Minimum brightness is too high
Setting the minimum admisible brightness from the shell top bar or from the power settings panel, I get:
~:: cat /sys/class/backlight/intel_backlight/max_brightness
4648
~:: cat /sys/class/backlight/intel_backlight/brightness
365
which is about 8% of the range. This is too high for me. Now, inspecting the code of gsd power plugin I found the following:
backlight->brightness_max = g_udev_device_get_sysfs_attr_as_int (backlight->udev_device,
"max_brightness");
backlight->brightness_min = MAX (1, backlight->brightness_max * 0.01);
This is a bit surprising since clearly I'm not getting a 1% minimum, as shown above.
BTW, I can set lower values by writing to /sys/class/backlight/intel_backlight/brightness .