From b54e976e77462f9a1a2cd0018cb5e3d15670aa85 Mon Sep 17 00:00:00 2001
From: Alistair Francis <alistair@alistair23.me>
Date: Wed, 20 Jan 2021 22:28:31 -0800
Subject: [PATCH] Input: wacom_i2c - Add support for vdd regulator

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

Signed-off-by: Alistair Francis <alistair@alistair23.me>
---
 drivers/input/touchscreen/wacom_i2c.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/drivers/input/touchscreen/wacom_i2c.c b/drivers/input/touchscreen/wacom_i2c.c
index 884c3e085e10..db792783902c 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;
@@ -221,6 +223,20 @@ static int wacom_i2c_probe(struct i2c_client *client,
 		goto err_free_mem;
 	}
 
+	wac_i2c->vdd = regulator_get(&client->dev, "vdd");
+	if (IS_ERR(wac_i2c->vdd)) {
+		error = PTR_ERR(wac_i2c->vdd);
+		kfree(wac_i2c);
+		return error;
+	}
+
+	error = regulator_enable(wac_i2c->vdd);
+	if (error) {
+		regulator_put(wac_i2c->vdd);
+		kfree(wac_i2c);
+		return error;
+	}
+
 	wac_i2c->client = client;
 	wac_i2c->input = input;
 
@@ -277,6 +293,8 @@ static int wacom_i2c_probe(struct i2c_client *client,
 err_free_irq:
 	free_irq(client->irq, wac_i2c);
 err_free_mem:
+	regulator_disable(wac_i2c->vdd);
+	regulator_put(wac_i2c->vdd);
 	input_free_device(input);
 	kfree(wac_i2c);