From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sebastian Andrzej Siewior Subject: Re: [PATCH v2 2/2] USB: doc: Binding document for ehci-platform driver Date: Fri, 26 Oct 2012 10:02:54 +0200 Message-ID: <20121026080254.GD3009@breakpoint.cc> References: <20121025102301.GA3469@breakpoint.cc> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Alan Stern Cc: Sebastian Andrzej Siewior , Mitch Bradley , Stephen Warren , Greg KH , devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, USB list , Rob Herring , Florian Fainelli , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: devicetree@vger.kernel.org On Thu, Oct 25, 2012 at 10:36:14AM -0400, Alan Stern wrote: > What happens if the drivers get probed in the wrong order? That is, = if=20 > ehci-platform gets probed before ehci-spear (or whatever)? The "wrong" driver may get loaded. Right now, you should have them all = in one driver. For instance the crypto node in mpc8315erdb.dts: | crypto@30000 { | compatible =3D "fsl,sec3.3", "fsl,sec3.1", "fsl,sec3.0", | "fsl,sec2.4", "fsl,sec2.2", "fsl,sec2.1", | "fsl,sec2.0"; =E2=80=A6 The higher the version, the more features are available by the hardware= =2E The driver [0] probes only for "fsl,sec2.0" but it uses of_device_is_compatible() to check for the other entries. You could als= o add all 7 compatible entries to the driver and distinguish them by the driv= er_data field. This is an implementation detail. However, having two drivers, one for "fsl,sec3.3" and one for "fsl,sec2= =2E0", would "randomly" load one of the two driver depending on link order and= so on. [0] drivers/crypto/talitos.c >=20 > Alan Stern >=20 Sebastian -- 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