[PATCH 04/19] staging: iio: isl29028: add power management support

From: Brian Masney
Date: Sat Dec 03 2016 - 21:24:22 EST


This patch adds power management support to the isl29028 driver.

Signed-off-by: Brian Masney <masneyb@xxxxxxxxxxxxx>
---
drivers/staging/iio/light/isl29028.c | 59 ++++++++++++++++++++++++++++++++++++
1 file changed, 59 insertions(+)

diff --git a/drivers/staging/iio/light/isl29028.c b/drivers/staging/iio/light/isl29028.c
index 4f819a8..e96a8cb 100644
--- a/drivers/staging/iio/light/isl29028.c
+++ b/drivers/staging/iio/light/isl29028.c
@@ -75,6 +75,7 @@ struct isl29028_chip {

int lux_scale;
enum isl29028_als_ir_mode als_ir_mode;
+ bool suspended;
};

static int isl29028_set_proxim_sampling(struct isl29028_chip *chip,
@@ -274,6 +275,12 @@ static int isl29028_write_raw(struct iio_dev *indio_dev,
int ret = -EINVAL;

mutex_lock(&chip->lock);
+
+ if (chip->suspended) {
+ ret = -EBUSY;
+ goto write_done;
+ }
+
switch (chan->type) {
case IIO_PROXIMITY:
if (mask != IIO_CHAN_INFO_SAMP_FREQ) {
@@ -322,6 +329,8 @@ static int isl29028_write_raw(struct iio_dev *indio_dev,
dev_err(dev, "Unsupported channel type\n");
break;
}
+
+write_done:
mutex_unlock(&chip->lock);
return ret;
}
@@ -335,6 +344,12 @@ static int isl29028_read_raw(struct iio_dev *indio_dev,
int ret = -EINVAL;

mutex_lock(&chip->lock);
+
+ if (chip->suspended) {
+ ret = -EBUSY;
+ goto read_done;
+ }
+
switch (mask) {
case IIO_CHAN_INFO_RAW:
case IIO_CHAN_INFO_PROCESSED:
@@ -374,6 +389,8 @@ static int isl29028_read_raw(struct iio_dev *indio_dev,
dev_err(dev, "mask value 0x%08lx not supported\n", mask);
break;
}
+
+read_done:
mutex_unlock(&chip->lock);
return ret;
}
@@ -437,6 +454,9 @@ static int isl29028_chip_init_and_power_on(struct isl29028_chip *chip)
ret = isl29028_set_als_scale(chip, chip->lux_scale);
if (ret < 0)
dev_err(dev, "setting als scale failed, err = %d\n", ret);
+
+ chip->suspended = false;
+
return ret;
}

@@ -479,6 +499,7 @@ static int isl29028_probe(struct i2c_client *client,

i2c_set_clientdata(client, indio_dev);
mutex_init(&chip->lock);
+ chip->suspended = true;

chip->regmap = devm_regmap_init_i2c(client, &isl29028_regmap_config);
if (IS_ERR(chip->regmap)) {
@@ -530,6 +551,43 @@ static int isl29028_probe(struct i2c_client *client,
return 0;
}

+static int __maybe_unused isl29028_suspend(struct device *dev)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct isl29028_chip *chip = iio_priv(indio_dev);
+ int ret;
+
+ mutex_lock(&chip->lock);
+
+ ret = regmap_write(chip->regmap, ISL29028_REG_CONFIGURE, 0x0);
+ if (ret < 0)
+ dev_err(dev, "%s(): Error %d turning off chip\n", __func__,
+ ret);
+
+ chip->suspended = true;
+
+ mutex_unlock(&chip->lock);
+
+ return ret;
+}
+
+static int __maybe_unused isl29028_resume(struct device *dev)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct isl29028_chip *chip = iio_priv(indio_dev);
+ int ret;
+
+ mutex_lock(&chip->lock);
+
+ ret = isl29028_chip_init_and_power_on(chip);
+
+ mutex_unlock(&chip->lock);
+
+ return ret;
+}
+
+static SIMPLE_DEV_PM_OPS(isl29028_pm_ops, isl29028_suspend, isl29028_resume);
+
static const struct i2c_device_id isl29028_id[] = {
{"isl29028", 0},
{}
@@ -546,6 +604,7 @@ MODULE_DEVICE_TABLE(of, isl29028_of_match);
static struct i2c_driver isl29028_driver = {
.driver = {
.name = "isl29028",
+ .pm = &isl29028_pm_ops,
.of_match_table = isl29028_of_match,
},
.probe = isl29028_probe,
--
2.7.4