rtc: rv3029: Add thermometer hwmon support
This adds support to
- enable/disable the thermometer
- set the temperature scanning interval
- read the current temperature that is used for temp compensation.
via hwmon interface
Signed-off-by: Michael Buesch <m@bues.ch>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
diff --git a/drivers/rtc/rtc-rv3029c2.c b/drivers/rtc/rtc-rv3029c2.c
index 3bbb581..d0cbf08 100644
--- a/drivers/rtc/rtc-rv3029c2.c
+++ b/drivers/rtc/rtc-rv3029c2.c
@@ -18,6 +18,8 @@
#include <linux/rtc.h>
#include <linux/delay.h>
#include <linux/of.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
/* Register map */
@@ -637,6 +639,123 @@
}
}
+#ifdef CONFIG_RTC_DRV_RV3029_HWMON
+
+static int rv3029_read_temp(struct i2c_client *client, int *temp_mC)
+{
+ int ret;
+ u8 temp;
+
+ ret = rv3029_i2c_read_regs(client, RV3029_TEMP_PAGE, &temp, 1);
+ if (ret < 0)
+ return ret;
+
+ *temp_mC = ((int)temp - 60) * 1000;
+
+ return 0;
+}
+
+static ssize_t rv3029_hwmon_show_temp(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct i2c_client *client = dev_get_drvdata(dev);
+ int ret, temp_mC;
+
+ ret = rv3029_read_temp(client, &temp_mC);
+ if (ret < 0)
+ return ret;
+
+ return sprintf(buf, "%d\n", temp_mC);
+}
+
+static ssize_t rv3029_hwmon_set_update_interval(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t count)
+{
+ struct i2c_client *client = dev_get_drvdata(dev);
+ unsigned long interval_ms;
+ int ret;
+ u8 th_set_bits = 0;
+
+ ret = kstrtoul(buf, 10, &interval_ms);
+ if (ret < 0)
+ return ret;
+
+ if (interval_ms != 0) {
+ th_set_bits |= RV3029_EECTRL_THE;
+ if (interval_ms >= 16000)
+ th_set_bits |= RV3029_EECTRL_THP;
+ }
+ ret = rv3029_eeprom_update_bits(client, RV3029_CONTROL_E2P_EECTRL,
+ RV3029_EECTRL_THE | RV3029_EECTRL_THP,
+ th_set_bits);
+ if (ret < 0)
+ return ret;
+
+ return count;
+}
+
+static ssize_t rv3029_hwmon_show_update_interval(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct i2c_client *client = dev_get_drvdata(dev);
+ int ret, interval_ms;
+ u8 eectrl;
+
+ ret = rv3029_eeprom_read(client, RV3029_CONTROL_E2P_EECTRL,
+ &eectrl, 1);
+ if (ret < 0)
+ return ret;
+
+ if (eectrl & RV3029_EECTRL_THE) {
+ if (eectrl & RV3029_EECTRL_THP)
+ interval_ms = 16000;
+ else
+ interval_ms = 1000;
+ } else {
+ interval_ms = 0;
+ }
+
+ return sprintf(buf, "%d\n", interval_ms);
+}
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, rv3029_hwmon_show_temp,
+ NULL, 0);
+static SENSOR_DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO,
+ rv3029_hwmon_show_update_interval,
+ rv3029_hwmon_set_update_interval, 0);
+
+static struct attribute *rv3029_hwmon_attrs[] = {
+ &sensor_dev_attr_temp1_input.dev_attr.attr,
+ &sensor_dev_attr_update_interval.dev_attr.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(rv3029_hwmon);
+
+static void rv3029_hwmon_register(struct i2c_client *client)
+{
+ struct device *hwmon_dev;
+
+ hwmon_dev = devm_hwmon_device_register_with_groups(
+ &client->dev, client->name, client, rv3029_hwmon_groups);
+ if (IS_ERR(hwmon_dev)) {
+ dev_warn(&client->dev,
+ "unable to register hwmon device %ld\n",
+ PTR_ERR(hwmon_dev));
+ }
+}
+
+#else /* CONFIG_RTC_DRV_RV3029_HWMON */
+
+static void rv3029_hwmon_register(struct i2c_client *client)
+{
+}
+
+#endif /* CONFIG_RTC_DRV_RV3029_HWMON */
+
static const struct rtc_class_ops rv3029_rtc_ops = {
.read_time = rv3029_rtc_read_time,
.set_time = rv3029_rtc_set_time,
@@ -668,6 +787,7 @@
}
rv3029_trickle_config(client);
+ rv3029_hwmon_register(client);
rtc = devm_rtc_device_register(&client->dev, client->name,
&rv3029_rtc_ops, THIS_MODULE);