ASoC: cs35l56: Update ACPI HID and property

Merge series from Richard Fitzgerald <rf@opensource.cirrus.com>:

These two patches add an ACPI HID and update the way the platform-
specific firmware identifier is extracted from the ACPI.

sound/soc/codecs/cs35l56-i2c.c

@@ -62,10 +62,19 @@ static const struct i2c_device_id cs35l56_id_i2c[] = {
 };
 MODULE_DEVICE_TABLE(i2c, cs35l56_id_i2c);
 
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id cs35l56_asoc_acpi_match[] = {
+	{ "CSC355C", 0 },
+	{},
+};
+MODULE_DEVICE_TABLE(acpi, cs35l56_asoc_acpi_match);
+#endif
+
 static struct i2c_driver cs35l56_i2c_driver = {
 	.driver = {
 		.name		= "cs35l56",
 		.pm = &cs35l56_pm_ops_i2c_spi,
+		.acpi_match_table = ACPI_PTR(cs35l56_asoc_acpi_match),
 	},
 	.id_table	= cs35l56_id_i2c,
 	.probe		= cs35l56_i2c_probe,

sound/soc/codecs/cs35l56-spi.c

@@ -59,10 +59,19 @@ static const struct spi_device_id cs35l56_id_spi[] = {
 };
 MODULE_DEVICE_TABLE(spi, cs35l56_id_spi);
 
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id cs35l56_asoc_acpi_match[] = {
+	{ "CSC355C", 0 },
+	{},
+};
+MODULE_DEVICE_TABLE(acpi, cs35l56_asoc_acpi_match);
+#endif
+
 static struct spi_driver cs35l56_spi_driver = {
 	.driver = {
 		.name		= "cs35l56",
 		.pm = &cs35l56_pm_ops_i2c_spi,
+		.acpi_match_table = ACPI_PTR(cs35l56_asoc_acpi_match),
 	},
 	.id_table	= cs35l56_id_spi,
 	.probe		= cs35l56_spi_probe,

sound/soc/codecs/cs35l56.c

@@ -5,7 +5,6 @@
 // Copyright (C) 2023 Cirrus Logic, Inc. and
 //                    Cirrus Logic International Semiconductor Ltd.
 
-#include <linux/acpi.h>
 #include <linux/completion.h>
 #include <linux/debugfs.h>
 #include <linux/delay.h>
@@ -1354,26 +1353,22 @@ static int cs35l56_dsp_init(struct cs35l56_private *cs35l56)
 	return 0;
 }
 
-static int cs35l56_acpi_get_name(struct cs35l56_private *cs35l56)
+static int cs35l56_get_firmware_uid(struct cs35l56_private *cs35l56)
 {
-	acpi_handle handle = ACPI_HANDLE(cs35l56->dev);
-	const char *sub;
+	struct device *dev = cs35l56->dev;
+	const char *prop;
+	int ret;
 
-	/* If there is no ACPI_HANDLE, there is no ACPI for this system, return 0 */
-	if (!handle)
+	ret = device_property_read_string(dev, "cirrus,firmware-uid", &prop);
+	/* If bad sw node property, return 0 and fallback to legacy firmware path */
+	if (ret < 0)
 		return 0;
 
-	sub = acpi_get_subsystem_id(handle);
-	if (IS_ERR(sub)) {
-		/* If bad ACPI, return 0 and fallback to legacy firmware path, otherwise fail */
-		if (PTR_ERR(sub) == -ENODATA)
-			return 0;
-		else
-			return PTR_ERR(sub);
-	}
+	cs35l56->dsp.system_name = devm_kstrdup(dev, prop, GFP_KERNEL);
+	if (cs35l56->dsp.system_name == NULL)
+		return -ENOMEM;
 
-	cs35l56->dsp.system_name = sub;
-	dev_dbg(cs35l56->dev, "Subsystem ID: %s\n", cs35l56->dsp.system_name);
+	dev_dbg(dev, "Firmware UID: %s\n", cs35l56->dsp.system_name);
 
 	return 0;
 }
@@ -1417,7 +1412,7 @@ int cs35l56_common_probe(struct cs35l56_private *cs35l56)
 		gpiod_set_value_cansleep(cs35l56->reset_gpio, 1);
 	}
 
-	ret = cs35l56_acpi_get_name(cs35l56);
+	ret = cs35l56_get_firmware_uid(cs35l56);
 	if (ret != 0)
 		goto err;
 
@@ -1604,8 +1599,6 @@ void cs35l56_remove(struct cs35l56_private *cs35l56)
 
 	regcache_cache_only(cs35l56->regmap, true);
 
-	kfree(cs35l56->dsp.system_name);
-
 	gpiod_set_value_cansleep(cs35l56->reset_gpio, 0);
 	regulator_bulk_disable(ARRAY_SIZE(cs35l56->supplies), cs35l56->supplies);
 }