[PATCH 4.17 023/324] ACPI / EC: Use ec_no_wakeup on Thinkpad X1 Carbon 6th

From: Greg Kroah-Hartman
Date: Thu Aug 23 2018 - 04:39:52 EST


4.17-stable review patch. If anyone has any objections, please let me know.

------------------

From: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>

[ Upstream commit 8195a655e5ce09550aff81b2573d9b015d520cb9 ]

On this system EC interrupt triggers constantly kicking devices out of
low power states and thus blocking power management. The system also has
a PCIe root port hosting Alpine Ridge Thunderbolt controller and it
never gets a chance to go to D3cold because of this.

Since the power button works the same regardless if EC interrupt is
enabled or not during s2idle, add a quirk for this machine that sets
ec_no_wakeup=true preventing spurious wakeups.

Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/acpi/ec.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)

--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -2031,6 +2031,17 @@ static inline void acpi_ec_query_exit(vo
}
}

+static const struct dmi_system_id acpi_ec_no_wakeup[] = {
+ {
+ .ident = "Thinkpad X1 Carbon 6th",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "20KGS3JF01"),
+ },
+ },
+ { },
+};
+
int __init acpi_ec_init(void)
{
int result;
@@ -2041,6 +2052,15 @@ int __init acpi_ec_init(void)
if (result)
return result;

+ /*
+ * Disable EC wakeup on following systems to prevent periodic
+ * wakeup from EC GPE.
+ */
+ if (dmi_check_system(acpi_ec_no_wakeup)) {
+ ec_no_wakeup = true;
+ pr_debug("Disabling EC wakeup on suspend-to-idle\n");
+ }
+
/* Drivers must be started after acpi_ec_query_init() */
dsdt_fail = acpi_bus_register_driver(&acpi_ec_driver);
/*