From mboxrd@z Thu Jan 1 00:00:00 1970 From: ksashtekar@gmail.com (Kaustubh Ashtekar) Date: Fri, 11 Mar 2011 16:38:29 +0530 Subject: SPI over GPIO In-Reply-To: <344296.43554.qm@web56301.mail.re3.yahoo.com> References: <344296.43554.qm@web56301.mail.re3.yahoo.com> Message-ID: To: kernelnewbies@lists.kernelnewbies.org List-Id: kernelnewbies.lists.kernelnewbies.org Please paste the full log of what you typed on the console and also paste output of: strace On Fri, Mar 11, 2011 at 4:04 PM, Alexandru Caramida wrote: > Hello everyone, > I am trying to emulate an SPI interface using four GPIO pins. This is a > desktop computer with linux 2.6.28 kernel. > The problem is I don't know if the pins are working. I read that if I have > the sysfs support for the kernel (which I do :D) all I have to do > is enable the respectiv pin using > echo N > /sys/class/gpio/export > And I would get a gpioN directory > But I always get: "write error : invalid argument." > Is there some other option i need to enable first? The people I am working > with assured me that these pins are not used by any other device and they > haven't found anything to suggest that they were turned off manualy. > Please help, > > > > _______________________________________________ > Kernelnewbies mailing list > Kernelnewbies at kernelnewbies.org > http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies > >