[v3 3/3] i2c: muxes: pca954x: Add regulator support

From: Patrick Rudolph
Date: Thu Jan 20 2022 - 07:14:50 EST


Add an optional vdd regulator and enable it when found for devices
that are powered off by default.

Signed-off-by: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>
---
drivers/i2c/muxes/i2c-mux-pca954x.c | 32 ++++++++++++++++++++++++-----
1 file changed, 27 insertions(+), 5 deletions(-)

diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index 33b9a6a1fffa..086647193ea9 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>
@@ -119,6 +120,7 @@ struct pca954x {
struct irq_domain *irq;
unsigned int irq_mask;
raw_spinlock_t lock;
+ struct regulator *supply;
};

/* Provide specs for the PCA954x and MAX735x types we know about */
@@ -459,6 +461,9 @@ static void pca954x_cleanup(struct i2c_mux_core *muxc)
struct pca954x *data = i2c_mux_priv(muxc);
int c, irq;

+ if (!IS_ERR_OR_NULL(data->supply))
+ regulator_disable(data->supply);
+
if (data->irq) {
for (c = 0; c < data->chip->nchans; c++) {
irq = irq_find_mapping(data->irq, c);
@@ -513,15 +518,30 @@ static int pca954x_probe(struct i2c_client *client,
pca954x_select_chan, pca954x_deselect_mux);
if (!muxc)
return -ENOMEM;
+
data = i2c_mux_priv(muxc);

i2c_set_clientdata(client, muxc);
data->client = client;

+ data->supply = devm_regulator_get_optional(dev, "vdd");
+ if (IS_ERR(data->supply)) {
+ if ((PTR_ERR(data->supply) == -EPROBE_DEFER))
+ return -EPROBE_DEFER;
+ } else {
+ ret = regulator_enable(data->supply);
+ if (ret) {
+ dev_err(dev, "Failed to enable regulator vdd: %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);
@@ -538,7 +558,7 @@ 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 ||
@@ -546,7 +566,8 @@ 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;
}
}

@@ -565,7 +586,8 @@ 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);
--
2.34.1