hwrng: omap3-rom - Handle return value of clk_prepare_enable

Here, Clock enable can failed. So adding an error check for
clk_prepare_enable.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/char/hw_random/omap3-rom-rng.c

@@ -53,7 +53,10 @@ static int omap3_rom_rng_get_random(void *buf, unsigned int count)
 
 	cancel_delayed_work_sync(&idle_work);
 	if (rng_idle) {
-		clk_prepare_enable(rng_clk);
+		r = clk_prepare_enable(rng_clk);
+		if (r)
+			return r;
+
 		r = omap3_rom_rng_call(0, 0, RNG_GEN_PRNG_HW_INIT);
 		if (r != 0) {
 			clk_disable_unprepare(rng_clk);
@@ -88,6 +91,8 @@ static struct hwrng omap3_rom_rng_ops = {
 
 static int omap3_rom_rng_probe(struct platform_device *pdev)
 {
+	int ret = 0;
+
 	pr_info("initializing\n");
 
 	omap3_rom_rng_call = pdev->dev.platform_data;
@@ -104,7 +109,9 @@ static int omap3_rom_rng_probe(struct platform_device *pdev)
 	}
 
 	/* Leave the RNG in reset state. */
-	clk_prepare_enable(rng_clk);
+	ret = clk_prepare_enable(rng_clk);
+	if (ret)
+		return ret;
 	omap3_rom_rng_idle(0);
 
 	return hwrng_register(&omap3_rom_rng_ops);