Commit c7b3e98e authored by Michał Kępień's avatar Michał Kępień Committed by Andy Shevchenko

platform/x86: fujitsu-laptop: Fix radio LED detection

Radio LED detection method implemented in commit 4f62568c
("fujitsu-laptop: Support radio LED") turned out to be incorrect as it
causes a radio LED to be erroneously detected on a Fujitsu Lifebook E751
which has a slide switch (and thus no radio LED).  Use bit 17 of
flags_supported (the value returned by method S000 of ACPI device
FUJ02E3) to determine whether a radio LED is present as it seems to be a
more reliable indicator, based on comparing DSDT tables of four Fujitsu
Lifebook models (E744, E751, S7110, S8420).

Fixes: 4f62568c ("fujitsu-laptop: Support radio LED")
Reported-by: default avatarHeinrich Siebmanns <harv@gmx.de>
Signed-off-by: default avatarMichał Kępień <kernel@kempniu.pl>
Tested-by: default avatarHeinrich Siebmanns <harv@gmx.de>
Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
parent 163ca800
......@@ -691,6 +691,7 @@ static enum led_brightness eco_led_get(struct led_classdev *cdev)
static int acpi_fujitsu_laptop_leds_register(struct acpi_device *device)
{
struct fujitsu_laptop *priv = acpi_driver_data(device);
struct led_classdev *led;
int result;
......@@ -724,12 +725,15 @@ static int acpi_fujitsu_laptop_leds_register(struct acpi_device *device)
}
/*
* BTNI bit 24 seems to indicate the presence of a radio toggle
* button in place of a slide switch, and all such machines appear
* to also have an RF LED. Therefore use bit 24 as an indicator
* that an RF LED is present.
* Some Fujitsu laptops have a radio toggle button in place of a slide
* switch and all such machines appear to also have an RF LED. Based on
* comparing DSDT tables of four Fujitsu Lifebook models (E744, E751,
* S7110, S8420; the first one has a radio toggle button, the other
* three have slide switches), bit 17 of flags_supported (the value
* returned by method S000 of ACPI device FUJ02E3) seems to indicate
* whether given model has a radio toggle button.
*/
if (call_fext_func(device, FUNC_BUTTONS, 0x0, 0x0, 0x0) & BIT(24)) {
if (priv->flags_supported & BIT(17)) {
led = devm_kzalloc(&device->dev, sizeof(*led), GFP_KERNEL);
if (!led)
return -ENOMEM;
......
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