[PATCH 3.16 079/245] ACPI: PM: Avoid attaching ACPI PM domain to certain devices

Ben Hutchings
2020-04-23T23:19:20Z

From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>

commit b9ea0bae260f6aae546db224daa6ac1bd9d94b91 upstream.

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@intel.com>
Tested-by: Todd Brandt <todd.e.brandt@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/acpi/device_pm.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)

--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -1041,9 +1041,19 @@ static struct dev_pm_domain acpi_general
*/
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 -ENODEV;

if (dev->pm_domain)