Re: [PATCH 2/6] media: imx: Unstage the imx7-media-csi driver

[paul.elder@ideasonboard.com]

On Wed, Sep 07, 2022 at 11:04:20PM +0300, Laurent Pinchart wrote:
> The imx7-media-csi driver, currently in staging, is ready for
> prime-time. The staging TODO file lists a few items specific to that
> driver, that are already addressed (the "all of the above" part) or can
> be addressed later:
> 
> - The frame interval monitoring support is a software mechanism to
>   monitor the device for unexpected stalls, and should be part of the
>   V4L2 core if desired.
> 
> - Restricting the support media bus formats based on the SoC integration
>   only aims at reducing userspace confusion by not enumerating options
>   that are known not to be possible, it won't cause regressions if
>   handled later.
> 
> Move the description of the media bus format restriction TODO item to
> the driver, drop the other TODO items, and move the driver out of
> staging.
> 
> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>

> ---
>  MAINTAINERS                                   |  2 +-
>  drivers/media/platform/nxp/Kconfig            | 13 +++++++++
>  drivers/media/platform/nxp/Makefile           |  1 +
>  .../platform/nxp}/imx7-media-csi.c            | 24 +++++++++++++++
>  drivers/staging/media/imx/Kconfig             |  7 -----
>  drivers/staging/media/imx/Makefile            |  1 -
>  drivers/staging/media/imx/TODO                | 29 -------------------
>  7 files changed, 39 insertions(+), 38 deletions(-)
>  rename drivers/{staging/media/imx => media/platform/nxp}/imx7-media-csi.c (97%)
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 338c155f60ef..1dfa1d51955c 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -12595,7 +12595,7 @@ F:	Documentation/admin-guide/media/imx7.rst
>  F:	Documentation/devicetree/bindings/media/nxp,imx-mipi-csi2.yaml
>  F:	Documentation/devicetree/bindings/media/nxp,imx7-csi.yaml
>  F:	drivers/media/platform/nxp/imx-mipi-csis.c
> -F:	drivers/staging/media/imx/imx7-media-csi.c
> +F:	drivers/media/platform/nxp/imx7-media-csi.c
>  
>  MEDIA DRIVERS FOR HELENE
>  M:	Abylay Ospan <aospan@netup.ru>
> diff --git a/drivers/media/platform/nxp/Kconfig b/drivers/media/platform/nxp/Kconfig
> index 1ac0a6e91111..3aa4207bcd41 100644
> --- a/drivers/media/platform/nxp/Kconfig
> +++ b/drivers/media/platform/nxp/Kconfig
> @@ -4,6 +4,19 @@
>  
>  comment "NXP media platform drivers"
>  
> +config VIDEO_IMX7_CSI
> +	tristate "NXP CSI Bridge driver"
> +	depends on ARCH_MXC || COMPILE_TEST
> +	depends on HAS_DMA
> +	depends on VIDEO_DEV
> +	select MEDIA_CONTROLLER
> +	select V4L2_FWNODE
> +	select VIDEOBUF2_DMA_CONTIG
> +	select VIDEO_V4L2_SUBDEV_API
> +	help
> +	  Driver for the NXP Camera Sensor Interface (CSI) Bridge. This device
> +	  is found in the i.MX6UL/L, i.MX7 and i.MX8M[MQ] SoCs.
> +
>  config VIDEO_IMX_MIPI_CSIS
>  	tristate "NXP MIPI CSI-2 CSIS receiver found on i.MX7 and i.MX8 models"
>  	depends on ARCH_MXC || COMPILE_TEST
> diff --git a/drivers/media/platform/nxp/Makefile b/drivers/media/platform/nxp/Makefile
> index efc38c6578ce..92cb8f4c215e 100644
> --- a/drivers/media/platform/nxp/Makefile
> +++ b/drivers/media/platform/nxp/Makefile
> @@ -2,6 +2,7 @@
>  
>  obj-y += imx-jpeg/
>  
> +obj-$(CONFIG_VIDEO_IMX7_CSI) += imx7-media-csi.o
>  obj-$(CONFIG_VIDEO_IMX_MIPI_CSIS) += imx-mipi-csis.o
>  obj-$(CONFIG_VIDEO_IMX_PXP) += imx-pxp.o
>  obj-$(CONFIG_VIDEO_MX2_EMMAPRP) += mx2_emmaprp.o
> diff --git a/drivers/staging/media/imx/imx7-media-csi.c b/drivers/media/platform/nxp/imx7-media-csi.c
> similarity index 97%
> rename from drivers/staging/media/imx/imx7-media-csi.c
> rename to drivers/media/platform/nxp/imx7-media-csi.c
> index 21d6e56ffcd4..72de9fc9862a 100644
> --- a/drivers/staging/media/imx/imx7-media-csi.c
> +++ b/drivers/media/platform/nxp/imx7-media-csi.c
> @@ -807,6 +807,30 @@ static irqreturn_t imx7_csi_irq_handler(int irq, void *data)
>   * List of supported pixel formats for the subdevs. Keep V4L2_PIX_FMT_UYVY and
>   * MEDIA_BUS_FMT_UYVY8_2X8 first to match IMX7_CSI_DEF_PIX_FORMAT and
>   * IMX7_CSI_DEF_MBUS_CODE.
> + *
> + * TODO: Restrict the supported formats list based on the SoC integration.
> + *
> + * The CSI bridge can be configured to sample pixel components from the Rx queue
