提交 cd6c8a42 编写于 作者: R Robert Coulson 提交者: Guenter Roeck

hwmon: (ds1621) Add ds1721 chip support

Update the ds1621 documentation, driver, and Kconfig with
ds1721 chip support.
Signed-off-by: NRobert Coulson <rob.coulson@gmail.com>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
上级 cd275a56
......@@ -2,16 +2,22 @@ Kernel driver ds1621
====================
Supported chips:
* Dallas Semiconductor DS1621
* Dallas Semiconductor / Maxim Integrated DS1621
Prefix: 'ds1621'
Addresses scanned: I2C 0x48 - 0x4f
Datasheet: Publicly available at the Dallas Semiconductor website
http://www.dalsemi.com/
Datasheet: Publicly available from www.maximintegrated.com
* Dallas Semiconductor DS1625
Prefix: 'ds1621'
Prefix:
'ds1621' - if binding via _detect function
'ds1625' - explicit instantiation
Addresses scanned: I2C 0x48 - 0x4f
Datasheet: Publicly available from www.datasheetarchive.com
* Maxim Integrated DS1721
Prefix: 'ds1721'
Addresses scanned: I2C 0x48 - 0x4f
Datasheet: Publicly available at the Dallas Semiconductor website
http://www.dalsemi.com/
Datasheet: Publicly available from www.maximintegrated.com
Authors:
Christian W. Zuckschwerdt <zany@triq.net>
......@@ -61,3 +67,11 @@ with neither of the alarms set.
Temperature conversion of the DS1621 takes up to 1000ms; internal access to
non-volatile registers may last for 10ms or below.
The DS1625 is pin compatible and functionally equivalent with the DS1621,
but the DS1621 is meant to replace it.
The DS1721 is pin compatible with the DS1621, has an accuracy of +/- 1.0
degree Celsius over a -10 to +85 degree range, a minimum/maximum alarm
default setting of 75 and 80 degrees respectively, and a maximum conversion
time of 750ms.
......@@ -348,11 +348,14 @@ config SENSORS_DS620
will be called ds620.
config SENSORS_DS1621
tristate "Dallas Semiconductor DS1621 and DS1625"
tristate "Dallas Semiconductor DS1621 and compatibles"
depends on I2C
help
If you say yes here you get support for Dallas Semiconductor
DS1621 and DS1625 sensor chips.
If you say yes here you get support for Dallas Semiconductor/Maxim
Integrated DS1621 sensor chips and compatible models including:
- Dallas Semiconductor DS1625
- Maxim Integrated DS1721
This driver can also be built as a module. If so, the module
will be called ds1621.
......
......@@ -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 and DS1721 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, ds1721 };
/* 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|
*
* - 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 */
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: x = 0.5C
* - 1721: x = 0.0625C
* Assume highest resolution and let the bits fall where they may..
*/
static inline u16 DS1621_TEMP_TO_REG(long temp)
{
int ntemp = clamp_val(temp, DS1621_TEMP_MIN, DS1621_TEMP_MAX);
ntemp += (ntemp < 0 ? -31 : 31);
ntemp = DIV_ROUND_CLOSEST(ntemp * 10, 625) << 4;
return (u16)ntemp;
}
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 +169,25 @@ 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;
sreg = DS1621_COM_START;
break;
case ds1721:
resol = (new_conf & DS1621_REG_CONFIG_RESOL) >>
DS1621_REG_CONFIG_RESOL_SHIFT;
data->update_interval = ds1721_convrates[resol];
sreg = DS1721_COM_START;
break;
default:
data->update_interval = DS1621_CONVERSION_MAX;
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 +198,8 @@ 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 +235,7 @@ 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 +252,7 @@ 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);
i2c_smbus_write_word_swapped(client, DS1621_REG_TEMP[attr->index],
data->temp[attr->index]);
mutex_unlock(&data->update_lock);
......@@ -257,6 +346,8 @@ 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 +380,9 @@ static int ds1621_remove(struct i2c_client *client)
}
static const struct i2c_device_id ds1621_id[] = {
{ "ds1621", 0 },
{ "ds1625", 0 },
{ "ds1621", ds1621 },
{ "ds1625", ds1625 },
{ "ds1721", ds1721 },
{ }
};
MODULE_DEVICE_TABLE(i2c, ds1621_id);
......
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