Re: [PATCH V6 0/7] cpufreq: suspend early/resume late: dpm_{suspend|resume}()

On 02/17/2014 02:25 AM, Viresh Kumar wrote:

This patchset creates/calls cpufreq suspend/resume callbacks from dpm_{suspend|resume}() for handling suspend/resume of cpufreq governors and 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.
• Lan Tianyu (Intel) & Jinhyuk Choi (Broadcom) found an 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 fixed by this patch as we don't allow any operation on governors after device suspend and before device resume now.

The series, Tested-by: Stephen Warren swarren@nvidia.com

Patch 7/7, Acked-by: Stephen Warren swarren@nvidia.com