Hello Bo,
On Mon, Feb 09, 2015 at 05:02:52PM +0800, Bo Shen wrote:
> Enable usb device port on at91sam9n12ek board.
>
> Signed-off-by: Bo Shen <[email protected]>
> ---
>
> arch/arm/boot/dts/at91sam9n12ek.dts | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/arch/arm/boot/dts/at91sam9n12ek.dts
> b/arch/arm/boot/dts/at91sam9n12ek.dts
> index 13bb24e..3e572e5 100644
> --- a/arch/arm/boot/dts/at91sam9n12ek.dts
> +++ b/arch/arm/boot/dts/at91sam9n12ek.dts
> @@ -120,6 +120,11 @@
> };
> };
>
> + usb1: gadget@f803c000 {
> + atmel,vbus-gpio = <&pioB 16 GPIO_ACTIVE_HIGH>;
> + status = "okay";
> + };
> +
There is an external resistor divider on PB16, acting like a pull-down
(R22+R23). PB16 reset state is input, pull-up, schmitt trigger, you need
to disable the pull-up in pinctrl this way:
usb1: gadget@f803c000 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_board_usb1>;
…
}
pinctrl … {
usb1 {
pinctrl_board_usb1: usb1-board {
atmel,pins = <AT91_PIOB 16 AT91_PERIPH_GPIO
AT91_PINCTRL_DEGLITCH>; /* PB16, no pull up and deglitch */
};
};
};
Sylvain
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