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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/hwmon/lm73.c
Initial import
Diffstat (limited to 'drivers/hwmon/lm73.c')
-rw-r--r--drivers/hwmon/lm73.c287
1 files changed, 287 insertions, 0 deletions
diff --git a/drivers/hwmon/lm73.c b/drivers/hwmon/lm73.c
new file mode 100644
index 000000000..9653bb870
--- /dev/null
+++ b/drivers/hwmon/lm73.c
@@ -0,0 +1,287 @@
+/*
+ * LM73 Sensor driver
+ * Based on LM75
+ *
+ * Copyright (C) 2007, CenoSYS (www.cenosys.com).
+ * Copyright (C) 2009, Bollore telecom (www.bolloretelecom.eu).
+ *
+ * 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
+ * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/err.h>
+
+
+/* Addresses scanned */
+static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4c,
+ 0x4d, 0x4e, I2C_CLIENT_END };
+
+/* LM73 registers */
+#define LM73_REG_INPUT 0x00
+#define LM73_REG_CONF 0x01
+#define LM73_REG_MAX 0x02
+#define LM73_REG_MIN 0x03
+#define LM73_REG_CTRL 0x04
+#define LM73_REG_ID 0x07
+
+#define LM73_ID 0x9001 /* 0x0190, byte-swapped */
+#define DRVNAME "lm73"
+#define LM73_TEMP_MIN (-256000 / 250)
+#define LM73_TEMP_MAX (255750 / 250)
+
+#define LM73_CTRL_RES_SHIFT 5
+#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 */
+ 56, /* 13-bits (0.06250 C/LSB): RES1 Bit = 1, RES0 Bit = 0 */
+ 112, /* 14-bits (0.03125 C/LSB): RES1 Bit = 1, RES0 Bit = 1 */
+};
+
+struct lm73_data {
+ struct i2c_client *client;
+ struct mutex lock;
+ u8 ctrl; /* control register value */
+};
+
+/*-----------------------------------------------------------------------*/
+
+static ssize_t set_temp(struct device *dev, struct device_attribute *da,
+ const char *buf, size_t count)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ struct lm73_data *data = dev_get_drvdata(dev);
+ long temp;
+ short value;
+ s32 err;
+
+ int status = kstrtol(buf, 10, &temp);
+ if (status < 0)
+ return status;
+
+ /* Write value */
+ value = clamp_val(temp / 250, LM73_TEMP_MIN, LM73_TEMP_MAX) << 5;
+ err = i2c_smbus_write_word_swapped(data->client, attr->index, value);
+ return (err < 0) ? err : count;
+}
+
+static ssize_t show_temp(struct device *dev, struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ struct lm73_data *data = dev_get_drvdata(dev);
+ int temp;
+
+ s32 err = i2c_smbus_read_word_swapped(data->client, attr->index);
+ if (err < 0)
+ return err;
+
+ /* use integer division instead of equivalent right shift to
+ guarantee arithmetic shift and preserve the sign */
+ temp = (((s16) err) * 250) / 32;
+ return scnprintf(buf, PAGE_SIZE, "%d\n", temp);
+}
+
+static ssize_t set_convrate(struct device *dev, struct device_attribute *da,
+ const char *buf, size_t count)
+{
+ struct lm73_data *data = dev_get_drvdata(dev);
+ unsigned long convrate;
+ s32 err;
+ int res = 0;
+
+ err = kstrtoul(buf, 10, &convrate);
+ if (err < 0)
+ return err;
+
+ /*
+ * Convert the desired conversion rate into register bits.
+ * res is already initialized, and everything past the second-to-last
+ * value in the array is treated as belonging to the last value
+ * in the array.
