[Linux-stm32] STM32MP151A sysfs

[Kegl Rohit]

Hello!

I could notice following issue with kernel version 5.10.61:
Exporting GPIO PB12 and PD12 via sysfs triggers a kernel ERROR.
After the error happend the gpio still got exported and seem to function.

Both Pins are unclaimed:
grep -e PB12 -e PD12
/sys/kernel/debug/pinctrl/soc\:pin-controller at 50002000/pinmux-pins
pin 28 (PB12): UNCLAIMED
pin 60 (PD12): UNCLAIMED

root at dev:/sys/class/gpio# echo 60 > export
root at dev:/sys/class/gpio# echo 28 > export
[   30.467370] stm32mp157-pinctrl soc:pin-controller at 50002000: irq
line 12 already requested.

The order does not matter:
root at dev:/sys/class/gpio# echo 60 > export
root at dev:/sys/class/gpio# echo 28 > export
[   20.768493] stm32mp157-pinctrl soc:pin-controller at 50002000: irq
line 12 already requested.

This is the dev_err code part:
https://github.com/STMicroelectronics/linux/commit/8eb2dfee9fb1277f635ce369ef8669df0ec421bc#diff-549d83503a258940ffa6617dbbf4859d463fcac94f376b45b1744d243ffe9b16R381

Seems that gpio sysfs requests an IRQ every time and there is some
shared IRQ limitation which is not implemented / handled yet.

Can someone reproduce this? Maybe it is only a usage / kernel /
devicetree setup error by me...
Or is this a STM32MP1 limitation? gpio sysfs bug with STM32MP1? ...


Thanks in advance.