ide: palm_bk3710: test clock rate to avoid division by 0

The clk API may return 0 on clk_get_rate, so we should check the result before
using it as a divisor.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/ide/palm_bk3710.c

@@ -325,6 +325,8 @@ static int __init palm_bk3710_probe(struct platform_device *pdev)
 
 	clk_enable(clk);
 	rate = clk_get_rate(clk);
+	if (!rate)
+		return -EINVAL;
 
 	/* NOTE:  round *down* to meet minimum timings; we count in clocks */
 	ideclk_period = 1000000000UL / rate;