[PATCH v1 2/2][RFT] ACPI: PM: Check states of power resources during initialization

Rafael J. Wysocki
2021-10-15T17:14:50Z

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

To avoid situations in which the actual states of certain ACPI power
resources are not known just because they have never been referenced
by any device configuration objects, check the initial states of all
power resources as soon as they are found in the ACPI namespace (and
fall back to turning them on if the state check fails).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---

Andreas, please test this patch (on top of the [1/2]) and let me know
if it works for you.

Thanks!

---
drivers/acpi/power.c | 30 +++++++++++++-----------------
1 file changed, 13 insertions(+), 17 deletions(-)

Index: linux-pm/drivers/acpi/power.c
===================================================================
--- linux-pm.orig/drivers/acpi/power.c
+++ linux-pm/drivers/acpi/power.c
@@ -923,6 +919,7 @@ struct acpi_device *acpi_add_power_resou
union acpi_object acpi_object;
struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
acpi_status status;
+ u8 state_dummy;
int result;

acpi_bus_get_device(handle, &device);
@@ -951,6 +948,10 @@ struct acpi_device *acpi_add_power_resou
resource->order = acpi_object.power_resource.resource_order;
resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;

+ /* Get the initial state or just flip it on if that fails. */
+ if (acpi_power_get_state(resource, &state_dummy))
+ __acpi_power_on(resource);
+
pr_info("%s [%s]\n", acpi_device_name(device), acpi_device_bid(device));

device->flags.match_driver = true;