From ff172d75e3d50c12f92516a80c6228a8f365888b Mon Sep 17 00:00:00 2001 From: San Mehat Date: Tue, 11 Nov 2008 09:35:36 -0800 Subject: [PATCH] ANDROID: mmc: sd: Add new CONFIG_MMC_PARANOID_SD_INIT for enabling retries during SD detection Change-Id: I4e6b9d9a3600d7efbee1d8379e45db11c57827f2 Signed-off-by: San Mehat --- drivers/mmc/core/Kconfig | 7 +++++++ drivers/mmc/core/sd.c | 22 ++++++++++++++++++++++ 2 files changed, 29 insertions(+) diff --git a/drivers/mmc/core/Kconfig b/drivers/mmc/core/Kconfig index 42e89060cd41..0b004586c803 100644 --- a/drivers/mmc/core/Kconfig +++ b/drivers/mmc/core/Kconfig @@ -80,3 +80,10 @@ config MMC_TEST This driver is only of interest to those developing or testing a host driver. Most people should say N here. +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 4fd1620b732d..e85524cc3659 100644 --- a/drivers/mmc/core/sd.c +++ b/drivers/mmc/core/sd.c @@ -834,6 +834,9 @@ 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) { /* @@ -860,7 +863,26 @@ 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; } -- 2.20.1