power: supply: bq24190_charger: Clean up extcon code

Polishing and fixes for initial extcon patch.

Fixes: 4db249b6f3b4 ("power: supply: bq24190_charger: Use extcon to determine ilimit, 5v boost")
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Liam Breck <kernel@networkimprov.net>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>

drivers/power/supply/bq24190_charger.c

@@ -38,8 +38,9 @@
 #define BQ24190_REG_POC_WDT_RESET_SHIFT		6
 #define BQ24190_REG_POC_CHG_CONFIG_MASK		(BIT(5) | BIT(4))
 #define BQ24190_REG_POC_CHG_CONFIG_SHIFT	4
-#define BQ24190_REG_POC_CHG_CONFIG_CHARGE	1
-#define BQ24190_REG_POC_CHG_CONFIG_OTG		2
+#define BQ24190_REG_POC_CHG_CONFIG_DISABLE		0x0
+#define BQ24190_REG_POC_CHG_CONFIG_CHARGE		0x1
+#define BQ24190_REG_POC_CHG_CONFIG_OTG			0x2
 #define BQ24190_REG_POC_SYS_MIN_MASK		(BIT(3) | BIT(2) | BIT(1))
 #define BQ24190_REG_POC_SYS_MIN_SHIFT		1
 #define BQ24190_REG_POC_BOOST_LIM_MASK		BIT(0)
@@ -173,8 +174,9 @@ struct bq24190_dev_info {
  */
 
 /* REG00[2:0] (IINLIM) in uAh */
-static const int bq24190_iinlim_values[] = {
-	100000, 150000, 500000, 900000, 1200000, 1500000, 2000000, 3000000 };
+static const int bq24190_isc_iinlim_values[] = {
+	 100000,  150000,  500000,  900000, 1200000, 1500000, 2000000, 3000000
+};
 
 /* REG02[7:2] (ICHG) in uAh */
 static const int bq24190_ccc_ichg_values[] = {
@@ -1298,50 +1300,47 @@ static void bq24190_extcon_work(struct work_struct *work)
 {
 	struct bq24190_dev_info *bdi =
 		container_of(work, struct bq24190_dev_info, extcon_work.work);
-	int ret, iinlim = 0;
+	int error, iinlim = 0;
+	u8 v;
 
-	ret = pm_runtime_get_sync(bdi->dev);
-	if (ret < 0) {
-		dev_err(bdi->dev, "Error getting runtime-pm ref: %d\n", ret);
+	error = pm_runtime_get_sync(bdi->dev);
+	if (error < 0) {
+		dev_warn(bdi->dev, "pm_runtime_get failed: %i\n", error);
+		pm_runtime_put_noidle(bdi->dev);
 		return;
 	}
 
-	if (extcon_get_state(bdi->extcon, EXTCON_CHG_USB_SDP) == 1)
-		iinlim = 500000;
+	if      (extcon_get_state(bdi->extcon, EXTCON_CHG_USB_SDP) == 1)
+		iinlim =  500000;
 	else if (extcon_get_state(bdi->extcon, EXTCON_CHG_USB_CDP) == 1 ||
 		 extcon_get_state(bdi->extcon, EXTCON_CHG_USB_ACA) == 1)
 		iinlim = 1500000;
 	else if (extcon_get_state(bdi->extcon, EXTCON_CHG_USB_DCP) == 1)
 		iinlim = 2000000;
 
 	if (iinlim) {
-		ret = bq24190_set_field_val(bdi, BQ24190_REG_ISC,
-				BQ24190_REG_ISC_IINLIM_MASK,
-				BQ24190_REG_ISC_IINLIM_SHIFT,
-				bq24190_iinlim_values,
-				ARRAY_SIZE(bq24190_iinlim_values),
-				iinlim);
-		if (ret)
-			dev_err(bdi->dev, "Can't set IINLIM: %d\n", ret);
+		error = bq24190_set_field_val(bdi, BQ24190_REG_ISC,
+					      BQ24190_REG_ISC_IINLIM_MASK,
+					      BQ24190_REG_ISC_IINLIM_SHIFT,
+					      bq24190_isc_iinlim_values,
+					      ARRAY_SIZE(bq24190_isc_iinlim_values),
+					      iinlim);
+		if (error < 0)
+			dev_err(bdi->dev, "Can't set IINLIM: %d\n", error);
 	}
 
