mfd: Also restore wm8994 GPIO IRQ masks after reset

This ensures that if we are using a GPIO as a wake source it continues to
function while we're suspended.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/wm8994-core.c b/drivers/mfd/wm8994-core.c
index 53293c7..eec74aa 100644
--- a/drivers/mfd/wm8994-core.c
+++ b/drivers/mfd/wm8994-core.c
@@ -293,6 +293,13 @@
 	if (ret != 0)
 		dev_err(dev, "Failed to restore GPIO registers: %d\n", ret);
 
+	/* In case one of the GPIOs is used as a wake input. */
+	ret = regcache_sync_region(wm8994->regmap,
+				   WM8994_INTERRUPT_STATUS_1_MASK,
+				   WM8994_INTERRUPT_STATUS_1_MASK);
+	if (ret != 0)
+		dev_err(dev, "Failed to restore interrupt mask: %d\n", ret);
+
 	regcache_cache_only(wm8994->regmap, true);
 	wm8994->suspended = true;