On Sun, Jan 15, 2017 at 4:09 PM, Richard Ryniker <ryniker(a)alum.mit.edu> wrote:
Additional problem on Raspberry Pi (model 3): there is no:
/sys/class/gpio
The sysfs interface is deprecated [1] so I had disabled it on rawhide.
I didn't intend on this change coming back into the stable releases
but I must have screwed something up. It'll be back in F-25 with the
4.9.4 kernel which should be built today.
This does exist with the 4.8.15-300 kernel, but it has problems:
[root@RPi3-1 gpiochip970]# echo 993 >/sys/class/gpio/export
[root@RPi3-1 gpiochip970]# echo 1 > /sys/class/gpio/gpio993/value
bash: echo: write error: Operation not permitted
[root@RPi3-1 gpiochip970]# ls -l /sys/class/gpio/gpio993
lrwxrwxrwx. 1 root root 0 Jan 15 10:24 /sys/class/gpio/gpio993 ->
../../devices/platform/soc/3f200000.gpio/gpiochip0/gpio/gpio993
[root@RPi3-1 gpiochip970]# ls -l
/sys/devices/platform/soc/3f200000.gpio/gpiochip0/gpio/gpio993
total 0
-rw-r--r--. 1 root root 4096 Jan 15 10:24 active_low
lrwxrwxrwx. 1 root root 0 Jan 15 10:24 device -> ../../../gpiochip0
-rw-r--r--. 1 root root 4096 Jan 15 10:24 direction
-rw-r--r--. 1 root root 4096 Jan 15 10:24 edge
drwxr-xr-x. 2 root root 0 Jan 15 10:24 power
lrwxrwxrwx. 1 root root 0 Jan 15 10:24 subsystem ->
../../../../../../../class/gpio
-rw-r--r--. 1 root root 4096 Jan 15 10:24 uevent
-rw-rw-rw-. 1 root root 4096 Jan 15 10:27 value
[root@RPi3-1 gpiochip970]# echo 1 >
/sys/devices/platform/soc/3f200000.gpio/gpiochip0/gpio/gpio993/value
bash: echo: write error: Operation not permitted
[root@RPi3-1 gpiochip970]#
[1]
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id...