ASoC: cs35l35: Allow user to configure IMON SCALE

On the chip the IMON signal is a full 24-bits however normally only
some of the bits will be sent over the bus. The chip provides a field
to select which bits of the IMON will be sent back, this is the only
feedback signal that has this feature.

Add an additional entry to the cirrus,imon device tree property to
allow the IMON scale parameter to be passed.
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Brian Austin <brian.austin@cirrus.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/cs35l35.txt

@@ -118,8 +118,8 @@ Optional Monitor Signal Format sub-node:
   Sections 7.44 - 7.53 lists values for the depth, location, and frame
   for each monitoring signal.
 
-  - cirrus,imon : 3 8 bit values to set the depth, location, and frame
-  of the IMON monitor signal.
+  - cirrus,imon : 4 8 bit values to set the depth, location, frame and ADC
+  scale of the IMON monitor signal.
 
   - cirrus,vmon : 3 8 bit values to set the depth, location, and frame
   of the VMON monitor signal.

include/sound/cs35l35.h

@@ -57,6 +57,7 @@ struct monitor_cfg {
 	u8 imon_dpth;
 	u8 imon_loc;
 	u8 imon_frm;
+	u8 imon_scale;
 	u8 vmon_dpth;
 	u8 vmon_loc;
 	u8 vmon_frm;

sound/soc/codecs/cs35l35.c

@@ -918,6 +918,11 @@ static int cs35l35_codec_probe(struct snd_soc_codec *codec)
 					CS35L35_MON_FRM_MASK,
 					monitor_config->imon_frm <<
 					CS35L35_MON_FRM_SHIFT);
+			regmap_update_bits(cs35l35->regmap,
+					CS35L35_IMON_SCALE_CTL,
+					CS35L35_IMON_SCALE_MASK,
+					monitor_config->imon_scale <<
+					CS35L35_IMON_SCALE_SHIFT);
 		}
 		if (monitor_config->vpmon_specs) {
 			regmap_update_bits(cs35l35->regmap,
@@ -1161,7 +1166,9 @@ static int cs35l35_handle_of_data(struct i2c_client *i2c_client,
 	struct classh_cfg *classh_config = &pdata->classh_algo;
 	struct monitor_cfg *monitor_config = &pdata->mon_cfg;
 	unsigned int val32 = 0;
-	u8 monitor_array[3];
+	u8 monitor_array[4];
+	const int imon_array_size = ARRAY_SIZE(monitor_array);
+	const int mon_array_size = imon_array_size - 1;
 	int ret = 0;
 
 	if (!np)
@@ -1302,15 +1309,16 @@ static int cs35l35_handle_of_data(struct i2c_client *i2c_client,
 	monitor_config->is_present = signal_format ? true : false;
 	if (monitor_config->is_present) {
 		ret = of_property_read_u8_array(signal_format, "cirrus,imon",
-				   monitor_array, ARRAY_SIZE(monitor_array));
+						monitor_array, imon_array_size);
 		if (!ret) {
 			monitor_config->imon_specs = true;
 			monitor_config->imon_dpth = monitor_array[0];
 			monitor_config->imon_loc = monitor_array[1];
 			monitor_config->imon_frm = monitor_array[2];
+			monitor_config->imon_scale = monitor_array[3];
 		}
 		ret = of_property_read_u8_array(signal_format, "cirrus,vmon",
-				   monitor_array, ARRAY_SIZE(monitor_array));
+						monitor_array, mon_array_size);
 		if (!ret) {
 			monitor_config->vmon_specs = true;
 			monitor_config->vmon_dpth = monitor_array[0];
@@ -1318,7 +1326,7 @@ static int cs35l35_handle_of_data(struct i2c_client *i2c_client,
 			monitor_config->vmon_frm = monitor_array[2];
 		}
 		ret = of_property_read_u8_array(signal_format, "cirrus,vpmon",
-				   monitor_array, ARRAY_SIZE(monitor_array));
+						monitor_array, mon_array_size);
 		if (!ret) {
 			monitor_config->vpmon_specs = true;
 			monitor_config->vpmon_dpth = monitor_array[0];
@@ -1326,7 +1334,7 @@ static int cs35l35_handle_of_data(struct i2c_client *i2c_client,
 			monitor_config->vpmon_frm = monitor_array[2];
 		}
 		ret = of_property_read_u8_array(signal_format, "cirrus,vbstmon",
-				   monitor_array, ARRAY_SIZE(monitor_array));
+						monitor_array, mon_array_size);
 		if (!ret) {
 			monitor_config->vbstmon_specs = true;
 			monitor_config->vbstmon_dpth = monitor_array[0];
@@ -1334,7 +1342,7 @@ static int cs35l35_handle_of_data(struct i2c_client *i2c_client,
 			monitor_config->vbstmon_frm = monitor_array[2];
 		}
 		ret = of_property_read_u8_array(signal_format, "cirrus,vpbrstat",
-				   monitor_array, ARRAY_SIZE(monitor_array));
+						monitor_array, mon_array_size);
 		if (!ret) {
 			monitor_config->vpbrstat_specs = true;
 			monitor_config->vpbrstat_dpth = monitor_array[0];
@@ -1342,7 +1350,7 @@ static int cs35l35_handle_of_data(struct i2c_client *i2c_client,
 			monitor_config->vpbrstat_frm = monitor_array[2];
 		}
 		ret = of_property_read_u8_array(signal_format, "cirrus,zerofill",
-				   monitor_array, ARRAY_SIZE(monitor_array));
+						monitor_array, mon_array_size);
 		if (!ret) {
 			monitor_config->zerofill_specs = true;
 			monitor_config->zerofill_dpth = monitor_array[0];

sound/soc/codecs/cs35l35.h

@@ -148,6 +148,9 @@
 #define CS35L35_MON_FRM_MASK		0x80
 #define CS35L35_MON_FRM_SHIFT		7
 
+#define CS35L35_IMON_SCALE_MASK		0xF8
+#define CS35L35_IMON_SCALE_SHIFT	3
+
 #define CS35L35_MS_MASK			0x80
 #define CS35L35_MS_SHIFT		7
 #define CS35L35_SPMODE_MASK		0x40