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 BC1C4B7091 for ; Sat, 6 Jun 2009 21:19:37 +1000 (EST) Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [92.198.50.35]) by ozlabs.org (Postfix) with ESMTP id 409C0DDD1B for ; Sat, 6 Jun 2009 21:19:37 +1000 (EST) Date: Sat, 6 Jun 2009 13:19:26 +0200 From: Wolfram Sang To: David Woodhouse Subject: Re: [PATCH V2 2/2] mtd/maps/mtd-ram: add an of-platform driver Message-ID: <20090606111926.GA3279@pengutronix.de> References: <1244203514-12516-1-git-send-email-w.sang@pengutronix.de> <1244203514-12516-3-git-send-email-w.sang@pengutronix.de> <1244276049.3751.1176.camel@macbook.infradead.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="3V7upXqbjpZ4EhLz" In-Reply-To: <1244276049.3751.1176.camel@macbook.infradead.org> Cc: devicetree-discuss@ozlabs.org, albrecht.dress@arcor.de, linuxppc-dev@ozlabs.org, linux-mtd@lists.infradead.org, Ben Dooks List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --3V7upXqbjpZ4EhLz Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sat, Jun 06, 2009 at 09:14:08AM +0100, David Woodhouse wrote: > On Fri, 2009-06-05 at 14:05 +0200, Wolfram Sang wrote: > > Create an of-aware driver using the now exported generic functions from > > plat-ram.c. Also add the documentation for the binding. Partitions are > > not yet supported. Tested on a phyCORE-MPC5200B-IO. >=20 > Do we have an ack for the device-tree bindings?=20 >=20 > It _would_ be possible to hook up RAM through the existing of_physmap > driver, I think -- although it would be slightly less efficient that > way. >=20 > Maybe cleaner from the device-tree POV though. And if we want to put a > special case in the _code_ to make it more efficient, we can do that. During development, I also checked physmap_of.c and found this binding: { .type =3D "rom", .compatible =3D "direct-mapped" }, which made some sense to me and I thought about .type =3D "ram". However, I= then found this in the code: /* Helper function to handle probing of the obsolete "direct-mapped" * compatible binding, which has an extra "probe-type" property * describing the type of flash probe necessary. */ static struct mtd_info * __devinit obsolete_probe(struct of_device *dev, struct map_info *map) { [...] dev_warn(&dev->dev, "Device tree uses obsolete \"direct-mapped\" " "flash binding\n"); My conclusion was then that a mtd-ram binding wouldn't belong here, but I h= ave maybe misinterpreted things... Regards, Wolfram --=20 Pengutronix e.K. | Wolfram Sang | Industrial Linux Solutions | http://www.pengutronix.de/ | --3V7upXqbjpZ4EhLz 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) iEYEARECAAYFAkoqUL4ACgkQD27XaX1/VRujcgCfaC0oE0HFX1XXmPmsivP0MN2s WnIAniT/ONI9qNUFXF1wBUP9BtTVclh1 =9yH8 -----END PGP SIGNATURE----- --3V7upXqbjpZ4EhLz--