From patchwork Fri May 27 06:37:05 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shawn Lin X-Patchwork-Id: 9137729 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1307160467 for ; Fri, 27 May 2016 06:37:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0511627CEC for ; Fri, 27 May 2016 06:37:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id EC22B28093; Fri, 27 May 2016 06:37:45 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9384127CEC for ; Fri, 27 May 2016 06:37:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754994AbcE0Ghb (ORCPT ); Fri, 27 May 2016 02:37:31 -0400 Received: from lucky1.263xmail.com ([211.157.147.135]:40399 "EHLO lucky1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754985AbcE0Gh2 (ORCPT ); Fri, 27 May 2016 02:37:28 -0400 Received: from shawn.lin?rock-chips.com (unknown [192.168.167.105]) by lucky1.263xmail.com (Postfix) with SMTP id B2711822; Fri, 27 May 2016 14:37:20 +0800 (CST) X-263anti-spam: KSV:0; X-MAIL-GRAY: 1 X-MAIL-DELIVERY: 0 X-KSVirus-check: 0 X-ABS-CHECKED: 4 X-ADDR-CHECKED: 0 Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.263.net (Postfix) with ESMTP id 1FE1A24042; Fri, 27 May 2016 14:37:16 +0800 (CST) X-RL-SENDER: shawn.lin@rock-chips.com X-FST-TO: jh80.chung@samsung.com X-SENDER-IP: 58.22.7.114 X-LOGIN-NAME: shawn.lin@rock-chips.com X-UNIQUE-TAG: <894553a968df5275585e2ecced35ffb7> X-ATTACHMENT-NUM: 0 X-SENDER: lintao@rock-chips.com X-DNS-TYPE: 0 Received: from localhost.localdomain (unknown [58.22.7.114]) by smtp.263.net (Postfix) whith ESMTP id 29062LDADSP; Fri, 27 May 2016 14:37:17 +0800 (CST) From: Shawn Lin To: Jaehoon Chung , Ulf Hansson Cc: linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, Doug Anderson , linux-rockchip@lists.infradead.org, Shawn Lin Subject: [PATCH v2 2/2] mmc: dw_mmc: check card present before starting request Date: Fri, 27 May 2016 14:37:05 +0800 Message-Id: <1464331025-16275-1-git-send-email-shawn.lin@rock-chips.com> X-Mailer: git-send-email 1.8.0 Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The main reason to add this check is to avoid unnecessary mmc_request like the on-going cmd and the corresponding sbc if the card is removed. Although we have already checked this in dw_mci_handle_cd for runtime usage of sd card and dw_mci_init_slot for noremovable devices, but there is a timing gap before it really calls dw_mci_get_cd as mmc_detect_change needs some delay here. Another gain here is that we could save some checkings of card status after sd card been removed. Signed-off-by: Shawn Lin --- Changes in v2: - hold lock before dw_mci_queue_request drivers/mmc/host/dw_mmc.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c index cb30e91..2b4b3df 100644 --- a/drivers/mmc/host/dw_mmc.c +++ b/drivers/mmc/host/dw_mmc.c @@ -105,6 +105,7 @@ struct idmac_desc { static bool dw_mci_reset(struct dw_mci *host); static bool dw_mci_ctrl_reset(struct dw_mci *host, u32 reset); static int dw_mci_card_busy(struct mmc_host *mmc); +static int dw_mci_get_cd(struct mmc_host *mmc); #if defined(CONFIG_DEBUG_FS) static int dw_mci_req_show(struct seq_file *s, void *v) @@ -1253,15 +1254,15 @@ static void dw_mci_request(struct mmc_host *mmc, struct mmc_request *mrq) * atomic, otherwise the card could be removed in between and the * request wouldn't fail until another card was inserted. */ - spin_lock_bh(&host->lock); - if (!test_bit(DW_MMC_CARD_PRESENT, &slot->flags)) { - spin_unlock_bh(&host->lock); + if (!dw_mci_get_cd(mmc)) { mrq->cmd->error = -ENOMEDIUM; mmc_request_done(mmc, mrq); return; } + spin_lock_bh(&host->lock); + dw_mci_queue_request(host, slot, mrq); spin_unlock_bh(&host->lock);