[PATCH v10 3/3] i2c: muxes: pca954x: Add regulator support

[Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>]

Add a vdd regulator and enable it for boards that have the
mux powered off by default.

Signed-off-by: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>
---
 drivers/i2c/muxes/i2c-mux-pca954x.c | 35 ++++++++++++++++++++++++-----
 1 file changed, 30 insertions(+), 5 deletions(-)

diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index 39f313658b18..0d966a55b727 100644
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -49,6 +49,7 @@
 #include <linux/module.h>
 #include <linux/pm.h>
 #include <linux/property.h>
+#include <linux/regulator/consumer.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <dt-bindings/mux/mux.h>
@@ -101,6 +102,7 @@ struct pca954x {
 	struct irq_domain *irq;
 	unsigned int irq_mask;
 	raw_spinlock_t lock;
+	struct regulator *supply;
 };
 
 /* Provide specs for the MAX735x, PCA954x and PCA984x types we know about */
@@ -440,6 +442,9 @@ static void pca954x_cleanup(struct i2c_mux_core *muxc)
 	struct pca954x *data = i2c_mux_priv(muxc);
 	int c, irq;
 
+	if (data->supply)
+		regulator_disable(data->supply);
+
 	if (data->irq) {
 		for (c = 0; c < data->chip->nchans; c++) {
 			irq = irq_find_mapping(data->irq, c);
@@ -492,10 +497,28 @@ static int pca954x_probe(struct i2c_client *client)
 	i2c_set_clientdata(client, muxc);
 	data->client = client;
 
+	data->supply = devm_regulator_get_optional(dev, "vdd");
+	if (IS_ERR(data->supply)) {
+		ret = PTR_ERR(data->supply);
+		if (ret != -ENODEV)
+			return dev_err_probe(dev, ret,
+				"Failed to request regulator\n");
+		else
+			data->supply = NULL;
+	} else {
+		ret = regulator_enable(data->supply);
+		if (ret) {
+			dev_err(dev, "Failed to enable regulator: %d\n", ret);
+			return ret;
+		}
+	}
+
 	/* Reset the mux if a reset GPIO is specified. */
 	gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
-	if (IS_ERR(gpio))
-		return PTR_ERR(gpio);
+	if (IS_ERR(gpio)) {
+		ret = PTR_ERR(gpio);
+		goto fail_cleanup;
+	}
 	if (gpio) {
 		udelay(1);
 		gpiod_set_value_cansleep(gpio, 0);
@@ -512,7 +535,7 @@ static int pca954x_probe(struct i2c_client *client)
 
 		ret = i2c_get_device_id(client, &id);
 		if (ret && ret != -EOPNOTSUPP)
-			return ret;
+			goto fail_cleanup;
 
 		if (!ret &&
 		    (id.manufacturer_id != data->chip->id.manufacturer_id ||
@@ -520,7 +543,8 @@ static int pca954x_probe(struct i2c_client *client)
 			dev_warn(dev, "unexpected device id %03x-%03x-%x\n",
 				 id.manufacturer_id, id.part_id,
 				 id.die_revision);
-			return -ENODEV;
+			ret = -ENODEV;
+			goto fail_cleanup;
 		}
 	}
 
@@ -539,7 +563,8 @@ static int pca954x_probe(struct i2c_client *client)
 	ret = pca954x_init(client, data);
 	if (ret < 0) {
 		dev_warn(dev, "probe failed\n");
-		return -ENODEV;
+		ret = -ENODEV;
+		goto fail_cleanup;
 	}
 
 	ret = pca954x_irq_setup(muxc);
-- 
2.39.1