Re: [PATCH] drm/msm/disp/dpu: consider SSPP line width during mode valid

From: Dmitry Baryshkov

Date: Sat Mar 28 2026 - 20:25:26 EST


On Sat, Mar 28, 2026 at 10:45:35PM +0530, Vishnu Saini wrote:
> Few targets have lesser SSPP line width compared to mixer width,
> SSPP line width also needs to be considered during mode valid
> to avoid failures during atomic_check.

Technically this is not correct. There is no requirement for the
planes to cover the whole CRTC. Nor is there a requirement to use only 2
rectangles to cover the screen. As such, it is perfectly fine in
mode_valid, if CRTC is wider than 2x max_linewidth. It would be an error
if the user tries to stretch 2 rectangles in such a case.

>
> Signed-off-by: Vishnu Saini <vishnu.saini@xxxxxxxxxxxxxxxx>
> ---
> drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 12 ++++++++----
> 1 file changed, 8 insertions(+), 4 deletions(-)
>

--
With best wishes
Dmitry