Add support for a VDD regulator. This allows the kernel to prove the
Wacom-I2C device on the rM2.

Signed-off-by: Alistair Francis <redacted>
---
 drivers/input/touchscreen/wacom_i2c.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/drivers/input/touchscreen/wacom_i2c.c b/drivers/input/touchscreen/wacom_i2c.c
index 7aa0d1c3dbc9..00db516fa3de 100644
--- a/drivers/input/touchscreen/wacom_i2c.c
+++ b/drivers/input/touchscreen/wacom_i2c.c

@@ -13,6 +13,7 @@
 #include <linux/irq.h>
 #include <linux/input/touchscreen.h>
 #include <linux/interrupt.h>
+#include <linux/regulator/consumer.h>
 #include <linux/reset.h>
 #include <linux/of.h>
 #include <asm/unaligned.h>

@@ -56,6 +57,7 @@ struct wacom_i2c {
 	struct i2c_client *client;
 	struct input_dev *input;
 	struct touchscreen_properties props;
+	struct regulator *vdd;
 	u8 data[WACOM_QUERY_SIZE];
 	bool prox;
 	int tool;

@@ -203,11 +205,29 @@ static int wacom_i2c_probe(struct i2c_client *client,
 	struct wacom_features features = { 0 };
 	int error;
 
+	wac_i2c = kzalloc(sizeof(*wac_i2c), GFP_KERNEL);
+	if (!wac_i2c)
+		return -ENOMEM;
+
 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 		dev_err(&client->dev, "i2c_check_functionality error\n");
 		return -EIO;