ASoC: tas6424: Add channel fault reporting

The TAS6426 has a register that reports channel faults such as
overcurrent and continuous DC output. Add reporting of this here.
Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/tas6424.c

@@ -41,6 +41,7 @@ struct tas6424_data {
 	struct regmap *regmap;
 	struct regulator_bulk_data supplies[TAS6424_NUM_SUPPLIES];
 	struct delayed_work fault_check_work;
+	unsigned int last_cfault;
 	unsigned int last_fault1;
 	unsigned int last_fault2;
 	unsigned int last_warn;
@@ -406,6 +407,51 @@ static void tas6424_fault_check_work(struct work_struct *work)
 	unsigned int reg;
 	int ret;
 
+	ret = regmap_read(tas6424->regmap, TAS6424_CHANNEL_FAULT, &reg);
+	if (ret < 0) {
+		dev_err(dev, "failed to read CHANNEL_FAULT register: %d\n", ret);
+		goto out;
+	}
+
+	if (!reg) {
+		tas6424->last_cfault = reg;
+		goto check_global_fault1_reg;
+	}
+
+	/*
+	 * Only flag errors once for a given occurrence. This is needed as
+	 * the TAS6424 will take time clearing the fault condition internally
+	 * during which we don't want to bombard the system with the same
+	 * error message over and over.
+	 */
+	if ((reg & TAS6424_FAULT_OC_CH1) && !(tas6424->last_cfault & TAS6424_FAULT_OC_CH1))
+		dev_crit(dev, "experienced a channel 1 overcurrent fault\n");
+
+	if ((reg & TAS6424_FAULT_OC_CH2) && !(tas6424->last_cfault & TAS6424_FAULT_OC_CH2))
+		dev_crit(dev, "experienced a channel 2 overcurrent fault\n");
+
+	if ((reg & TAS6424_FAULT_OC_CH3) && !(tas6424->last_cfault & TAS6424_FAULT_OC_CH3))
+		dev_crit(dev, "experienced a channel 3 overcurrent fault\n");
+
+	if ((reg & TAS6424_FAULT_OC_CH4) && !(tas6424->last_cfault & TAS6424_FAULT_OC_CH4))
+		dev_crit(dev, "experienced a channel 4 overcurrent fault\n");
+
+	if ((reg & TAS6424_FAULT_DC_CH1) && !(tas6424->last_cfault & TAS6424_FAULT_DC_CH1))
+		dev_crit(dev, "experienced a channel 1 DC fault\n");
+
+	if ((reg & TAS6424_FAULT_DC_CH2) && !(tas6424->last_cfault & TAS6424_FAULT_DC_CH2))
+		dev_crit(dev, "experienced a channel 2 DC fault\n");
+
+	if ((reg & TAS6424_FAULT_DC_CH3) && !(tas6424->last_cfault & TAS6424_FAULT_DC_CH3))
+		dev_crit(dev, "experienced a channel 3 DC fault\n");
+
+	if ((reg & TAS6424_FAULT_DC_CH4) && !(tas6424->last_cfault & TAS6424_FAULT_DC_CH4))
+		dev_crit(dev, "experienced a channel 4 DC fault\n");
+
+	/* Store current fault1 value so we can detect any changes next time */
+	tas6424->last_cfault = reg;
+
+check_global_fault1_reg:
 	ret = regmap_read(tas6424->regmap, TAS6424_GLOB_FAULT1, &reg);
 	if (ret < 0) {
 		dev_err(dev, "failed to read GLOB_FAULT1 register: %d\n", ret);
@@ -429,12 +475,6 @@ static void tas6424_fault_check_work(struct work_struct *work)
 		goto check_global_fault2_reg;
 	}
 
-	/*
-	 * Only flag errors once for a given occurrence. This is needed as
-	 * the TAS6424 will take time clearing the fault condition internally
-	 * during which we don't want to bombard the system with the same
-	 * error message over and over.
-	 */
 	if ((reg & TAS6424_FAULT_PVDD_OV) && !(tas6424->last_fault1 & TAS6424_FAULT_PVDD_OV))
 		dev_crit(dev, "experienced a PVDD overvoltage fault\n");
 

sound/soc/codecs/tas6424.h

@@ -115,6 +115,16 @@
 #define TAS6424_LDGBYPASS_SHIFT		0
 #define TAS6424_LDGBYPASS_MASK		BIT(TAS6424_LDGBYPASS_SHIFT)
 
+/* TAS6424_GLOB_FAULT1_REG */
+#define TAS6424_FAULT_OC_CH1		BIT(7)
+#define TAS6424_FAULT_OC_CH2		BIT(6)
+#define TAS6424_FAULT_OC_CH3		BIT(5)
+#define TAS6424_FAULT_OC_CH4		BIT(4)
+#define TAS6424_FAULT_DC_CH1		BIT(3)
+#define TAS6424_FAULT_DC_CH2		BIT(2)
+#define TAS6424_FAULT_DC_CH3		BIT(1)
+#define TAS6424_FAULT_DC_CH4		BIT(0)
+
 /* TAS6424_GLOB_FAULT1_REG */
 #define TAS6424_FAULT_CLOCK		BIT(4)
 #define TAS6424_FAULT_PVDD_OV		BIT(3)