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-rw-r--r--drivers/hwmon/ds1621.c409
1 files changed, 409 insertions, 0 deletions
diff --git a/drivers/hwmon/ds1621.c b/drivers/hwmon/ds1621.c
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index 000000000..5c317fc32
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+++ b/drivers/hwmon/ds1621.c
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+/*
+ * ds1621.c - Part of lm_sensors, Linux kernel modules for hardware
+ * monitoring
+ * Christian W. Zuckschwerdt <zany@triq.net> 2000-11-23
+ * based on lm75.c by Frodo Looijaard <frodol@dds.nl>
+ * Ported to Linux 2.6 by Aurelien Jarno <aurelien@aurel32.net> with
+ * the help of Jean Delvare <jdelvare@suse.de>
+ *
+ * The DS1621 device is a digital temperature/thermometer with 9-bit
+ * resolution, a thermal alarm output (Tout), and user-defined minimum
+ * and maximum temperature thresholds (TH and TL).
+ *
+ * The DS1625, DS1631, DS1721, and DS1731 are pin compatible with the DS1621
+ * and similar in operation, with slight variations as noted in the device
+ * datasheets (please refer to www.maximintegrated.com for specific
+ * device information).
+ *
+ * Since the DS1621 was the first chipset supported by this driver,
+ * most comments will refer to this chipset, but are actually general
+ * and concern all supported chipsets, unless mentioned otherwise.
+ *
+ * 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/sysfs.h>
+#include <linux/kernel.h>
+
+/* Supported devices */
+enum chips { ds1621, ds1625, ds1631, ds1721, ds1731 };
+
+/* Insmod parameters */
+static int polarity = -1;
+module_param(polarity, int, 0);
+MODULE_PARM_DESC(polarity, "Output's polarity: 0 = active high, 1 = active low");
+
+/*
+ * The Configuration/Status register
+ *
+ * - DS1621:
+ * 7 6 5 4 3 2 1 0
+ * |Done|THF |TLF |NVB | X | X |POL |1SHOT|
+ *
+ * - DS1625:
+ * 7 6 5 4 3 2 1 0
+ * |Done|THF |TLF |NVB | 1 | 0 |POL |1SHOT|
+ *
+ * - DS1631, DS1731:
+ * 7 6 5 4 3 2 1 0
+ * |Done|THF |TLF |NVB | R1 | R0 |POL |1SHOT|
+ *
+ * - DS1721:
+ * 7 6 5 4 3 2 1 0
+ * |Done| X | X | U | R1 | R0 |POL |1SHOT|
+ *
+ * Where:
+ * - 'X' is Reserved
+ * - 'U' is Undefined
+ */
+#define DS1621_REG_CONFIG_NVB 0x10
+#define DS1621_REG_CONFIG_RESOL 0x0C
+#define DS1621_REG_CONFIG_POLARITY 0x02
+#define DS1621_REG_CONFIG_1SHOT 0x01
+#define DS1621_REG_CONFIG_DONE 0x80
+
+#define DS1621_REG_CONFIG_RESOL_SHIFT 2
+
+/* ds1721 conversion rates: {C/LSB, time(ms), resolution bit setting} */
+static const unsigned short ds1721_convrates[] = {
+ 94, /* 9-bits (0.5, 93.75, RES[0..1] = 0 */
+ 188, /* 10-bits (0.25, 187.5, RES[0..1] = 1 */
+ 375, /* 11-bits (0.125, 375, RES[0..1] = 2 */
+ 750, /* 12-bits (0.0625, 750, RES[0..1] = 3 */
+};
+
+#define DS1621_CONVERSION_MAX 750
+#define DS1625_CONVERSION_MAX 500
+
+#define DS1621_TEMP_MAX 125000
+#define DS1621_TEMP_MIN (-55000)
+
+/* The DS1621 temperature registers */
+static const u8 DS1621_REG_TEMP[3] = {
+ 0xAA, /* input, word, RO */
+ 0xA2, /* min, word, RW */
+ 0xA1, /* max, word, RW */
+};
+#define DS1621_REG_CONF 0xAC /* byte, RW */
+#define DS1621_COM_START 0xEE /* no data */
+#define DS1721_COM_START 0x51 /* no data */
+#define DS1621_COM_STOP 0x22 /* no data */
+
+/* The DS1621 configuration register */
+#define DS1621_ALARM_TEMP_HIGH 0x40
+#define DS1621_ALARM_TEMP_LOW 0x20
+
+/* Conversions */
+#define ALARMS_FROM_REG(val) ((val) & \
+ (DS1621_ALARM_TEMP_HIGH | DS1621_ALARM_TEMP_LOW))
+
+/* Each client has this additional data */
+struct ds1621_data {
+ struct i2c_client *client;
+ struct mutex update_lock;
+ char valid; /* !=0 if following fields are valid */
+ unsigned long last_updated; /* In jiffies */
+ enum chips kind; /* device type */
+
