[v1, 1/1] mmc: mtk-sd: receive cmd8 data when hs400 tuning fail

Mengqi Zhang mengqi.zhang at mediatek.com
Mon Jul 15 18:37:04 PDT 2024


When we use cmd8 as the tuning command in hs400 mode, the command
response sent back by some eMMC devices cannot be correctly sampled
by MTK eMMC controller at some weak sample timing. In this case,
command timeout error may occur. So we must receive the following
data to make sure the next cmd8 send correctly.

Signed-off-by: Mengqi Zhang <mengqi.zhang at mediatek.com>
Fixes: c4ac38c6539b ("mmc: mtk-sd: Add HS400 online tuning support")
Cc: stable at vger.stable.com
---
 drivers/mmc/host/mtk-sd.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
index a94835b8ab93..e386f78e3267 100644
--- a/drivers/mmc/host/mtk-sd.c
+++ b/drivers/mmc/host/mtk-sd.c
@@ -1230,7 +1230,7 @@ static bool msdc_cmd_done(struct msdc_host *host, int events,
 	}
 
 	if (!sbc_error && !(events & MSDC_INT_CMDRDY)) {
-		if (events & MSDC_INT_CMDTMO ||
+		if ((events & MSDC_INT_CMDTMO && !host->hs400_tuning) ||
 		    (!mmc_op_tuning(cmd->opcode) && !host->hs400_tuning))
 			/*
 			 * should not clear fifo/interrupt as the tune data
@@ -1323,9 +1323,9 @@ static void msdc_start_command(struct msdc_host *host,
 static void msdc_cmd_next(struct msdc_host *host,
 		struct mmc_request *mrq, struct mmc_command *cmd)
 {
-	if ((cmd->error &&
-	    !(cmd->error == -EILSEQ &&
-	      (mmc_op_tuning(cmd->opcode) || host->hs400_tuning))) ||
+	if ((cmd->error && !host->hs400_tuning &&
+	     !(cmd->error == -EILSEQ &&
+	     mmc_op_tuning(cmd->opcode))) ||
 	    (mrq->sbc && mrq->sbc->error))
 		msdc_request_done(host, mrq);
 	else if (cmd == mrq->sbc)
-- 
2.25.1




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