On 29 October 2022 19:12:39 EEST, "José Expósito" <jose.exposito89@xxxxxxxxx> wrote: >The XP-PEN Deco LW drawing tablet can be connected by USB cable or using >a USB Bluetooth dongle. When it is connected using the dongle, there >might be a small delay until the tablet is paired with the dongle. > >Fetching the device battery during this delay results in random battery >percentage values. > >Add a quirk to avoid actively querying the battery percentage and wait >for the device to report it on its own. > >Reported-by: Mia Kanashi <chad@xxxxxxxxxxxxx> >Signed-off-by: José Expósito <jose.exposito89@xxxxxxxxx> >--- > drivers/hid/hid-input.c | 6 ++++++ > 1 file changed, 6 insertions(+) > >diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c >index 859aeb07542e..d728a94c642e 100644 >--- a/drivers/hid/hid-input.c >+++ b/drivers/hid/hid-input.c >@@ -340,6 +340,7 @@ static enum power_supply_property hidinput_battery_props[] = { > #define HID_BATTERY_QUIRK_PERCENT (1 << 0) /* always reports percent */ > #define HID_BATTERY_QUIRK_FEATURE (1 << 1) /* ask for feature report */ > #define HID_BATTERY_QUIRK_IGNORE (1 << 2) /* completely ignore the battery */ >+#define HID_BATTERY_QUIRK_AVOID_QUERY (1 << 3) /* do not query the battery */ > > static const struct hid_device_id hid_battery_quirks[] = { > { HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_APPLE, >@@ -373,6 +374,8 @@ static const struct hid_device_id hid_battery_quirks[] = { > HID_BATTERY_QUIRK_IGNORE }, > { HID_USB_DEVICE(USB_VENDOR_ID_ELAN, USB_DEVICE_ID_ASUS_UX550VE_TOUCHSCREEN), > HID_BATTERY_QUIRK_IGNORE }, >+ { HID_USB_DEVICE(USB_VENDOR_ID_UGEE, USB_DEVICE_ID_UGEE_XPPEN_TABLET_DECO_L), >+ HID_BATTERY_QUIRK_AVOID_QUERY }, > { HID_I2C_DEVICE(USB_VENDOR_ID_ELAN, I2C_DEVICE_ID_HP_ENVY_X360_15), > HID_BATTERY_QUIRK_IGNORE }, > { HID_I2C_DEVICE(USB_VENDOR_ID_ELAN, I2C_DEVICE_ID_HP_ENVY_X360_15T_DR100), >@@ -554,6 +557,9 @@ static int hidinput_setup_battery(struct hid_device *dev, unsigned report_type, > dev->battery_avoid_query = report_type == HID_INPUT_REPORT && > field->physical == HID_DG_STYLUS; > >+ if (quirks & HID_BATTERY_QUIRK_AVOID_QUERY) >+ dev->battery_avoid_query = true; >+ > dev->battery = power_supply_register(&dev->dev, psy_desc, &psy_cfg); > if (IS_ERR(dev->battery)) { > error = PTR_ERR(dev->battery); I've tested this patch and now power supply status is correctly set to Unknown and capacity is set to 0 initially. Just a note that that issue occured not only with the dongle, but a cable also. It seems that tablet just doesn't respond to the query. Thank you for the work!