extcon: max77693: Fix bug of wrong pointer when platform data is not used

This patch fix wrong pointer of platform data. If each machine set
platform data for h/w path or delay time of workqueue, this driver
happen kernel panic related to null pointer.
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Myungjoo Ham <myungjoo.ham@samsung.com>

drivers/extcon/extcon-max77693.c

@@ -1045,7 +1045,6 @@ static int max77693_muic_probe(struct platform_device *pdev)
 {
 	struct max77693_dev *max77693 = dev_get_drvdata(pdev->dev.parent);
 	struct max77693_platform_data *pdata = dev_get_platdata(max77693->dev);
-	struct max77693_muic_platform_data *muic_pdata = pdata->muic_data;
 	struct max77693_muic_info *info;
 	int delay_jiffies;
 	int ret;
@@ -1145,44 +1144,63 @@ static int max77693_muic_probe(struct platform_device *pdev)
 		goto err_irq;
 	}
 
-	/* Initialize MUIC register by using platform data */
-	for (i = 0 ; i < muic_pdata->num_init_data ; i++) {
-		enum max77693_irq_source irq_src = MAX77693_IRQ_GROUP_NR;
-
-		max77693_write_reg(info->max77693->regmap_muic,
-				muic_pdata->init_data[i].addr,
-				muic_pdata->init_data[i].data);
-
-		switch (muic_pdata->init_data[i].addr) {
-		case MAX77693_MUIC_REG_INTMASK1:
-			irq_src = MUIC_INT1;
-			break;
-		case MAX77693_MUIC_REG_INTMASK2:
-			irq_src = MUIC_INT2;
-			break;
-		case MAX77693_MUIC_REG_INTMASK3:
-			irq_src = MUIC_INT3;
-			break;
+	if (pdata->muic_data) {
+		struct max77693_muic_platform_data *muic_pdata = pdata->muic_data;
+
+		/* Initialize MUIC register by using platform data */
+		for (i = 0 ; i < muic_pdata->num_init_data ; i++) {
+			enum max77693_irq_source irq_src
+					= MAX77693_IRQ_GROUP_NR;
+
+			max77693_write_reg(info->max77693->regmap_muic,
+					muic_pdata->init_data[i].addr,
+					muic_pdata->init_data[i].data);
+
+			switch (muic_pdata->init_data[i].addr) {
+			case MAX77693_MUIC_REG_INTMASK1:
+				irq_src = MUIC_INT1;
+				break;
+			case MAX77693_MUIC_REG_INTMASK2:
+				irq_src = MUIC_INT2;
+				break;
+			case MAX77693_MUIC_REG_INTMASK3:
+				irq_src = MUIC_INT3;
+				break;
+			}
+
+			if (irq_src < MAX77693_IRQ_GROUP_NR)
+				info->max77693->irq_masks_cur[irq_src]
+					= muic_pdata->init_data[i].data;
 		}
 
-		if (irq_src < MAX77693_IRQ_GROUP_NR)
-			info->max77693->irq_masks_cur[irq_src]
-				= muic_pdata->init_data[i].data;
-	}
+		/*
+		 * Default usb/uart path whether UART/USB or AUX_UART/AUX_USB
+		 * h/w path of COMP2/COMN1 on CONTROL1 register.
+		 */
+		if (muic_pdata->path_uart)
+			info->path_uart = muic_pdata->path_uart;
+		else
+			info->path_uart = CONTROL1_SW_UART;
 
-	/*
-	 * Default usb/uart path whether UART/USB or AUX_UART/AUX_USB
-	 * h/w path of COMP2/COMN1 on CONTROL1 register.
-	 */
-	if (muic_pdata->path_uart)
-		info->path_uart = muic_pdata->path_uart;
-	else
-		info->path_uart = CONTROL1_SW_UART;
+		if (muic_pdata->path_usb)
+			info->path_usb = muic_pdata->path_usb;
+		else
+			info->path_usb = CONTROL1_SW_USB;
 
-	if (muic_pdata->path_usb)
-		info->path_usb = muic_pdata->path_usb;
-	else
+		/*
+		 * Default delay time for detecting cable state
+		 * after certain time.
+		 */
+		if (muic_pdata->detcable_delay_ms)
+			delay_jiffies =
+				msecs_to_jiffies(muic_pdata->detcable_delay_ms);
+		else
+			delay_jiffies = msecs_to_jiffies(DELAY_MS_DEFAULT);
+	} else {
 		info->path_usb = CONTROL1_SW_USB;
+		info->path_uart = CONTROL1_SW_UART;
+		delay_jiffies = msecs_to_jiffies(DELAY_MS_DEFAULT);
+	}
 
 	/* Set initial path for UART */
 	 max77693_muic_set_path(info, info->path_uart, true);
@@ -1208,10 +1226,6 @@ static int max77693_muic_probe(struct platform_device *pdev)
 	 * driver should notify cable state to upper layer.
 	 */
 	INIT_DELAYED_WORK(&info->wq_detcable, max77693_muic_detect_cable_wq);
-	if (muic_pdata->detcable_delay_ms)
-		delay_jiffies = msecs_to_jiffies(muic_pdata->detcable_delay_ms);
-	else
-		delay_jiffies = msecs_to_jiffies(DELAY_MS_DEFAULT);
 	schedule_delayed_work(&info->wq_detcable, delay_jiffies);
 
 	return ret;