Re: [PATCH v3 2/2] media: mtk-vcodec: fix build breakage when one of VPU or SCP is enabled

[Randy Dunlap]

On 10/11/20 10:35 PM, Alexandre Courbot wrote:
> The addition of MT8183 support added a dependency on the SCP remoteproc
> module. However the initial patch used the "select" Kconfig directive,
> which may result in the SCP module to not be compiled if remoteproc was
> disabled. In such a case, mtk-vcodec would try to link against
> non-existent SCP symbols. "select" was clearly misused here as explained
> in kconfig-language.txt.
> 
> Replace this by a "depends" directive on at least one of the VPU and
> SCP modules, to allow the driver to be compiled as long as one of these
> is enabled, and adapt the code to support this new scenario.
> 
> Also adapt the Kconfig text to explain the extra requirements for MT8173
> and MT8183.
> 
> Reported-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxxxx>
> Acked-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> # build-tested

That Ack applied to v2. I have not tested nor acked this version of the patch.

> Acked-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> ---
>  drivers/media/platform/Kconfig                | 22 +++++++++++++++----
>  drivers/media/platform/mtk-vcodec/Makefile    | 10 +++++++--
>  .../platform/mtk-vcodec/mtk_vcodec_fw_priv.h  | 18 +++++++++++++++
>  3 files changed, 44 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> index a3cb104956d5..457b6c39ddc0 100644
> --- a/drivers/media/platform/Kconfig
> +++ b/drivers/media/platform/Kconfig
> @@ -253,18 +253,32 @@ config VIDEO_MEDIATEK_VCODEC
>  	depends on MTK_IOMMU || COMPILE_TEST
>  	depends on VIDEO_DEV && VIDEO_V4L2
>  	depends on ARCH_MEDIATEK || COMPILE_TEST
> +	depends on VIDEO_MEDIATEK_VPU || MTK_SCP
> +	# The two following lines ensure we have the same state ("m" or "y") as
> +	# our dependencies, to avoid missing symbols during link.
> +	depends on VIDEO_MEDIATEK_VPU || !VIDEO_MEDIATEK_VPU
> +	depends on MTK_SCP || !MTK_SCP
>  	select VIDEOBUF2_DMA_CONTIG
>  	select V4L2_MEM2MEM_DEV
> -	select VIDEO_MEDIATEK_VPU
> -	select MTK_SCP
> +	select VIDEO_MEDIATEK_VCODEC_VPU if VIDEO_MEDIATEK_VPU
> +	select VIDEO_MEDIATEK_VCODEC_SCP if MTK_SCP
>  	help
>  	    Mediatek video codec driver provides HW capability to
> -	    encode and decode in a range of video formats
> -	    This driver rely on VPU driver to communicate with VPU.
> +	    encode and decode in a range of video formats on MT8173
> +	    and MT8183.
> +
> +	    Note that support for MT8173 requires VIDEO_MEDIATEK_VPU to
> +	    also be selected. Support for MT8183 depends on MTK_SCP.
>  
>  	    To compile this driver as modules, choose M here: the
>  	    modules will be called mtk-vcodec-dec and mtk-vcodec-enc.
>  
> +config VIDEO_MEDIATEK_VCODEC_VPU
> +	bool
> +
> +config VIDEO_MEDIATEK_VCODEC_SCP
> +	bool
> +
>  config VIDEO_MEM2MEM_DEINTERLACE
>  	tristate "Deinterlace support"
>  	depends on VIDEO_DEV && VIDEO_V4L2
> diff --git a/drivers/media/platform/mtk-vcodec/Makefile b/drivers/media/platform/mtk-vcodec/Makefile
> index 6e1ea3a9f052..4618d43dbbc8 100644
> --- a/drivers/media/platform/mtk-vcodec/Makefile
> +++ b/drivers/media/platform/mtk-vcodec/Makefile
> @@ -25,5 +25,11 @@ mtk-vcodec-enc-y := venc/venc_vp8_if.o \
>  mtk-vcodec-common-y := mtk_vcodec_intr.o \
>  		mtk_vcodec_util.o \
>  		mtk_vcodec_fw.o \
> -		mtk_vcodec_fw_vpu.o \
> -		mtk_vcodec_fw_scp.o
> +
> +ifneq ($(CONFIG_VIDEO_MEDIATEK_VCODEC_VPU),)
> +mtk-vcodec-common-y += mtk_vcodec_fw_vpu.o
> +endif
> +
> +ifneq ($(CONFIG_VIDEO_MEDIATEK_VCODEC_SCP),)
> +mtk-vcodec-common-y += mtk_vcodec_fw_scp.o
> +endif
> diff --git a/drivers/media/platform/mtk-vcodec/mtk_vcodec_fw_priv.h b/drivers/media/platform/mtk-vcodec/mtk_vcodec_fw_priv.h
> index 51f1694a7c7d..b41e66185cec 100644
> --- a/drivers/media/platform/mtk-vcodec/mtk_vcodec_fw_priv.h
> +++ b/drivers/media/platform/mtk-vcodec/mtk_vcodec_fw_priv.h
> @@ -27,8 +27,26 @@ struct mtk_vcodec_fw_ops {
>  	void (*release)(struct mtk_vcodec_fw *fw);
>  };
>  
> +#if IS_ENABLED(CONFIG_VIDEO_MEDIATEK_VCODEC_VPU)
>  struct mtk_vcodec_fw *mtk_vcodec_fw_vpu_init(struct mtk_vcodec_dev *dev,
>  					     enum mtk_vcodec_fw_use fw_use);
> +#else
> +static inline struct mtk_vcodec_fw *
> +mtk_vcodec_fw_vpu_init(struct mtk_vcodec_dev *dev,
> +		       enum mtk_vcodec_fw_use fw_use)
> +{
> +	return ERR_PTR(-ENODEV);
> +}
> +#endif /* CONFIG_VIDEO_MEDIATEK_VCODEC_VPU */
> +
> +#if IS_ENABLED(CONFIG_VIDEO_MEDIATEK_VCODEC_SCP)
>  struct mtk_vcodec_fw *mtk_vcodec_fw_scp_init(struct mtk_vcodec_dev *dev);
> +#else
> +static inline struct mtk_vcodec_fw *
> +mtk_vcodec_fw_scp_init(struct mtk_vcodec_dev *dev)
> +{
> +	return ERR_PTR(-ENODEV);
> +}
> +#endif /* CONFIG_VIDEO_MEDIATEK_VCODEC_SCP */
>  
>  #endif /* _MTK_VCODEC_FW_PRIV_H_ */
> 


-- 
~Randy
Reported-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>