Re: [PATCH 1/3] MMC / PM: Make it possible to use PM QoS latency constraints

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Sunday, March 04, 2012, Linus Walleij wrote:
> On Sun, Mar 4, 2012 at 1:02 AM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
> 
> > A runtime suspend of an MMC controller belonging to a power domain
> > or, in a more complicated scenario, a runtime suspend of another
> > device in the same power domain, may cause power to be removed from
> > the entire domain.  In that case, the amount of time necessary to
> > runtime-resume the MMC controller is often substantially greater
> > than the time needed to enable its clock.  That may hurt performance
> > in some situations, because user data may need to wait for the
> > controller to become operational, so we should make it possible to
> > prevent that from happening.
> >
> > For this reason, introduce a new sysfs attribute for MMC hosts,
> > pm_latency_limit_ms, allowing user space to specify the upper bound
> > of the time necessary to bring the host up after it has been
> > runtime-suspended.  However, make it appear ony for the hosts whose
> > drivers declare support for PM QoS by populating the pm_qos_req
> > member of struct mmc_host before registering the host.
> >
> > Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
> 
> Overall I've already ACKed this I think, looking good...
> Acked-by: Linus Walleij <linus.walleij@linaro.org>

Thanks!

I have a new version, though, (will be sent in a while), but hopefully
your ACK will still apply. :-)

Rafael