From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Brown Subject: Re: [PATCH 08/12] doc: binding: pwrseq-usb-generic: add binding doc for generic usb power sequence driver Date: Mon, 20 Jun 2016 18:06:10 +0100 Message-ID: <20160620170609.GA26099@sirena.org.uk> References: <1466158165-9380-1-git-send-email-peter.chen@nxp.com> <1466158165-9380-9-git-send-email-peter.chen@nxp.com> <20160620112651.GA26936@shlinux2> <20160620161607.GA11427@rob-hp-laptop> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="fKtH0JUtvN5p2ETH" Return-path: Content-Disposition: inline In-Reply-To: <20160620161607.GA11427@rob-hp-laptop> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Rob Herring Cc: Peter Chen , Peter Chen , Greg Kroah-Hartman , Alan Stern , Ulf Hansson , Sebastian Reichel , Mark Rutland , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Krzysztof =?utf-8?Q?Koz=C5=82owski?= , Stephen Boyd , oscar-Bdbr4918Nnnk1uMJSBkQmQ@public.gmane.org, Arnd Bergmann , Pawel Moll , "linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Sascha Hauer , Linux USB List , "linux-mmc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "Maciej S. Szmigiero" , troy.kisky-Q5RJGjKts06CY9SHAMCTRUEOCMrvLtNR@public.gmane.org, Javier Martinez Canillas , Philipp Zabel List-Id: linux-mmc@vger.kernel.org --fKtH0JUtvN5p2ETH Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jun 20, 2016 at 11:16:07AM -0500, Rob Herring wrote: > On Mon, Jun 20, 2016 at 07:26:51PM +0800, Peter Chen wrote: > > 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.=20 > This I have issue with. If you are creating a platform device here, you= =20 > are trying to work-around limitations in the linux driver model. Either= =20 > we need some sort of pre-probe hook to the drivers to call or each=20 > parent node driver is responsible for checking and calling pwr-seq=20 > functions for child nodes. e.g. The host controller calls pwr-seq for=20 > the hub, the hub driver calls the power seq for the asix chip. Soon as=20 > we have a case too complex for the generic pwr-seq, we're going to need= =20 > the pre-probe hook as I don't want to see a continual expansion of=20 > generic pwr-seq binding for ever more complex cases. I think it's fairly clear that we need one or both of these mechanisms for enumerable buses in embedded contexts - it's something that keeps croping up. --fKtH0JUtvN5p2ETH Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJXaCKAAAoJECTWi3JdVIfQSx0H/A8CgWBIxx6BRObIJtvZqknF Q3EiIP60kb6FR1CxObdWXAf7bx9gFZYaOQ4nyh1lS40woh55wStbDlsAfe3/xRVe ZgnwYlWgL2DVeyG0nqd3VFE+gTCVWgFZM0PMJrcNTUsVUItoRHeZHTPnskwuGa8i uVCBvvOjJ9vKenPNCpv9S8sqk51d1sQ/e9Z6ydy15xmQVNkTczSVpJW4H6N3mqYA IEugYPm3AzJ8fOFMrU84f2vwL7xPfnsZjseczRVobCebL1iJub0b+3WxlUUy1aiE oJ9uAVSYl0TOgo6HoWO3t4KFNU6MFNTlAwCRVmBzIIMhH9GYDOrZDOsP6awOEVE= =aFUu -----END PGP SIGNATURE----- --fKtH0JUtvN5p2ETH-- -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html