[PATCH v10 09/18] drm: exynos: dsi: Add atomic check

Frieder Schrempf frieder.schrempf at kontron.de
Thu Dec 15 00:40:59 PST 2022


On 15.12.22 09:39, Frieder Schrempf wrote:
> On 14.12.22 13:58, Jagan Teki wrote:
>> Look like an explicit fixing up of mode_flags is required for DSIM IP
>> present in i.MX8M Mini/Nano SoCs.
>>
>> At least the LCDIF + DSIM needs active low sync polarities in order
>> to correlate the correct sync flags of the surrounding components in
>> the chain to make sure the whole pipeline can work properly.
>>
>> On the other hand the i.MX 8M Mini Applications Processor Reference Manual,
>> Rev. 3, 11/2020 says.
>> "13.6.3.5.2 RGB interface
>>  Vsync, Hsync, and VDEN are active high signals."
>>
>> i.MX 8M Mini Applications Processor Reference Manual Rev. 3, 11/2020
>> 3.6.3.5.2 RGB interface
>> i.MX 8M Nano Applications Processor Reference Manual Rev. 2, 07/2022
>> 13.6.2.7.2 RGB interface
>> both claim "Vsync, Hsync, and VDEN are active high signals.", the
>> LCDIF must generate inverted HS/VS/DE signals, i.e. active LOW.
>>
>> No clear evidence about whether it can be documentation issues or
>> something, so added a comment FIXME for this and updated the active low
>> sync polarities using SAMSUNG_DSIM_TYPE_IMX8MM hw_type.

By the way, the commit message mentions a FIXME comment above. But it's
not in the patch. The commit message probably needs an update.

>>
>> Comments are suggested by Marek Vasut.
>>
>> Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
> 
> Reviewed-by: Frieder Schrempf <frieder.schrempf at kontron.de>



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