On Mon, Nov 25, 2013 at 7:55 AM, Roger Quadros <rogerq@xxxxxx> wrote:
> Beagle (rev. C4) and Beagle-XM (all revs) need VAUX2 1.8V supply
> for the USB PHY.
>
> As the generic PHY driver can't handle more than one supply
> at the moment, we configure this supply to be always on.
> This will cause a very small power impact if the USB host subsystem
> is not in use, about 76.86 micro-W + LDO power.
>
> Older Beagle boards (prior to C4) don't have VAUX2 connected anywhere,
> so there won't be any functional impact on those boards other than
> some additional LDO power consumption.
>
> Reported-by: Nishanth Menon <nm@xxxxxx>
> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
Tested-by: Nishanth Menon <nm@xxxxxx>
I might suggest though that the better alternative might be to get phy
driver to handle multiple regulators considering that DT is supposed
to represent the h/w topology.
> ---
> arch/arm/boot/dts/omap3-beagle-xm.dts | 8 ++++++++
> arch/arm/boot/dts/omap3-beagle.dts | 8 ++++++++
> 2 files changed, 16 insertions(+)
>
> diff --git a/arch/arm/boot/dts/omap3-beagle-xm.dts b/arch/arm/boot/dts/omap3-beagle-xm.dts
> index 31a632f..b39918e 100644
> --- a/arch/arm/boot/dts/omap3-beagle-xm.dts
> +++ b/arch/arm/boot/dts/omap3-beagle-xm.dts
> @@ -215,3 +215,11 @@
> &usbhsehci {
> phys = <0 &hsusb2_phy>;
> };
> +
> +&vaux2 {
> + regulator-name = "usb_1v8";
> + regulator-min-microvolt = <1800000>;
> + regulator-max-microvolt = <1800000>;
> + regulator-always-on;
> +};
> +
> diff --git a/arch/arm/boot/dts/omap3-beagle.dts b/arch/arm/boot/dts/omap3-beagle.dts
> index fa532aa..9764556 100644
> --- a/arch/arm/boot/dts/omap3-beagle.dts
> +++ b/arch/arm/boot/dts/omap3-beagle.dts
> @@ -178,3 +178,11 @@
> mode = <3>;
> power = <50>;
> };
> +
> +&vaux2 {
> + regulator-name = "vdd_ehci";
> + regulator-min-microvolt = <1800000>;
> + regulator-max-microvolt = <1800000>;
> + regulator-always-on;
> +};
> +
> --
> 1.8.3.2
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
