[PATCH v3 1/3] ASoC: wm8782: Constrain maximum audio rate at runtime

[John Watts]

The wm8782 supports up to 192kHz audio when pins are set correctly.
Instead of hardcoding which rates are supported constrain them at
runtime based on a max_rate variable.

Signed-off-by: John Watts <contact@xxxxxxxxxx>
---
 sound/soc/codecs/wm8782.c | 42 ++++++++++++++++++++++++++++-----------
 1 file changed, 30 insertions(+), 12 deletions(-)

diff --git a/sound/soc/codecs/wm8782.c b/sound/soc/codecs/wm8782.c
index 95ff4339d103..f3dc87b92b1e 100644
--- a/sound/soc/codecs/wm8782.c
+++ b/sound/soc/codecs/wm8782.c
@@ -23,6 +23,27 @@
 #include <sound/initval.h>
 #include <sound/soc.h>
 
+/* regulator power supply names */
+static const char *supply_names[] = {
+	"Vdda", /* analog supply, 2.7V - 3.6V */
+	"Vdd",  /* digital supply, 2.7V - 5.5V */
+};
+
+struct wm8782_priv {
+	struct regulator_bulk_data supplies[ARRAY_SIZE(supply_names)];
+	int max_rate;
+};
+
+static int wm8782_dai_startup(struct snd_pcm_substream *sub, struct snd_soc_dai *dai)
+{
+	struct snd_pcm_runtime *runtime = sub->runtime;
+	struct wm8782_priv *priv =
+		snd_soc_component_get_drvdata(dai->component);
+
+	return snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_RATE,
+					   8000, priv->max_rate);
+}
+
 static const struct snd_soc_dapm_widget wm8782_dapm_widgets[] = {
 SND_SOC_DAPM_INPUT("AINL"),
 SND_SOC_DAPM_INPUT("AINR"),
@@ -33,28 +54,22 @@ static const struct snd_soc_dapm_route wm8782_dapm_routes[] = {
 	{ "Capture", NULL, "AINR" },
 };
 
+static const struct snd_soc_dai_ops wm8782_dai_ops = {
+	.startup = &wm8782_dai_startup,
+};
+
 static struct snd_soc_dai_driver wm8782_dai = {
 	.name = "wm8782",
 	.capture = {
 		.stream_name = "Capture",
 		.channels_min = 2,
 		.channels_max = 2,
-		/* For configurations with FSAMPEN=0 */
-		.rates = SNDRV_PCM_RATE_8000_48000,
+		.rates = SNDRV_PCM_RATE_8000_192000,
 		.formats = SNDRV_PCM_FMTBIT_S16_LE |
 			   SNDRV_PCM_FMTBIT_S20_3LE |
 			   SNDRV_PCM_FMTBIT_S24_LE,
 	},
-};
-
-/* regulator power supply names */
-static const char *supply_names[] = {
-	"Vdda", /* analog supply, 2.7V - 3.6V */
-	"Vdd",  /* digital supply, 2.7V - 5.5V */
-};
-
-struct wm8782_priv {
-	struct regulator_bulk_data supplies[ARRAY_SIZE(supply_names)];
+	.ops = &wm8782_dai_ops,
 };
 
 static int wm8782_soc_probe(struct snd_soc_component *component)
@@ -121,6 +136,9 @@ static int wm8782_probe(struct platform_device *pdev)
 	if (ret < 0)
 		return ret;
 
+	/* For configurations with FSAMPEN=0 */
+	priv->max_rate = 48000;
+
 	return devm_snd_soc_register_component(&pdev->dev,
 			&soc_component_dev_wm8782, &wm8782_dai, 1);
 }
-- 
2.42.0