-	/*
-	 * If no charger has been detected and host mode is requested, activate
-	 * the 5V boost converter, otherwise deactivate it.
-	 */
-	if (!iinlim && extcon_get_state(bdi->extcon, EXTCON_USB_HOST) == 1) {
-		ret = bq24190_write_mask(bdi, BQ24190_REG_POC,
-					 BQ24190_REG_POC_CHG_CONFIG_MASK,
-					 BQ24190_REG_POC_CHG_CONFIG_SHIFT,
-					 BQ24190_REG_POC_CHG_CONFIG_OTG);
-	} else {
-		ret = bq24190_write_mask(bdi, BQ24190_REG_POC,
-					 BQ24190_REG_POC_CHG_CONFIG_MASK,
-					 BQ24190_REG_POC_CHG_CONFIG_SHIFT,
-					 BQ24190_REG_POC_CHG_CONFIG_CHARGE);
-	}
-	if (ret)
-		dev_err(bdi->dev, "Can't set CHG_CONFIG: %d\n", ret);
+	/* if no charger found and in USB host mode, set OTG 5V boost, else normal */
+	if (!iinlim && extcon_get_state(bdi->extcon, EXTCON_USB_HOST) == 1)
+		v = BQ24190_REG_POC_CHG_CONFIG_OTG;
+	else
+		v = BQ24190_REG_POC_CHG_CONFIG_CHARGE;
+
+	error = bq24190_write_mask(bdi, BQ24190_REG_POC,
+				   BQ24190_REG_POC_CHG_CONFIG_MASK,
+				   BQ24190_REG_POC_CHG_CONFIG_SHIFT,
+				   v);
+	if (error < 0)
+		dev_err(bdi->dev, "Can't set CHG_CONFIG: %d\n", error);
 
 	pm_runtime_mark_last_busy(bdi->dev);
 	pm_runtime_put_autosuspend(bdi->dev);
@@ -1432,8 +1431,15 @@ static int bq24190_probe(struct i2c_client *client,
 	}
 
 	/*
-	 * The extcon-name property is purely an in kernel interface for
-	 * x86/ACPI use, DT platforms should get extcon via phandle.
+	 * Devicetree platforms should get extcon via phandle (not yet supported).
+	 * On ACPI platforms, extcon clients may invoke us with:
+	 * struct property_entry pe[] =
+	 *   { PROPERTY_ENTRY_STRING("extcon-name", client_name), ... };
+	 * struct i2c_board_info bi =
+	 *   { .type = "bq24190", .addr = 0x6b, .properties = pe, .irq = irq };
+	 * struct i2c_adapter ad = { ... };
+	 * i2c_add_adapter(&ad);
+	 * i2c_new_device(&ad, &bi);
 	 */
 	if (device_property_read_string(dev, "extcon-name", &name) == 0) {
 		bdi->extcon = extcon_get_extcon_dev(name);
@@ -1498,8 +1504,10 @@ static int bq24190_probe(struct i2c_client *client,
 		bdi->extcon_nb.notifier_call = bq24190_extcon_event;
 		ret = devm_extcon_register_notifier(dev, bdi->extcon, -1,
 						    &bdi->extcon_nb);
-		if (ret)
+		if (ret) {
+			dev_err(dev, "Can't register extcon\n");
 			goto out5;
+		}
 
 		/* Sync initial cable state */
 		queue_delayed_work(system_wq, &bdi->extcon_work, 0);