[PATCHv2 7/7] drm/omap: hdmi4: fix use of uninitialized var

Tomi Valkeinen tomi.valkeinen at ti.com
Thu Oct 10 06:47:21 UTC 2019

On 08/10/2019 17:21, Tony Lindgren wrote:
> * Tomi Valkeinen <tomi.valkeinen at ti.com> [191008 14:17]:
>> On 08/10/2019 17:13, Tony Lindgren wrote:
>>> * Tomi Valkeinen <tomi.valkeinen at ti.com> [190930 10:38]:
>>>> If use_mclk is false, mclk_mode is written to a register without
>>>> initialization. This doesn't cause any ill effects as the written value
>>>> is not used when use_mclk is false.
>>>> To fix this, write use_mclk only when use_mclk is true.
>>> Hey nice catch. Based on a quick test looks like this fixes an
>>> issue where power consumption stays higher after using HDMI.
>>> Would be nice to have merged in the v5.4-rc series:
>>> Tested-by: Tony Lindgren <tony at atomide.com>
>> Really? Ok, well, then it was a good random find =).
> Yeah so it seems :) Earlier I thought there's still some
> clkctrl setting wrong after using HDMI, but did not see
> anything diffing the clkctrl registers before and after
> and gave up.
>> I did already push this to drm-misc-next, as I thought it does not have any
>> real effect. I'll check if it's ok to push to drm-misc-fixes too, with Cc
>> stable.
> OK great thanks.

Pushing this to fixes too would cause conflicts, so we shouldn't push 
without good reason. How much power saving you see?

I think this can still be sent to stable later, after it has been merged 
to mainline.


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