ASoC: wm8782: Use wlf,fsampen device tree property

The wm8782 supports rates 96kHz and 192kHz as long as the hardware
is configured properly. Allow this to be specified in the device tree.
Signed-off-by: John Watts <contact@jookia.org>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20230918131532.2257615-3-contact@jookia.orgSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/wm8782.c

@@ -119,8 +119,9 @@ static const struct snd_soc_component_driver soc_component_dev_wm8782 = {
 static int wm8782_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
 	struct wm8782_priv *priv;
-	int ret, i;
+	int ret, i, fsampen;
 
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
@@ -136,8 +137,26 @@ static int wm8782_probe(struct platform_device *pdev)
 	if (ret < 0)
 		return ret;
 
-	/* For configurations with FSAMPEN=0 */
-	priv->max_rate = 48000;
+	// Assume lowest value by default to avoid inadvertent overclocking
+	fsampen = 0;
+
+	if (np)
+		of_property_read_u32(np, "wlf,fsampen", &fsampen);
+
+	switch (fsampen) {
+	case 0:
+		priv->max_rate = 48000;
+		break;
+	case 1:
+		priv->max_rate = 96000;
+		break;
+	case 2:
+		priv->max_rate = 192000;
+		break;
+	default:
+		dev_err(dev, "Invalid wlf,fsampen value");
+		return -EINVAL;
+	}
 
 	return devm_snd_soc_register_component(&pdev->dev,
 			&soc_component_dev_wm8782, &wm8782_dai, 1);