Initial import

1 files changed, 560 insertions, 0 deletions

diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
new file mode 100644
index 000000000..fe41d5ae7
--- /dev/null
+++ b/drivers/hwmon/lm75.c
@@ -0,0 +1,560 @@
+/*
+ * lm75.c - Part of lm_sensors, Linux kernel modules for hardware
+ *	 monitoring
+ * Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/thermal.h>
+#include "lm75.h"
+
+
+/*
+ * This driver handles the LM75 and compatible digital temperature sensors.
+ */
+
+enum lm75_type {		/* keep sorted in alphabetical order */
+	adt75,
+	ds1775,
+	ds75,
+	ds7505,
+	g751,
+	lm75,
+	lm75a,
+	lm75b,
+	max6625,
+	max6626,
+	mcp980x,
+	stds75,
+	tcn75,
+	tmp100,
+	tmp101,
+	tmp105,
+	tmp112,
+	tmp175,
+	tmp275,
+	tmp75,
+};
+
+/* Addresses scanned */
+static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
+					0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
+
+
+/* The LM75 registers */
+#define LM75_REG_CONF		0x01
+static const u8 LM75_REG_TEMP[3] = {
+	0x00,		/* input */
+	0x03,		/* max */
+	0x02,		/* hyst */
+};
+
+/* Each client has this additional data */
+struct lm75_data {
+	struct i2c_client	*client;
+	struct device		*hwmon_dev;
+	struct thermal_zone_device	*tz;
+	struct mutex		update_lock;
+	u8			orig_conf;
+	u8			resolution;	/* In bits, between 9 and 12 */
+	u8			resolution_limits;
+	char			valid;		/* !=0 if registers are valid */
+	unsigned long		last_updated;	/* In jiffies */
+	unsigned long		sample_time;	/* In jiffies */
+	s16			temp[3];	/* Register values,
+						   0 = input
+						   1 = max
+						   2 = hyst */
+};
+
+static int lm75_read_value(struct i2c_client *client, u8 reg);
+static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value);
+static struct lm75_data *lm75_update_device(struct device *dev);
+
+
+/*-----------------------------------------------------------------------*/
+
+static inline long lm75_reg_to_mc(s16 temp, u8 resolution)
+{
+	return ((temp >> (16 - resolution)) * 1000) >> (resolution - 8);
+}
+
+/* sysfs attributes for hwmon */
+
+static int lm75_read_temp(void *dev, long *temp)
+{
+	struct lm75_data *data = lm75_update_device(dev);
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
+	*temp = lm75_reg_to_mc(data->temp[0], data->resolution);
+
+	return 0;
+}
+
+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 lm75_data *data = lm75_update_device(dev);
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
+	return sprintf(buf, "%ld\n", lm75_reg_to_mc(data->temp[attr->index],
+						    data->resolution));
+}
+
+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 lm75_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int nr = attr->index;
+	long temp;
+	int error;
+	u8 resolution;
+
+	error = kstrtol(buf, 10, &temp);
+	if (error)
+		return error;
+
+	/*
+	 * Resolution of limit registers is assumed to be the same as the
+	 * temperature input register resolution unless given explicitly.
+	 */
+	if (attr->index && data->resolution_limits)
+		resolution = data->resolution_limits;
+	else
+		resolution = data->resolution;
+
+	mutex_lock(&data->update_lock);
+	temp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
+	data->temp[nr] = DIV_ROUND_CLOSEST(temp  << (resolution - 8),
+					   1000) << (16 - resolution);
+	lm75_write_value(client, LM75_REG_TEMP[nr], data->temp[nr]);
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
+			show_temp, set_temp, 1);
+static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
+			show_temp, set_temp, 2);
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
+
+static struct attribute *lm75_attrs[] = {
+	&sensor_dev_attr_temp1_input.dev_attr.attr,
+	&sensor_dev_attr_temp1_max.dev_attr.attr,
+	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
+
+	NULL
+};
+ATTRIBUTE_GROUPS(lm75);
+
+static const struct thermal_zone_of_device_ops lm75_of_thermal_ops = {
+	.get_temp = lm75_read_temp,
+};
+
+/*-----------------------------------------------------------------------*/
+
+/* device probe and removal */
+
+static int
+lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+	struct device *dev = &client->dev;
+	struct lm75_data *data;
+	int status;
+	u8 set_mask, clr_mask;
+	int new;
+	enum lm75_type kind = id->driver_data;
+
+	if (!i2c_check_functionality(client->adapter,
+			I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
+		return -EIO;
+
+	data = devm_kzalloc(dev, sizeof(struct lm75_data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->client = client;
+	i2c_set_clientdata(client, data);
+	mutex_init(&data->update_lock);
+
+	/* Set to LM75 resolution (9 bits, 1/2 degree C) and range.
