PATH[1/3] ARM: axp20x_usb_power.c add device tree configuration options for REG 30H: VBUS-IPSOUT

[Lee Jones]

What on earth are all these emails you're sending to the list?

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 Documentation/HOWTO 
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The last one being the most prevalent in this case.

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email your patches out `git send-email`, then you'll be most of the
way there.

> The AXP20X chips have a configuration register "REG 30H: VBUS-IPSOUT Power 
> Path Management" that provide USB power supply protection.
> The current axp20x_usb_power.c provides support only for reading those 
> values.
> 
> From the datasheet:
> In order not to affect the USB communication, VBUS is always working under 
> Voltage-Limit mode by default. In this mode, AXP209 ensures that VBUS 
> voltage remains above a configurable reference voltage VHOLD which can meet 
> the USB specification. The default VHOLD is 4.4V, adjustable in Reg30H 
> [5:3] register. If the system has limit on current obtained from USB VBUS, 
> a current-limit mode is provided (See REG30H[1] register), with 
> 900mA/500mA/100mA (Reg30H [0]) selectable.
> 
> The following entries are added in the axp209.dtsi 
> file: vhold-enable, vhold-set and ibus-limit
> The chosen default values are the AXP20X reset values, as described in the 
> data sheet.
> 
> Signed-off-by: Ene Alexandru <ene.alexandru at gmail.com>
> 
> 
> ---
> diff -uprN -X linux-sunxi-original/Documentation/dontdiff 
> linux-sunxi-original/arch/arm/boot/dts/axp209.dtsi 
> linux-sunxi/arch/arm/boot/dts/axp209.dtsi
> --- linux-sunxi-original/arch/arm/boot/dts/axp209.dtsi         2016-05-11 
> 09:21:47.470923679 +0200
> +++ linux-sunxi/arch/arm/boot/dts/axp209.dtsi     2016-05-10 
> 18:45:32.795158651 +0200
> @@ -98,5 +98,8 @@
>            usb_power_supply: usb_power_supply {
>                        compatible = "x-powers,axp202-usb-power-supply";
>                        status = "disabled";
> +                      vhold-enable = <0x01>;
> +                      vhold-set = <0x04>;
> +                      ibus-limit = <0x01>;
>            };
> };
> ---
> 


-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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