Re: [PATCHv2 1/8] v4l2-subdev: replace v4l2_subdev_fh by v4l2_subdev_pad_config

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Hans,

Thank you for the patch.

On Wednesday 04 March 2015 10:47:54 Hans Verkuil wrote:
> From: Hans Verkuil <hans.verkuil@cisco.com>
> 
> If a subdevice pad op is called from a bridge driver, then there is
> no v4l2_subdev_fh struct that can be passed to the subdevice. This
> made it hard to use such subdevs from a bridge driver.
> 
> This patch replaces the v4l2_subdev_fh pointer by a v4l2_subdev_pad_config
> pointer in the pad ops. This allows bridge drivers to use the various
> try_ pad ops by creating a v4l2_subdev_pad_config struct and passing it
> along to the pad op.
> 
> The v4l2_subdev_get_try_* macros had to be changed because of this, so
> I also took the opportunity to use the full name of the
> v4l2_subdev_get_try_* functions in the __V4L2_SUBDEV_MK_GET_TRY macro
> arguments: if you now do 'git grep v4l2_subdev_get_try_format' you will
> actually find the header where it is defined.
> 
> One remark regarding the drivers/staging/media/davinci_vpfe patches: the
> *_init_formats() functions assumed that fh could be NULL. However, that's
> not true for this driver, it's always set. This is almost certainly a copy
> and paste from the omap3isp driver. I've updated the code to reflect the
> fact that fh is never NULL.
> 
> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
> Acked-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
> Tested-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>

[snip]

> diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
> index 5beeb87..0c43546 100644
> --- a/include/media/v4l2-subdev.h
> +++ b/include/media/v4l2-subdev.h
> @@ -482,6 +482,18 @@ struct v4l2_subdev_ir_ops {
>  				struct v4l2_subdev_ir_parameters *params);
>  };
> 
> +/*
> + * Used for storing subdev pad information. This structure only needs
> + * to be passed to the pad op if the 'which' field of the main argument
> + * is set to V4L2_SUBDEV_FORMAT_TRY. For V4L2_SUBDEV_FORMAT_ACTIVE just
> + * pass NULL.

Nitpicking, I would say "For V4L2_SUBDEV_FORMAT_ACTIVE is it safe to pass 
NULL.", otherwise it could be understood that callers have to pass NULL for 
ACTIVE.

> + */
> +struct v4l2_subdev_pad_config {
> +	struct v4l2_mbus_framefmt try_fmt;
> +	struct v4l2_rect try_crop;
> +	struct v4l2_rect try_compose;
> +};

-- 
Regards,

Laurent Pinchart