From 2bf9233a108cea32edbb5a65afa8e609fa146577 Mon Sep 17 00:00:00 2001 From: Chris Verges Date: Sat, 5 Jan 2013 01:41:20 -0800 Subject: hwmon: (lm73) Add support for max/min alarms Add support for temp1_min_alarm and temp1_max_alarm Signed-off-by: Chris Verges [linux@roeck-us.net: cleanup; dropped platform data and interrupt support] Signed-off-by: Guenter Roeck --- Documentation/hwmon/lm73 | 11 +++++++++++ drivers/hwmon/lm73.c | 32 ++++++++++++++++++++++++++++++++ 2 files changed, 43 insertions(+) diff --git a/Documentation/hwmon/lm73 b/Documentation/hwmon/lm73 index 782b3e1..8af059d 100644 --- a/Documentation/hwmon/lm73 +++ b/Documentation/hwmon/lm73 @@ -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. diff --git a/drivers/hwmon/lm73.c b/drivers/hwmon/lm73.c index 0b19f03..9bde964 100644 --- a/drivers/hwmon/lm73.c +++ b/drivers/hwmon/lm73.c @@ -8,6 +8,7 @@ * Guillaume Ligneul * Adrien Demarez * Jeremy Laine + * Chris Verges * * 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 }; -- cgit v1.1