[U-Boot] [PATCH] mmc: fix the wrong dislabing clock

Jaehoon Chung jh80.chung at samsung.com
Wed Jan 17 10:36:58 UTC 2018


When power is off, clock is not disabling.
Because it's passed to 1, mmc->clock should be set to f_min value.
Some drivers can't initialize the eMMC/SD card with current status.

This patch is to fix the disabling clock value to 0.

Fixes: 2e7410d76ad1 ("mmc: disable the mmc clock during power off")

Signed-off-by: Jaehoon Chung <jh80.chung at samsung.com>
---
 drivers/mmc/mmc.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 53c819187e..311f51f237 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -1501,11 +1501,13 @@ static int mmc_set_ios(struct mmc *mmc)
 
 int mmc_set_clock(struct mmc *mmc, uint clock, bool disable)
 {
-	if (clock > mmc->cfg->f_max)
-		clock = mmc->cfg->f_max;
+	if (!disable && clock != 0) {
+		if (clock > mmc->cfg->f_max)
+			clock = mmc->cfg->f_max;
 
-	if (clock < mmc->cfg->f_min)
-		clock = mmc->cfg->f_min;
+		if (clock < mmc->cfg->f_min)
+			clock = mmc->cfg->f_min;
+	}
 
 	mmc->clock = clock;
 	mmc->clk_disable = disable;
@@ -2449,7 +2451,7 @@ static int mmc_power_on(struct mmc *mmc)
 
 static int mmc_power_off(struct mmc *mmc)
 {
-	mmc_set_clock(mmc, 1, true);
+	mmc_set_clock(mmc, 0, true);
 #if CONFIG_IS_ENABLED(DM_MMC) && CONFIG_IS_ENABLED(DM_REGULATOR)
 	if (mmc->vmmc_supply) {
 		int ret = regulator_set_enable(mmc->vmmc_supply, false);
-- 
2.15.1



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