> + * in single (8bpp) or double (16bpp) component modes. Image format variants
> + * with different sample sizes (ie YUYV_2X8 vs YUYV_1X16) determine the pixel
> + * components sampling size per each clock cycle and their packing mode (see
> + * imx7_csi_configure() for details).
> + *
> + * As the CSI bridge can be interfaced with different IP blocks depending on the
> + * SoC model it is integrated on, the Rx queue sampling size should match the
> + * size of the samples transferred by the transmitting IP block. To avoid
> + * misconfigurations of the capture pipeline, the enumeration of the supported
> + * formats should be restricted to match the pixel source transmitting mode.
> + *
> + * Example: i.MX8MM SoC integrates the CSI bridge with the Samsung CSIS CSI-2
> + * receiver which operates in dual pixel sampling mode. The CSI bridge should
> + * only expose the 1X16 formats variant which instructs it to operate in dual
> + * pixel sampling mode. When the CSI bridge is instead integrated on an i.MX7,
> + * which supports both serial and parallel input, it should expose both
> + * variants.
> + *
> + * This currently only applies to YUYV formats, but other formats might need to
> + * be handled in the same way.
>   */
>  static const struct imx7_csi_pixfmt pixel_formats[] = {
>  	/*** YUV formats start here ***/
> diff --git a/drivers/staging/media/imx/Kconfig b/drivers/staging/media/imx/Kconfig
> index bfb849701489..21fd79515042 100644
> --- a/drivers/staging/media/imx/Kconfig
> +++ b/drivers/staging/media/imx/Kconfig
> @@ -23,13 +23,6 @@ config VIDEO_IMX_CSI
>  	default y
>  	help
>  	  A video4linux camera sensor interface driver for i.MX5/6.
> -
> -config VIDEO_IMX7_CSI
> -	tristate "i.MX6UL/L / i.MX7 / i.MX8M Camera Sensor Interface driver"
> -	default y
> -	help
> -	  Enable support for video4linux camera sensor interface driver for
> -	  i.MX6UL/L, i.MX7 or i.MX8M.
>  endmenu
>  endif
>  
> diff --git a/drivers/staging/media/imx/Makefile b/drivers/staging/media/imx/Makefile
> index cef9f30eb401..906a422aa656 100644
> --- a/drivers/staging/media/imx/Makefile
> +++ b/drivers/staging/media/imx/Makefile
> @@ -14,5 +14,4 @@ obj-$(CONFIG_VIDEO_IMX_CSI) += imx6-media.o
>  obj-$(CONFIG_VIDEO_IMX_CSI) += imx6-media-csi.o
>  obj-$(CONFIG_VIDEO_IMX_CSI) += imx6-mipi-csi2.o
>  
> -obj-$(CONFIG_VIDEO_IMX7_CSI) += imx7-media-csi.o
>  obj-$(CONFIG_VIDEO_IMX8MQ_MIPI_CSI2) += imx8mq-mipi-csi2.o
> diff --git a/drivers/staging/media/imx/TODO b/drivers/staging/media/imx/TODO
> index 5d3a337c8702..afee26870af7 100644
> --- a/drivers/staging/media/imx/TODO
> +++ b/drivers/staging/media/imx/TODO
> @@ -23,32 +23,3 @@
>  - Similarly to the legacy control handling, legacy format handling where
>    formats on the video nodes are influenced by the active format of the
>    connected subdev should be removed.
> -
> -- i.MX7: all of the above, since it uses the imx media core
> -
> -- i.MX7: use Frame Interval Monitor
> -
> -- imx7-media-csi: Restrict the supported formats list to the SoC version.
> -
> -  The imx7 CSI bridge can be configured to sample pixel components from the Rx
> -  queue in single (8bpp) or double (16bpp) component modes. Image format
> -  variants with different sample sizes (ie YUYV_2X8 vs YUYV_1X16) determine the
> -  pixel components sampling size per each clock cycle and their packing mode
> -  (see imx7_csi_configure() for details).
> -
> -  As the imx7 CSI bridge can be interfaced with different IP blocks depending on
> -  the SoC model it is integrated on, the Rx queue sampling size should match
> -  the size of the samples transferred by the transmitting IP block.
> -
> -  To avoid mis-configurations of the capture pipeline, the enumeration of the
> -  supported formats should be restricted to match the pixel source transmitting
> -  mode.
> -
> -  Example: i.MX8MM SoC integrates the CSI bridge with the Samsung CSIS CSI-2
> -  receiver which operates in dual pixel sampling mode. The CSI bridge should
> -  only expose the 1X16 formats variant which instructs it to operate in dual
> -  pixel sampling mode. When the CSI bridge is instead integrated on an i.MX7,
> -  which supports both serial and parallel input, it should expose both variants.
> -
> -  This currently only applies to YUYV formats, but other formats might need
> -  to be handled in the same way.