[PATCH v2 1/1] mmc: core: Add HS400 tuning in HS400es initialization

Mengqi Zhang mengqi.zhang at mediatek.com
Thu Dec 21 22:22:36 PST 2023


During the initialization to HS400es stage, add hs400 tuning flow as an
optional process. For Mediatek IP, HS00es mode requires a specific tuning to
ensure the correct HS400 timing setting.

Signed-off-by: Mengqi Zhang <mengqi.zhang at mediatek.com>
---
the previous patch link:
https://patchwork.kernel.org/project/linux-mediatek/patch/20231201030547.11553-1-mengqi.zhang@mediatek.com/
---
 drivers/mmc/core/mmc.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 705942edacc6..9760eea2c104 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1823,7 +1823,15 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
 		if (err)
 			goto free_card;
 
-	} else if (!mmc_card_hs400es(card)) {
+	} else if (mmc_card_hs400es(card)) {
+		if (host->ops->execute_hs400_tuning) {
+			mmc_retune_disable(host);
+			err = host->ops->execute_hs400_tuning(host, card);
+			mmc_retune_enable(host);
+			if (err)
+				goto free_card;
+		}
+	} else {
 		/* Select the desired bus width optionally */
 		err = mmc_select_bus_width(card);
 		if (err > 0 && mmc_card_hs(card)) {
-- 
2.25.1




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