Re: [PATCH v3] PM / suspend: Export pm_suspend_target_state

From: Rafael J. Wysocki
Date: Mon Jul 17 2017 - 19:32:47 EST


On Monday, July 17, 2017 03:10:59 PM Florian Fainelli wrote:
> Have the core suspend/resume framework store the system-wide suspend
> state (suspend_state_t) we are about to enter, and expose it to drivers
> via pm_suspend_target_state in order to retrieve that. The state is
> assigned in suspend_devices_and_enter().
>
> This is useful for platform specific drivers that may need to take a
> slightly different suspend/resume path based on the system's
> suspend/resume state being entered.
>
> Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
> ---
> Changes in v3:
>
> - just export pm_suspend_target_state without a helper function
>
> Changes in v2:
>
> - rename platform_suspend_target_state() -> suspend_target_state()
> - directly export the suspend_state_t value and assign it in
> suspend_devices_and_enter()
>
> include/linux/suspend.h | 1 +
> kernel/power/suspend.c | 4 ++++
> 2 files changed, 5 insertions(+)
>
> diff --git a/include/linux/suspend.h b/include/linux/suspend.h
> index 0b1cf32edfd7..2159f6841768 100644
> --- a/include/linux/suspend.h
> +++ b/include/linux/suspend.h
> @@ -427,6 +427,7 @@ extern int unregister_pm_notifier(struct notifier_block *nb);
> /* drivers/base/power/wakeup.c */
> extern bool events_check_enabled;
> extern unsigned int pm_wakeup_irq;
> +extern suspend_state_t pm_suspend_target_state;
>
> extern bool pm_wakeup_pending(void);
> extern void pm_system_wakeup(void);
> diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
> index 3ecf275d7e44..1aecdaf22ab5 100644
> --- a/kernel/power/suspend.c
> +++ b/kernel/power/suspend.c
> @@ -47,6 +47,8 @@ const char *mem_sleep_states[PM_SUSPEND_MAX];
>
> suspend_state_t mem_sleep_current = PM_SUSPEND_FREEZE;
> static suspend_state_t mem_sleep_default = PM_SUSPEND_MEM;
> +suspend_state_t pm_suspend_target_state;
> +EXPORT_SYMBOL_GPL(pm_suspend_target_state);
>
> unsigned int pm_suspend_global_flags;
> EXPORT_SYMBOL_GPL(pm_suspend_global_flags);
> @@ -456,6 +458,8 @@ int suspend_devices_and_enter(suspend_state_t state)
> if (!sleep_state_supported(state))
> return -ENOSYS;
>
> + pm_suspend_target_state = state;
> +
> error = platform_suspend_begin(state);
> if (error)
> goto Close;
>

And please clear pm_suspend_target_state before returning from
suspend_devices_and_enter().

Thanks,
Rafael