From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754671AbbJ0IzW (ORCPT ); Tue, 27 Oct 2015 04:55:22 -0400 Received: from mail-wi0-f173.google.com ([209.85.212.173]:34073 "EHLO mail-wi0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752996AbbJ0IzT (ORCPT ); Tue, 27 Oct 2015 04:55:19 -0400 From: =?UTF-8?q?B=C3=A1lint=20Czobor?= Cc: linux-kernel@vger.kernel.org, llinux-mmc@vger.kernel.org, San Mehat , =?UTF-8?q?B=C3=A1lint=20Czobor?= Subject: [PATCH 1/3] mmc: sd: Add new CONFIG_MMC_PARANOID_SD_INIT for enabling retries during SD detection Date: Tue, 27 Oct 2015 09:55:07 +0100 Message-Id: <1445936107-5939-1-git-send-email-czoborbalint@gmail.com> X-Mailer: git-send-email 1.7.9.5 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit To: unlisted-recipients:; (no To-header on input) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: San Mehat Signed-off-by: San Mehat Signed-off-by: Bálint Czobor --- drivers/mmc/core/Kconfig | 8 ++++++++ drivers/mmc/core/sd.c | 22 ++++++++++++++++++++++ 2 files changed, 30 insertions(+) diff --git a/drivers/mmc/core/Kconfig b/drivers/mmc/core/Kconfig index 9ebee72..1d284c1 100644 --- a/drivers/mmc/core/Kconfig +++ b/drivers/mmc/core/Kconfig @@ -11,3 +11,11 @@ config MMC_CLKGATE support handling this in order for it to be of any use. If unsure, say N. + +config MMC_PARANOID_SD_INIT + bool "Enable paranoid SD card initialization (EXPERIMENTAL)" + help + If you say Y here, the MMC layer will be extra paranoid + about re-trying SD init requests. This can be a useful + work-around for buggy controllers and hardware. Enable + if you are experiencing issues with SD detection. diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c index 4e7366a..dcbbd33 100644 --- a/drivers/mmc/core/sd.c +++ b/drivers/mmc/core/sd.c @@ -797,6 +797,9 @@ int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card, bool reinit) { int err; +#ifdef CONFIG_MMC_PARANOID_SD_INIT + int retries; +#endif if (!reinit) { /* @@ -823,7 +826,26 @@ int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card, /* * Fetch switch information from card. */ +#ifdef CONFIG_MMC_PARANOID_SD_INIT + for (retries = 1; retries <= 3; retries++) { + err = mmc_read_switch(card); + if (!err) { + if (retries > 1) { + printk(KERN_WARNING + "%s: recovered\n", + mmc_hostname(host)); + } + break; + } else { + printk(KERN_WARNING + "%s: read switch failed (attempt %d)\n", + mmc_hostname(host), retries); + } + } +#else err = mmc_read_switch(card); +#endif + if (err) return err; } -- 1.7.9.5