extcon: ptn5150: Check current USB mode when probing

When machine boots up, the USB could be already in OTG mode.  In such
case there will be no interrupt coming to ptn5150 device and driver will
report default state of nothing connected.  Detection of USB connection
would happen on first unplug of the cable.

Factor out code for checking current connection mode and call it right
after probe so the existing USB mode will be properly reported.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Vijai Kumar K <vijaikumar.kanagarajan@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>

drivers/extcon/extcon-ptn5150.c

@@ -5,6 +5,7 @@
 // Based on extcon-sm5502.c driver
 // Copyright (c) 2018-2019 by Vijai Kumar K
 // Author: Vijai Kumar K <vijaikumar.kanagarajan@gmail.com>
+// Copyright (c) 2020 Krzysztof Kozlowski <krzk@kernel.org>
 
 #include <linux/err.h>
 #include <linux/i2c.h>
@@ -83,12 +84,49 @@ static const struct regmap_config ptn5150_regmap_config = {
 	.max_register	= PTN5150_REG_END,
 };
 
+static void ptn5150_check_state(struct ptn5150_info *info)
+{
+	unsigned int port_status, reg_data, vbus;
+	int ret;
+
+	ret = regmap_read(info->regmap, PTN5150_REG_CC_STATUS, &reg_data);
+	if (ret) {
+		dev_err(info->dev, "failed to read CC STATUS %d\n", ret);
+		return;
+	}
+
+	port_status = ((reg_data &
+			PTN5150_REG_CC_PORT_ATTACHMENT_MASK) >>
+			PTN5150_REG_CC_PORT_ATTACHMENT_SHIFT);
+
+	switch (port_status) {
+	case PTN5150_DFP_ATTACHED:
+		extcon_set_state_sync(info->edev, EXTCON_USB_HOST, false);
+		gpiod_set_value_cansleep(info->vbus_gpiod, 0);
+		extcon_set_state_sync(info->edev, EXTCON_USB, true);
+		break;
+	case PTN5150_UFP_ATTACHED:
+		extcon_set_state_sync(info->edev, EXTCON_USB, false);
+		vbus = ((reg_data & PTN5150_REG_CC_VBUS_DETECTION_MASK) >>
+			PTN5150_REG_CC_VBUS_DETECTION_SHIFT);
+		if (vbus)
+			gpiod_set_value_cansleep(info->vbus_gpiod, 0);
+		else
+			gpiod_set_value_cansleep(info->vbus_gpiod, 1);
+
+		extcon_set_state_sync(info->edev, EXTCON_USB_HOST, true);
+		break;
+	default:
+		dev_err(info->dev, "Unknown Port status : %x\n", port_status);
+		break;
+	}
+}
+
 static void ptn5150_irq_work(struct work_struct *work)
 {
 	struct ptn5150_info *info = container_of(work,
 			struct ptn5150_info, irq_work);
 	int ret = 0;
-	unsigned int reg_data;
 	unsigned int int_status;
 
 	if (!info->edev)
@@ -96,13 +134,6 @@ static void ptn5150_irq_work(struct work_struct *work)
 
 	mutex_lock(&info->mutex);
 
-	ret = regmap_read(info->regmap, PTN5150_REG_CC_STATUS, &reg_data);
-	if (ret) {
-		dev_err(info->dev, "failed to read CC STATUS %d\n", ret);
-		mutex_unlock(&info->mutex);
-		return;
-	}
-
 	/* Clear interrupt. Read would clear the register */
 	ret = regmap_read(info->regmap, PTN5150_REG_INT_STATUS, &int_status);
 	if (ret) {
@@ -116,41 +147,7 @@ static void ptn5150_irq_work(struct work_struct *work)
 
 		cable_attach = int_status & PTN5150_REG_INT_CABLE_ATTACH_MASK;
 		if (cable_attach) {
-			unsigned int port_status;
-			unsigned int vbus;
-
-			port_status = ((reg_data &
-					PTN5150_REG_CC_PORT_ATTACHMENT_MASK) >>
-					PTN5150_REG_CC_PORT_ATTACHMENT_SHIFT);
-
-			switch (port_status) {
-			case PTN5150_DFP_ATTACHED:
-				extcon_set_state_sync(info->edev,
-						EXTCON_USB_HOST, false);
-				gpiod_set_value_cansleep(info->vbus_gpiod, 0);
-				extcon_set_state_sync(info->edev, EXTCON_USB,
-						true);
-				break;
-			case PTN5150_UFP_ATTACHED:
-				extcon_set_state_sync(info->edev, EXTCON_USB,
-						false);
-				vbus = ((reg_data &
-					PTN5150_REG_CC_VBUS_DETECTION_MASK) >>
-					PTN5150_REG_CC_VBUS_DETECTION_SHIFT);
-				if (vbus)
-					gpiod_set_value_cansleep(info->vbus_gpiod, 0);
-				else
-					gpiod_set_value_cansleep(info->vbus_gpiod, 1);
-
-				extcon_set_state_sync(info->edev,
-						EXTCON_USB_HOST, true);
-				break;
-			default:
-				dev_err(info->dev,
-					"Unknown Port status : %x\n",
-					port_status);
-				break;
-			}
+			ptn5150_check_state(info);
 		} else {
 			extcon_set_state_sync(info->edev,
 					EXTCON_USB_HOST, false);
@@ -302,6 +299,14 @@ static int ptn5150_i2c_probe(struct i2c_client *i2c,
 	if (ret)
 		return -EINVAL;
 
+	/*
+	 * Update current extcon state if for example OTG connection was there
+	 * before the probe
+	 */
+	mutex_lock(&info->mutex);
+	ptn5150_check_state(info);
+	mutex_unlock(&info->mutex);
+
 	return 0;
 }
 
@@ -334,4 +339,5 @@ subsys_initcall(ptn5150_i2c_init);
 
 MODULE_DESCRIPTION("NXP PTN5150 CC logic Extcon driver");
 MODULE_AUTHOR("Vijai Kumar K <vijaikumar.kanagarajan@gmail.com>");
+MODULE_AUTHOR("Krzysztof Kozlowski <krzk@kernel.org>");
 MODULE_LICENSE("GPL v2");