[PATCH 4.9 012/240] mmc: core: Do a power cycle when the CMD11 fails

Greg Kroah-Hartman
2021-05-20T11:02:14Z

From: DooHyun Hwang <dh0421.hwang@samsung.com>

commit 147186f531ae49c18b7a9091a2c40e83b3d95649 upstream.

A CMD11 is sent to the SD/SDIO card to start the voltage switch procedure
into 1.8V I/O. According to the SD spec a power cycle is needed of the
card, if it turns out that the CMD11 fails. Let's fix this, to allow a
retry of the initialization without the voltage switch, to succeed.

Note that, whether it makes sense to also retry with the voltage switch
after the power cycle is a bit more difficult to know. At this point, we
treat it like the CMD11 isn't supported and therefore we skip it when
retrying.

Signed-off-by: DooHyun Hwang <dh0421.hwang@samsung.com>
Link: https://lore.kernel.org/r/20210210045936.7809-1-dh0421.hwang@samsung.com
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/mmc/core/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1691,7 +1691,7 @@ int mmc_set_signal_voltage(struct mmc_ho

err = mmc_wait_for_cmd(host, &cmd, 0);
if (err)
- return err;
+ goto power_cycle;

if (!mmc_host_is_spi(host) && (cmd.resp[0] & R1_ERROR))
return -EIO;