Commit 9e9c6413 authored by Hans de Goede's avatar Hans de Goede
Browse files

platform/x86: thinkpad_acpi: Don't register keyboard_lang unnecessarily 



All recent ThinkPad BIOS-es support the GSKL method used to query the
keyboard-layout used by the ECFW for the SHIFT + other-key key-press
emulation for special keys such as e.g. the '=', '(' and ')' keys
above the numpad on 15" models.

So just checking for the method is not a good indicator of the
model supporting getting/setting the keyboard_lang.

On models where this is not supported GSKL succeeds, but it returns
METHOD_ERR in the returned integer to indicate that this is not
supported on this model.

Add a check for METHOD_ERR and return -ENODEV if it is set to
avoid registering a non-working keyboard_lang sysfs-attr on models
where this is not supported.

Cc: Nitin Joshi <njoshi1@lenovo.com>
Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210125205258.135664-1-hdegoede@redhat.com
parent 64b0efa1

drivers/platform/x86/thinkpad_acpi.c

+7 −0
Original line number Diff line number Diff line
@@ -10047,6 +10047,13 @@ static int get_keyboard_lang(int *output) 
	if (!acpi_evalf(gskl_handle, &kbd_lang, NULL, "dd", 0x02000000))

		return -EIO;



	/*

	 * METHOD_ERR gets returned on devices where there are no special (e.g. '=',

	 * '(' and ')') keys which use layout dependent key-press emulation.

	 */

	if (kbd_lang & METHOD_ERR)

		return -ENODEV;



	*output = kbd_lang;



	return 0;