2009-03-04 19:27:59     gpio-keys no /dev created

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2009-03-04 19:27:59     gpio-keys no /dev created

Adam Dershowitz (UNITED STATES)

Message: 70388   


I am trying to use gpio-keys on a bf527 ezkit.


I have tried it both as a module and in the kernel.  In each case I get the expected message in my log:


Mar 14 04:18:06 blackfin user.notice kernel: bfin-gpio: GPIO 16 is already reserved by gpio-keys: BTN0! (Documentation/blackfin/bfin-gpio-notes.txt)

Mar 14 04:18:06 blackfin user.info kernel: input: gpio-keys as /devices/platform/gpio-keys.0/input/input0



and here:


>grep gpio proc/interrupts

87:          0      GPIO  gpio-keys: BTN0



>grep 16 /proc/gpio

GPIO_16:     gpio-irq87 *         GPIO INPUT



Yet there is no /dev created that I can use.  For example:


root:/>event_test /dev/input0

event_test: No such file or directory

root:/> ls /dev/inpu*

ls: /dev/inpu*: No such file or directory


Shouldn't gpio-keys be creating:  /dev/input0  ?  Do I have to do something else to actually use gpio-keys that I am missing?  Is the kernel message above "input: gpio-keys as /devices/platform/gpio-keys.0/input/input0" actually an error and it should instead be /dev/input/input0?  If so, is there a bug in gpio-keys?











2009-03-04 19:41:42     Re: gpio-keys no /dev created

Mike Frysinger (UNITED STATES)

Message: 70389   


the path shown in the log is the *sysfs* path, not the */dev* path


you have to enable the event dev interface in order for device nodes to show up.  then they would be under /dev/input/, not in the top level /dev/ dir.






2009-03-04 21:02:05     Re: gpio-keys no /dev created

Adam Dershowitz (UNITED STATES)

Message: 70391   


Thank you.  I just looked at  docs.blackfin.uclinux.org/doku.php?id=linux-kernel:drivers:gpio-keys and did just miss that setting.