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kernel-ark/drivers/i2c/chips/lm90.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2 
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

627 lines
20 KiB
C
Raw Blame History

/*
* lm90.c - Part of lm_sensors, Linux kernel modules for hardware
* monitoring
* Copyright (C) 2003-2004 Jean Delvare <khali@linux-fr.org>
*
* Based on the lm83 driver. The LM90 is a sensor chip made by National
* Semiconductor. It reports up to two temperatures (its own plus up to
* one external one) with a 0.125 deg resolution (1 deg for local
* temperature) and a 3-4 deg accuracy. Complete datasheet can be
* obtained from National's website at:
* http://www.national.com/pf/LM/LM90.html
*
* This driver also supports the LM89 and LM99, two other sensor chips
* made by National Semiconductor. Both have an increased remote
* temperature measurement accuracy (1 degree), and the LM99
* additionally shifts remote temperatures (measured and limits) by 16
* degrees, which allows for higher temperatures measurement. The
* driver doesn't handle it since it can be done easily in user-space.
* Complete datasheets can be obtained from National's website at:
* http://www.national.com/pf/LM/LM89.html
* http://www.national.com/pf/LM/LM99.html
* Note that there is no way to differenciate between both chips.
*
* This driver also supports the LM86, another sensor chip made by
* National Semiconductor. It is exactly similar to the LM90 except it
* has a higher accuracy.
* Complete datasheet can be obtained from National's website at:
* http://www.national.com/pf/LM/LM86.html
*
* This driver also supports the ADM1032, a sensor chip made by Analog
* Devices. That chip is similar to the LM90, with a few differences
* that are not handled by this driver. Complete datasheet can be
* obtained from Analog's website at:
* http://products.analog.com/products/info.asp?product=ADM1032
* Among others, it has a higher accuracy than the LM90, much like the
* LM86 does.
*
* This driver also supports the MAX6657, MAX6658 and MAX6659 sensor
* chips made by Maxim. These chips are similar to the LM86. Complete
* datasheet can be obtained at Maxim's website at:
* http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2578
* Note that there is no easy way to differenciate between the three
* variants. The extra address and features of the MAX6659 are not
* supported by this driver.
*
* This driver also supports the ADT7461 chip from Analog Devices but
* only in its "compatability mode". If an ADT7461 chip is found but
* is configured in non-compatible mode (where its temperature
* register values are decoded differently) it is ignored by this
* driver. Complete datasheet can be obtained from Analog's website
* at:
* http://products.analog.com/products/info.asp?product=ADT7461
*
* Since the LM90 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/config.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/i2c-sensor.h>
/*
* Addresses to scan
* Address is fully defined internally and cannot be changed except for
* MAX6659.
* LM86, LM89, LM90, LM99, ADM1032, MAX6657 and MAX6658 have address 0x4c.
* LM89-1, and LM99-1 have address 0x4d.
* MAX6659 can have address 0x4c, 0x4d or 0x4e (unsupported).
* ADT7461 always has address 0x4c.
