Re: [RFT PATCH] drm/exynos: Enable DP clock to fix display on Exynos5250 and other

From: Kevin Hilman
Date: Thu Apr 30 2015 - 11:44:58 EST

Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx> writes:

> 2015-04-30 2:31 GMT+09:00 Kevin Hilman <khilman@xxxxxxxxxx>:
>> Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx> writes:
>>> After adding display power domain for Exynos5250 in commit
>>> 2d2c9a8d0a4f ("ARM: dts: add display power domain for exynos5250") the
>>> display on Chromebook Snow and others stopped working after boot.
>>> The reason for this suggested Andrzej Hajda: the DP clock was disabled.
>>> This clock is required by Display Port and is enabled by bootloader.
>>> However when FIMD driver probing was deferred, the display power domain
>>> was turned off. This effectively reset the value of DP clock enable
>>> register.
>>> When exynos-dp is later probed, the clock is not enabled and display is
>>> not properly configured:
>>> exynos-dp 145b0000.dp-controller: Timeout of video streamclk ok
>>> exynos-dp 145b0000.dp-controller: unable to config video
>>> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
>>> Reported-by: Javier Martinez Canillas <javier.martinez@xxxxxxxxxxxxxxx>
>>> Fixes: 2d2c9a8d0a4f ("ARM: dts: add display power domain for exynos5250")
>>> Cc: <stable@xxxxxxxxxxxxxxx>
>>> ---
>>> This should fix issue reported by Javier [1][2].
>>> Tested on Chromebook Snow (Exynos 5250). More testing would be great,
>>> especially on other Exynos 5xxx products.
>> I hoped to try this on my exynos5 boards, but it doesn't seem to apply
>> to linux-next or to Linus' master branch.
>> Are there some other dependencies here?
> It is already applied:

Er, yup. That would explain it. ;)

Sorry for the noise,

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