diff options
| author | San Mehat <san@google.com> | 2008-11-11 09:35:36 -0800 |
|---|---|---|
| committer | John Stultz <john.stultz@linaro.org> | 2016-02-16 13:51:02 -0800 |
| commit | 94d5306d03e52653ebc18136166ad142845f99de (patch) | |
| tree | 875499cb9bfddbef7d0d1eb7f39611ff01de41e6 | |
| parent | 91fa97e1e5c001d52f6c993d37be08d1e84f47b7 (diff) | |
mmc: sd: Add new CONFIG_MMC_PARANOID_SD_INIT for enabling retries during SD detection
Signed-off-by: San Mehat <san@google.com>
| -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 4c33d7690f2f..319c68d7b0f4 100644 --- a/drivers/mmc/core/Kconfig +++ b/drivers/mmc/core/Kconfig @@ -1,3 +1,11 @@ # # MMC core configuration # + +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 141eaa923e18..db828959d6d1 100644 --- a/drivers/mmc/core/sd.c +++ b/drivers/mmc/core/sd.c @@ -809,6 +809,9 @@ 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) { /* @@ -835,7 +838,26 @@ 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; } |