[PATCH 2/2] drm/msm: Don't provide 'is_enabled' PLL clk_ops

[Archit Taneja]

On 10/26/2016 01:58 AM, Stephen Boyd wrote:
> On 10/25, Archit Taneja wrote:
>> The DSI/HDMI PLLs in MSM require resources like interface clocks, power
>> domains to be enabled before we can access their registers.
>>
>> The clock framework doesn't have a mechanism at the moment where we can
>> tie such resources to a clock, so we make sure that the KMS driver enables
>> these resources whenever a PLL is expected to be in use.
>>
>> One place where we can't ensure the resource dependencies are met is when
>> the clock framework tries to disable unused clocks. The KMS driver doesn't
>> know when the clock framework calls the is_enabled clk_op, and hence can't
>> enable interface clocks/power domains beforehand.
>>
>> We remove the is_enabled clk_ops from the PLL clocks for now since they
>> aren't mandatory. This needs to be revisited, since bootloaders can enable
>> display, the enable count maintained by clock framework wouldn't work in
>> such cases.
>>
>> Cc: Stephen Boyd <sboyd at codeaurora.org>
>> Signed-off-by: Archit Taneja <architt at codeaurora.org>
>> ---
>
> Why not use the CLK_IGNORE_UNUSED flag for now? That does
> essentially the same thing without requiring us to reintroduce
> this code later on.

Right, that makes more sense. Will use the flag.

Thanks,
Archit

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