[PATCH] drm: bridge: fsl-ldb: fixup mode on freq mismatch

Nikolaus Voss nv at vosn.de
Mon Dec 2 17:03:16 UTC 2024


On 02.12.2024 13:56, Marek Vasut wrote:
> On 12/2/24 7:32 AM, Liu Ying wrote:
>> On 11/27/2024, Nikolaus Voss wrote:
>>> LDB clock has to be a fixed multiple of the pixel clock.
>>> As LDB and pixel clock are derived from different clock sources
>>> (at least on imx8mp), this constraint cannot be satisfied for
>>> any pixel clock, which leads to flickering and incomplete
>>> lines on the attached display.
>>> 
>>> To overcome this, check this condition in mode_fixup() and
>>> adapt the pixel clock accordingly.
>>> 
>>> Cc: <stable at vger.kernel.org>
>> 
>> It looks like stable is not effectively Cc'ed.
>> Need a Fixes tag?
> Isn't this fix effectively superseded by series
> 
> [PATCH 0/5] clk: Fix simple video pipelines on i.MX8
> 
> ?

Maybe. I wasn't aware of the series. Looking at it, the change is
rather complex and not suitable for the stable series.

My intention was to get a simple fix which doesn't potentially
break anything. It wouldn't even break the patch series you mentioned.

-- 
Nikolaus Voss


More information about the dri-devel mailing list