Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754688AbaKYLlo (ORCPT ); Tue, 25 Nov 2014 06:41:44 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:58383 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753149AbaKYKlY (ORCPT ); Tue, 25 Nov 2014 05:41:24 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Roger Tseng , Ulf Hansson , Luis Henriques Subject: [PATCH 3.16.y-ckt 082/254] mmc: rtsx_pci_sdmmc: fix incorrect last byte in R2 response Date: Tue, 25 Nov 2014 10:37:12 +0000 Message-Id: <1416912004-5928-83-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1416912004-5928-1-git-send-email-luis.henriques@canonical.com> References: <1416912004-5928-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt2 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Roger Tseng commit d1419d50c1bf711e9fd27b516a739c86b23f7cf9 upstream. Current code erroneously fill the last byte of R2 response with an undefined value. In addition, the controller actually 'offloads' the last byte (CRC7, end bit) while receiving R2 response and thus it's impossible to get the actual value. This could cause mmc stack to obtain inconsistent CID from the same card after resume and misidentify it as a different card. Fix by assigning dummy CRC and end bit: {7'b0, 1} = 0x1 to the last byte of R2. Fixes: ff984e57d36e ("mmc: Add realtek pcie sdmmc host driver") Signed-off-by: Roger Tseng Signed-off-by: Ulf Hansson Signed-off-by: Luis Henriques --- drivers/mmc/host/rtsx_pci_sdmmc.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/mmc/host/rtsx_pci_sdmmc.c b/drivers/mmc/host/rtsx_pci_sdmmc.c index 0d519649b575..a92a0daddaaa 100644 --- a/drivers/mmc/host/rtsx_pci_sdmmc.c +++ b/drivers/mmc/host/rtsx_pci_sdmmc.c @@ -332,6 +332,13 @@ static void sd_send_cmd_get_rsp(struct realtek_pci_sdmmc *host, } if (rsp_type == SD_RSP_TYPE_R2) { + /* + * The controller offloads the last byte {CRC-7, end bit 1'b1} + * of response type R2. Assign dummy CRC, 0, and end bit to the + * byte(ptr[16], goes into the LSB of resp[3] later). + */ + ptr[16] = 1; + for (i = 0; i < 4; i++) { cmd->resp[i] = get_unaligned_be32(ptr + 1 + i * 4); dev_dbg(sdmmc_dev(host), "cmd->resp[%d] = 0x%08x\n", -- 2.1.0 -- 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/