[SRU][OEM-5.6][PATCH 1/1] UBUNTU: SAUCE: ACPI: avoid auto-wakeup with an _OSI string

[Alex Hung]

Some TGL systems wake up automatically from s2idle when connecting to
a docking station with a monitor. The wake-up events are generated when
BIOS sets ALL_MONITOR_OFF for power-saving on TGL systems.

A BIOS workaround is used to skip ALL_MONITOR_OFF with an _OSI string
"Linux-Dell-USB4-Wakeup".

BugLink: http://bugs.launchpad.net/bugs/1902577

Signed-off-by: Alex Hung <alex.hung at canonical.com>
---
 drivers/acpi/osi.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/acpi/osi.c b/drivers/acpi/osi.c
index 6fce7fb..69f8820 100644
--- a/drivers/acpi/osi.c
+++ b/drivers/acpi/osi.c
@@ -68,6 +68,12 @@ osi_setup_entries[OSI_STRING_ENTRIES_MAX] __initdata = {
 	 * hybrid graphics supports.
 	 */
 	{"Linux-HPI-Hybrid-Graphics", true},
+	/*
+	 * Linux-Dell-USB4-Wakeup is used by BIOS to workaround auto wakeup
+	 * on Tigerlake. This is done by skipping ALL_MONITOR_OFF when systems
+	 * are going to s2idle.
+	 */
+	{"Linux-Dell-USB4-Wakeup", true},
 };
 
 static u32 acpi_osi_handler(acpi_string interface, u32 supported)
-- 
2.7.4