From 0152b29c89650654abf4f0e96bbf2566b85ae55d Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Thu, 10 Aug 2017 12:47:56 -0700 Subject: [PATCH] HID: input: throttle battery uevents The power_supply subsystem tends to emit uevent every time power_supply_changed() is called, so we should call this API only when battery strength reported by the device is actually different from the previous readings, otherwise we'll drown the system in uevents. Fixes: 581c4484769e ("HID: input: map digitizer battery usage") Signed-off-by: Dmitry Torokhov Signed-off-by: Jiri Kosina --- drivers/hid/hid-input.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c index 27d8442b017d..199f6a01fc62 100644 --- a/drivers/hid/hid-input.c +++ b/drivers/hid/hid-input.c @@ -520,15 +520,21 @@ static void hidinput_cleanup_battery(struct hid_device *dev) static void hidinput_update_battery(struct hid_device *dev, int value) { + int capacity; + if (!dev->battery) return; if (value == 0 || value < dev->battery_min || value > dev->battery_max) return; - dev->battery_capacity = hidinput_scale_battery_capacity(dev, value); - dev->battery_reported = true; - power_supply_changed(dev->battery); + capacity = hidinput_scale_battery_capacity(dev, value); + + if (!dev->battery_reported || capacity != dev->battery_capacity) { + dev->battery_capacity = capacity; + dev->battery_reported = true; + power_supply_changed(dev->battery); + } } #else /* !CONFIG_HID_BATTERY_STRENGTH */ static int hidinput_setup_battery(struct hid_device *dev, unsigned report_type, -- 2.34.1