tps65090-charger: Fix AC detect

The VACG interrupt was not being enabled.  Thus, interrupts were never
generated when AC status changes.  In addition, interrupts were never
cleared after taking and processing the interrupt.

Added the register offset for the INTR_MASK register, since this is needed
to unmask the VACG interrupt.

Enabled the VACG interrupt in tps65090_config_charger().

Cleared interrupts after processing, in tps65090_charger_isr().

Also removed unused variable "enable" in tps65090_enable_charging(), and
fixed a typo in one of the dev_err() prints.

Signed-off-by: Andrew Chew <achew@nvidia.com>
Tested-by: Rhyland Klein <rklein@nvidia.com>
Acked-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Anton Vorontsov <anton@enomsg.org>

drivers/power/tps65090-charger.c

@@ -27,6 +27,7 @@
 #include <linux/mfd/tps65090.h>
 
 #define TPS65090_REG_INTR_STS	0x00
+#define TPS65090_REG_INTR_MASK	0x02
 #define TPS65090_REG_CG_CTRL0	0x04
 #define TPS65090_REG_CG_CTRL1	0x05
 #define TPS65090_REG_CG_CTRL2	0x06
@@ -67,8 +68,7 @@ static int tps65090_low_chrg_current(struct tps65090_charger *charger)
 	return 0;
 }
 
-static int tps65090_enable_charging(struct tps65090_charger *charger,
-	uint8_t enable)
+static int tps65090_enable_charging(struct tps65090_charger *charger)
 {
 	int ret;
 	uint8_t ctrl0 = 0;
@@ -84,7 +84,7 @@ static int tps65090_enable_charging(struct tps65090_charger *charger,
 	ret = tps65090_write(charger->dev->parent, TPS65090_REG_CG_CTRL0,
 				(ctrl0 | TPS65090_CHARGER_ENABLE));
 	if (ret < 0) {
-		dev_err(charger->dev, "%s(): error reading in register 0x%x\n",
+		dev_err(charger->dev, "%s(): error writing in register 0x%x\n",
 				__func__, TPS65090_REG_CG_CTRL0);
 		return ret;
 	}
@@ -93,6 +93,7 @@ static int tps65090_enable_charging(struct tps65090_charger *charger,
 
 static int tps65090_config_charger(struct tps65090_charger *charger)
 {
+	uint8_t intrmask = 0;
 	int ret;
 
 	if (charger->pdata->enable_low_current_chrg) {
@@ -104,6 +105,23 @@ static int tps65090_config_charger(struct tps65090_charger *charger)
 		}
 	}
 
+	/* Enable the VACG interrupt for AC power detect */
+	ret = tps65090_read(charger->dev->parent, TPS65090_REG_INTR_MASK,
+			    &intrmask);
+	if (ret < 0) {
+		dev_err(charger->dev, "%s(): error reading in register 0x%x\n",
+			__func__, TPS65090_REG_INTR_MASK);
+		return ret;
+	}
+
+	ret = tps65090_write(charger->dev->parent, TPS65090_REG_INTR_MASK,
+			     (intrmask | TPS65090_VACG));
+	if (ret < 0) {
+		dev_err(charger->dev, "%s(): error writing in register 0x%x\n",
+			__func__, TPS65090_REG_CG_CTRL0);
+		return ret;
+	}
+
 	return 0;
 }
 
@@ -146,7 +164,7 @@ static irqreturn_t tps65090_charger_isr(int irq, void *dev_id)
 	}
 
 	if (intrsts & TPS65090_VACG) {
-		ret = tps65090_enable_charging(charger, 1);
+		ret = tps65090_enable_charging(charger);
 		if (ret < 0)
 			return IRQ_HANDLED;
 		charger->ac_online = 1;
@@ -154,6 +172,13 @@ static irqreturn_t tps65090_charger_isr(int irq, void *dev_id)
 		charger->ac_online = 0;
 	}
 
+	/* Clear interrupts. */
+	ret = tps65090_write(charger->dev->parent, TPS65090_REG_INTR_STS, 0x00);
+	if (ret < 0) {
+		dev_err(charger->dev, "%s(): Error in writing reg 0x%x\n",
+				__func__, TPS65090_REG_INTR_STS);
+	}
+
 	if (charger->prev_ac_online != charger->ac_online)
 		power_supply_changed(&charger->ac);
 
@@ -270,7 +295,7 @@ static int tps65090_charger_probe(struct platform_device *pdev)
 	}
 
 	if (status1 != 0) {
-		ret = tps65090_enable_charging(cdata, 1);
+		ret = tps65090_enable_charging(cdata);
 		if (ret < 0) {
 			dev_err(cdata->dev, "error enabling charger\n");
 			goto fail_free_irq;