[PATCH] drm/amd/display: Fix BUG_ON during CRTC atomic check update

[Leo Li]

On 2018-05-28 11:20 AM, Michel Dänzer wrote:
> On 2018-05-28 05:06 PM, sunpeng.li at amd.com wrote:
>> From: "Leo (Sunpeng) Li" <sunpeng.li at amd.com>
>>
>> For cases where the CRTC is inactive (DPMS off), where a modeset is not
>> required, yet the CRTC is still in the atomic state, we should not
>> attempt to update anything on it.
>>
>> Previously, we were relying on the modereset_required() helper to check
> 
> This should say "modeset_required()", right?
> 

modereset_required() here refers to an amdgpu_dm specific helper, which 
was previously being used. It essentially returns true if the CRTC is 
*being* disabled or made inactive, not if it's currently disabled or 
inactive.

> 
>> the above condition. However, the function returns false immediatly if
> 
> "immediately" (missing "e") >
>> a modeset is not required, ignoring the CRTC's enable/active state
>> flags. The correct way to filter is by looking at these flags instead.
>>
>> Signed-off-by: Leo (Sunpeng) Li <sunpeng.li at amd.com>
>> Reviewed-by: Harry Wentland <harry.wentland at amd.com>
> 
> Please add the following tags to the commit log:
> 
> Fixes: e277adc5a06c "drm/amd/display: Hookup color management functions"
> Tested-by: Michel Dänzer <michel.daenzer at amd.com>
> 

Will do.

Leo

>