Support screen brightness adjustment button, the KEY_BRIGHTNESS_CYCLE EV_KEY

Submitted by jia..@..sm.com

Assigned to xkb..@..bat.ru

Description

The Acer Veriton Z4660G/Z4860G/Z6860G series AIO desktops have a brightness button in the bottom, but pressing the button does not work on Linux. According to ODM's description, a control application will popup for brightness adjustment on Windows, if the button is pressed. I have checked it with evtest:

sudo evtest No device specified, trying to scan all of /dev/input/event* Available devices: /dev/input/event0: Sleep Button /dev/input/event1: Power Button /dev/input/event2: Power Button /dev/input/event3: Video Bus /dev/input/event4: USB Optical Mouse /dev/input/event5: Wired USB Keyboard /dev/input/event6: Wired USB Keyboard System Control /dev/input/event7: Wired USB Keyboard Consumer Control /dev/input/event8: HDA Intel PCH Front Mic /dev/input/event9: HDA Intel PCH Front Headphone /dev/input/event10: HDA Intel PCH HDMI/DP,pcm=3 /dev/input/event11: HDA Intel PCH HDMI/DP,pcm=7 /dev/input/event12: HDA Intel PCH HDMI/DP,pcm=8 /dev/input/event13: HDA Intel PCH HDMI/DP,pcm=9 /dev/input/event14: HDA Intel PCH HDMI/DP,pcm=10 /dev/input/event15: USB2.0 FHD Camera: USB2.0 FHD C Select the device event number [0-15]: 3 Input driver version is 1.0.1 Input device ID: bus 0x19 vendor 0x0 product 0x6 version 0x0 Input device name: "Video Bus" Supported events: Event type 0 (EV_SYN) Event type 1 (EV_KEY) Event code 224 (KEY_BRIGHTNESSDOWN) Event code 225 (KEY_BRIGHTNESSUP) Event code 227 (KEY_SWITCHVIDEOMODE) Event code 241 (KEY_VIDEO_NEXT) Event code 242 (KEY_VIDEO_PREV) Event code 243 (KEY_BRIGHTNESS_CYCLE) Event code 244 (KEY_BRIGHTNESS_ZERO) Event code 245 (KEY_DISPLAY_OFF) Properties: Testing ... (interrupt to exit) Event: time 1542615014.263931, type 1 (EV_KEY), code 243 (KEY_BRIGHTNESS_CYCLE), value 1 Event: time 1542615014.263931, -------------- SYN_REPORT ------------ Event: time 1542615014.263939, type 1 (EV_KEY), code 243 (KEY_BRIGHTNESS_CYCLE), value 0 Event: time 1542615014.263939, -------------- SYN_REPORT ------------ Event: time 1542615015.380922, type 1 (EV_KEY), code 243 (KEY_BRIGHTNESS_CYCLE), value 1 Event: time 1542615015.380922, -------------- SYN_REPORT ------------ Event: time 1542615015.380930, type 1 (EV_KEY), code 243 (KEY_BRIGHTNESS_CYCLE), value 0

When the button is pressed, the code 243 (KEY_BRIGHTNESS_CYCLE) is sent. I found there are codes for screen brightness "StepUp" and "StepDown". However, it seems no related code for "Brightness Cycle" (something like that) in g-s-d now.