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

[Stephen Boyd <sboyd@codeaurora.org>]

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@codeaurora.org>
> Signed-off-by: Archit Taneja <architt@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.

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