From ef45e08141f85d37eb548dd6bf753f1b9534a1e4 Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Tue, 14 Oct 2025 21:28:44 -0700 Subject: [PATCH] HID: hid-input: only ignore 0 battery events for digitizers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit 0187c08058da3e7f11b356ac27e0c427d36f33f2 ] Commit 581c4484769e ("HID: input: map digitizer battery usage") added handling of battery events for digitizers (typically for batteries presented in stylii). Digitizers typically report correct battery levels only when stylus is actively touching the surface, and in other cases they may report battery level of 0. To avoid confusing consumers of the battery information the code was added to filer out reports with 0 battery levels. However there exist other kinds of devices that may legitimately report 0 battery levels. Fix this by filtering out 0-level reports only for digitizer usages, and continue reporting them for other kinds of devices (Smart Batteries, etc). Reported-by: 卢国宏 Fixes: 581c4484769e ("HID: input: map digitizer battery usage") Signed-off-by: Dmitry Torokhov Signed-off-by: Jiri Kosina Signed-off-by: Sasha Levin --- drivers/hid/hid-input.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c index f5c217ac4bfa..f073d5621050 100644 --- a/drivers/hid/hid-input.c +++ b/drivers/hid/hid-input.c @@ -622,7 +622,10 @@ static void hidinput_update_battery(struct hid_device *dev, unsigned int usage, return; } - if (value == 0 || value < dev->battery_min || value > dev->battery_max) + if ((usage & HID_USAGE_PAGE) == HID_UP_DIGITIZER && value == 0) + return; + + if (value < dev->battery_min || value > dev->battery_max) return; capacity = hidinput_scale_battery_capacity(dev, value);