*/
static unsigned short normal_i2c[] = { 0x4c, 0x4d, I2C_CLIENT_END };
static unsigned int normal_isa[] = { I2C_CLIENT_ISA_END };
/*
* Insmod parameters
*/
SENSORS_INSMOD_6(lm90, adm1032, lm99, lm86, max6657, adt7461);
/*
* The LM90 registers
*/
#define LM90_REG_R_MAN_ID 0xFE
#define LM90_REG_R_CHIP_ID 0xFF
#define LM90_REG_R_CONFIG1 0x03
#define LM90_REG_W_CONFIG1 0x09
#define LM90_REG_R_CONFIG2 0xBF
#define LM90_REG_W_CONFIG2 0xBF
#define LM90_REG_R_CONVRATE 0x04
#define LM90_REG_W_CONVRATE 0x0A
#define LM90_REG_R_STATUS 0x02
#define LM90_REG_R_LOCAL_TEMP 0x00
#define LM90_REG_R_LOCAL_HIGH 0x05
#define LM90_REG_W_LOCAL_HIGH 0x0B
#define LM90_REG_R_LOCAL_LOW 0x06
#define LM90_REG_W_LOCAL_LOW 0x0C
#define LM90_REG_R_LOCAL_CRIT 0x20
#define LM90_REG_W_LOCAL_CRIT 0x20
#define LM90_REG_R_REMOTE_TEMPH 0x01
#define LM90_REG_R_REMOTE_TEMPL 0x10
#define LM90_REG_R_REMOTE_OFFSH 0x11
#define LM90_REG_W_REMOTE_OFFSH 0x11
#define LM90_REG_R_REMOTE_OFFSL 0x12
#define LM90_REG_W_REMOTE_OFFSL 0x12
#define LM90_REG_R_REMOTE_HIGHH 0x07
#define LM90_REG_W_REMOTE_HIGHH 0x0D
#define LM90_REG_R_REMOTE_HIGHL 0x13
#define LM90_REG_W_REMOTE_HIGHL 0x13
#define LM90_REG_R_REMOTE_LOWH 0x08
#define LM90_REG_W_REMOTE_LOWH 0x0E
#define LM90_REG_R_REMOTE_LOWL 0x14
#define LM90_REG_W_REMOTE_LOWL 0x14
#define LM90_REG_R_REMOTE_CRIT 0x19
#define LM90_REG_W_REMOTE_CRIT 0x19
#define LM90_REG_R_TCRIT_HYST 0x21
#define LM90_REG_W_TCRIT_HYST 0x21
/*
* Conversions and various macros
* For local temperatures and limits, critical limits and the hysteresis
* value, the LM90 uses signed 8-bit values with LSB = 1 degree Celcius.
* For remote temperatures and limits, it uses signed 11-bit values with
* LSB = 0.125 degree Celcius, left-justified in 16-bit registers.
*/
#define TEMP1_FROM_REG(val) ((val) * 1000)
#define TEMP1_TO_REG(val) ((val) <= -128000 ? -128 : \
(val) >= 127000 ? 127 : \
(val) < 0 ? ((val) - 500) / 1000 : \
((val) + 500) / 1000)
#define TEMP2_FROM_REG(val) ((val) / 32 * 125)
#define TEMP2_TO_REG(val) ((val) <= -128000 ? 0x8000 : \
(val) >= 127875 ? 0x7FE0 : \
(val) < 0 ? ((val) - 62) / 125 * 32 : \
((val) + 62) / 125 * 32)
#define HYST_TO_REG(val) ((val) <= 0 ? 0 : (val) >= 30500 ? 31 : \
((val) + 500) / 1000)
/*
* ADT7461 is almost identical to LM90 except that attempts to write
* values that are outside the range 0 < temp < 127 are treated as
* the boundary value.
*/
#define TEMP1_TO_REG_ADT7461(val) ((val) <= 0 ? 0 : \
(val) >= 127000 ? 127 : \
((val) + 500) / 1000)
#define TEMP2_TO_REG_ADT7461(val) ((val) <= 0 ? 0 : \
(val) >= 127750 ? 0x7FC0 : \
((val) + 125) / 250 * 64)
/*
* Functions declaration
*/
static int lm90_attach_adapter(struct i2c_adapter *adapter);
static int lm90_detect(struct i2c_adapter *adapter, int address,
int kind);
static void lm90_init_client(struct i2c_client *client);
static int lm90_detach_client(struct i2c_client *client);
static struct lm90_data *lm90_update_device(struct device *dev);
/*
* Driver data (common to all clients)
*/
static struct i2c_driver lm90_driver = {
.owner = THIS_MODULE,
.name = "lm90",
.id = I2C_DRIVERID_LM90,
.flags = I2C_DF_NOTIFY,
.attach_adapter = lm90_attach_adapter,
.detach_client = lm90_detach_client,
};
/*
* Client data (each client gets its own)
*/
struct lm90_data {
struct i2c_client client;
struct semaphore update_lock;
char valid; /* zero until following fields are valid */
unsigned long last_updated; /* in jiffies */
int kind;
/* registers values */
s8 temp_input1, temp_low1, temp_high1; /* local */
s16 temp_input2, temp_low2, temp_high2; /* remote, combined */
s8 temp_crit1, temp_crit2;
u8 temp_hyst;
u8 alarms; /* bitvector */
};
/*
