HID: hid-input: add Surface Go battery quirk

The Elantech touchscreen/digitizer in the Surface Go mistakenly reports
having a battery. This results in a low battery message every time you
try to use the pen.

This patch adds a quirk to ignore the non-existent battery and
gets rid of the false low battery messages.

Signed-off-by: Zoltan Tamas Vajda <redacted>
---
 drivers/hid/hid-ids.h   | 1 +
 drivers/hid/hid-input.c | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index b84a0a11e05b..63ca5959dc67 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h

@@ -396,6 +396,7 @@
 #define USB_DEVICE_ID_HP_X2_10_COVER	0x0755
 #define I2C_DEVICE_ID_HP_SPECTRE_X360_15	0x2817
 #define USB_DEVICE_ID_ASUS_UX550_TOUCHSCREEN	0x2706
+#define I2C_DEVICE_ID_SURFACE_GO_TOUCHSCREEN	0x261A
 
 #define USB_VENDOR_ID_ELECOM		0x056e
 #define USB_DEVICE_ID_ELECOM_BM084	0x0061

diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
index abbfa91e73e4..3e39aeafca91 100644
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c

@@ -326,6 +326,8 @@ static const struct hid_device_id hid_battery_quirks[] = {
 	  HID_BATTERY_QUIRK_IGNORE },
 	{ HID_I2C_DEVICE(USB_VENDOR_ID_ELAN, I2C_DEVICE_ID_HP_SPECTRE_X360_15),
 	  HID_BATTERY_QUIRK_IGNORE },
+	{ HID_I2C_DEVICE(USB_VENDOR_ID_ELAN, I2C_DEVICE_ID_SURFACE_GO_TOUCHSCREEN),
+	  HID_BATTERY_QUIRK_IGNORE },
 	{}
 };
 

-- 
2.30.2

On Thu, 3 Jun 2021, Zoltan Tamas Vajda wrote:

The Elantech touchscreen/digitizer in the Surface Go mistakenly reports
having a battery. This results in a low battery message every time you
try to use the pen.

This patch adds a quirk to ignore the non-existent battery and
gets rid of the false low battery messages.

Signed-off-by: Zoltan Tamas Vajda <redacted>

Applied, thanks.

-- 
Jiri Kosina
SUSE Labs