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Diffstat (limited to 'drivers/hwmon/ds1621.c')
-rw-r--r--drivers/hwmon/ds1621.c226
1 files changed, 172 insertions, 54 deletions
diff --git a/drivers/hwmon/ds1621.c b/drivers/hwmon/ds1621.c
index 1c568736baf..a26ba7a17c2 100644
--- a/drivers/hwmon/ds1621.c
+++ b/drivers/hwmon/ds1621.c
@@ -6,6 +6,19 @@
* Ported to Linux 2.6 by Aurelien Jarno <aurelien@aurel32.net> with
* the help of Jean Delvare <khali@linux-fr.org>
*
+ * 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
@@ -31,27 +44,62 @@
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/sysfs.h>
-#include "lm75.h"
+#include <linux/kernel.h>
-/* Addresses to scan */
-static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
- 0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
+/* 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");
-/* Many DS1621 constants specified below */
-/* Config register used for detection */
-/* 7 6 5 4 3 2 1 0 */
-/* |Done|THF |TLF |NVB | X | X |POL |1SHOT| */
+/*
+ * 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
-/* The DS1621 registers */
+#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 */
@@ -59,6 +107,7 @@ static const u8 DS1621_REG_TEMP[3] = {
};
#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 */
@@ -75,14 +124,37 @@ struct ds1621_data {
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 i2c_client *client)
{
- u8 conf, new_conf;
+ u8 conf, new_conf, sreg, resol;
+ struct ds1621_data *data = i2c_get_clientdata(client);
new_conf = conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF);
/* switch to continuous conversion mode */
@@ -97,8 +169,30 @@ static void ds1621_init_client(struct i2c_client *client)
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, DS1621_COM_START);
+ i2c_smbus_write_byte(client, sreg);
}
static struct ds1621_data *ds1621_update_client(struct device *dev)
@@ -109,8 +203,8 @@ static struct ds1621_data *ds1621_update_client(struct device *dev)
mutex_lock(&data->update_lock);
- if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
- || !data->valid) {
+ if (time_after(jiffies, data->last_updated + data->update_interval) ||
+ !data->valid) {
int i;
dev_dbg(&client->dev, "Starting ds1621 update\n");
@@ -146,7 +240,7 @@ static ssize_t show_temp(struct device *dev, struct device_attribute *da,
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct ds1621_data *data = ds1621_update_client(dev);
return sprintf(buf, "%d\n",
- LM75_TEMP_FROM_REG(data->temp[attr->index]));
+ DS1621_TEMP_FROM_REG(data->temp[attr->index]));
}
static ssize_t set_temp(struct device *dev, struct device_attribute *da,
@@ -163,7 +257,7 @@ static ssize_t set_temp(struct device *dev, struct device_attribute *da,
return err;
mutex_lock(&data->update_lock);
- data->temp[attr->index] = LM75_TEMP_TO_REG(val);
+ data->temp[attr->index] = DS1621_TEMP_TO_REG(val, data->zbits);
i2c_smbus_write_word_swapped(client, DS1621_REG_TEMP[attr->index],
data->temp[attr->index]);
mutex_unlock(&data->update_lock);
@@ -185,7 +279,47 @@ static ssize_t show_alarm(struct device *dev, struct device_attribute *da,
return sprintf(buf, "%d\n", !!(data->conf & attr->index));
}
+static ssize_t show_convrate(struct device *dev, struct device_attribute *da,
+ char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ds1621_data *data = i2c_get_clientdata(client);
+ return scnprintf(buf, PAGE_SIZE, "%hu\n", data->update_interval);
+}
+
+static ssize_t set_convrate(struct device *dev, struct device_attribute *da,
+ const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ds1621_data *data = i2c_get_clientdata(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];
+ mutex_unlock(&data->update_lock);
+
+ return count;
+}
+
static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
+static DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO, show_convrate,
+ set_convrate);
+
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);
@@ -201,48 +335,29 @@ static struct attribute *ds1621_attributes[] = {
&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 const struct attribute_group ds1621_group = {
- .attrs = ds1621_attributes,
-};
-
-
-/* Return 0 if detection is successful, -ENODEV otherwise */
-static int ds1621_detect(struct i2c_client *client,
- struct i2c_board_info *info)
+static umode_t ds1621_attribute_visible(struct kobject *kobj,
+ struct attribute *attr, int index)
{
- struct i2c_adapter *adapter = client->adapter;
- int conf, temp;
- int i;
-
- if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
- | I2C_FUNC_SMBUS_WORD_DATA
- | I2C_FUNC_SMBUS_WRITE_BYTE))
- return -ENODEV;
-
- /*
- * Now, we do the remaining detection. It is lousy.
- *
- * The NVB bit should be low if no EEPROM write has been requested
- * during the latest 10ms, which is highly improbable in our case.
- */
- conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF);
- if (conf < 0 || conf & DS1621_REG_CONFIG_NVB)
- return -ENODEV;
- /* The 7 lowest bits of a temperature should always be 0. */
- for (i = 0; i < ARRAY_SIZE(DS1621_REG_TEMP); i++) {
- temp = i2c_smbus_read_word_data(client, DS1621_REG_TEMP[i]);
- if (temp < 0 || (temp & 0x7f00))
- return -ENODEV;
- }
-
- strlcpy(info->type, "ds1621", I2C_NAME_SIZE);
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ds1621_data *data = i2c_get_clientdata(client);
- return 0;
+ 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
+};
+
static int ds1621_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
@@ -257,6 +372,8 @@ static int ds1621_probe(struct i2c_client *client,
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
+ data->kind = id->driver_data;
+
/* Initialize the DS1621 chip */
ds1621_init_client(client);
@@ -289,8 +406,11 @@ static int ds1621_remove(struct i2c_client *client)
}
static const struct i2c_device_id ds1621_id[] = {
- { "ds1621", 0 },
- { "ds1625", 0 },
+ { "ds1621", ds1621 },
+ { "ds1625", ds1625 },
+ { "ds1631", ds1631 },
+ { "ds1721", ds1721 },
+ { "ds1731", ds1731 },
{ }
};
MODULE_DEVICE_TABLE(i2c, ds1621_id);
@@ -304,8 +424,6 @@ static struct i2c_driver ds1621_driver = {
.probe = ds1621_probe,
.remove = ds1621_remove,
.id_table = ds1621_id,
- .detect = ds1621_detect,
- .address_list = normal_i2c,
};
module_i2c_driver(ds1621_driver);