From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [203.10.76.45]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mx.ozlabs.org", Issuer "CA Cert Signing Authority" (verified OK)) by bilbo.ozlabs.org (Postfix) with ESMTPS id 96280B714E for ; Tue, 16 Jun 2009 19:04:57 +1000 (EST) Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [92.198.50.35]) by ozlabs.org (Postfix) with ESMTP id 141B8DDDA1 for ; Tue, 16 Jun 2009 19:04:57 +1000 (EST) Date: Tue, 16 Jun 2009 11:04:35 +0200 From: Wolfram Sang To: Grant Likely Subject: Re: [PATCH 2/2] uio: add an of_genirq driver Message-ID: <20090616090435.GA21321@pengutronix.de> References: <1244765062-14144-1-git-send-email-w.sang@pengutronix.de> <1244765062-14144-3-git-send-email-w.sang@pengutronix.de> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="OgqxwSJOaUobr8KG" In-Reply-To: Cc: devicetree-discuss@ozlabs.org, "Hans J. Koch" , linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, Greg KH List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --OgqxwSJOaUobr8KG Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > > diff --git a/Documentation/powerpc/dts-bindings/uio-generic.txt b/Docum= entation/powerpc/dts-bindings/uio-generic.txt > > new file mode 100644 > > index 0000000..8ad9861 > > --- /dev/null > > +++ b/Documentation/powerpc/dts-bindings/uio-generic.txt > > @@ -0,0 +1,16 @@ > > +UIO for custom devices > > + > > +A device which will be mapped using the UIO subsystem. > > + > > +Properties: > > + - compatible : should contain the specific model used, followed by > > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0"generic-uio". > > + - reg : address range(s) of the device (up to MAX_UIO_MAPS) > > + - interrupts : interrupt of the device > > + > > +Example: > > + =A0 =A0 =A0 =A0c64fpga@0 { > > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0compatible =3D "ptx,c64fpga001", "gene= ric-uio"; > > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0reg =3D <0x0 0x10000>; > > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0interrupts =3D <0 0 3>; > > + =A0 =A0 =A0 =A0}; >=20 > Hmmm, I'm not happy about this. The device tree describes the > hardware, not the way Linux uses the hardware. UIO definitely falls > into the category of Linux implementation detail. Yes, I am aware of that. I just started with the mechanisms which are avail= able today and hoped we could find some compatible-value which will suit all nee= ds. > This should be approached from the other way around. Either the > generic-uio of_platform driver should contain an explicit list of > devices to be handled by UIO, Well, that could lead to a quite huge match_table over time. > or the OF infrastructure should be modified to allow things like force > binding of_devices to of_drivers at runtime. That is an interesting idea. I could imagine something like a 'new_compatib= le" entry in the sysfs-section of the driver similar to 'new_id' for PCI. After writing a new compatible-string into it, matching will triggered again with= the new entry added. That could (should?) also be placed at the of-core-level. = Or did you have something else in mind? Regards, Wolfram --=20 Pengutronix e.K. | Wolfram Sang | Industrial Linux Solutions | http://www.pengutronix.de/ | --OgqxwSJOaUobr8KG Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEARECAAYFAko3YCMACgkQD27XaX1/VRswtwCcDtPiiseb3Z92cZ6a+o9qGHNi k+wAnAubWxlG7Oi6ZRW2G0NMueA8Gwsh =0vEj -----END PGP SIGNATURE----- --OgqxwSJOaUobr8KG--