Re: [PATCH v2 3/3] media: atmel-isi: add sanity check for supported formats in set_fmt()

From: Laurent Pinchart
Date: Thu Aug 20 2015 - 14:30:12 EST


Hi Josh,

Thank you for the patch.

On Wednesday 05 August 2015 11:26:29 Josh Wu wrote:
> After adding the format check in set_fmt(), we don't need any format check
> in configure_geometry(). So make configure_geometry() as void type.
>
> Signed-off-by: Josh Wu <josh.wu@xxxxxxxxx>
> ---
>
> Changes in v2:
> - new added patch
>
> drivers/media/platform/soc_camera/atmel-isi.c | 39 ++++++++++++++++++------
> 1 file changed, 31 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/media/platform/soc_camera/atmel-isi.c
> b/drivers/media/platform/soc_camera/atmel-isi.c index cb46aec..d0df518
> 100644
> --- a/drivers/media/platform/soc_camera/atmel-isi.c
> +++ b/drivers/media/platform/soc_camera/atmel-isi.c
> @@ -103,17 +103,19 @@ static u32 isi_readl(struct atmel_isi *isi, u32 reg)
> return readl(isi->regs + reg);
> }
>
> -static int configure_geometry(struct atmel_isi *isi, u32 width,
> +static void configure_geometry(struct atmel_isi *isi, u32 width,
> u32 height, u32 code)
> {
> u32 cfg2;
>
> /* According to sensor's output format to set cfg2 */
> switch (code) {
> - /* YUV, including grey */
> + default:
> + /* Grey */
> case MEDIA_BUS_FMT_Y8_1X8:
> cfg2 = ISI_CFG2_GRAYSCALE;
> break;
> + /* YUV */
> case MEDIA_BUS_FMT_VYUY8_2X8:
> cfg2 = ISI_CFG2_YCC_SWAP_MODE_3;
> break;
> @@ -127,8 +129,6 @@ static int configure_geometry(struct atmel_isi *isi, u32
> width, cfg2 = ISI_CFG2_YCC_SWAP_DEFAULT;
> break;
> /* RGB, TODO */
> - default:
> - return -EINVAL;
> }
>
> isi_writel(isi, ISI_CTRL, ISI_CTRL_DIS);
> @@ -139,8 +139,29 @@ static int configure_geometry(struct atmel_isi *isi,
> u32 width, cfg2 |= ((height - 1) << ISI_CFG2_IM_VSIZE_OFFSET)
> & ISI_CFG2_IM_VSIZE_MASK;
> isi_writel(isi, ISI_CFG2, cfg2);
> +}
>
> - return 0;
> +static bool is_supported(struct soc_camera_device *icd,
> + const struct soc_camera_format_xlate *xlate)
> +{
> + bool ret = true;
> +
> + switch (xlate->code) {
> + /* YUV, including grey */
> + case MEDIA_BUS_FMT_Y8_1X8:
> + case MEDIA_BUS_FMT_VYUY8_2X8:
> + case MEDIA_BUS_FMT_UYVY8_2X8:
> + case MEDIA_BUS_FMT_YVYU8_2X8:
> + case MEDIA_BUS_FMT_YUYV8_2X8:

I would just return true here and false below, and remove the ret variable.

> + break;
> + /* RGB, TODO */
> + default:
> + dev_err(icd->parent, "not supported format: %d\n",
> + xlate->code);

If this can happen when userspace asks for an unsupported format I don't think
you should print an error message to the kernel log.

> + ret = false;
> + }
> +
> + return ret;
> }
>
> static irqreturn_t atmel_isi_handle_streaming(struct atmel_isi *isi)
> @@ -391,10 +412,8 @@ static int start_streaming(struct vb2_queue *vq,
> unsigned int count) /* Disable all interrupts */
> isi_writel(isi, ISI_INTDIS, (u32)~0UL);
>
> - ret = configure_geometry(isi, icd->user_width, icd->user_height,
> + configure_geometry(isi, icd->user_width, icd->user_height,
> icd->current_fmt->code);
> - if (ret < 0)
> - return ret;
>
> spin_lock_irq(&isi->lock);
> /* Clear any pending interrupt */
> @@ -515,6 +534,10 @@ static int isi_camera_set_fmt(struct soc_camera_device
> *icd, if (mf->code != xlate->code)
> return -EINVAL;
>
> + /* check with atmel-isi support format */
> + if (!is_supported(icd, xlate))
> + return -EINVAL;
> +

S_FMT is supposed to pick a suitable default format when the requested format
isn't supported. It shouldn't return an error.

> pix->width = mf->width;
> pix->height = mf->height;
> pix->field = mf->field;

--
Regards,

Laurent Pinchart

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