diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 2ac0b68..4b97d52 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -616,6 +616,9 @@
 		target_timeout = data->timeout_ns / 1000 +
 			data->timeout_clks / host->clock;
 
+	if (host->quirks & SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK)
+		host->timeout_clk = host->clock / 1000;
+
 	/*
 	 * Figure out needed cycles.
 	 * We do this in steps in order to fit inside a 32 bit int.
@@ -626,6 +629,7 @@
 	 *     =>
 	 *     (1) / (2) > 2^6
 	 */
+	BUG_ON(!host->timeout_clk);
 	count = 0;
 	current_timeout = (1 << 13) * 1000 / host->timeout_clk;
 	while (current_timeout < target_timeout) {
@@ -1901,9 +1905,6 @@
 	if (caps & SDHCI_TIMEOUT_CLK_UNIT)
 		host->timeout_clk *= 1000;
 
-	if (host->quirks & SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK)
-		host->timeout_clk = host->clock / 1000;
-
 	/*
 	 * Set host parameters.
 	 */