[PATCH] AT91, DT, usb gadget: disable pull-up on vbus-gpio (PB16) to reduce power consumption
Bo Shen
voice.shen at atmel.com
Thu Jan 15 22:22:46 PST 2015
Hi Sylvain Rochet,
On 01/16/2015 12:00 AM, Sylvain Rochet wrote:
> There is an external resistor divider on PB16, acting like a pull-down,
> the pull-up increase power consumption and prevent the vbus detect pin
> to reach Vss voltage, ~1.5V mesured on my board, it might no even work
> if the pull-up is stronger than usual.
>
> Signed-off-by: Sylvain Rochet <sylvain.rochet at finsecur.com>
Thanks for your patch.
Acked-by: Bo Shen <voice.shen at atmel.com>
> ---
> arch/arm/boot/dts/at91sam9x5ek.dtsi | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/arch/arm/boot/dts/at91sam9x5ek.dtsi b/arch/arm/boot/dts/at91sam9x5ek.dtsi
> index 3a9f6fa..f622f96 100644
> --- a/arch/arm/boot/dts/at91sam9x5ek.dtsi
> +++ b/arch/arm/boot/dts/at91sam9x5ek.dtsi
> @@ -53,6 +53,8 @@
> };
>
> usb2: gadget at f803c000 {
> + pinctrl-names = "default";
> + pinctrl-0 = <&pinctrl_board_usb2>;
> atmel,vbus-gpio = <&pioB 16 GPIO_ACTIVE_HIGH>;
> status = "okay";
> };
> @@ -80,6 +82,13 @@
> <AT91_PIOD 14 AT91_PERIPH_GPIO AT91_PINCTRL_PULL_UP_DEGLITCH>; /* PD14 gpio CD pin pull up and deglitch */
> };
> };
> +
> + usb2 {
> + pinctrl_board_usb2: usb2-board {
> + atmel,pins =
> + <AT91_PIOB 16 AT91_PERIPH_GPIO AT91_PINCTRL_DEGLITCH>; /* PB16, no pull up and deglitch */
Nitpick:
I think comments as "PB16 gpio vbus sense, deglitch" will be better. Or
else change "pinctrl_board_usb2" to "pinctrl_usb2_vbus_sense". These
will be help the user easily to understand the function of this pin.
> + };
> + };
> };
>
> spi0: spi at f0000000 {
>
Best Regards,
Bo Shen
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