diff options
| author | San Mehat <san@google.com> | 2008-11-11 09:35:36 -0800 |
|---|---|---|
| committer | Colin Cross <ccross@android.com> | 2012-02-14 11:26:10 -0800 |
| commit | b22fdab146fdf7bf910346a845d9f55bc8aee09b (patch) | |
| tree | ff0e192b8f7a4799461ccc6340cfb1031eea80d3 /drivers | |
| parent | 42dd11907fff6a716766fedcaead5ec0e2211d95 (diff) | |
mmc: sd: Add new CONFIG_MMC_PARANOID_SD_INIT for enabling retries during SD detection
Signed-off-by: San Mehat <san@google.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/mmc/core/Kconfig | 8 | ||||
| -rw-r--r-- | 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 ef103871517..1972b00f801 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 c63ad03c29c..eeae54163a8 100644 --- a/drivers/mmc/core/sd.c +++ b/drivers/mmc/core/sd.c @@ -721,6 +721,9 @@ 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 @@ -827,7 +830,26 @@ 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; } |