Re: [PATCH] implement pm_ops.valid for everybody

[David Brownell <david-b@pacbell.net>]

On Saturday 24 March 2007 2:01 pm, Johannes Berg wrote:
> On Sat, 2007-03-24 at 13:49 -0700, David Brownell wrote:
> 
> > You seem to have overlooked the clk_must_disable() patches I
> > recently re-sent.  In conjunction with the driver model wakeup
> > flags, that can solve the problem on every SOC platform I've
> > had a reason to look at ... see how it works for AT91 USB.
> 
> In fact, I looked at those, and it's actually useful on powermac laptops
> (powerbooks/ibooks) as well, there are some sound clocks that could be
> managed with it.

Interesting.  I've sort of assumed <linux/clk.h> didn't get much
use outside the embedded arch code (ARM, AVR32, SH pending, ...)
so far ... there's no good technical reason for that of course!


> > No, let's not complexify that pm_message_t mistake any further.
> 
> I second that. Drivers can't really know what the precise semantics of
> any state are across platforms, especially drivers that are shared
> between different platforms but where the hw could be wired up
> differently.

Even within one platform there can be board-specific diferences,
and different chip revisions may work differently.

- Dave