Messages in this thread | | | From | Grant Likely <> | Date | Wed, 2 Mar 2011 23:24:14 -0700 | Subject | Re: problems with GPIO |
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On Thu, Feb 17, 2011 at 9:21 PM, Murali K. Vemuri <vemuri.muralikrishna@gmail.com> wrote: > Hi There, > > I am rather a novice with linux kernel and I have this problem. > My board is OMAP 3530 based and I use GPIO 21 to detect an external > device plug-in. > Now, when the board is just booted (after a complete power disconnect > ), the GPIO is high, and when I plug in my external device, the GPIO > goes low, and I am able to detect it. > However, I see the voltage level still low after I remove the external > plug-in, and any further plug-ins, remain un-detected. > My H/W engineers say it is some config I am missing in Kernel. > can someone point me? > > my code snippet is like: > > omap_mux_init_gpio(MY_GPIO, OMAP_PIN_INPUT_PULLDOWN ); > gpio_request(MY_GPIO,"CABLE IN"); > gpio_direction_input(MY_GPIO); > gpio_set_value(MY_GPIO,1);
It depends on the gpio controller driver, but gpio_set_value() is very likely switching the GPIO pin from input to output. Why are you calling gpio_set_value()?
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