2008-02-01 16:16:34     API for GPIO Wakeups

Document created by Aaronwu Employee on Aug 9, 2013
Version 1Show Document
  • View in full screen mode

2008-02-01 16:16:34     API for GPIO Wakeups

Christopher Harrsen (UNITED STATES)

Message: 50582   

 

I would like to use the API for GPIO wakeups. This is a kernel space API. Does this mean I have to compile my application to run in Kernel space. How do I call these functions from user space?

 

 

 

 

QuoteReplyEditDelete

 

 

2008-02-01 16:49:18     Re: API for GPIO Wakeups

Robin Getz (UNITED STATES)

Message: 50585    Chris:

 

Just to understand the terminology: _in kernel_ interfaces ( interface between drivers and kernel functions - the "kernel API") are not the kernel to userspace interfaces (the "syscall interface").

 

You can not use a kernel API from userspace.

You can not run an userspace application in the kernel.

 

The kernel GPIO API is at:

http://docs.blackfin.uclinux.org/doku.php?id=gpio

 

But, this has nothing to do with userspace. What you need to do is write a GPIO driver, that exposes this to userspace.

 

Since this is pretty common - we added a GPIO driver:

http://docs.blackfin.uclinux.org/doku.php?id=sample_gpio_driver

 

To usethat  GPIO from userspace:

http://docs.blackfin.uclinux.org/doku.php?id=sample_gpio_driver#test_the_driver

 

and have a look at the example code.

 

-Robin

QuoteReplyEditDelete

 

 

2008-02-05 15:47:37     Re: API for GPIO Wakeups

Christopher Harrsen (UNITED STATES)

Message: 50712   

 

Robin:

 

Do you have user space code examples of using ioctls' to configure specific GPIOs as interrupts? Also, which ioctl calls (or system calls) can I use to put the processor into sleep mode?

 

Thanks,

 

Chris

QuoteReplyEditDelete

 

 

2008-02-05 17:42:35     Re: API for GPIO Wakeups

Robin Getz (UNITED STATES)

Message: 50716    Chris:

 

At the moment - it looks like the docs do not reflect the existing code - it might take a day or two to fix up.

 

I will let you know as soon as it is done.

-Robin

QuoteReplyEditDelete

 

 

2008-02-05 20:09:54     Re: API for GPIO Wakeups

Mike Frysinger (UNITED STATES)

Message: 50720    you do not use ioctl's to create interrupt handlers.  if you want to use a GPIO as an interrupt source, you currently need to write a kernel driver to do so.

 

to put the processor to sleep, you use the sysfs interface ... this part should be in the power management document in the wiki.

QuoteReplyEditDelete

 

 

2009-01-14 02:26:49     Re: API for GPIO Wakeups

Larry Fiery (UNITED STATES)

Message: 67902   

 

Robin:

 

The links below say "you've followed a link to a topic that doesn't exist yet.":

 

http://docs.blackfin.uclinux.org/doku.php?id=sample_gpio_driver

 

http://docs.blackfin.uclinux.org/doku.php?id=sample_gpio_driver#test_the_driver

 

-Larry

QuoteReplyEditDelete

 

 

2009-01-14 06:17:47     Re: API for GPIO Wakeups

Mike Frysinger (UNITED STATES)

Message: 67939   

 

the wiki does have a search function ...

QuoteReplyEditDelete

 

 

2009-01-14 12:01:32     Re: API for GPIO Wakeups

Robin Getz (UNITED STATES)

Message: 67945   

 

Larry:

 

We are moving some of the pages around -- sorry for the confusion - the page names should be close - there may be a chapter name inbetween.

 

-Robin

Attachments

    Outcomes