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    SubjectRe: problems with GPIO
    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()?

    g.
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