+ */
+ while (res < (ARRAY_SIZE(lm73_convrates) - 1) &&
+ convrate > lm73_convrates[res])
+ res++;
+
+ mutex_lock(&data->lock);
+ data->ctrl &= LM73_CTRL_TO_MASK;
+ data->ctrl |= res << LM73_CTRL_RES_SHIFT;
+ err = i2c_smbus_write_byte_data(data->client, LM73_REG_CTRL,
+ data->ctrl);
+ mutex_unlock(&data->lock);
+
+ if (err < 0)
+ return err;
+
+ return count;
+}
+
+static ssize_t show_convrate(struct device *dev, struct device_attribute *da,
+ char *buf)
+{
+ struct lm73_data *data = dev_get_drvdata(dev);
+ int res;
+
+ res = (data->ctrl & LM73_CTRL_RES_MASK) >> LM73_CTRL_RES_SHIFT;
+ 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 sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ struct lm73_data *data = dev_get_drvdata(dev);
+ s32 ctrl;
+
+ mutex_lock(&data->lock);
+ ctrl = i2c_smbus_read_byte_data(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 */
+
+static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
+ show_temp, set_temp, LM73_REG_MAX);
+static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO,
+ show_temp, set_temp, LM73_REG_MIN);
+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_attrs[] = {
+ &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
+};
+ATTRIBUTE_GROUPS(lm73);
+
+/*-----------------------------------------------------------------------*/
+
+/* device probe and removal */
+
+static int
+lm73_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+ struct device *dev = &client->dev;
+ struct device *hwmon_dev;
+ struct lm73_data *data;
+ int ctrl;
+
+ data = devm_kzalloc(dev, sizeof(struct lm73_data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->client = client;
+ mutex_init(&data->lock);
+
+ ctrl = i2c_smbus_read_byte_data(client, LM73_REG_CTRL);
+ if (ctrl < 0)
+ return ctrl;
+ data->ctrl = ctrl;
+
+ hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
+ data, lm73_groups);
+ if (IS_ERR(hwmon_dev))
+ return PTR_ERR(hwmon_dev);
+
+ dev_info(dev, "sensor '%s'\n", client->name);
+
+ return 0;
+}
+
+static const struct i2c_device_id lm73_ids[] = {
+ { "lm73", 0 },
+ { /* LIST END */ }
+};
+MODULE_DEVICE_TABLE(i2c, lm73_ids);
+
+/* Return 0 if detection is successful, -ENODEV otherwise */
+static int lm73_detect(struct i2c_client *new_client,
+ struct i2c_board_info *info)
+{
+ struct i2c_adapter *adapter = new_client->adapter;
+ int id, ctrl, conf;
+
+ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
+ I2C_FUNC_SMBUS_WORD_DATA))
+ return -ENODEV;
+
+ /*
+ * Do as much detection as possible with byte reads first, as word
+ * reads can confuse other devices.
+ */
+ ctrl = i2c_smbus_read_byte_data(new_client, LM73_REG_CTRL);
+ if (ctrl < 0 || (ctrl & 0x10))
+ return -ENODEV;
+
+ conf = i2c_smbus_read_byte_data(new_client, LM73_REG_CONF);
+ if (conf < 0 || (conf & 0x0c))
+ return -ENODEV;
+
+ id = i2c_smbus_read_byte_data(new_client, LM73_REG_ID);
+ if (id < 0 || id != (LM73_ID & 0xff))
+ return -ENODEV;
+
+ /* Check device ID */
+ id = i2c_smbus_read_word_data(new_client, LM73_REG_ID);
+ if (id < 0 || id != LM73_ID)
+ return -ENODEV;
+
+ strlcpy(info->type, "lm73", I2C_NAME_SIZE);
+
+ return 0;
+}
+
+static struct i2c_driver lm73_driver = {
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "lm73",
+ },
+ .probe = lm73_probe,
+ .id_table = lm73_ids,
+ .detect = lm73_detect,
+ .address_list = normal_i2c,
+};
+
+module_i2c_driver(lm73_driver);
+
+MODULE_AUTHOR("Guillaume Ligneul <guillaume.ligneul@gmail.com>");
+MODULE_DESCRIPTION("LM73 driver");
+MODULE_LICENSE("GPL");