[PATCH 4.4 6/7] platform/x86: acer-wmi: Add new force_caps module parameter

From: gregkh
Date: Wed Mar 10 2021 - 08:30:33 EST


From: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

From: Hans de Goede <hdegoede@xxxxxxxxxx>

[ Upstream commit 39aa009bb66f9d5fbd1e58ca4aa03d6e6f2c9915 ]

Add a new force_caps module parameter to allow overriding the drivers
builtin capability detection mechanism.

This can be used to for example:
-Disable rfkill functionality on devices where there is an AA OEM DMI
record advertising non functional rfkill switches
-Force loading of the driver on devices with a missing AA OEM DMI record

Note that force_caps is -1 when unset, this allows forcing the
capability field to 0, which results in acer-wmi only providing WMI
hotkey handling while disabling all other (led, rfkill, backlight)
functionality.

Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20201019185628.264473-4-hdegoede@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/platform/x86/acer-wmi.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/platform/x86/acer-wmi.c b/drivers/platform/x86/acer-wmi.c
index b336f2620f9d..e4f278fa6d69 100644
--- a/drivers/platform/x86/acer-wmi.c
+++ b/drivers/platform/x86/acer-wmi.c
@@ -229,6 +229,7 @@ static int mailled = -1;
static int brightness = -1;
static int threeg = -1;
static int force_series;
+static int force_caps = -1;
static bool ec_raw_mode;
static bool has_type_aa;
static u16 commun_func_bitmap;
@@ -238,11 +239,13 @@ module_param(mailled, int, 0444);
module_param(brightness, int, 0444);
module_param(threeg, int, 0444);
module_param(force_series, int, 0444);
+module_param(force_caps, int, 0444);
module_param(ec_raw_mode, bool, 0444);
MODULE_PARM_DESC(mailled, "Set initial state of Mail LED");
MODULE_PARM_DESC(brightness, "Set initial LCD backlight brightness");
MODULE_PARM_DESC(threeg, "Set initial state of 3G hardware");
MODULE_PARM_DESC(force_series, "Force a different laptop series");
+MODULE_PARM_DESC(force_caps, "Force the capability bitmask to this value");
MODULE_PARM_DESC(ec_raw_mode, "Enable EC raw mode");

struct acer_data {
@@ -2150,7 +2153,7 @@ static int __init acer_wmi_init(void)
}
/* WMID always provides brightness methods */
interface->capability |= ACER_CAP_BRIGHTNESS;
- } else if (!wmi_has_guid(WMID_GUID2) && interface && !has_type_aa) {
+ } else if (!wmi_has_guid(WMID_GUID2) && interface && !has_type_aa && force_caps == -1) {
pr_err("No WMID device detection method found\n");
return -ENODEV;
}
@@ -2180,6 +2183,9 @@ static int __init acer_wmi_init(void)
if (acpi_video_get_backlight_type() != acpi_backlight_vendor)
interface->capability &= ~ACER_CAP_BRIGHTNESS;

+ if (force_caps != -1)
+ interface->capability = force_caps;
+
if (wmi_has_guid(WMID_GUID3)) {
if (ec_raw_mode) {
if (ACPI_FAILURE(acer_wmi_enable_ec_raw())) {
--
2.30.1