firmware-utiles: add *.attr for GPIO symbolic links
To recognize the polarity of each GPIO, we need to expose the information from
chromeos_acpi interface.
BUG=chrome-os-partner:1940
TEST=(on mario, BIOS ver = G5) gpio_setup; cd /home/gpio; ls -l
# complete output: (output_header[1-7] is stripped)
# debug_header_0 -> /sys/class/gpio/gpio201/value
# debug_header_0.attr -> /sys/bus/platform/devices/chromeos_acpi/GPIO.3/GPIO.1
# developer_switch -> /sys/class/gpio/gpio193/value
# developer_switch.attr -> /sys/bus/platform/devices/chromeos_acpi/GPIO.1/GPIO.1
# recovery_button -> /sys/class/gpio/gpio230/value
# recovery_button.attr -> /sys/bus/platform/devices/chromeos_acpi/GPIO.0/GPIO.1
# write_protect -> /sys/class/gpio/gpio226/value
# write_protect.attr -> /sys/bus/platform/devices/chromeos_acpi/GPIO.2/GPIO.1
for X in *.attr; do echo $X - $(cat $X); done
# debug_header_0.attr - 0
# developer_switch.attr - 1
# recovery_button.attr - 0
# write_protect.attr - 0 (this should be 1 in new BIOS)
Change-Id: Ib42b4662c4369112a8f4fb69989d62f2d1b76590
Review URL: http://codereview.chromium.org/6324005
1 file changed