+	 * Then tweak to be more precise when appropriate.
+	 */
+	set_mask = 0;
+	clr_mask = LM75_SHUTDOWN;		/* continuous conversions */
+
+	switch (kind) {
+	case adt75:
+		clr_mask |= 1 << 5;		/* not one-shot mode */
+		data->resolution = 12;
+		data->sample_time = HZ / 8;
+		break;
+	case ds1775:
+	case ds75:
+	case stds75:
+		clr_mask |= 3 << 5;
+		set_mask |= 2 << 5;		/* 11-bit mode */
+		data->resolution = 11;
+		data->sample_time = HZ;
+		break;
+	case ds7505:
+		set_mask |= 3 << 5;		/* 12-bit mode */
+		data->resolution = 12;
+		data->sample_time = HZ / 4;
+		break;
+	case g751:
+	case lm75:
+	case lm75a:
+		data->resolution = 9;
+		data->sample_time = HZ / 2;
+		break;
+	case lm75b:
+		data->resolution = 11;
+		data->sample_time = HZ / 4;
+		break;
+	case max6625:
+		data->resolution = 9;
+		data->sample_time = HZ / 4;
+		break;
+	case max6626:
+		data->resolution = 12;
+		data->resolution_limits = 9;
+		data->sample_time = HZ / 4;
+		break;
+	case tcn75:
+		data->resolution = 9;
+		data->sample_time = HZ / 8;
+		break;
+	case mcp980x:
+		data->resolution_limits = 9;
+		/* fall through */
+	case tmp100:
+	case tmp101:
+		set_mask |= 3 << 5;		/* 12-bit mode */
+		data->resolution = 12;
+		data->sample_time = HZ;
+		clr_mask |= 1 << 7;		/* not one-shot mode */
+		break;
+	case tmp112:
+		set_mask |= 3 << 5;		/* 12-bit mode */
+		clr_mask |= 1 << 7;		/* not one-shot mode */
+		data->resolution = 12;
+		data->sample_time = HZ / 4;
+		break;
+	case tmp105:
+	case tmp175:
+	case tmp275:
+	case tmp75:
+		set_mask |= 3 << 5;		/* 12-bit mode */
+		clr_mask |= 1 << 7;		/* not one-shot mode */
+		data->resolution = 12;
+		data->sample_time = HZ / 2;
+		break;
+	}
+
+	/* configure as specified */
+	status = lm75_read_value(client, LM75_REG_CONF);
+	if (status < 0) {
+		dev_dbg(dev, "Can't read config? %d\n", status);
+		return status;
+	}
+	data->orig_conf = status;
+	new = status & ~clr_mask;
+	new |= set_mask;
+	if (status != new)
+		lm75_write_value(client, LM75_REG_CONF, new);
+	dev_dbg(dev, "Config %02x\n", new);
+
+	data->hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
+							    data, lm75_groups);
+	if (IS_ERR(data->hwmon_dev))
+		return PTR_ERR(data->hwmon_dev);
+
+	data->tz = thermal_zone_of_sensor_register(data->hwmon_dev, 0,
+						   data->hwmon_dev,
+						   &lm75_of_thermal_ops);
+	if (IS_ERR(data->tz))
+		data->tz = NULL;
+
+	dev_info(dev, "%s: sensor '%s'\n",
+		 dev_name(data->hwmon_dev), client->name);
+
+	return 0;
+}
+
+static int lm75_remove(struct i2c_client *client)
+{
+	struct lm75_data *data = i2c_get_clientdata(client);
+
+	thermal_zone_of_sensor_unregister(data->hwmon_dev, data->tz);
+	hwmon_device_unregister(data->hwmon_dev);
+	lm75_write_value(client, LM75_REG_CONF, data->orig_conf);
+	return 0;
+}
+
+static const struct i2c_device_id lm75_ids[] = {
+	{ "adt75", adt75, },
+	{ "ds1775", ds1775, },
+	{ "ds75", ds75, },
+	{ "ds7505", ds7505, },
+	{ "g751", g751, },
+	{ "lm75", lm75, },
+	{ "lm75a", lm75a, },
+	{ "lm75b", lm75b, },
+	{ "max6625", max6625, },
+	{ "max6626", max6626, },
+	{ "mcp980x", mcp980x, },
+	{ "stds75", stds75, },
+	{ "tcn75", tcn75, },
+	{ "tmp100", tmp100, },
+	{ "tmp101", tmp101, },
