From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hans de Goede Subject: Re: [linux-sunxi] PATH[1/3] ARM: axp20x_usb_power.c add device tree configuration options for REG 30H: VBUS-IPSOUT Date: Fri, 10 Jun 2016 11:56:25 +0200 Message-ID: References: <0f58d2b3-f3d3-45a3-a307-e54df26c1ab1@googlegroups.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <0f58d2b3-f3d3-45a3-a307-e54df26c1ab1-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: ene.alexandru-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, linux-sunxi Cc: lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, sre-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, dbaryshkov-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org, wens-jdAy2FN1RRM@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org Hi, On 17-05-16 19:41, Ene Alexandru wrote: > 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 > > > --- > 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>; > }; > }; Please do not use raw register values like this, instead make the device-tree property take microvolts / microamps like e.g. the regulator bindings do, and translate these in the driver. Regards, Hans -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html