Commit d8e98060 authored by Aaron Armstrong Skomra's avatar Aaron Armstrong Skomra Committed by Jiri Kosina
Browse files

HID: wacom: generic: only switch the mode on devices with LEDs 



Currently, the driver will attempt to set the mode on all
devices with a center button, but some devices with a center
button lack LEDs, and attempting to set the LEDs on devices
without LEDs results in the kernel error message of the form:

"leds input8::wacom-0.1: Setting an LED's brightness failed (-32)"

This is because the generic codepath erroneously assumes that the
BUTTON_CENTER usage indicates that the device has LEDs, the
previously ignored TOUCH_RING_SETTING usage is a more accurate
indication of the existence of LEDs on the device.

Fixes: 10c55cac ("HID: wacom: generic: support LEDs")
Cc: <stable@vger.kernel.org> # v4.11+
Signed-off-by: default avatarAaron Armstrong Skomra <aaron.skomra@wacom.com>
Reviewed-by: default avatarJason Gerecke <jason.gerecke@wacom.com>
Signed-off-by: default avatarJiri Kosina <jkosina@suse.cz>
parent b4dd05de

drivers/hid/wacom_sys.c

+3 −0
Original line number Diff line number Diff line
@@ -307,6 +307,9 @@ static void wacom_feature_mapping(struct hid_device *hdev, 
	wacom_hid_usage_quirk(hdev, field, usage);



	switch (equivalent_usage) {

	case WACOM_HID_WD_TOUCH_RING_SETTING:

		wacom->generic_has_leds = true;

		break;

	case HID_DG_CONTACTMAX:

		/* leave touch_max as is if predefined */

		if (!features->touch_max) {

drivers/hid/wacom_wac.c

+0 −2
Original line number Diff line number Diff line
@@ -1906,8 +1906,6 @@ static void wacom_wac_pad_usage_mapping(struct hid_device *hdev, 
		features->device_type |= WACOM_DEVICETYPE_PAD;

		break;

	case WACOM_HID_WD_BUTTONCENTER:

		wacom->generic_has_leds = true;

		/* fall through */

	case WACOM_HID_WD_BUTTONHOME:

	case WACOM_HID_WD_BUTTONUP:

	case WACOM_HID_WD_BUTTONDOWN:

drivers/hid/wacom_wac.h

+1 −0
Original line number Diff line number Diff line
@@ -145,6 +145,7 @@ 
#define WACOM_HID_WD_OFFSETBOTTOM       (WACOM_HID_UP_WACOMDIGITIZER | 0x0d33)

#define WACOM_HID_WD_DATAMODE           (WACOM_HID_UP_WACOMDIGITIZER | 0x1002)

#define WACOM_HID_WD_DIGITIZERINFO      (WACOM_HID_UP_WACOMDIGITIZER | 0x1013)

#define WACOM_HID_WD_TOUCH_RING_SETTING (WACOM_HID_UP_WACOMDIGITIZER | 0x1032)

#define WACOM_HID_UP_G9                 0xff090000

#define WACOM_HID_G9_PEN                (WACOM_HID_UP_G9 | 0x02)

#define WACOM_HID_G9_TOUCHSCREEN        (WACOM_HID_UP_G9 | 0x11)

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