iio: sx9500: add power management

Signed-off-by: Vlad Dogaru <vlad.dogaru@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/iio/proximity/sx9500.c b/drivers/iio/proximity/sx9500.c
index fa40f6d..d2c52f9 100644 (file)
--- a/drivers/iio/proximity/sx9500.c
+++ b/drivers/iio/proximity/sx9500.c
@@ -18,6 +18,7 @@
 #include <linux/acpi.h>
 #include <linux/gpio/consumer.h>
 #include <linux/regmap.h>
+#include <linux/pm.h>
 
 #include <linux/iio/iio.h>
 #include <linux/iio/buffer.h>
@@ -89,6 +90,8 @@ struct sx9500_data {
        bool event_enabled[SX9500_NUM_CHANNELS];
        bool trigger_enabled;
        u16 *buffer;
+       /* Remember enabled channels and sample rate during suspend. */
+       unsigned int suspend_ctrl0;
 };
 
 static const struct iio_event_spec sx9500_events[] = {
@@ -720,6 +723,49 @@ static int sx9500_remove(struct i2c_client *client)
        return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int sx9500_suspend(struct device *dev)
+{
+       struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+       struct sx9500_data *data = iio_priv(indio_dev);
+       int ret;
+
+       mutex_lock(&data->mutex);
+       ret = regmap_read(data->regmap, SX9500_REG_PROX_CTRL0,
+                         &data->suspend_ctrl0);
+       if (ret < 0)
+               goto out;
+
+       /*
+        * Scan period doesn't matter because when all the sensors are
+        * deactivated the device is in sleep mode.
+        */
+       ret = regmap_write(data->regmap, SX9500_REG_PROX_CTRL0, 0);
+
+out:
+       mutex_unlock(&data->mutex);
+       return ret;
+}
+
+static int sx9500_resume(struct device *dev)
+{
+       struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+       struct sx9500_data *data = iio_priv(indio_dev);
+       int ret;
+
+       mutex_lock(&data->mutex);
+       ret = regmap_write(data->regmap, SX9500_REG_PROX_CTRL0,
+                          data->suspend_ctrl0);
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static const struct dev_pm_ops sx9500_pm_ops = {
+       SET_SYSTEM_SLEEP_PM_OPS(sx9500_suspend, sx9500_resume)
+};
+
 static const struct acpi_device_id sx9500_acpi_match[] = {
        {"SSX9500", 0},
        { },
@@ -736,6 +782,7 @@ static struct i2c_driver sx9500_driver = {
        .driver = {
                .name   = SX9500_DRIVER_NAME,
                .acpi_match_table = ACPI_PTR(sx9500_acpi_match),
+               .pm = &sx9500_pm_ops,
        },
        .probe          = sx9500_probe,
        .remove         = sx9500_remove,