+	{ "tmp105", tmp105, },
+	{ "tmp112", tmp112, },
+	{ "tmp175", tmp175, },
+	{ "tmp275", tmp275, },
+	{ "tmp75", tmp75, },
+	{ /* LIST END */ }
+};
+MODULE_DEVICE_TABLE(i2c, lm75_ids);
+
+#define LM75A_ID 0xA1
+
+/* Return 0 if detection is successful, -ENODEV otherwise */
+static int lm75_detect(struct i2c_client *new_client,
+		       struct i2c_board_info *info)
+{
+	struct i2c_adapter *adapter = new_client->adapter;
+	int i;
+	int conf, hyst, os;
+	bool is_lm75a = 0;
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
+				     I2C_FUNC_SMBUS_WORD_DATA))
+		return -ENODEV;
+
+	/*
+	 * Now, we do the remaining detection. There is no identification-
+	 * dedicated register so we have to rely on several tricks:
+	 * unused bits, registers cycling over 8-address boundaries,
+	 * addresses 0x04-0x07 returning the last read value.
+	 * The cycling+unused addresses combination is not tested,
+	 * since it would significantly slow the detection down and would
+	 * hardly add any value.
+	 *
+	 * The National Semiconductor LM75A is different than earlier
+	 * LM75s.  It has an ID byte of 0xaX (where X is the chip
+	 * revision, with 1 being the only revision in existence) in
+	 * register 7, and unused registers return 0xff rather than the
+	 * last read value.
+	 *
+	 * Note that this function only detects the original National
+	 * Semiconductor LM75 and the LM75A. Clones from other vendors
+	 * aren't detected, on purpose, because they are typically never
+	 * found on PC hardware. They are found on embedded designs where
+	 * they can be instantiated explicitly so detection is not needed.
+	 * The absence of identification registers on all these clones
+	 * would make their exhaustive detection very difficult and weak,
+	 * and odds are that the driver would bind to unsupported devices.
+	 */
+
+	/* Unused bits */
+	conf = i2c_smbus_read_byte_data(new_client, 1);
+	if (conf & 0xe0)
+		return -ENODEV;
+
+	/* First check for LM75A */
+	if (i2c_smbus_read_byte_data(new_client, 7) == LM75A_ID) {
+		/* LM75A returns 0xff on unused registers so
+		   just to be sure we check for that too. */
+		if (i2c_smbus_read_byte_data(new_client, 4) != 0xff
+		 || i2c_smbus_read_byte_data(new_client, 5) != 0xff
+		 || i2c_smbus_read_byte_data(new_client, 6) != 0xff)
+			return -ENODEV;
+		is_lm75a = 1;
+		hyst = i2c_smbus_read_byte_data(new_client, 2);
+		os = i2c_smbus_read_byte_data(new_client, 3);
+	} else { /* Traditional style LM75 detection */
+		/* Unused addresses */
+		hyst = i2c_smbus_read_byte_data(new_client, 2);
+		if (i2c_smbus_read_byte_data(new_client, 4) != hyst
+		 || i2c_smbus_read_byte_data(new_client, 5) != hyst
+		 || i2c_smbus_read_byte_data(new_client, 6) != hyst
+		 || i2c_smbus_read_byte_data(new_client, 7) != hyst)
+			return -ENODEV;
+		os = i2c_smbus_read_byte_data(new_client, 3);
+		if (i2c_smbus_read_byte_data(new_client, 4) != os
+		 || i2c_smbus_read_byte_data(new_client, 5) != os
+		 || i2c_smbus_read_byte_data(new_client, 6) != os
+		 || i2c_smbus_read_byte_data(new_client, 7) != os)
+			return -ENODEV;
+	}
+	/*
+	 * It is very unlikely that this is a LM75 if both
+	 * hysteresis and temperature limit registers are 0.
