[PATCH v3 6/7] iio: light: al3320a implement suspend support

David Heidelberg
2020-02-01T18:01:36Z

AL3320a is fairly simple chip, so for suspend is enough to disable and
later enable it again.

Signed-off-by: David Heidelberg <david@ixit.cz>
---
drivers/iio/light/al3320a.c | 31 ++++++++++++++++++++++++++-----
1 file changed, 26 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/light/al3320a.c b/drivers/iio/light/al3320a.c
index 613830b7df6e..d99f9d139b5f 100644
--- a/drivers/iio/light/al3320a.c
+++ b/drivers/iio/light/al3320a.c
@@ -7,6 +7,9 @@
* IIO driver for AL3320A (7-bit I2C slave address 0x1C).
*
* TODO: interrupt support, thresholds
+ * When the driver will get support for interrupt handling, then interrupt
+ * will need to be disabled before turning sensor OFF in order to avoid
+ * potential races with the interrupt handling.
*/

#include <linux/module.h>
@@ -84,13 +87,19 @@ static const struct attribute_group al3320a_attribute_group = {
.attrs = al3320a_attributes,
};

+static int al3320a_set_pwr(struct i2c_client *client, bool pwr)
+{
+ u8 val = pwr ? AL3320A_CONFIG_ENABLE : AL3320A_CONFIG_DISABLE;
+ return i2c_smbus_write_byte_data(data->client, AL3320A_REG_CONFIG, val);
+}
+
+
static int al3320a_init(struct al3320a_data *data)
{
int ret;

- /* power on */
- ret = i2c_smbus_write_byte_data(data->client, AL3320A_REG_CONFIG,
- AL3320A_CONFIG_ENABLE);
+ ret = al3320a_set_pwr(data->client, true);
+
if (ret < 0)
return ret;

@@ -208,10 +217,21 @@ static int al3320a_probe(struct i2c_client *client,

static int al3320a_remove(struct i2c_client *client)
{
- return i2c_smbus_write_byte_data(client, AL3320A_REG_CONFIG,
- AL3320A_CONFIG_DISABLE);
+ return al3320a_set_pwr(client, false);
+}
+
+static int __maybe_unused al3320a_suspend(struct device *dev)
+{
+ return al3320a_set_pwr(to_i2c_client(dev), false);
+}
+
+static int __maybe_unused al3320a_resume(struct device *dev)
+{
+ return al3320a_set_pwr(to_i2c_client(dev), true);
}

+SIMPLE_DEV_PM_OPS(al3320a_pm_ops, al3320a_suspend, al3320a_resume);
+
static const struct i2c_device_id al3320a_id[] = {
{"al3320a", 0},
{}
@@ -221,6 +241,7 @@ MODULE_DEVICE_TABLE(i2c, al3320a_id);
static struct i2c_driver al3320a_driver = {
.driver = {
.name = AL3320A_DRV_NAME,
+ .pm = &al3320a_pm_ops,
},
.probe = al3320a_probe,
.remove = al3320a_remove,
--
2.25.0