[U-Boot] [PATCH 2/4] mmc: atmel: Fix clock configuration

Marek Vasut marex at denx.de
Fri Oct 23 20:46:29 CEST 2015


After silencing the prints which were generated when reconfiguring the
clock of the SD/MMC bus, surprisingly, the driver stopped working such
that every attempt to use the SD/MMC bus caused the CPU to get totally
stuck hard. It turns out that the prints generated a short delay, which
was necessary for the CPU to reconfigure the clock without getting stuck.
Thus, this patch adds a short delay after the clock configuration instead.

Signed-off-by: Marek Vasut <marex at denx.de>
---
 drivers/mmc/gen_atmel_mci.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/mmc/gen_atmel_mci.c b/drivers/mmc/gen_atmel_mci.c
index 2815e57..8b05fcd 100644
--- a/drivers/mmc/gen_atmel_mci.c
+++ b/drivers/mmc/gen_atmel_mci.c
@@ -113,6 +113,8 @@ static void mci_set_mode(struct mmc *mmc, u32 hz, u32 blklen)
 	if (mmc->card_caps & mmc->cfg->host_caps & MMC_MODE_HS)
 		writel(MMCI_BIT(HSMODE), &mci->cfg);
 
+	udelay(50);
+
 	initialized = 1;
 }
 
-- 
2.1.4



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