This patchset adds cpufreq callbacks to dpm_{suspend|resume}() for handling suspend/resume of cpufreq governors and core. This is required for early suspend and late resume of governors and cpufreq core.
There are multiple problems that are fixed by this patch: - Nishanth Menon (TI) found an interesting problem on his platform, OMAP. His board wasn't working well with suspend/resume as calls for removing non-boot CPUs was turning out into a call to drivers ->target() which then tries to play with regulators. But regulators and their I2C bus were already suspended and this resulted in a failure. Many platforms have such problems, samsung, tegra, etc.. They solved it with driver specific PM notifiers where they used to disable their driver's ->target() routine. Most of these are updated in this patchset to use new infrastructure.
- Lan Tianyu (Intel) & Jinhyuk Choi (Broadcom) found another issue where tunables configuration for clusters/sockets with non-boot CPUs was getting lost after suspend/resume, as we were notifying governors with CPUFREQ_GOV_POLICY_EXIT on removal of the last cpu for that policy and so deallocating memory for tunables. This is also fixed with this patch as don't allow any operation on Governors during suspend/resume now.
So to solve these issues we introduce early suspend and late resume callbacks which would remove need of cpufreq drivers to implement PM notifiers to disable transition after suspend and before resume.
@Nishanth: Can you please test V2 as well and confirm that suspend_noirq() doesn't work for you. I am sure it will not, but would be better if you confirm that.
Viresh Kumar (6): cpufreq: suspend governors on system suspend/hibernate cpufreq: call driver's suspend/resume for each policy cpufreq: Implement cpufreq_generic_suspend() cpufreq: exynos: Use cpufreq_generic_suspend() cpufreq: s5pv210: Use cpufreq_generic_suspend() cpufreq: Tegra: Use cpufreq_generic_suspend()
drivers/base/power/main.c | 5 ++ drivers/cpufreq/cpufreq.c | 133 +++++++++++++++++++++----------------- drivers/cpufreq/exynos-cpufreq.c | 97 ++------------------------- drivers/cpufreq/s5pv210-cpufreq.c | 49 +------------- drivers/cpufreq/tegra-cpufreq.c | 54 ++-------------- include/linux/cpufreq.h | 6 ++ 6 files changed, 99 insertions(+), 245 deletions(-)