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[v1,1/2] drivers/video/fbdev: don't select DMA_CMA

Message ID 20210408092011.52763-2-david@redhat.com (mailing list archive)
State New
Headers show
Series drivers: don't select DMA_CMA or CMA | expand

Commit Message

David Hildenbrand April 8, 2021, 9:20 a.m. UTC
Random drivers should not override a user configuration of core knobs
(e.g., CONFIG_DMA_CMA=n). Use "imply" instead, to still respect
dependencies and manual overrides.

"This is similar to "select" as it enforces a lower limit on another
 symbol except that the "implied" symbol's value may still be set to n
 from a direct dependency or with a visible prompt."

Implying DRM_CMA should be sufficient, as that depends on CMA.

Note: If this is a real dependency, we should use "depends on DMA_CMA"
instead -  but I assume the driver can work without CMA just fine --
esp. when we wouldn't have HAVE_DMA_CONTIGUOUS or CMA right now.

Signed-off-by: David Hildenbrand <david@redhat.com>
---
 drivers/video/fbdev/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Mike Rapoport April 8, 2021, 9:56 a.m. UTC | #1
On Thu, Apr 08, 2021 at 11:20:10AM +0200, David Hildenbrand wrote:
> Random drivers should not override a user configuration of core knobs
> (e.g., CONFIG_DMA_CMA=n). Use "imply" instead, to still respect
> dependencies and manual overrides.
> 
> "This is similar to "select" as it enforces a lower limit on another
>  symbol except that the "implied" symbol's value may still be set to n
>  from a direct dependency or with a visible prompt."
> 
> Implying DRM_CMA should be sufficient, as that depends on CMA.

	  ^ DMA_CMA ?

> Note: If this is a real dependency, we should use "depends on DMA_CMA"
> instead -  but I assume the driver can work without CMA just fine --
> esp. when we wouldn't have HAVE_DMA_CONTIGUOUS or CMA right now.
> 
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
>  drivers/video/fbdev/Kconfig | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig
> index 4f02db65dede..d37cd5341e1b 100644
> --- a/drivers/video/fbdev/Kconfig
> +++ b/drivers/video/fbdev/Kconfig
> @@ -2186,7 +2186,7 @@ config FB_HYPERV
>  	select FB_CFB_COPYAREA
>  	select FB_CFB_IMAGEBLIT
>  	select FB_DEFERRED_IO
> -	select DMA_CMA if HAVE_DMA_CONTIGUOUS && CMA
> +	imply DMA_CMA
>  	help
>  	  This framebuffer driver supports Microsoft Hyper-V Synthetic Video.
>  
> -- 
> 2.30.2
>
diff mbox series

Patch

diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig
index 4f02db65dede..d37cd5341e1b 100644
--- a/drivers/video/fbdev/Kconfig
+++ b/drivers/video/fbdev/Kconfig
@@ -2186,7 +2186,7 @@  config FB_HYPERV
 	select FB_CFB_COPYAREA
 	select FB_CFB_IMAGEBLIT
 	select FB_DEFERRED_IO
-	select DMA_CMA if HAVE_DMA_CONTIGUOUS && CMA
+	imply DMA_CMA
 	help
 	  This framebuffer driver supports Microsoft Hyper-V Synthetic Video.