lan78xx: Add to handle mux control per chip id

Depends on chip, some EEPROM pins are muxed with LED function.
Disable & restore LED function to access EEPROM.

Signed-off-by: Woojung Huh <woojung.huh@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index 027ee37..650e716 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -462,32 +462,53 @@
 				   u32 length, u8 *data)
 {
 	u32 val;
+	u32 saved;
 	int i, ret;
+	int retval;
 
-	ret = lan78xx_eeprom_confirm_not_busy(dev);
-	if (ret)
-		return ret;
+	/* depends on chip, some EEPROM pins are muxed with LED function.
+	 * disable & restore LED function to access EEPROM.
+	 */
+	ret = lan78xx_read_reg(dev, HW_CFG, &val);
+	saved = val;
+	if ((dev->devid & ID_REV_CHIP_ID_MASK_) == 0x78000000) {
+		val &= ~(HW_CFG_LED1_EN_ | HW_CFG_LED0_EN_);
+		ret = lan78xx_write_reg(dev, HW_CFG, val);
+	}
+
+	retval = lan78xx_eeprom_confirm_not_busy(dev);
+	if (retval)
+		return retval;
 
 	for (i = 0; i < length; i++) {
 		val = E2P_CMD_EPC_BUSY_ | E2P_CMD_EPC_CMD_READ_;
 		val |= (offset & E2P_CMD_EPC_ADDR_MASK_);
 		ret = lan78xx_write_reg(dev, E2P_CMD, val);
-		if (unlikely(ret < 0))
-			return -EIO;
+		if (unlikely(ret < 0)) {
+			retval = -EIO;
+			goto exit;
+		}
 
-		ret = lan78xx_wait_eeprom(dev);
-		if (ret < 0)
-			return ret;
+		retval = lan78xx_wait_eeprom(dev);
+		if (retval < 0)
+			goto exit;
 
 		ret = lan78xx_read_reg(dev, E2P_DATA, &val);
-		if (unlikely(ret < 0))
-			return -EIO;
+		if (unlikely(ret < 0)) {
+			retval = -EIO;
+			goto exit;
+		}
 
 		data[i] = val & 0xFF;
 		offset++;
 	}
 
-	return 0;
+	retval = 0;
+exit:
+	if ((dev->devid & ID_REV_CHIP_ID_MASK_) == 0x78000000)
+		ret = lan78xx_write_reg(dev, HW_CFG, saved);
+
+	return retval;
 }
 
 static int lan78xx_read_eeprom(struct lan78xx_net *dev, u32 offset,
@@ -509,44 +530,67 @@
 				    u32 length, u8 *data)
 {
 	u32 val;
+	u32 saved;
 	int i, ret;
+	int retval;
 
-	ret = lan78xx_eeprom_confirm_not_busy(dev);
-	if (ret)
-		return ret;
+	/* depends on chip, some EEPROM pins are muxed with LED function.
+	 * disable & restore LED function to access EEPROM.
+	 */
+	ret = lan78xx_read_reg(dev, HW_CFG, &val);
+	saved = val;
+	if ((dev->devid & ID_REV_CHIP_ID_MASK_) == 0x78000000) {
+		val &= ~(HW_CFG_LED1_EN_ | HW_CFG_LED0_EN_);
+		ret = lan78xx_write_reg(dev, HW_CFG, val);
+	}
+
+	retval = lan78xx_eeprom_confirm_not_busy(dev);
+	if (retval)
+		goto exit;
 
 	/* Issue write/erase enable command */
 	val = E2P_CMD_EPC_BUSY_ | E2P_CMD_EPC_CMD_EWEN_;
 	ret = lan78xx_write_reg(dev, E2P_CMD, val);
-	if (unlikely(ret < 0))
-		return -EIO;
+	if (unlikely(ret < 0)) {
+		retval = -EIO;
+		goto exit;
+	}
 
-	ret = lan78xx_wait_eeprom(dev);
-	if (ret < 0)
-		return ret;
+	retval = lan78xx_wait_eeprom(dev);
+	if (retval < 0)
+		goto exit;
 
 	for (i = 0; i < length; i++) {
 		/* Fill data register */
 		val = data[i];
 		ret = lan78xx_write_reg(dev, E2P_DATA, val);
-		if (ret < 0)
-			return ret;
+		if (ret < 0) {
+			retval = -EIO;
+			goto exit;
+		}
 
 		/* Send "write" command */
 		val = E2P_CMD_EPC_BUSY_ | E2P_CMD_EPC_CMD_WRITE_;
 		val |= (offset & E2P_CMD_EPC_ADDR_MASK_);
 		ret = lan78xx_write_reg(dev, E2P_CMD, val);
-		if (ret < 0)
-			return ret;
+		if (ret < 0) {
+			retval = -EIO;
+			goto exit;
+		}
 
-		ret = lan78xx_wait_eeprom(dev);
-		if (ret < 0)
-			return ret;
+		retval = lan78xx_wait_eeprom(dev);
+		if (retval < 0)
+			goto exit;
 
 		offset++;
 	}
 
-	return 0;
+	retval = 0;
+exit:
+	if ((dev->devid & ID_REV_CHIP_ID_MASK_) == 0x78000000)
+		ret = lan78xx_write_reg(dev, HW_CFG, saved);
+
+	return retval;
 }
 
 static int lan78xx_read_raw_otp(struct lan78xx_net *dev, u32 offset,