diff options
| author | Mark Brown <broonie@linaro.org> | 2014-04-18 00:48:32 +0100 |
|---|---|---|
| committer | Mark Brown <broonie@linaro.org> | 2014-04-23 23:54:52 +0100 |
| commit | adb665056afe23db0687c1d1a208806c108add08 (patch) | |
| tree | 3a36a782bf18e04f5be85e4eded6b14a96b29c93 /include | |
| parent | 682a3d0201261152f489138d5f034742bccbfe9a (diff) | |
cpufreq: suspend governors on system suspend/hibernate
This patch adds cpufreq suspend/resume calls to dpm_{suspend|resume}()
for handling suspend/resume of cpufreq governors.
Lan Tianyu (Intel) & Jinhyuk Choi (Broadcom) found an issue where the
tunables configuration for clusters/sockets with non-boot CPUs was
lost after system suspend/resume, as we were notifying governors with
CPUFREQ_GOV_POLICY_EXIT on removal of the last CPU for that policy
which caused the tunables memory to be freed.
This is fixed by preventing any governor operations from being
carried out between the device suspend and device resume stages of
system suspend and resume, respectively.
We could have added these callbacks at dpm_{suspend|resume}_noirq()
level, but there is an additional problem that the majority of I/O
devices is already suspended at that point and if cpufreq drivers
want to change the frequency before suspending, then that not be
possible on some platforms (which depend on peripherals like i2c,
regulators, etc).
Reported-and-tested-by: Lan Tianyu <tianyu.lan@intel.com>
Reported-by: Jinhyuk Choi <jinchoi@broadcom.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
(cherry-picked from 2f0aea9363609433b38ab13f0f86f38372668c68)
Signed-off-by: Mark Brown <broonie@linaro.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/cpufreq.h | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 037d36ae63e5..00b0e0a9fca3 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -306,6 +306,18 @@ struct freq_attr { static struct freq_attr _name = \ __ATTR(_name, 0444, show_##_name, NULL) +#ifdef CONFIG_CPU_FREQ +void cpufreq_suspend(void); +void cpufreq_resume(void); +#else +static inline void cpufreq_suspend(void) {} +static inline void cpufreq_resume(void) {} +#endif + +/********************************************************************* + * CPUFREQ NOTIFIER INTERFACE * + *********************************************************************/ + #define cpufreq_freq_attr_ro_perm(_name, _perm) \ static struct freq_attr _name = \ __ATTR(_name, _perm, show_##_name, NULL) |