counter: stm32-timer-cnt: Add check for clk_enable()

Add check for the return value of clk_enable() in order to catch the
potential exception.

Fixes: c5b8425 ("counter: stm32-timer-cnt: add power management support")
Fixes: ad29937 ("counter: Add STM32 Timer quadrature encoder")
Signed-off-by: Jiasheng Jiang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: William Breathitt Gray <[email protected]>

Author: Jiasheng Jiang

drivers/counter/stm32-timer-cnt.c

@@ -214,11 +214,17 @@ static int stm32_count_enable_write(struct counter_device *counter,
 {
 	struct stm32_timer_cnt *const priv = counter_priv(counter);
 	u32 cr1;
+	int ret;
 
 	if (enable) {
 		regmap_read(priv->regmap, TIM_CR1, &cr1);
-		if (!(cr1 & TIM_CR1_CEN))
-			clk_enable(priv->clk);
+		if (!(cr1 & TIM_CR1_CEN)) {
+			ret = clk_enable(priv->clk);
+			if (ret) {
+				dev_err(counter->parent, "Cannot enable clock %d\n", ret);
+				return ret;
+			}
+		}
 
 		regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN,
 				   TIM_CR1_CEN);
@@ -817,7 +823,11 @@ static int __maybe_unused stm32_timer_cnt_resume(struct device *dev)
 		return ret;
 
 	if (priv->enabled) {
-		clk_enable(priv->clk);
+		ret = clk_enable(priv->clk);
+		if (ret) {
+			dev_err(dev, "Cannot enable clock %d\n", ret);
+			return ret;
+		}
 
 		/* Restore registers that may have been lost */
 		regmap_write(priv->regmap, TIM_SMCR, priv->bak.smcr);