ASoC: cs42l42: Split cs42l42_resume into two functions

On SoundWire the system resume cannot restore registers until the
host controller has re-enumerated the peripheral.

This patch splits cs42l42_resume() into two functions, one to
power up and the other to restore registers, ready for adding
SoundWire support.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Signed-off-by: Martin Povišer <povik+lin@cutebit.org>
Link: https://lore.kernel.org/r/20220915094444.11434-6-povik+lin@cutebit.orgSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/cs42l42.c

@@ -2184,6 +2184,15 @@ static int __maybe_unused cs42l42_resume(struct device *dev)
 	gpiod_set_value_cansleep(cs42l42->reset_gpio, 1);
 	usleep_range(CS42L42_BOOT_TIME_US, CS42L42_BOOT_TIME_US * 2);
 
+	dev_dbg(dev, "System resume powered up\n");
+
+	return 0;
+}
+
+static void __maybe_unused cs42l42_resume_restore(struct device *dev)
+{
+	struct cs42l42_private *cs42l42 = dev_get_drvdata(dev);
+
 	regcache_cache_only(cs42l42->regmap, false);
 	regcache_mark_dirty(cs42l42->regmap);
 
@@ -2196,6 +2205,17 @@ static int __maybe_unused cs42l42_resume(struct device *dev)
 	mutex_unlock(&cs42l42->irq_lock);
 
 	dev_dbg(dev, "System resumed\n");
+}
+
+static int __maybe_unused cs42l42_i2c_resume(struct device *dev)
+{
+	int ret;
+
+	ret = cs42l42_resume(dev);
+	if (ret)
+		return ret;
+
+	cs42l42_resume_restore(dev);
 
 	return 0;
 }
@@ -2414,7 +2434,7 @@ static int cs42l42_i2c_remove(struct i2c_client *i2c_client)
 }
 
 static const struct dev_pm_ops cs42l42_pm_ops = {
-	SET_SYSTEM_SLEEP_PM_OPS(cs42l42_suspend, cs42l42_resume)
+	SET_SYSTEM_SLEEP_PM_OPS(cs42l42_suspend, cs42l42_i2c_resume)
 };
 
 #ifdef CONFIG_OF