Created attachment 239221 [details] Output of 'sudo lshw' from Asus e200ha Laptop I have an Asus e200ha laptop and the FN keys are unable to control the LCD backlight brightness. FN+5 should decrease brightness FN+6 should increase brightness If I execute acpi_listen and then press the above keys no events are generated. Running evtest on the device "/dev/input/event6: Asus WMI hotkeys" results in no events when the FN keys are pressed. Output from sudo lshw is attached.
As a matter of reference FN+10, FN+11 and FN+12 do all generate events when using acpi_listen. These keys are mute, vol down and vol up. acpi_listen output when using the above keys: gavin@gavin-E200HA:~$ acpi_listen button/mute MUTE 00000080 00000000 K button/volumedown VOLDN 00000080 00000000 K button/volumeup VOLUP 00000080 00000000 K All other FN keys generate no output. The following is a list of FN keys that are not working: FN+1 Sleep FN+2 Airplane Mode FN+5 Decrease brightness FN+6 Increase brightness FN+7 (Erm .. icon is a box with and X in the middle) Not sure. FN+8 Switch Displays FN+9 Disable/enable touchpad Please let me know if I can provide further information.
please attach the output of "cat /proc/interrupts" and "grep . /sys/firmware/acpi/interrupts/*" both before and after pressing the brightness up/down hotkeys.
Created attachment 239861 [details] before pressing - cat /proc/inturrupts
Created attachment 239871 [details] before pressing - grep . /sys/firmware/acpi/interrupts/*
Created attachment 239881 [details] after pressing - cat /proc/interrupts
Created attachment 239891 [details] after pressing - grep . /sys/firmware/acpi/interrupts/*
By comparing /proc/interrupts, we can see that there are several differences after pressing the hotkeys. - 32: 1521 1805 0 0 IO-APIC 32-fasteoi 808622C1:00 + 32: 1521 4249 0 0 IO-APIC 32-fasteoi 808622C1:00 this is the I2C controller, code is drivers/i2c/busses/i2c-designware-platdrv.c - 34: 269 112780 0 0 IO-APIC 34-fasteoi 808622C1:02 + 34: 269 550515 0 0 IO-APIC 34-fasteoi 808622C1:02 this is the I2C controller, code is drivers/i2c/busses/i2c-designware-platdrv.c - 45: 12429 48918 0 0 IO-APIC 45-fasteoi mmc0 + 45: 12429 58690 0 0 IO-APIC 45-fasteoi mmc0 this is the mmc storage, and it has nothing to do with the hotkey - 166: 159 0 0 0 chv-gpio 51 PDEC3393:00 + 166: 400 0 0 0 chv-gpio 51 PDEC3393:00 this is the gpio controller, code is drivers/pinctrl/intel/pinctrl-cherryview.c - 182: 3375 0 0 0 chv-gpio 11 ELAN0100:00 + 182: 16695 0 0 0 chv-gpio 11 ELAN0100:00 this is the gpio controller, code is drivers/pinctrl/intel/pinctrl-cherryview.c
First of all, I don't think this is an ACPI bug as there is no ACPI interrupts when pressing these hotkeys. Usually, this is a feature gap that some platform specific drivers fail to catch these events and expose to userspace. Eventually, some guy may introduce this feature to Linux by reverse engineering or something else, but I don't know when. And for this issue, the best way is to raise it to Asus to provide Linux support for this. Bug closed.