From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfram Sang Subject: Re: [RFC] thoughts about recent Samsung related patches Date: Mon, 6 Sep 2010 14:05:25 +0200 Message-ID: <20100906120525.GD2617@pengutronix.de> References: <20100906110059.GC2617@pengutronix.de> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="wULyF7TL5taEdwHz" Return-path: Received: from metis.ext.pengutronix.de ([92.198.50.35]:52772 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752554Ab0IFMF2 (ORCPT ); Mon, 6 Sep 2010 08:05:28 -0400 Content-Disposition: inline In-Reply-To: Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Kyungmin Park Cc: linux-mmc@vger.kernel.org, pierre-list@ossman.eu, gdavis@mvista.com, cbouatmailru@gmail.com, m.szyprowski@samsung.com, akpm@linux-foundation.org, =?utf-8?B?7KCV7J6s7ZuI?= --wULyF7TL5taEdwHz Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > > 2) 8-Bit data transfer support > > > > The comitted version ae6d6c92212e94b12ab9365c23fb73acc2c3c2e7 (sdhci: > > 8-bit data transfer width support) looks different from another RFC > > posted in February: > > http://www.mail-archive.com/linux-mmc@vger.kernel.org/msg01250.html > > > > As those two already differ, I think it might be wiser to move > > 8-bit-mode-handling to the platform-specific code? Even the documented > > features of a SDHC differ across implementations, I fear side-effects > > when using this kind of undocumented feature (official spec says > > "reserved" when describing this bit). >=20 > Okay it looks different from Samsung Spec. > WIDE8[5]: Extended Data Transfer Width (It is for MMC 8-bit card). > 1: 8-bit operatoin > 0: Bit width is designated by the bit 1(Data Transfer Width) > So no need to set the BIT 1 and BIT5 simultaneously. > I also wonder other Specs how described it. esdhc occupied BIT 2 (originally HI_SPD) for this :( %10 means 8 bit transfer. %11 is reserved. > Good, I think it's possible. I'll try and send a patch. Thanks! --=20 Pengutronix e.K. | Wolfram Sang | Industrial Linux Solutions | http://www.pengutronix.de/ | --wULyF7TL5taEdwHz Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iEYEARECAAYFAkyE2QUACgkQD27XaX1/VRvlRwCgoCsq7WKSImrErcQ/wJIne3Ym +6sAniNgnjqNEwOfCbMMXf0wtbKrV60E =lKPB -----END PGP SIGNATURE----- --wULyF7TL5taEdwHz--