hwmon: (lm75) Add suspend/resume feature
There is a shutdown feature at suspend it can be enabled to
reduce current consumption and resume it can be switched off.
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti@ti.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
index 393f354..ab5b87a 100644
--- a/drivers/hwmon/lm75.c
+++ b/drivers/hwmon/lm75.c
@@ -280,10 +280,49 @@
return 0;
}
+#ifdef CONFIG_PM
+static int lm75_suspend(struct device *dev)
+{
+ int status;
+ struct i2c_client *client = to_i2c_client(dev);
+ status = lm75_read_value(client, LM75_REG_CONF);
+ if (status < 0) {
+ dev_dbg(&client->dev, "Can't read config? %d\n", status);
+ return status;
+ }
+ status = status | LM75_SHUTDOWN;
+ lm75_write_value(client, LM75_REG_CONF, status);
+ return 0;
+}
+
+static int lm75_resume(struct device *dev)
+{
+ int status;
+ struct i2c_client *client = to_i2c_client(dev);
+ status = lm75_read_value(client, LM75_REG_CONF);
+ if (status < 0) {
+ dev_dbg(&client->dev, "Can't read config? %d\n", status);
+ return status;
+ }
+ status = status & ~LM75_SHUTDOWN;
+ lm75_write_value(client, LM75_REG_CONF, status);
+ return 0;
+}
+
+static const struct dev_pm_ops lm75_dev_pm_ops = {
+ .suspend = lm75_suspend,
+ .resume = lm75_resume,
+};
+#define LM75_DEV_PM_OPS (&lm75_dev_pm_ops)
+#else
+#define LM75_DEV_PM_OPS NULL
+#endif /* CONFIG_PM */
+
static struct i2c_driver lm75_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "lm75",
+ .pm = LM75_DEV_PM_OPS,
},
.probe = lm75_probe,
.remove = lm75_remove,
diff --git a/drivers/hwmon/lm75.h b/drivers/hwmon/lm75.h
index 7c93454..e547a3e 100644
--- a/drivers/hwmon/lm75.h
+++ b/drivers/hwmon/lm75.h
@@ -30,6 +30,7 @@
/* straight from the datasheet */
#define LM75_TEMP_MIN (-55000)
#define LM75_TEMP_MAX 125000
+#define LM75_SHUTDOWN 0x01
/* TEMP: 0.001C/bit (-55C to +125C)
REG: (0.5C/bit, two's complement) << 7 */