ASoC: cs35l35: Add for configuring drive mode in unused slots

Add support for setting how the I2S pins are driven in unused slots,
currently the chip will just use the default of drive 0, however this
causes issues when multiple devices are attached to the same bus.
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Brian Austin <brian.austin@cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

include/sound/cs35l35.h

@@ -80,6 +80,8 @@ struct cs35l35_platform_data {
 	bool stereo;
 	/* serial port drive strength */
 	int sp_drv_str;
+	/* serial port drive in unused slots */
+	int sp_drv_unused;
 	/* Boost Power Down with FET */
 	bool bst_pdn_fet_on;
 	/* Boost Voltage : used if ClassH Algo Enabled */

sound/soc/codecs/cs35l35.c

@@ -789,6 +789,11 @@ static int cs35l35_codec_probe(struct snd_soc_codec *codec)
 				CS35L35_SP_DRV_MASK,
 				cs35l35->pdata.sp_drv_str <<
 				CS35L35_SP_DRV_SHIFT);
+	if (cs35l35->pdata.sp_drv_unused)
+		regmap_update_bits(cs35l35->regmap, CS35L35_SP_FMT_CTL3,
+				   CS35L35_SP_I2S_DRV_MASK,
+				   cs35l35->pdata.sp_drv_unused <<
+				   CS35L35_SP_I2S_DRV_SHIFT);
 
 	if (classh->classh_algo_enable) {
 		if (classh->classh_bst_override)
@@ -1169,6 +1174,8 @@ static int cs35l35_handle_of_data(struct i2c_client *i2c_client,
 
 	if (of_property_read_u32(np, "cirrus,sp-drv-strength", &val32) >= 0)
 		pdata->sp_drv_str = val32;
+	if (of_property_read_u32(np, "cirrus,sp-drv-unused", &val32) >= 0)
+		pdata->sp_drv_unused = val32 | CS35L35_VALID_PDATA;
 
 	pdata->stereo = of_property_read_bool(np, "cirrus,stereo-config");
 

sound/soc/codecs/cs35l35.h

@@ -190,6 +190,10 @@
 #define CS35L35_AMP_GAIN_ZC_MASK	0x10
 #define CS35L35_AMP_GAIN_ZC_SHIFT	4
 
+/* CS35L35_SP_FMT_CTL3 */
+#define CS35L35_SP_I2S_DRV_MASK		0x03
+#define CS35L35_SP_I2S_DRV_SHIFT	0
+
 /* Class H Algorithm Control */
 #define CS35L35_CH_STEREO_MASK		0x40
 #define CS35L35_CH_STEREO_SHIFT		6