1 files changed, 290 insertions, 0 deletions
diff --git a/drivers/hwmon/lm73.c b/drivers/hwmon/lm73.c
new file mode 100644
index 000000000..1346b3b3f
--- /dev/null
+++ b/drivers/hwmon/lm73.c
@@ -0,0 +1,290 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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>
+ */
+
+#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 temp_store(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 temp_show(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 convrate_store(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 convrate_show(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 maxmin_alarm_show(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_RW(temp1_max, temp, LM73_REG_MAX);
+static SENSOR_DEVICE_ATTR_RW(temp1_min, temp, LM73_REG_MIN);
+static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, LM73_REG_INPUT);
+static SENSOR_DEVICE_ATTR_RW(update_interval, convrate, 0);
+static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, maxmin_alarm,
+			     LM73_CTRL_HI_SHIFT);
+static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, maxmin_alarm,
+			     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)
+{
+	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;
+
+	strscpy(info->type, "lm73", I2C_NAME_SIZE);
+
+	return 0;
+}
+
+static const struct of_device_id lm73_of_match[] = {
+	{
+		.compatible = "ti,lm73",
+	},
+	{ },
+};
+
+MODULE_DEVICE_TABLE(of, lm73_of_match);
+
+static struct i2c_driver lm73_driver = {
+	.class		= I2C_CLASS_HWMON,
+	.driver = {
+		.name	= "lm73",
+		.of_match_table = lm73_of_match,
+	},
+	.probe_new	= 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");