+ u16 temp[3]; /* Register values, word */
+ u8 conf; /* Register encoding, combined */
+ u8 zbits; /* Resolution encoded as number of
+ * zero bits */
+ u16 update_interval; /* Conversion rate in milliseconds */
+};
+
+static inline int DS1621_TEMP_FROM_REG(u16 reg)
+{
+ return DIV_ROUND_CLOSEST(((s16)reg / 16) * 625, 10);
+}
+
+/*
+ * TEMP: 0.001C/bit (-55C to +125C)
+ * REG:
+ * - 1621, 1625: 0.5C/bit, 7 zero-bits
+ * - 1631, 1721, 1731: 0.0625C/bit, 4 zero-bits
+ */
+static inline u16 DS1621_TEMP_TO_REG(long temp, u8 zbits)
+{
+ temp = clamp_val(temp, DS1621_TEMP_MIN, DS1621_TEMP_MAX);
+ temp = DIV_ROUND_CLOSEST(temp * (1 << (8 - zbits)), 1000) << zbits;
+ return temp;
+}
+
+static void ds1621_init_client(struct ds1621_data *data,
+ struct i2c_client *client)
+{
+ u8 conf, new_conf, sreg, resol;
+
+ new_conf = conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF);
+ /* switch to continuous conversion mode */
+ new_conf &= ~DS1621_REG_CONFIG_1SHOT;
+
+ /* setup output polarity */
+ if (polarity == 0)
+ new_conf &= ~DS1621_REG_CONFIG_POLARITY;
+ else if (polarity == 1)
+ new_conf |= DS1621_REG_CONFIG_POLARITY;
+
+ if (conf != new_conf)
+ i2c_smbus_write_byte_data(client, DS1621_REG_CONF, new_conf);
+
+ switch (data->kind) {
+ case ds1625:
+ data->update_interval = DS1625_CONVERSION_MAX;
+ data->zbits = 7;
+ sreg = DS1621_COM_START;
+ break;
+ case ds1631:
+ case ds1721:
+ case ds1731:
+ resol = (new_conf & DS1621_REG_CONFIG_RESOL) >>
+ DS1621_REG_CONFIG_RESOL_SHIFT;
+ data->update_interval = ds1721_convrates[resol];
+ data->zbits = 7 - resol;
+ sreg = DS1721_COM_START;
+ break;
+ default:
+ data->update_interval = DS1621_CONVERSION_MAX;
+ data->zbits = 7;
+ sreg = DS1621_COM_START;
+ break;
+ }
+
+ /* start conversion */
+ i2c_smbus_write_byte(client, sreg);
+}
+
+static struct ds1621_data *ds1621_update_client(struct device *dev)
+{
+ struct ds1621_data *data = dev_get_drvdata(dev);
+ struct i2c_client *client = data->client;
+ u8 new_conf;
+
+ mutex_lock(&data->update_lock);
+
+ if (time_after(jiffies, data->last_updated + data->update_interval) ||
+ !data->valid) {
+ int i;
+
+ dev_dbg(&client->dev, "Starting ds1621 update\n");
+
+ data->conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF);
+
+ for (i = 0; i < ARRAY_SIZE(data->temp); i++)
+ data->temp[i] = i2c_smbus_read_word_swapped(client,
+ DS1621_REG_TEMP[i]);
+
+ /* reset alarms if necessary */
+ new_conf = data->conf;
+ if (data->temp[0] > data->temp[1]) /* input > min */
+ new_conf &= ~DS1621_ALARM_TEMP_LOW;
+ if (data->temp[0] < data->temp[2]) /* input < max */
+ new_conf &= ~DS1621_ALARM_TEMP_HIGH;
+ if (data->conf != new_conf)
+ i2c_smbus_write_byte_data(client, DS1621_REG_CONF,
+ new_conf);
+
+ data->last_updated = jiffies;
+ data->valid = 1;
+ }
+
+ mutex_unlock(&data->update_lock);
+
+ return data;
+}
+
+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 ds1621_data *data = ds1621_update_client(dev);
+ return sprintf(buf, "%d\n",
+ DS1621_TEMP_FROM_REG(data->temp[attr->index]));
+}
+
+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 ds1621_data *data = dev_get_drvdata(dev);
+ long val;
+ int err;
+
+ err = kstrtol(buf, 10, &val);
+ if (err)
+ return err;
+
+ mutex_lock(&data->update_lock);
+ data->temp[attr->index] = DS1621_TEMP_TO_REG(val, data->zbits);
+ i2c_smbus_write_word_swapped(data->client, DS1621_REG_TEMP[attr->index],
+ data->temp[attr->index]);
+ mutex_unlock(&data->update_lock);
+ return count;
+}
+
+static ssize_t alarms_show(struct device *dev, struct device_attribute *da,
+ char *buf)
+{
+ struct ds1621_data *data = ds1621_update_client(dev);
+ return sprintf(buf, "%d\n", ALARMS_FROM_REG(data->conf));
+}
+
+static ssize_t show_alarm(struct device *dev, struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ struct ds1621_data *data = ds1621_update_client(dev);
