Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754586Ab2JGXcQ (ORCPT ); Sun, 7 Oct 2012 19:32:16 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:38556 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754520Ab2JGXXC (ORCPT ); Sun, 7 Oct 2012 19:23:02 -0400 Message-Id: <20121007225842.722868544@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Sun, 07 Oct 2012 23:59:32 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Al Cooper , Arindam Nath , Philip Rakity , Girish K S , Chris Ball Subject: [ 058/108] mmc: Prevent 1.8V switch for SD hosts that dont support UHS modes. In-Reply-To: <20121007225834.673681075@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:21c:bfff:fe03:f805 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1985 Lines: 50 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Al Cooper commit 4188bba0e9e7ba58d231b528df495666f2742b74 upstream. The driver should not try to switch to 1.8V when the SD 3.0 host controller does not have any UHS capabilities bits set (SDR50, DDR50 or SDR104). See page 72 of "SD Specifications Part A2 SD Host Controller Simplified Specification Version 3.00" under "1.8V Signaling Enable". Instead of setting SDR12 and SDR25 in the host capabilities data structure for all V3.0 host controllers, only set them if SDR104, SDR50 or DDR50 is set in the host capabilities register. This will prevent the switch to 1.8V later. Signed-off-by: Al Cooper Acked-by: Arindam Nath Acked-by: Philip Rakity Acked-by: Girish K S Signed-off-by: Chris Ball Signed-off-by: Ben Hutchings --- drivers/mmc/host/sdhci.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 8262cad..9aa77f3 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -2782,8 +2782,9 @@ int sdhci_add_host(struct sdhci_host *host) mmc_card_is_removable(mmc)) mmc->caps |= MMC_CAP_NEEDS_POLL; - /* UHS-I mode(s) supported by the host controller. */ - if (host->version >= SDHCI_SPEC_300) + /* Any UHS-I mode in caps implies SDR12 and SDR25 support. */ + if (caps[1] & (SDHCI_SUPPORT_SDR104 | SDHCI_SUPPORT_SDR50 | + SDHCI_SUPPORT_DDR50)) mmc->caps |= MMC_CAP_UHS_SDR12 | MMC_CAP_UHS_SDR25; /* SDR104 supports also implies SDR50 support */ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/