + writel((pcdev->s_width << 16) | pcdev->s_height,
> + pcdev->base_emma + PRP_SRC_FRAME_SIZE);
> writel((icd->user_width << 16) | icd->user_height,
> pcdev->base_emma + PRP_CH2_OUT_IMAGE_SIZE);
> }
> --
> 1.7.10.4
>
>
>
---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
