[PATCH v10 08/12] Input: wacom_i2c - Add support for vdd regulator

[Alistair Francis <alistair@xxxxxxxxxxxxx>]

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

Signed-off-by: Alistair Francis <alistair@xxxxxxxxxxxxx>
---
 drivers/input/touchscreen/wacom_i2c.c | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/drivers/input/touchscreen/wacom_i2c.c b/drivers/input/touchscreen/wacom_i2c.c
index a35d8fda7e7b..13341e76368b 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>
@@ -92,6 +93,7 @@ struct wacom_i2c {
 	struct input_dev *input;
 	struct touchscreen_properties props;
 	struct wacom_features features;
+	struct regulator *vdd;
 	u8 data[WACOM_QUERY_SIZE];
 	bool prox;
 	int tool;
@@ -278,6 +280,16 @@ static int wacom_i2c_probe(struct i2c_client *client,
 	if (!wac_i2c)
 		return -ENOMEM;
 
+	wac_i2c->vdd = regulator_get(&client->dev, "vdd");
+	if (IS_ERR(wac_i2c->vdd))
+		return PTR_ERR(wac_i2c->vdd);
+
+	error = regulator_enable(wac_i2c->vdd);
+	if (error) {
+		regulator_put(wac_i2c->vdd);
+		return error;
+	}
+
 	features = &wac_i2c->features;
 	error = wacom_query_device(client, features);
 	if (error)
@@ -286,8 +298,11 @@ static int wacom_i2c_probe(struct i2c_client *client,
 	wac_i2c->client = client;
 
 	input = devm_input_allocate_device(dev);
-	if (!input)
+	if (!input) {
+		regulator_disable(wac_i2c->vdd);
+		regulator_put(wac_i2c->vdd);
 		return -ENOMEM;
+	}
 
 	wac_i2c->input = input;
 
@@ -322,6 +337,8 @@ static int wacom_i2c_probe(struct i2c_client *client,
 					  IRQF_ONESHOT, "wacom_i2c", wac_i2c);
 	if (error) {
 		dev_err(dev, "Failed to request IRQ: %d\n", error);
+		regulator_disable(wac_i2c->vdd);
+		regulator_put(wac_i2c->vdd);
 		return error;
 	}
 
@@ -331,6 +348,8 @@ static int wacom_i2c_probe(struct i2c_client *client,
 	error = input_register_device(wac_i2c->input);
 	if (error) {
 		dev_err(dev, "Failed to register input device: %d\n", error);
+		regulator_disable(wac_i2c->vdd);
+		regulator_put(wac_i2c->vdd);
 		return error;
 	}
 
-- 
2.31.1