2008-04-02 21:12:24     gpio-keys

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2008-04-02 21:12:24     gpio-keys

Jonathan Kotta (UNITED STATES)

Message: 53574    I have a bf548-ezkit rev 1.6.  I'm having trouble with gpio-keys.  I've used them before on another architecture, and read the wiki page for blackfin gpio-keys.  My PB switches (SW5) are all on.


The driver has apparently has trouble registering the irqs.  There are no errors (request_irq() returns 0), but no interrupts are generated.


root:/proc> cat /proc/interrupts | grep gpio-keys

127:          0   gpio-keys: BTN0

128:          0   gpio-keys: BTN1

129:          0   gpio-keys: BTN2

130:          0   gpio-keys: BTN3







2008-04-02 23:34:36     Re: gpio-keys


Message: 53576    What is the kernel version you are using? I tested the input/keyboard/gpio-keys.c driver on r1.3  548EZkit, with 2008r1 branch, it works well.




2008-04-03 11:28:52     Re: gpio-keys

Jonathan Kotta (UNITED STATES)

Message: 53607    I'm using rev 4535 (Apr. 2) from subversion.  Same thing happens with svn 4396 (Mar. 1).  I'll try the 2008r1.


I forgot to mention, there are a bunch of error messages at boot up saying that GPIO 24-27 are being used by gpio-keys.  I think this is from the generic GPIO driver, right after gpio-keys in ezkit.c.  I am assuming this is not a problem because a) it says gpio-keys already has the GPIO and b) the generic GPIO driver doesn't set up interrupts (AFAIK).


bfin-gpio: GPIO 27 is already reserved by gpio-keys: BTN3 !

Hardware Trace:

   0 Target : <0x000044fc> { _dump_stack + 0x0 }

     Source : <0x000056f0> { _gpio_request + 0x108 }

   1 Target : <0x000056f0> { _gpio_request + 0x108 }

     Source : <0x0000d706> { _printk + 0x16 }






2008-04-03 11:38:24     Re: gpio-keys

Michael Hennerich (GERMANY)

Message: 53608    So You are using trunk ... This is a know issue


See here:

[#3919] Allow concurrent use of GPIO and GPIO IRQ




For now please use 2008R1






2008-04-03 15:30:30     Re: gpio-keys

Jonathan Kotta (UNITED STATES)

Message: 53618    OK, it works fine on 2008r1.  Thanks.




2008-04-03 17:52:28     Re: gpio-keys

Jonathan Kotta (UNITED STATES)

Message: 53624    I want to use simple-gpio, which is not in the 2008r1 kernel.  So I backported it.  Patch is attached in case anyone else wants it.