ASoC: wm8962: Hold a runtime PM reference while handling interrupts

If the device is runtime suspended then we can't interact with it as it
may have been powered off and the register map will be in cache only
mode.
Signed-off-by: Mark Brown <broonie@linaro.org>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>

sound/soc/codecs/wm8962.c

@@ -3003,9 +3003,16 @@ static irqreturn_t wm8962_irq(int irq, void *data)
 	unsigned int active;
 	int reg, ret;
 
+	ret = pm_runtime_get_sync(dev);
+	if (ret < 0) {
+		dev_err(dev, "Failed to resume: %d\n", ret);
+		return IRQ_NONE;
+	}
+
 	ret = regmap_read(wm8962->regmap, WM8962_INTERRUPT_STATUS_2_MASK,
 			  &mask);
 	if (ret != 0) {
+		pm_runtime_put(dev);
 		dev_err(dev, "Failed to read interrupt mask: %d\n",
 			ret);
 		return IRQ_NONE;
@@ -3013,14 +3020,17 @@ static irqreturn_t wm8962_irq(int irq, void *data)
 
 	ret = regmap_read(wm8962->regmap, WM8962_INTERRUPT_STATUS_2, &active);
 	if (ret != 0) {
+		pm_runtime_put(dev);
 		dev_err(dev, "Failed to read interrupt: %d\n", ret);
 		return IRQ_NONE;
 	}
 
 	active &= ~mask;
 
-	if (!active)
+	if (!active) {
+		pm_runtime_put(dev);
 		return IRQ_NONE;
+	}
 
 	/* Acknowledge the interrupts */
 	ret = regmap_write(wm8962->regmap, WM8962_INTERRUPT_STATUS_2, active);
@@ -3070,6 +3080,8 @@ static irqreturn_t wm8962_irq(int irq, void *data)
 				   msecs_to_jiffies(250));
 	}
 
+	pm_runtime_put(dev);
+
 	return IRQ_HANDLED;
 }