From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Chen Subject: Re: [PATCH v2 1/6] binding-doc: power: pwrseq-generic: add binding doc for generic power sequence library Date: Wed, 13 Jul 2016 16:42:50 +0800 Message-ID: <20160713084250.GB11863@shlinux2> References: <1468375610-18625-1-git-send-email-peter.chen@nxp.com> <1468375610-18625-2-git-send-email-peter.chen@nxp.com> <1468394851.3638.13.camel@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1468394851.3638.13.camel@pengutronix.de> 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: Philipp Zabel Cc: mark.rutland@arm.com, Peter Chen , ulf.hansson@linaro.org, stephen.boyd@linaro.org, k.kozlowski@samsung.com, festevam@gmail.com, stillcompiling@gmail.com, pawel.moll@arm.com, stern@rowland.harvard.edu, devicetree@vger.kernel.org, mail@maciej.szmigiero.name, arnd@arndb.de, linux-pm@vger.kernel.org, s.hauer@pengutronix.de, troy.kisky@boundarydevices.com, robh+dt@kernel.org, linux-arm-kernel@lists.infradead.org, oscar@naiandei.net, gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, sre@kernel.org, broonie@kernel.org, shawnguo@kernel.org List-Id: devicetree@vger.kernel.org On Wed, Jul 13, 2016 at 09:27:31AM +0200, Philipp Zabel wrote: > Am Mittwoch, den 13.07.2016, 10:06 +0800 schrieb Peter Chen: > > Add binding doc for generic power sequence library. > > > > Signed-off-by: Peter Chen > > --- > > .../bindings/power/pwrseq/pwrseq-generic.txt | 53 ++++++++++++++++++++++ > > 1 file changed, 53 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt > > > > diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt > > new file mode 100644 > > index 0000000..186c58c > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt > > @@ -0,0 +1,53 @@ > > +The generic power sequence library > > + > > +Some hard-wired USB/MMC devices need to do power sequence to let the > > +device work normally, > > I would replace "to let the device work normally" with "before the > device can be enumerated [on the bus]" here. > Ok. > > 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. > > + > > +The power sequence properties is under the device node. > > + > > +Required properties: > > +- power-sequence: this device needs to do power sequence before enumeration > > As Joshua pointed out, is this even needed at all? > If no, how we decide whether allocates pwrseq instance through pwrseq library or not? -- Best Regards, Peter Chen