This patch adds to lm75 temperature sensor the possibility
to expose itself as thermal zone device, registered on the
thermal framework.
The thermal zone is built only if a device tree node
describing a thermal zone for this sensor is present
inside the lm75 DT node. Otherwise, the driver behavior
will be the same.
Cc: Jean Delvare <khali@xxxxxxxxxxxx>
Cc: Guenter Roeck <linux@xxxxxxxxxxxx>
Cc: lm-sensors@xxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Eduardo Valentin <eduardo.valentin@xxxxxx>
---
drivers/hwmon/lm75.c | 31 +++++++++++++++++++++++++++++++
1 file changed, 31 insertions(+)
diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
index c03b490..dc55908 100644
--- a/drivers/hwmon/lm75.c
+++ b/drivers/hwmon/lm75.c
@@ -27,6 +27,8 @@
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
+#include <linux/thermal.h>
+#include <linux/of.h>
#include "lm75.h"
@@ -70,6 +72,7 @@ static const u8 LM75_REG_TEMP[3] = {
/* Each client has this additional data */
struct lm75_data {
struct device *hwmon_dev;
+ struct thermal_zone_device *tz;
struct mutex update_lock;
u8 orig_conf;
u8 resolution; /* In bits, between 9 and 12 */
@@ -92,6 +95,19 @@ static struct lm75_data *lm75_update_device(struct device *dev);
/* sysfs attributes for hwmon */
+static int lm75_read_temp(void *dev, unsigned long *temp)
+{
+ struct lm75_data *data = lm75_update_device(dev);
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ *temp = ((data->temp[0] >> (16 - data->resolution)) * 1000) >>
+ (data->resolution - 8);
+
+ return 0;
+}
+
static ssize_t show_temp(struct device *dev, struct device_attribute *da,
char *buf)
{
@@ -271,11 +287,25 @@ lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
goto exit_remove;
}
+ if (of_find_property(client->dev.of_node, "monitored-zones", NULL)) {
+ data->tz = thermal_zone_of_device_register(&client->dev,
+ 0,
+ false, /* -hwmon */
+ &client->dev,
+ lm75_read_temp);
+ if (IS_ERR(data->tz)) {
+ status = PTR_ERR(data->tz);
+ goto exit_hwmon;
+ }
+ }
+
dev_info(&client->dev, "%s: sensor '%s'\n",
dev_name(data->hwmon_dev), client->name);
return 0;
+exit_hwmon:
+ hwmon_device_unregister(data->hwmon_dev);
exit_remove:
sysfs_remove_group(&client->dev.kobj, &lm75_group);
return status;
@@ -285,6 +315,7 @@ static int lm75_remove(struct i2c_client *client)
{
struct lm75_data *data = i2c_get_clientdata(client);
+ thermal_zone_device_unregister(data->tz);
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &lm75_group);
lm75_write_value(client, LM75_REG_CONF, data->orig_conf);
--
1.8.2.1.342.gfa7285d
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
