Re: [PATCH v4 1/6] drm/dsi: check for CONFIG_OF when defining of_mipi_dsi_device_add

[Thierry Reding]

On Thu, Dec 10, 2015 at 06:11:35PM +0530, Archit Taneja wrote:
> of_mipi_dsi_device_add is used only when CONFIG_OF is enabled. It
> currently works if OF support is disabled, but this will change
> when we add more functionality to it.
> 
> Define the original func if CONFIG_OF is enabled. Define a dummy func
> otherwise.
> 
> Signed-off-by: Archit Taneja <architt@xxxxxxxxxxxxxx>
> ---
>  drivers/gpu/drm/drm_mipi_dsi.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c
> index 2d5ca8ee..bced235 100644
> --- a/drivers/gpu/drm/drm_mipi_dsi.c
> +++ b/drivers/gpu/drm/drm_mipi_dsi.c
> @@ -129,6 +129,7 @@ static int mipi_dsi_device_add(struct mipi_dsi_device *dsi)
>  	return device_add(&dsi->dev);
>  }
>  
> +#if IS_ENABLED(CONFIG_OF)
>  static struct mipi_dsi_device *
>  of_mipi_dsi_device_add(struct mipi_dsi_host *host, struct device_node *node)
>  {
> @@ -170,6 +171,13 @@ of_mipi_dsi_device_add(struct mipi_dsi_host *host, struct device_node *node)
>  
>  	return dsi;
>  }
> +#else
> +static struct mipi_dsi_device *
> +of_mipi_dsi_device_add(struct mipi_dsi_host *host, struct device_node *node)
> +{
> +	return NULL;
> +}
> +#endif

The OF implementation of this function never returns NULL, so perhaps
this should return an ERR_PTR()-encoded error code instead? This isn't
really important because we never check the return value in the one
call-site that we have, which I guess could be an argument for removing
the return value altogether...

Thierry

Attachment: signature.asc
Description: PGP signature