From mboxrd@z Thu Jan 1 00:00:00 1970 From: swarren@wwwdotorg.org (Stephen Warren) Date: Wed, 29 Apr 2015 17:43:32 -0600 Subject: [PATCH 3/3] ARM: bcm2835: Add the necessary firmware driver information to the DT In-Reply-To: <87y4laq4nt.fsf@eliezer.anholt.net> References: <1430176449-12322-1-git-send-email-eric@anholt.net> <1430176449-12322-4-git-send-email-eric@anholt.net> <55403787.7010407@wwwdotorg.org> <87y4laq4nt.fsf@eliezer.anholt.net> Message-ID: <55416CA4.6040000@wwwdotorg.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 04/29/15 10:29, Eric Anholt wrote: > Stephen Warren writes: > >> On 04/27/2015 05:14 PM, Eric Anholt wrote: >>> This gets the USB power domain turned on so that DWC2 can probe, even >>> if the bootloader didn't turn it on for us (which is the case if you >>> use the RPi firmware without chainloading U-Boot). >> >>> diff --git a/arch/arm/boot/dts/bcm2835-rpi.dtsi b/arch/arm/boot/dts/bcm2835-rpi.dtsi >> >>> +&usb { >>> + power-domains = <&firmware POWER_DOMAIN_USB>; >>> +}; >> >> That property doesn't seem to be documented in >> Documentation/devicetree/bindings/usb/dwc2.txt (which defines compatible >> = "brcm,bcm2835-usb"). Is it implemented? > > power-domains is a generic property that's parsed by > drivers/base/power/domain.c. See also > Documentation/devicetree/bindings/power/power_domain.txt& Sure, but the binding for the node still needs to mention that it's acceptable for that property to exist (a/k/a that the USB binding inherits from or aggregates the power domains binding). Part of mentioning that would be a description of what the entries in the power-domains property mean (how many are legal, what each index represents).