Re: [PATCH 1/3] platform/x86/pcengines-apuv2: add mpcie reset gpio export

From: Florian Eckert
Date: Mon Jul 15 2019 - 10:39:04 EST



On APUx we have also mpcie2/mpcie3 reset pins. To make it possible to reset
the ports from the userspace, add the definition to this platform
device. The gpio can then be exported by the legancy gpio subsystem to
toggle the mpcie reset pin.


Just tested your patch on an apu3. The driver itself seems to work,
but the pins don't seem to actually do anything.

How exactly did you test it ? Do you have some test case ?

I plugged in a mpcie usb modem.
In my test case it was a EC25 from Quectel in mpcie2 port.
After that I did a reboot and exported the gpio via "/sys/class/gpio"
Then I executed the command "echo 0 > /sys/class/gpio/<name>/value" and "echo 1 > /sys/class/gpio/<name>/value".
Then I have seen the log message in the kernel that the device did an unregistration/registration
.
-- Florian