mmc: add additional quirk for APP_CMD retry
It was observed (on ClearFog Base) that sending MMC APP_CMD returned
an error on the first attempt. The issue appears to be timing related
since even inserting a puts() short debug entry before the execution
added sufficient delay to receive success on first attempt.
Follow the existing quirks pattern to retry if initial issuance
failed so as to not introduce any delay unless needed.
Signed-off-by: Joel Johnson <mrjoel@lixil.net>
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index f683b52..d43983d 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -1444,6 +1444,20 @@
cmd.cmdarg = mmc->rca << 16;
err = mmc_send_cmd(mmc, &cmd, NULL);
+#ifdef CONFIG_MMC_QUIRKS
+ if (err && (mmc->quirks & MMC_QUIRK_RETRY_APP_CMD)) {
+ int retries = 4;
+ /*
+ * It has been seen that APP_CMD may fail on the first
+ * attempt, let's try a few more times
+ */
+ do {
+ err = mmc_send_cmd(mmc, &cmd, NULL);
+ if (!err)
+ break;
+ } while (retries--);
+ }
+#endif
if (err)
return err;
@@ -2755,7 +2769,8 @@
#ifdef CONFIG_MMC_QUIRKS
mmc->quirks = MMC_QUIRK_RETRY_SET_BLOCKLEN |
- MMC_QUIRK_RETRY_SEND_CID;
+ MMC_QUIRK_RETRY_SEND_CID |
+ MMC_QUIRK_RETRY_APP_CMD;
#endif
err = mmc_power_cycle(mmc);