[SRU][PATCH 2/2][N] ACPI: PM: s2idle: Evaluate all Low-Power S0 Idle _DSM functions

[Thibault Ferrante]

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

BugLink: https://bugs.launchpad.net/bugs/2069231

Commit 073237281a50 ("ACPI: PM: s2idle: Enable Low-Power S0 Idle MSFT
UUID for non-AMD systems") attempted to avoid evaluating the same Low-
Power S0 Idle _DSM functions for different UUIDs, but that turns out to
be a mistake, because some systems in the field are adversely affected
by it.

Address this by allowing all Low-Power S0 Idle _DSM functions to be
evaluated, but still print the message regarding duplication of Low-
Power S0 Idle _DSM function sets for different UUIDs.

Fixes: 073237281a50 ("ACPI: PM: s2idle: Enable Low-Power S0 Idle MSFT UUID for non-AMD systems")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218750
Reported-and-tested-by: Mark Pearson <mpearson at lenovo.com>
Suggested-by: Mario Limonciello <mario.limonciello at amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki at intel.com>
Reviewed-by: Mario Limonciello <mario.limonciello at amd.com>
(cherry picked from commit 68301ef471b63f25d6e6144a0820fea52257a34a)
Signed-off-by: Thibault Ferrante <thibault.ferrante at canonical.com>
---
 drivers/acpi/x86/s2idle.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/acpi/x86/s2idle.c b/drivers/acpi/x86/s2idle.c
index cd84af23f7ea..dd0b40b9bbe8 100644
--- a/drivers/acpi/x86/s2idle.c
+++ b/drivers/acpi/x86/s2idle.c
@@ -492,16 +492,14 @@ static int lps0_device_attach(struct acpi_device *adev,
 			unsigned int func_mask;
 
 			/*
-			 * Avoid evaluating the same _DSM function for two
-			 * different UUIDs and prioritize the MSFT one.
+			 * Log a message if the _DSM function sets for two
+			 * different UUIDs overlap.
 			 */
 			func_mask = lps0_dsm_func_mask & lps0_dsm_func_mask_microsoft;
-			if (func_mask) {
+			if (func_mask)
 				acpi_handle_info(adev->handle,
 						 "Duplicate LPS0 _DSM functions (mask: 0x%x)\n",
 						 func_mask);
-				lps0_dsm_func_mask &= ~func_mask;
-			}
 		}
 	}
 
-- 
2.43.0