Re: [PATCH 0/4] drm/atmel-hlcdc: fix plane clipping/rotation issues

From: Nicolas.Ferre
Date: Fri Jan 11 2019 - 09:19:01 EST


On 10/01/2019 at 18:45, Boris Brezillon wrote:
> On Thu, 10 Jan 2019 15:10:28 +0000
> Peter Rosin <peda@xxxxxxxxxx> wrote:
>
>> Hi!
>>
>> I found an unfortunate issue while recoding plane handling to use
>> drm_atomic_helper_check_plane_state(). The driver rotates clockwise,
>> which is not correct. I simply fixed it (patch 1/4), but maybe that
>> will cause regressions for unsuspecting users who simply assumed
>> that the clockwise rotation was correct? I don't know what to do
>> about that? Adding an option to get the old broken behavior seems
>> useless, wouldn't it be just as easy to just fix whatever app to
>> rotate the other way instead of adding an option somewhere?
>
> Hm, rotation support has been added before the standard rotation
> property was created, and at that time I assumed rotation was clockwise
> (which apparently was an unwise choice). Anyway, I don't have a
> solution for this problem, so I'll let Nicolas decide if it's
> acceptable to change the rotation behavior.

Yes, being consistent with standard DRM sub-system is far more important
in my opinion.

Best regards,
Nicolas

>> I have only tested this series on sama5d3, but I did check the docs
>> for various other chips (sama5d2, sama5d4, sam9n12, sam9g15, sam9g35
>> and sam9x35) supported by the driver (relevant to patch 4/4).
>
> Thanks for addressing those problems.
>
>>
>> Cheers,
>> Peter
>>
>> Peter Rosin (4):
>> drm/atmel-hlcdc: rotate planes counterclockwise
>> drm/atmel-hlcdc: do not swap w/h of the crtc when a plane is rotated
>> drm/atmel-hlcdc: fix clipping of planes
>> drm/atmel-hlcdc: do not immediately disable planes, wait for next
>> frame
>>
>> drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_plane.c | 179 +++++++++---------------
>> 1 file changed, 67 insertions(+), 112 deletions(-)
>>
>
>


--
Nicolas Ferre