[U-Boot] [PATCH 1/1] mmc: avoid division by zero in meson_mmc_config_clock

[Heinrich Schuchardt]

The Odroid C2 fails to read from mmc with U-Boot v2018.03.
The change avoids a division by zero.

The fix was suggested by Jaehoon in
https://lists.denx.de/pipermail/u-boot/2018-January/318577.html

Reported-by: Vagrant Cascadian <vagrant at debian.org>
Suggested-by: Jaehoon Chung <jh80.chung at samsung.com>
Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
---
Resent due to missing cc u-boot at lists.denx.de.
---
 drivers/mmc/meson_gx_mmc.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/mmc/meson_gx_mmc.c b/drivers/mmc/meson_gx_mmc.c
index a2cd5d3a44..454593eec4 100644
--- a/drivers/mmc/meson_gx_mmc.c
+++ b/drivers/mmc/meson_gx_mmc.c
@@ -35,6 +35,9 @@ static void meson_mmc_config_clock(struct mmc *mmc)
 	uint32_t meson_mmc_clk = 0;
 	unsigned int clk, clk_src, clk_div;
 
+	if (!mmc->clock)
+		return;
+
 	/* 1GHz / CLK_MAX_DIV = 15,9 MHz */
 	if (mmc->clock > 16000000) {
 		clk = SD_EMMC_CLKSRC_DIV2;
-- 
2.14.2