mmc: Retry the switch command
Some eMMC will fail at the first switch, but would succeed in a subsequent
one.
Make sure we try several times to cover those cases. The number of retries
(and the behaviour) is currently what is being used in Linux.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 4380c7c..d6b7e4f 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -494,6 +494,7 @@
{
struct mmc_cmd cmd;
int timeout = 1000;
+ int retries = 3;
int ret;
cmd.cmdidx = MMC_CMD_SWITCH;
@@ -502,11 +503,17 @@
(index << 16) |
(value << 8);
- ret = mmc_send_cmd(mmc, &cmd, NULL);
+ while (retries > 0) {
+ ret = mmc_send_cmd(mmc, &cmd, NULL);
- /* Waiting for the ready status */
- if (!ret)
- ret = mmc_send_status(mmc, timeout);
+ /* Waiting for the ready status */
+ if (!ret) {
+ ret = mmc_send_status(mmc, timeout);
+ return ret;
+ }
+
+ retries--;
+ }
return ret;