diff options
Diffstat (limited to 'drivers/hwmon/ds1621.c')
| -rw-r--r-- | drivers/hwmon/ds1621.c | 226 |
1 files changed, 172 insertions, 54 deletions
diff --git a/drivers/hwmon/ds1621.c b/drivers/hwmon/ds1621.c index 1c568736baff..a26ba7a17c2b 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); |