From: Heinrich Schuchardt <xypron.glpk@gmx.de>
Date: Sat, 17 Mar 2018 22:49:36 +0000 (+0000)
Subject: mmc: avoid division by zero in meson_mmc_config_clock
X-Git-Tag: v2018.05-rc3~45
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=f6549c85410668e73503221ce6147d049cc6251d;p=oweals%2Fu-boot.git

mmc: avoid division by zero in meson_mmc_config_clock

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@debian.org>
Suggested-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Tested-by: Vagrant Cascadian <vagrant@debian.org>
---

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;