Commit 2bf9233a authored by Chris Verges's avatar Chris Verges Committed by Guenter Roeck
Browse files

hwmon: (lm73) Add support for max/min alarms 



Add support for temp1_min_alarm and temp1_max_alarm

Signed-off-by: default avatarChris Verges <kg4ysn@gmail.com>
[linux@roeck-us.net: cleanup; dropped platform data and interrupt support]
Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent 8c14d126

Documentation/hwmon/lm73

+11 −0
Original line number Diff line number Diff line
@@ -77,3 +77,14 @@ via the following function: 


where 'x' is the output from 'update_interval' and 'g(x)' is the

resolution in degrees C per LSB.



Alarm Support

-------------



The LM73 features a simple over-temperature alarm mechanism.  This

feature is exposed via the sysfs attributes.



The attributes 'temp1_max_alarm' and 'temp1_min_alarm' are flags

provided by the LM73 that indicate whether the measured temperature has

passed the 'temp1_max' and 'temp1_min' thresholds, respectively.  These

values _must_ be read to clear the registers on the LM73.

drivers/hwmon/lm73.c

+32 −0
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ 
 * Guillaume Ligneul <guillaume.ligneul@gmail.com>

 * Adrien Demarez <adrien.demarez@bolloretelecom.eu>

 * Jeremy Laine <jeremy.laine@bolloretelecom.eu>

 * Chris Verges <kg4ysn@gmail.com>

 *

 * This software program is licensed subject to the GNU General Public License

 * (GPL).Version 2,June 1991, available at
@@ -43,6 +44,9 @@ static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4c, 
#define LM73_CTRL_RES_MASK	(BIT(5) | BIT(6))

#define LM73_CTRL_TO_MASK	BIT(7)



#define LM73_CTRL_HI_SHIFT	2

#define LM73_CTRL_LO_SHIFT	1



static const unsigned short lm73_convrates[] = {

	14,	/* 11-bits (0.25000 C/LSB): RES1 Bit = 0, RES0 Bit = 0 */

	28,	/* 12-bits (0.12500 C/LSB): RES1 Bit = 0, RES0 Bit = 1 */
@@ -140,6 +144,28 @@ static ssize_t show_convrate(struct device *dev, struct device_attribute *da, 
	return scnprintf(buf, PAGE_SIZE, "%hu\n", lm73_convrates[res]);

}



static ssize_t show_maxmin_alarm(struct device *dev,

				 struct device_attribute *da, char *buf)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);

	struct lm73_data *data = i2c_get_clientdata(client);

	s32 ctrl;



	mutex_lock(&data->lock);

	ctrl = i2c_smbus_read_byte_data(client, LM73_REG_CTRL);

	if (ctrl < 0)

		goto abort;

	data->ctrl = ctrl;

	mutex_unlock(&data->lock);



	return scnprintf(buf, PAGE_SIZE, "%d\n", (ctrl >> attr->index) & 1);



abort:

	mutex_unlock(&data->lock);

	return ctrl;

}



/*-----------------------------------------------------------------------*/



/* sysfs attributes for hwmon */
@@ -152,12 +178,18 @@ static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, 
			show_temp, NULL, LM73_REG_INPUT);

static SENSOR_DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO,

			show_convrate, set_convrate, 0);

static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO,

			show_maxmin_alarm, NULL, LM73_CTRL_HI_SHIFT);

static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO,

			show_maxmin_alarm, NULL, LM73_CTRL_LO_SHIFT);



static struct attribute *lm73_attributes[] = {

	&sensor_dev_attr_temp1_input.dev_attr.attr,

	&sensor_dev_attr_temp1_max.dev_attr.attr,

	&sensor_dev_attr_temp1_min.dev_attr.attr,

	&sensor_dev_attr_update_interval.dev_attr.attr,

	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,

	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,

	NULL

};