+ return sprintf(buf, "%d\n", !!(data->conf & attr->index));
+}
+
+static ssize_t update_interval_show(struct device *dev,
+ struct device_attribute *da, char *buf)
+{
+ struct ds1621_data *data = dev_get_drvdata(dev);
+ return scnprintf(buf, PAGE_SIZE, "%hu\n", data->update_interval);
+}
+
+static ssize_t update_interval_store(struct device *dev,
+ struct device_attribute *da,
+ const char *buf, size_t count)
+{
+ struct ds1621_data *data = dev_get_drvdata(dev);
+ struct i2c_client *client = data->client;
+ unsigned long convrate;
+ s32 err;
+ int resol = 0;
+
+ err = kstrtoul(buf, 10, &convrate);
+ if (err)
+ return err;
+
+ /* Convert rate into resolution bits */
+ while (resol < (ARRAY_SIZE(ds1721_convrates) - 1) &&
+ convrate > ds1721_convrates[resol])
+ resol++;
+
+ mutex_lock(&data->update_lock);
+ data->conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF);
+ data->conf &= ~DS1621_REG_CONFIG_RESOL;
+ data->conf |= (resol << DS1621_REG_CONFIG_RESOL_SHIFT);
+ i2c_smbus_write_byte_data(client, DS1621_REG_CONF, data->conf);
+ data->update_interval = ds1721_convrates[resol];
+ data->zbits = 7 - resol;
+ mutex_unlock(&data->update_lock);
+
+ return count;
+}
+
+static DEVICE_ATTR_RO(alarms);
+static DEVICE_ATTR_RW(update_interval);
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp, set_temp, 1);
+static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp, set_temp, 2);
+static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL,
+ DS1621_ALARM_TEMP_LOW);
+static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL,
+ DS1621_ALARM_TEMP_HIGH);
+
+static struct attribute *ds1621_attributes[] = {
+ &sensor_dev_attr_temp1_input.dev_attr.attr,
+ &sensor_dev_attr_temp1_min.dev_attr.attr,
+ &sensor_dev_attr_temp1_max.dev_attr.attr,
+ &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
+ &dev_attr_alarms.attr,
+ &dev_attr_update_interval.attr,
+ NULL
+};
+
+static umode_t ds1621_attribute_visible(struct kobject *kobj,
+ struct attribute *attr, int index)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct ds1621_data *data = dev_get_drvdata(dev);
+
+ if (attr == &dev_attr_update_interval.attr)
+ if (data->kind == ds1621 || data->kind == ds1625)
+ /* shhh, we're hiding update_interval */
+ return 0;
+ return attr->mode;
+}
+
+static const struct attribute_group ds1621_group = {
+ .attrs = ds1621_attributes,
+ .is_visible = ds1621_attribute_visible
+};
+__ATTRIBUTE_GROUPS(ds1621);
+
+static int ds1621_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct ds1621_data *data;
+ struct device *hwmon_dev;
+
+ data = devm_kzalloc(&client->dev, sizeof(struct ds1621_data),
+ GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ mutex_init(&data->update_lock);
+
+ data->kind = id->driver_data;
+ data->client = client;
+
+ /* Initialize the DS1621 chip */
+ ds1621_init_client(data, client);
+
+ hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev,
+ client->name, data,
+ ds1621_groups);
+ return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static const struct i2c_device_id ds1621_id[] = {
+ { "ds1621", ds1621 },
+ { "ds1625", ds1625 },
+ { "ds1631", ds1631 },
+ { "ds1721", ds1721 },
+ { "ds1731", ds1731 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ds1621_id);
+
+/* This is the driver that will be inserted */
+static struct i2c_driver ds1621_driver = {
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "ds1621",
+ },
+ .probe = ds1621_probe,
+ .id_table = ds1621_id,
+};
+
+module_i2c_driver(ds1621_driver);
+
+MODULE_AUTHOR("Christian W. Zuckschwerdt <zany@triq.net>");
+MODULE_DESCRIPTION("DS1621 driver");
+MODULE_LICENSE("GPL");
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