diff --git a/drivers/mfd/mc13xxx.c b/drivers/mfd/mc13xxx.c
index 466a11cb4..2be6f627a 100644
--- a/drivers/mfd/mc13xxx.c
+++ b/drivers/mfd/mc13xxx.c
@@ -28,19 +28,15 @@
 
 #define DRIVERNAME		"mc13xxx"
 
-enum mc13xxx_mode {
-	MC13XXX_MODE_I2C,
-	MC13XXX_MODE_SPI,
-};
-
 struct mc13xxx {
 	struct cdev			cdev;
 	union {
 		struct i2c_client	*client;
 		struct spi_device	*spi;
 	};
-	enum mc13xxx_mode		mode;
 	int				revision;
+	int				(*reg_read)(struct mc13xxx*, u8, u32*);
+	int				(*reg_write)(struct mc13xxx*, u8, u32);
 };
 
 #define to_mc13xxx(a)		container_of(a, struct mc13xxx, cdev)
@@ -136,29 +132,13 @@ static int mc13xxx_i2c_reg_write(struct mc13xxx *mc13xxx, u8 reg, u32 val)
 
 int mc13xxx_reg_write(struct mc13xxx *mc13xxx, u8 reg, u32 val)
 {
-#ifdef CONFIG_I2C
-	if (mc13xxx->mode == MC13XXX_MODE_I2C)
-		return mc13xxx_i2c_reg_write(mc13xxx, reg, val);
-#endif
-#ifdef CONFIG_SPI
-	if (mc13xxx->mode == MC13XXX_MODE_SPI)
-		return mc13xxx_spi_reg_write(mc13xxx, reg, val);
-#endif
-	return -EINVAL;
+	return mc13xxx->reg_write(mc13xxx, reg, val);
 }
 EXPORT_SYMBOL(mc13xxx_reg_write);
 
 int mc13xxx_reg_read(struct mc13xxx *mc13xxx, u8 reg, u32 *val)
 {
-#ifdef CONFIG_I2C
-	if (mc13xxx->mode == MC13XXX_MODE_I2C)
-		return mc13xxx_i2c_reg_read(mc13xxx, reg, val);
-#endif
-#ifdef CONFIG_SPI
-	if (mc13xxx->mode == MC13XXX_MODE_SPI)
-		return mc13xxx_spi_reg_read(mc13xxx, reg, val);
-#endif
-	return -EINVAL;
+	return mc13xxx->reg_read(mc13xxx, reg, val);
 }
 EXPORT_SYMBOL(mc13xxx_reg_read);
 
@@ -179,7 +159,7 @@ EXPORT_SYMBOL(mc13xxx_set_bits);
 
 static ssize_t mc_read(struct cdev *cdev, void *_buf, size_t count, loff_t offset, ulong flags)
 {
-	struct mc13xxx *priv = to_mc13xxx(cdev);
+	struct mc13xxx *mc13xxx = to_mc13xxx(cdev);
 	u32 *buf = _buf;
 	size_t i = count >> 2;
 	int err;
@@ -187,7 +167,7 @@ static ssize_t mc_read(struct cdev *cdev, void *_buf, size_t count, loff_t offse
 	offset >>= 2;
 
 	while (i) {
-		err = mc13xxx_reg_read(priv, offset, buf);
+		err = mc13xxx_reg_read(mc13xxx, offset, buf);
 		if (err)
 			return (ssize_t)err;
 		buf++;
@@ -297,7 +277,7 @@ static int mc13xxx_query_revision(struct mc13xxx *mc13xxx)
 	return rev;
 }
 
-static int mc_probe(struct device_d *dev, enum mc13xxx_mode mode)
+static int __init mc_probe(struct device_d *dev)
 {
 	int rev;
 
@@ -305,17 +285,26 @@ static int mc_probe(struct device_d *dev, enum mc13xxx_mode mode)
 		return -EBUSY;
 
 	mc_dev = xzalloc(sizeof(struct mc13xxx));
-	mc_dev->mode = mode;
 	mc_dev->cdev.name = DRIVERNAME;
-	if (mode == MC13XXX_MODE_I2C) {
+
+#ifdef CONFIG_I2C
+	if (dev->bus == &i2c_bus) {
 		mc_dev->client = to_i2c_client(dev);
+		mc_dev->reg_read = mc13xxx_i2c_reg_read;
+		mc_dev->reg_write = mc13xxx_i2c_reg_write;
 	}
-	if (mode == MC13XXX_MODE_SPI) {
+#endif
+#ifdef CONFIG_SPI
+	if (dev->bus == &spi_bus) {
 		mc_dev->spi = dev->type_data;
 		mc_dev->spi->mode = SPI_MODE_0 | SPI_CS_HIGH;
 		mc_dev->spi->bits_per_word = 32;
 		mc_dev->spi->max_speed_hz = 20000000;
+		mc_dev->reg_read = mc13xxx_spi_reg_read;
+		mc_dev->reg_write = mc13xxx_spi_reg_write;
 	}
+#endif
+
 	mc_dev->cdev.size = 256;
 	mc_dev->cdev.dev = dev;
 	mc_dev->cdev.ops = &mc_fops;
@@ -343,14 +332,9 @@ static __maybe_unused struct of_device_id mc13892_dt_ids[] = {
 };
 
 #ifdef CONFIG_I2C
-static int mc_i2c_probe(struct device_d *dev)
-{
-	return mc_probe(dev, MC13XXX_MODE_I2C);
-}
-
 static struct driver_d mc_i2c_driver = {
 	.name  = "mc13xxx-i2c",
-	.probe = mc_i2c_probe,
+	.probe	= mc_probe,
 	.of_compatible = DRV_OF_COMPAT(mc13892_dt_ids),
 };
 
@@ -362,14 +346,9 @@ device_initcall(mc_i2c_init);
 #endif
 
 #ifdef CONFIG_SPI
-static int mc_spi_probe(struct device_d *dev)
-{
-	return mc_probe(dev, MC13XXX_MODE_SPI);
-}
-
 static struct driver_d mc_spi_driver = {
 	.name  = "mc13xxx-spi",
-	.probe = mc_spi_probe,
+	.probe	= mc_probe,
 	.of_compatible = DRV_OF_COMPAT(mc13892_dt_ids),
 };
 device_spi_driver(mc_spi_driver);