Linux Userspace GPIO Interrupts using sysfs
The "edge" file only exists if that GPIO pin can be configured as a an interrupt generting pin. See: http://www.mjmwired.net/kernel/Documentation/gpio.txt#634.
Since you don't see it, it means the driver and possibly the hardware do not support using that GPIO pin for interrupt source.
lgm42
Updated on June 04, 2022Comments
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lgm42 almost 2 years
I would like to use interrupts with GPIO on userspace using sysfs. I use these commands :
[root@at91]:gpio109 > echo 109 > export [root@at91]:gpio109 > cd gpio109/ [root@at91]:gpio109 > ll -rw-r--r-- 1 root 0 4096 Jan 1 00:17 direction drwxr-xr-x 2 root 0 0 Jan 1 00:17 power lrwxrwxrwx 1 root 0 0 Jan 1 00:17 subsystem -> ../../gpio -rw-r--r-- 1 root 0 4096 Jan 1 00:17 uevent -rw-r--r-- 1 root 0 4096 Jan 1 00:17 value
The gpio works well but I can't use interrupts. I read everywhere i must have an edge file to poll this file. But on my system this file doesn't exist. I made a lot of tries to find a solution but remain unsuccessfull.
My target is an AT91SAM9263 on linux kernel 2.6.30.
At the boot of my board I got this message on interrupts :
AT91: 160 gpio irqs in 5 banks
which show that the function
at91_gpio_irq_setup()
is well executed.Have you any idea ?
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Tim Post over 12 yearsNice edit to the question, and nice answer :) I read this when it was posted, and didn't notice the version number.