[PATCH v5 4/5] PM: hibernate: add new api pm_hibernate_is_recovering()

[Mario Limonciello]

On 7/9/2025 6:05 AM, Samuel Zhang wrote:
> dev_pm_ops.thaw() is called in following cases:
> * normal case: after hibernation image has been created.
> * error case 1: creation of a hibernation image has failed.
> * error case 2: restoration from a hibernation image has failed.
> 
> For normal case, it is called mainly for resume storage devices for
> saving the hibernation image. Other devices that are not involved
> in the image saving do not need to resume the device. But since there's
> no api to know which case thaw() is called, device drivers can't
> conditionally resume device in thaw().
> 
> The new pm_hibernate_is_recovering() is such a api to query if thaw() is
> called in normal case.
> 
> Signed-off-by: Samuel Zhang <guoqing.zhang at amd.com>

This patch also doesn't apply to linux-next.  Please rebase it.

Applying: PM: hibernate: add new api pm_hibernate_is_recovering()
error: patch failed: drivers/base/power/main.c:63
error: drivers/base/power/main.c: patch does not apply
Patch failed at 0004 PM: hibernate: add new api pm_hibernate_is_recovering()
hint: Use 'git am --show-current-patch=diff' to see the failed patch

> ---
>   drivers/base/power/main.c | 14 ++++++++++++++
>   include/linux/pm.h        |  2 ++
>   2 files changed, 16 insertions(+)
> 
> diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
> index 40e1d8d8a589..ff78cf96f795 100644
> --- a/drivers/base/power/main.c
> +++ b/drivers/base/power/main.c
> @@ -63,6 +63,20 @@ static LIST_HEAD(dpm_noirq_list);
>   static DEFINE_MUTEX(dpm_list_mtx);
>   static pm_message_t pm_transition;
>   
> +/**
> + * pm_hibernate_is_recovering - if recovering from hibernate due to error.
> + *
> + * Used to query if dev_pm_ops.thaw() is called for normal hibernation case or
> + * recovering from some error.
> + *
> + * Return: true for error case, false for normal case.
> + */
> +bool pm_hibernate_is_recovering(void)
> +{
> +	return pm_transition.event == PM_EVENT_RECOVER;
> +}
> +EXPORT_SYMBOL_GPL(pm_hibernate_is_recovering);
> +
>   static int async_error;
>   
>   static const char *pm_verb(int event)
> diff --git a/include/linux/pm.h b/include/linux/pm.h
> index 78855d794342..f54a803f2afb 100644
> --- a/include/linux/pm.h
> +++ b/include/linux/pm.h
> @@ -657,6 +657,8 @@ struct pm_subsys_data {
>   #define DPM_FLAG_SMART_SUSPEND		BIT(2)
>   #define DPM_FLAG_MAY_SKIP_RESUME	BIT(3)
>   
> +bool pm_hibernate_is_recovering(void);
> +
>   struct dev_pm_info {
>   	pm_message_t		power_state;
>   	bool			can_wakeup:1;