From 21ba237926227121dacccaf5d7863b0cb50f3eda Mon Sep 17 00:00:00 2001
From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Date: Tue, 25 Jun 2019 14:04:45 +0200
Subject: [PATCH] ACPI: PM: Avoid evaluating _PS3 on transitions from D3hot to D3cold
Git-commit: 21ba237926227121dacccaf5d7863b0cb50f3eda
Patch-mainline: v5.3-rc1
References: bsc#1051510

If the power state of a device with ACPI PM is changed from D3hot to
D3cold, it merely is a matter of dropping references to additional
power resources (specifically, those in the list returned by _PR3),
and the _PS3 method should not be invoked for the device then (as
it has already been evaluated during the previous transition to
D3hot).

Fixes: 20dacb71ad28 (ACPI / PM: Rework device power management to follow ACPI 6)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/acpi/device_pm.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
index b859d75eaf9f..3269a4e8b902 100644
--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -210,9 +210,15 @@ int acpi_device_set_power(struct acpi_device *device, int state)
 			return -ENODEV;
 		}
 
-		result = acpi_dev_pm_explicit_set(device, state);
-		if (result)
-			goto end;
+		/*
+		 * If the device goes from D3hot to D3cold, _PS3 has been
+		 * evaluated for it already, so skip it in that case.
+		 */
+		if (device->power.state < ACPI_STATE_D3_HOT) {
+			result = acpi_dev_pm_explicit_set(device, state);
+			if (result)
+				goto end;
+		}
 
 		if (device->power.flags.power_resources)
 			result = acpi_power_transition(device, target_state);
-- 
2.16.4