+	 */
+	if (hyst == 0 && os == 0)
+		return -ENODEV;
+
+	/* Addresses cycling */
+	for (i = 8; i <= 248; i += 40) {
+		if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
+		 || i2c_smbus_read_byte_data(new_client, i + 2) != hyst
+		 || i2c_smbus_read_byte_data(new_client, i + 3) != os)
+			return -ENODEV;
+		if (is_lm75a && i2c_smbus_read_byte_data(new_client, i + 7)
+				!= LM75A_ID)
+			return -ENODEV;
+	}
+
+	strlcpy(info->type, is_lm75a ? "lm75a" : "lm75", I2C_NAME_SIZE);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int lm75_suspend(struct device *dev)
+{
+	int status;
+	struct i2c_client *client = to_i2c_client(dev);
+	status = lm75_read_value(client, LM75_REG_CONF);
+	if (status < 0) {
+		dev_dbg(&client->dev, "Can't read config? %d\n", status);
+		return status;
+	}
+	status = status | LM75_SHUTDOWN;
+	lm75_write_value(client, LM75_REG_CONF, status);
+	return 0;
+}
+
+static int lm75_resume(struct device *dev)
+{
+	int status;
+	struct i2c_client *client = to_i2c_client(dev);
+	status = lm75_read_value(client, LM75_REG_CONF);
+	if (status < 0) {
+		dev_dbg(&client->dev, "Can't read config? %d\n", status);
+		return status;
+	}
+	status = status & ~LM75_SHUTDOWN;
+	lm75_write_value(client, LM75_REG_CONF, status);
+	return 0;
+}
+
+static const struct dev_pm_ops lm75_dev_pm_ops = {
+	.suspend	= lm75_suspend,
+	.resume		= lm75_resume,
+};
+#define LM75_DEV_PM_OPS (&lm75_dev_pm_ops)
+#else
+#define LM75_DEV_PM_OPS NULL
+#endif /* CONFIG_PM */
+
+static struct i2c_driver lm75_driver = {
+	.class		= I2C_CLASS_HWMON,
+	.driver = {
+		.name	= "lm75",
+		.pm	= LM75_DEV_PM_OPS,
+	},
+	.probe		= lm75_probe,
+	.remove		= lm75_remove,
+	.id_table	= lm75_ids,
+	.detect		= lm75_detect,
+	.address_list	= normal_i2c,
+};
+
+/*-----------------------------------------------------------------------*/
+
+/* register access */
+
+/*
+ * All registers are word-sized, except for the configuration register.
+ * LM75 uses a high-byte first convention, which is exactly opposite to
+ * the SMBus standard.
+ */
+static int lm75_read_value(struct i2c_client *client, u8 reg)
+{
+	if (reg == LM75_REG_CONF)
+		return i2c_smbus_read_byte_data(client, reg);
+	else
+		return i2c_smbus_read_word_swapped(client, reg);
+}
+
+static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value)
+{
+	if (reg == LM75_REG_CONF)
+		return i2c_smbus_write_byte_data(client, reg, value);
+	else
+		return i2c_smbus_write_word_swapped(client, reg, value);
+}
+
+static struct lm75_data *lm75_update_device(struct device *dev)
+{
+	struct lm75_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	struct lm75_data *ret = data;
+
+	mutex_lock(&data->update_lock);
+
+	if (time_after(jiffies, data->last_updated + data->sample_time)
+	    || !data->valid) {
+		int i;
+		dev_dbg(&client->dev, "Starting lm75 update\n");
+
+		for (i = 0; i < ARRAY_SIZE(data->temp); i++) {
+			int status;
+
+			status = lm75_read_value(client, LM75_REG_TEMP[i]);
+			if (unlikely(status < 0)) {
+				dev_dbg(dev,
+					"LM75: Failed to read value: reg %d, error %d\n",
+					LM75_REG_TEMP[i], status);
+				ret = ERR_PTR(status);
+				data->valid = 0;
+				goto abort;
+			}
+			data->temp[i] = status;
+		}
+		data->last_updated = jiffies;
+		data->valid = 1;
+	}
+
+abort:
+	mutex_unlock(&data->update_lock);
+	return ret;
+}
+
+module_i2c_driver(lm75_driver);
+
+MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
+MODULE_DESCRIPTION("LM75 driver");
+MODULE_LICENSE("GPL");