[lkml]   [2021]   [Feb]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH] mmc: core: add a power cycle when CMD11 fails
A power cycle is required if CMD11 fails.
CMD11 failure should be handled as no response.

If there is a timeout error that means no response to the CMD11,
do not send the CMD11 again and the power cycle is required.
Any other errors for CMD11 are the same because CMD11 failed.

On some bad SD Card, CMD11 may fail but the card may have already
invoked the voltage switch sequence.
In this case, it is necessary to retry without voltage switching
after power cycle.

Signed-off-by: DooHyun Hwang <>
drivers/mmc/core/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 1136b859ddd8..a6674df2a7bb 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1207,7 +1207,7 @@ int mmc_set_uhs_voltage(struct mmc_host *host, u32 ocr)

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;
 \ /
  Last update: 2021-02-10 06:13    [W:0.117 / U:0.344 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site