From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chen-Yu Tsai Subject: Re: [PATCH 08/12] doc: binding: pwrseq-usb-generic: add binding doc for generic usb power sequence driver Date: Mon, 20 Jun 2016 20:29:55 +0800 Message-ID: References: <1466158165-9380-1-git-send-email-peter.chen@nxp.com> <1466158165-9380-9-git-send-email-peter.chen@nxp.com> <20160620112651.GA26936@shlinux2> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20160620112651.GA26936@shlinux2> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Peter Chen Cc: Mark Rutland , Peter Chen , Ulf Hansson , Stephen Boyd , =?UTF-8?Q?Krzysztof_Koz=C5=82owski?= , Fabio Estevam , Arnd Bergmann , Javier Martinez Canillas , Alan Stern , "devicetree@vger.kernel.org" , "Maciej S. Szmigiero" , Pawel Moll , "linux-pm@vger.kernel.org" , Sascha Hauer , troy.kisky@boundarydevices.com, Rob Herring , "linux-arm-kernel@lists.infradead.org" , oscar@naiandei.net, Greg Kroah-Hartman , Linux USB List , linux-mmc@vger List-Id: devicetree@vger.kernel.org Hi, On Mon, Jun 20, 2016 at 7:26 PM, Peter Chen wrote: > On Fri, Jun 17, 2016 at 12:16:48PM -0500, Rob Herring wrote: >> On Fri, Jun 17, 2016 at 5:09 AM, Peter Chen wrote: >> > Add binding doc for generic usb power sequence driver, and update >> > generic usb device binding-doc accordingly. >> > >> > Signed-off-by: Peter Chen >> > --- >> > .../bindings/power/pwrseq/pwrseq-usb-generic.txt | 31 ++++++++++++++++++++++ >> > .../devicetree/bindings/usb/usb-device.txt | 2 ++ >> > 2 files changed, 33 insertions(+) >> > create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-usb-generic.txt >> > >> > diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-usb-generic.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-usb-generic.txt >> > new file mode 100644 >> > index 0000000..8ad98382 >> > --- /dev/null >> > +++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-usb-generic.txt >> > @@ -0,0 +1,31 @@ >> > +The power sequence for generic USB Devices >> > + >> > +Some hard-wired USB devices need to do power sequence to let the >> > +device work normally, the typical power sequence like: enable USB >> > +PHY clock, toggle reset pin, etc. But current Linux USB driver >> > +lacks of such code to do it, it may cause some hard-wired USB devices >> > +works abnormal or can't be recognized by controller at all. The >> > +power sequence will be done before this device can be found at USB >> > +bus. >> > + >> > +Required properties: >> > +- compatible : contains "usb-pwrseq-generic". >> >> In case I have not been clear, no. >> >> I am not going to accept anything along the lines of the current mmc >> pwrseq. I am basically okay with Krzysztof's proposal as it is *only* >> an added property and not a duplication of information. I'd suggest >> you figure out how to make the kernel work with that rather than >> trying to work-around whatever kernel limitations there are. >> > > I see. > > Would you agree with below: > > &usbotg1 { > vbus-supply = <®_usb_otg1_vbus>; > pinctrl-names = "default"; > pinctrl-0 = <&pinctrl_usb_otg1_id>; > status = "okay"; > > #address-cells = <1>; > #size-cells = <0>; > hub: genesys@1 { > compatible = "usb5e3,608"; > reg = <1>; > > power-sequence; > reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>; /* hub reset pin */ > reset-duration-us = <10>; > clocks = <&clks IMX6SX_CLK_CKO>; > > #address-cells = <1>; > #size-cells = <0>; > ethernet: asix@1 { > compatible = "usbb95,1708"; > reg = <1>; > > power-sequence; > reset-gpios = <&gpio4 6 GPIO_ACTIVE_LOW>; /* ethernet_rst */ > reset-duration-us = <15>; > clocks = <&clks IMX6SX_CLK_IPG>; > }; > }; > }; > > If the node has property "power-sequence", the pwrseq core will create > related platform device, and the driver under pwrseq driver will handle > power sequence stuffs. The property below "power-sequence" will be > handled at pwrseq driver. Isn't this binding what Krzysztof proposed? His series also provides example code for enabling USB device power sequencing. Does it not work for you? Having 2 series by 2 separate people doing the same thing but slightly different is very confusing. Regards ChenYu