From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753669AbaLUOEs (ORCPT ); Sun, 21 Dec 2014 09:04:48 -0500 Received: from gloria.sntech.de ([95.129.55.99]:43701 "EHLO gloria.sntech.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752765AbaLUOEr (ORCPT ); Sun, 21 Dec 2014 09:04:47 -0500 From: Heiko =?ISO-8859-1?Q?St=FCbner?= To: Doug Anderson Cc: Addy Ke , Jaehoon Chung , Seungwon Jeon , Ulf Hansson , Alim Akhtar , Sonny Rao , Andrew Bresticker , linux-rockchip@lists.infradead.org, robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, linux@arm.linux.org.uk, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] ARM: dts: Bump SD card pin drive strength up on rk3288-evb Date: Sun, 21 Dec 2014 15:04:13 +0100 Message-ID: <2971473.Y1akaDeraL@phil> User-Agent: KMail/4.14.2 (Linux/3.16-3-amd64; KDE/4.14.1; x86_64; ; ) In-Reply-To: <1418244929-8254-1-git-send-email-dianders@chromium.org> References: <1418244929-8254-1-git-send-email-dianders@chromium.org> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Mittwoch, 10. Dezember 2014, 12:55:29 schrieb Doug Anderson: > It seems that ever since (536f6b9 mmc: dw_mmc: Reset DMA before > enabling IDMAC) landed upstream that SD cards have been very unhappy > on rk3288-evb. They were a little unhappy before that change, but > after that change they're REALLY unhappy. > > It turns out that the above fix happens to fix a corruption when > reading card information during probe time. Without the fix we didn't > detect that high speed SD cards could actually support high speed. > With the fix we suddenly detect that they're high speed and we try to > use them at 50MHz. That doesn't work so well on EVB with the default > drive strength (maybe because there are two physical SD card slots > hooked up to the same pin?). > > Fix the problem by bumping up the drive strength of the sdmmc lines. > > Signed-off-by: Doug Anderson > Fixes: 536f6b91d21b ("mmc: dw_mmc: Reset DMA before enabling IDMAC") applied to my 3.19 dts-fixes branch (after a slight modification of the subject: please use "ARM: dts: rockchip:") Heiko