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>

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>
Shubhrajyoti Datta · Jean Delvare
1 parent 960f12f4d1
Showing 2 changed files with 40 additions and 0 deletions Side-by-side Diff
drivers/hwmon/lm75.c
drivers/hwmon/lm75.h
@@ -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,
@@ -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 */
...	...	@@ -280,10 +280,49 @@
280	280	return 0;
281	281	}
282	282
	283	+#ifdef CONFIG_PM
	284	+static int lm75_suspend(struct device *dev)
	285	+{
	286	+ int status;
	287	+ struct i2c_client *client = to_i2c_client(dev);
	288	+ status = lm75_read_value(client, LM75_REG_CONF);
	289	+ if (status < 0) {
	290	+ dev_dbg(&client->dev, "Can't read config? %d\n", status);
	291	+ return status;
	292	+ }
	293	+ status = status \| LM75_SHUTDOWN;
	294	+ lm75_write_value(client, LM75_REG_CONF, status);
	295	+ return 0;
	296	+}
	297	+
	298	+static int lm75_resume(struct device *dev)
	299	+{
	300	+ int status;
	301	+ struct i2c_client *client = to_i2c_client(dev);
	302	+ status = lm75_read_value(client, LM75_REG_CONF);
	303	+ if (status < 0) {
	304	+ dev_dbg(&client->dev, "Can't read config? %d\n", status);
	305	+ return status;
	306	+ }
	307	+ status = status & ~LM75_SHUTDOWN;
	308	+ lm75_write_value(client, LM75_REG_CONF, status);
	309	+ return 0;
	310	+}
	311	+
	312	+static const struct dev_pm_ops lm75_dev_pm_ops = {
	313	+ .suspend = lm75_suspend,
	314	+ .resume = lm75_resume,
	315	+};
	316	+#define LM75_DEV_PM_OPS (&lm75_dev_pm_ops)
	317	+#else
	318	+#define LM75_DEV_PM_OPS NULL
	319	+#endif /* CONFIG_PM */
	320	+
283	321	static struct i2c_driver lm75_driver = {
284	322	.class = I2C_CLASS_HWMON,
285	323	.driver = {
286	324	.name = "lm75",
	325	+ .pm = LM75_DEV_PM_OPS,
287	326	},
288	327	.probe = lm75_probe,
289	328	.remove = lm75_remove,
...	...	@@ -30,6 +30,7 @@
30	30	/* straight from the datasheet */
31	31	#define LM75_TEMP_MIN (-55000)
32	32	#define LM75_TEMP_MAX 125000
	33	+#define LM75_SHUTDOWN 0x01
33	34
34	35	/* TEMP: 0.001C/bit (-55C to +125C)
35	36	REG: (0.5C/bit, two's complement) << 7 */