Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932196AbaKROJz (ORCPT ); Tue, 18 Nov 2014 09:09:55 -0500 Received: from cantor2.suse.de ([195.135.220.15]:57164 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932103AbaKROJo (ORCPT ); Tue, 18 Nov 2014 09:09:44 -0500 From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Roger Tseng , Ulf Hansson , Jiri Slaby Subject: [PATCH 3.12 058/206] mmc: rtsx_pci_sdmmc: fix incorrect last byte in R2 response Date: Tue, 18 Nov 2014 15:06:53 +0100 Message-Id: <87394e735e609660eceb70e505f6d8b7c7a1eaba.1416319692.git.jslaby@suse.cz> X-Mailer: git-send-email 2.1.3 In-Reply-To: <28f04bcc068a44c5641c727883947960fb8dcbd5.1416319692.git.jslaby@suse.cz> References: <28f04bcc068a44c5641c727883947960fb8dcbd5.1416319692.git.jslaby@suse.cz> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Roger Tseng 3.12-stable review patch. If anyone has any objections, please let me know. =============== 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: Jiri Slaby --- 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 54e8ba45c3ad..2985efd7bdb2 100644 --- a/drivers/mmc/host/rtsx_pci_sdmmc.c +++ b/drivers/mmc/host/rtsx_pci_sdmmc.c @@ -342,6 +342,13 @@ 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", -- 2.1.3 -- 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/