t@t-pc:~$  grep -r . /sys/class/backlight/*
/sys/class/backlight/radeon_bl0/type:raw
/sys/class/backlight/radeon_bl0/brightness:24
/sys/class/backlight/radeon_bl0/power/control:auto
/sys/class/backlight/radeon_bl0/power/async:disabled
/sys/class/backlight/radeon_bl0/power/runtime_enabled:disabled
/sys/class/backlight/radeon_bl0/power/runtime_active_kids:0
/sys/class/backlight/radeon_bl0/power/runtime_active_time:0
grep: /sys/class/backlight/radeon_bl0/power/autosuspend_delay_ms: Input/Output error
/sys/class/backlight/radeon_bl0/power/runtime_status:unsupported
/sys/class/backlight/radeon_bl0/power/runtime_usage:0
/sys/class/backlight/radeon_bl0/power/runtime_suspended_time:0
/sys/class/backlight/radeon_bl0/bl_power:0
/sys/class/backlight/radeon_bl0/max_brightness:255
/sys/class/backlight/radeon_bl0/actual_brightness:24
t@t-pc:~$