diff options
| author | San Mehat <san@google.com> | 2011-12-13 01:21:48 +0800 |
|---|---|---|
| committer | Andy Green <andy.green@linaro.org> | 2011-12-26 16:41:56 +0800 |
| commit | d4d25853c28ed9f0525664ceb6f9ed8d3f41a872 (patch) | |
| tree | 905aac0e0002ea9da7fe50c3f6fb5615a8339ed4 /drivers | |
| parent | b285c15889a5153d2a1468e94bd4804c58239ba7 (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 f2a05ea40f2..e3934db234b 100644 --- a/drivers/mmc/core/sd.c +++ b/drivers/mmc/core/sd.c @@ -720,6 +720,9 @@ 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 @@ -826,7 +829,26 @@ 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; } |