[U-Boot] [PATCH] mmc/dw_mmc: Fix clock divider calculation error for bypass mode

[Chin Liang See]

To fix the clock divider calculation error when the controller
clock same as the operating frequency. This is known as bypass
mode. In this mode, the divider should be 0.

Signed-off-by: Chin Liang See <clsee at altera.com>
Cc: Pantelis Antoniou <panto at antoniou-consulting.com>
Cc: Rajeshwari Shinde <rajeshwari.s at samsung.com>
Cc: Jaehoon Chung <jh80.chung at samsung.com>
Cc: Mischa Jonker <mjonker at synopsys.com>
---
 drivers/mmc/dw_mmc.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/dw_mmc.c b/drivers/mmc/dw_mmc.c
index 5bf36a0..0df30bc 100644
--- a/drivers/mmc/dw_mmc.c
+++ b/drivers/mmc/dw_mmc.c
@@ -245,7 +245,10 @@ static int dwmci_setup_bus(struct dwmci_host *host, u32 freq)
 		return -EINVAL;
 	}
 
-	div = DIV_ROUND_UP(sclk, 2 * freq);
+	if (sclk == freq)
+		div = 0;	/* bypass mode */
+	else
+		div = DIV_ROUND_UP(sclk, 2 * freq);
 
 	dwmci_writel(host, DWMCI_CLKENA, 0);
 	dwmci_writel(host, DWMCI_CLKSRC, 0);
-- 
1.7.9.5