From ae11f09ab60621655cc407e7903ec3373e29b7fc Mon Sep 17 00:00:00 2001 From: San Mehat Date: Tue, 11 Nov 2008 09:35:36 -0800 Subject: [PATCH 057/696] mmc: sd: Add new CONFIG_MMC_PARANOID_SD_INIT for enabling retries during SD detection Signed-off-by: San Mehat --- drivers/mmc/core/Kconfig | 8 ++++++++ drivers/mmc/core/sd.c | 22 ++++++++++++++++++++++ 2 files changed, 30 insertions(+), 0 deletions(-) diff --git a/drivers/mmc/core/Kconfig b/drivers/mmc/core/Kconfig index ef10387..1972b00 100644 --- a/drivers/mmc/core/Kconfig +++ b/drivers/mmc/core/Kconfig @@ -27,3 +27,11 @@ 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 ff27741..fe75780 100644 --- a/drivers/mmc/core/sd.c +++ b/drivers/mmc/core/sd.c @@ -684,6 +684,9 @@ struct device_type sd_type = { int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid, u32 *rocr) { int err; +#ifdef CONFIG_MMC_PARANOID_SD_INIT + int retries; +#endif /* * Since we're changing the OCR value, we seem to @@ -790,7 +793,26 @@ 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; } -- 1.7.1