Bug#810894: src:linux: GPIO probe failure on Linkstation LS-WXL/WSXL

[Roger Shimizu <rogershimizu@gmail.com>]

Dear Uwe,

On Thu, Jan 14, 2016 at 11:08 PM, Uwe Kleine-König
<uwe+debian@kleine-koenig.org> wrote:
>>>> I need to run the following command to enable USB port on Linkstation
>>>> LS-WXL/WSXL (armel/kirkwood with DTS [0] ):
>>>>   echo 37 >/sys/class/gpio/export
>>>>   echo out > /sys/class/gpio/gpio37/direction
>>>>   echo 1 > /sys/class/gpio/gpio37/value
>
> Can you post the contents of /sys/kernel/debug/gpio when the broken
> kernel is running?

Thanks for the debugging tool!
It seems there's clue ...

Here's the log for working & non-working kernel:

# uname -a
Linux LS-WXL 4.2.0-0.bpo.1-kirkwood #1 Debian 4.2.6-3~bpo8+2
(2015-12-14) armv5tel GNU/Linux
# mount -t debugfs none /sys/kernel/debug
# cat  /sys/kernel/debug/gpio
GPIOs 0-31, platform/f1010100.gpio, f1010100.gpio:
 gpio-28  (HDD0 Power          ) out hi
 gpio-29  (HDD1 Power          ) out hi

GPIOs 32-49, platform/f1010140.gpio, f1010140.gpio:
 gpio-34  (?                   ) out hi
 gpio-35  (?                   ) out hi
 gpio-37  (?                   ) out lo
 gpio-38  (?                   ) out hi
 gpio-40  (?                   ) out hi

# uname -a
Linux LS-WXL 3.16.0-4-kirkwood #1 Debian 3.16.7-ckt7-1 (2015-03-01)
armv5tel GNU/Linux
# mount -t debugfs none /sys/kernel/debug
# cat  /sys/kernel/debug/gpio
GPIOs 0-31, platform/f1010100.gpio, f1010100.gpio:
 gpio-28  (HDD0 Power          ) out hi
 gpio-29  (HDD1 Power          ) out hi

GPIOs 32-49, platform/f1010140.gpio, f1010140.gpio:
 gpio-34  (lswxl:red:hdderr0   ) out hi
 gpio-35  (lswxl:red:hdderr1   ) out hi
 gpio-37  (lswxl:red:func      ) out lo
 gpio-38  (lswxl:amber:info    ) out hi
 gpio-40  (lswxl:blue:power    ) out hi

Cheers,
Roger