From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sylwester Nawrocki <s.nawrocki@samsung.com>
Subject: Re: [PATCH v2 1/4] PM / Domains: Remove pm_genpd_dev_need_restore() API
Date: Wed, 01 Oct 2014 18:36:47 +0200
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To: Ulf Hansson <ulf.hansson@linaro.org>
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On 01/10/14 16:41, Ulf Hansson wrote:
> There are currently no users of this API, let's remove it.

The sad fact is that removal of pm_genpd_dev_need_restore() calls
from arch/arm/mach-exynos/pm_domains.c introduces regressions in
multiple exynos drivers (I'm sure it breaks media drivers).
I think before doing such changes all relevant drivers should be
updated first. I need to take a closer look again, but it seems
after dropping the pm_genpd_dev_need_restore() calls, client
driver's runtime_resume() callback is not being called in response
to first pm_runtime_get(_sync) call, even if a device is runtime
pm active.

More details can be found in commit ebc35c726298ba3fdebba316a
'ARM: EXYNOS: register devices in 'need_restore' state for pm_domains'.

The above only happens when devices are added to an inactive power
domain, then I guess patch 2/4 is also an attempt to address this
issue ?

--
Thanks,
Sylwester