ASoC: tas2764: Configure zeroing of SDOUT slots

The codec has an option to zero out certain TDM slots on its SDOUT
output according to a preconfigured mask (otherwise the output is, for
the duration of unused slots, in a Hi-Z state). Configure this feature
based on a mask read from the devicetree.

Signed-off-by: Martin Povišer <povik+lin@cutebit.org>

Author: povik

sound/soc/codecs/tas2764.c

@@ -41,6 +41,7 @@ struct tas2764_priv {
 
 	int v_sense_slot;
 	int i_sense_slot;
+	u32 sdout_zero_mask;
 
 	bool dac_powered;
 	bool unmuted;
@@ -692,6 +693,23 @@ static int tas2764_codec_probe(struct snd_soc_component *component)
 
 	switch (tas2764->devid) {
 	case DEVID_SN012776:
+		if (tas2764->sdout_zero_mask) {
+			for (i = 0; i < 4; i++) {
+				ret = snd_soc_component_write(component, TAS2764_SDOUT_HIZ_1 + i,
+							(tas2764->sdout_zero_mask >> (i * 8)) & 0xff);
+
+				if (ret < 0)
+					return ret;
+			}
+
+			ret = snd_soc_component_update_bits(component, TAS2764_SDOUT_HIZ_9,
+							TAS2764_SDOUT_HIZ_9_FORCE_0_EN,
+							TAS2764_SDOUT_HIZ_9_FORCE_0_EN);
+
+			if (ret < 0)
+				return ret;
+		}
+
 		ret = snd_soc_component_update_bits(component, TAS2764_PWR_CTRL,
 					TAS2764_PWR_CTRL_BOP_SRC,
 					TAS2764_PWR_CTRL_BOP_SRC);
@@ -848,6 +866,11 @@ static int tas2764_parse_dt(struct device *dev, struct tas2764_priv *tas2764)
 	if (ret)
 		tas2764->v_sense_slot = -1;
 
+	ret = fwnode_property_read_u32(dev->fwnode, "ti,sdout-force-zero-mask",
+				       &tas2764->sdout_zero_mask);
+	if (ret)
+		tas2764->sdout_zero_mask = 0;
+
 	return 0;
 }
 

sound/soc/codecs/tas2764.h

@@ -126,4 +126,15 @@
 
 #define TAS2764_BOP_CFG0                TAS2764_REG(0X0, 0x1d)
 
+#define TAS2764_SDOUT_HIZ_1		TAS2764_REG(0x1, 0x3d)
+#define TAS2764_SDOUT_HIZ_2		TAS2764_REG(0x1, 0x3e)
+#define TAS2764_SDOUT_HIZ_3		TAS2764_REG(0x1, 0x3f)
+#define TAS2764_SDOUT_HIZ_4		TAS2764_REG(0x1, 0x40)
+#define TAS2764_SDOUT_HIZ_5		TAS2764_REG(0x1, 0x41)
+#define TAS2764_SDOUT_HIZ_6		TAS2764_REG(0x1, 0x42)
+#define TAS2764_SDOUT_HIZ_7		TAS2764_REG(0x1, 0x43)
+#define TAS2764_SDOUT_HIZ_8		TAS2764_REG(0x1, 0x44)
+#define TAS2764_SDOUT_HIZ_9		TAS2764_REG(0x1, 0x45)
+#define TAS2764_SDOUT_HIZ_9_FORCE_0_EN	BIT(7)
+
 #endif /* __TAS2764__ */