[PATCH 3/4] acpi/x86: s2idle: Add module parameter to prefer Microsoft GUID

From: Mario Limonciello
Date: Fri Sep 09 2022 - 14:05:56 EST


OEMs have made some mistakes in the past for the AMD GUID support
and not populated the method properly. To add an escape hatch for
this problem introduce a module parameter that can force using
the Microsoft GUID.

This is intentionally introduced to both Intel and AMD codepaths
to allow using the parameter as a debugging tactic on either.

Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
drivers/acpi/x86/s2idle.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/drivers/acpi/x86/s2idle.c b/drivers/acpi/x86/s2idle.c
index a8256e5a0e8a..a9b0f2b54a1c 100644
--- a/drivers/acpi/x86/s2idle.c
+++ b/drivers/acpi/x86/s2idle.c
@@ -27,6 +27,10 @@ static bool sleep_no_lps0 __read_mostly;
module_param(sleep_no_lps0, bool, 0644);
MODULE_PARM_DESC(sleep_no_lps0, "Do not use the special LPS0 device interface");

+static bool prefer_microsoft_guid __read_mostly;
+module_param(prefer_microsoft_guid, bool, 0644);
+MODULE_PARM_DESC(prefer_microsoft_guid, "Prefer selecting Microsoft GUID for LPS0 device");
+
static const struct acpi_device_id lps0_device_ids[] = {
{"PNP0D80", },
{"", },
@@ -402,6 +406,9 @@ static int lps0_device_attach(struct acpi_device *adev,
if (lps0_device_handle)
return 0;

+ lps0_dsm_func_mask_microsoft = validate_dsm(adev->handle,
+ ACPI_LPS0_DSM_UUID_MICROSOFT, 0,
+ &lps0_dsm_guid_microsoft);
if (acpi_s2idle_vendor_amd()) {
static const struct acpi_device_id *dev_id;
const struct amd_lps0_hid_device_data *data;
@@ -416,16 +423,12 @@ static int lps0_device_attach(struct acpi_device *adev,
rev_id = data->rev_id;
lps0_dsm_func_mask = validate_dsm(adev->handle,
ACPI_LPS0_DSM_UUID_AMD, rev_id, &lps0_dsm_guid);
- lps0_dsm_func_mask_microsoft = validate_dsm(adev->handle,
- ACPI_LPS0_DSM_UUID_MICROSOFT, 0,
- &lps0_dsm_guid_microsoft);
if (lps0_dsm_func_mask > 0x3 && data->check_off_by_one) {
lps0_dsm_func_mask = (lps0_dsm_func_mask << 1) | 0x1;
acpi_handle_debug(adev->handle, "_DSM UUID %s: Adjusted function mask: 0x%x\n",
ACPI_LPS0_DSM_UUID_AMD, lps0_dsm_func_mask);
} else if (lps0_dsm_func_mask_microsoft > 0 && data->prefer_amd_guid &&
- (!strcmp(hid, "AMDI0007") ||
- !strcmp(hid, "AMDI0008"))) {
+ !prefer_microsoft_guid) {
lps0_dsm_func_mask_microsoft = -EINVAL;
acpi_handle_debug(adev->handle, "_DSM Using AMD method\n");
}
@@ -433,7 +436,8 @@ static int lps0_device_attach(struct acpi_device *adev,
rev_id = 1;
lps0_dsm_func_mask = validate_dsm(adev->handle,
ACPI_LPS0_DSM_UUID, rev_id, &lps0_dsm_guid);
- lps0_dsm_func_mask_microsoft = -EINVAL;
+ if (!prefer_microsoft_guid)
+ lps0_dsm_func_mask_microsoft = -EINVAL;
}

if (lps0_dsm_func_mask < 0 && lps0_dsm_func_mask_microsoft < 0)
--
2.34.1