On Wed, 2019-12-04 at 02:54 +0100, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> Certain ACPI-enumerated devices represented as platform devices in
> Linux, like fans, require special low-level power management handling
> implemented by their drivers that is not in agreement with the ACPI
> PM domain behavior. That leads to problems with managing ACPI fans
> during system-wide suspend and resume.
>
> For this reason, make acpi_dev_pm_attach() skip the affected devices
> by adding a list of device IDs to avoid to it and putting the IDs of
> the affected devices into that list.
>
> Fixes: e5cc8ef31267 (ACPI / PM: Provide ACPI PM callback routines for
> subsystems)
> Reported-by: Zhang Rui <rui.zhang@xxxxxxxxx>
> Cc: 3.10+ <stable@xxxxxxxxxxxxxxx> # 3.10+
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> ---
>
> Rui,
>
> Please test this on the machine(s) affected by the fan suspend/resume
> issues.
Sure, Todd and I will re-run stress test with this patch applied when
5.5-rc1 released.
thanks,
rui
>
> I don't really see any cleaner way to address this problem, because
> the
> ACPI PM domain should not be used with the devices in question even
> if
> the driver that binds to them is not loaded.
>
> Cheers,
> Rafael
>
> ---
> drivers/acpi/device_pm.c | 12 +++++++++++-
> 1 file changed, 11 insertions(+), 1 deletion(-)
>
> Index: linux-pm/drivers/acpi/device_pm.c
> ===================================================================
> --- linux-pm.orig/drivers/acpi/device_pm.c
> +++ linux-pm/drivers/acpi/device_pm.c
> @@ -1314,9 +1314,19 @@ static void acpi_dev_pm_detach(struct de
> */
> int acpi_dev_pm_attach(struct device *dev, bool power_on)
> {
> + /*
> + * Skip devices whose ACPI companions match the device IDs
> below,
> + * because they require special power management handling
> incompatible
> + * with the generic ACPI PM domain.
> + */
> + static const struct acpi_device_id special_pm_ids[] = {
> + {"PNP0C0B", }, /* Generic ACPI fan */
> + {"INT3404", }, /* Fan */
> + {}
> + };
> struct acpi_device *adev = ACPI_COMPANION(dev);
>
> - if (!adev)
> + if (!adev || !acpi_match_device_ids(adev, special_pm_ids))
> return 0;
>
> /*
>
>
>