* Sysfs stuff
*/
#define show_temp(value, converter) \
static ssize_t show_##value(struct device *dev, char *buf) \
{ \
struct lm90_data *data = lm90_update_device(dev); \
return sprintf(buf, "%d\n", converter(data->value)); \
}
show_temp(temp_input1, TEMP1_FROM_REG);
show_temp(temp_input2, TEMP2_FROM_REG);
show_temp(temp_low1, TEMP1_FROM_REG);
show_temp(temp_low2, TEMP2_FROM_REG);
show_temp(temp_high1, TEMP1_FROM_REG);
show_temp(temp_high2, TEMP2_FROM_REG);
show_temp(temp_crit1, TEMP1_FROM_REG);
show_temp(temp_crit2, TEMP1_FROM_REG);
#define set_temp1(value, reg) \
static ssize_t set_##value(struct device *dev, const char *buf, \
size_t count) \
{ \
struct i2c_client *client = to_i2c_client(dev); \
struct lm90_data *data = i2c_get_clientdata(client); \
long val = simple_strtol(buf, NULL, 10); \
\
down(&data->update_lock); \
if (data->kind == adt7461) \
data->value = TEMP1_TO_REG_ADT7461(val); \
else \
data->value = TEMP1_TO_REG(val); \
i2c_smbus_write_byte_data(client, reg, data->value); \
up(&data->update_lock); \
return count; \
}
#define set_temp2(value, regh, regl) \
static ssize_t set_##value(struct device *dev, const char *buf, \
size_t count) \
{ \
struct i2c_client *client = to_i2c_client(dev); \
struct lm90_data *data = i2c_get_clientdata(client); \
long val = simple_strtol(buf, NULL, 10); \
\
down(&data->update_lock); \
if (data->kind == adt7461) \
data->value = TEMP2_TO_REG_ADT7461(val); \
else \
data->value = TEMP2_TO_REG(val); \
i2c_smbus_write_byte_data(client, regh, data->value >> 8); \
i2c_smbus_write_byte_data(client, regl, data->value & 0xff); \
up(&data->update_lock); \
return count; \
}
set_temp1(temp_low1, LM90_REG_W_LOCAL_LOW);
set_temp2(temp_low2, LM90_REG_W_REMOTE_LOWH, LM90_REG_W_REMOTE_LOWL);
set_temp1(temp_high1, LM90_REG_W_LOCAL_HIGH);
set_temp2(temp_high2, LM90_REG_W_REMOTE_HIGHH, LM90_REG_W_REMOTE_HIGHL);
set_temp1(temp_crit1, LM90_REG_W_LOCAL_CRIT);
set_temp1(temp_crit2, LM90_REG_W_REMOTE_CRIT);
#define show_temp_hyst(value, basereg) \
static ssize_t show_##value(struct device *dev, char *buf) \
{ \
struct lm90_data *data = lm90_update_device(dev); \
return sprintf(buf, "%d\n", TEMP1_FROM_REG(data->basereg) \
- TEMP1_FROM_REG(data->temp_hyst)); \
}
show_temp_hyst(temp_hyst1, temp_crit1);
show_temp_hyst(temp_hyst2, temp_crit2);
static ssize_t set_temp_hyst1(struct device *dev, const char *buf,
size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct lm90_data *data = i2c_get_clientdata(client);
long val = simple_strtol(buf, NULL, 10);
long hyst;
down(&data->update_lock);
hyst = TEMP1_FROM_REG(data->temp_crit1) - val;
i2c_smbus_write_byte_data(client, LM90_REG_W_TCRIT_HYST,
HYST_TO_REG(hyst));
up(&data->update_lock);
return count;
}
static ssize_t show_alarms(struct device *dev, char *buf)
{
struct lm90_data *data = lm90_update_device(dev);
return sprintf(buf, "%d\n", data->alarms);
}
static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
static DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input2, NULL);
static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp_low1,
set_temp_low1);
static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_low2,
set_temp_low2);
static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_high1,
set_temp_high1);
static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_high2,
set_temp_high2);
static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp_crit1,
set_temp_crit1);
static DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit2,
set_temp_crit2);
static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_temp_hyst1,
set_temp_hyst1);
static DEVICE_ATTR(temp2_crit_hyst, S_IRUGO, show_temp_hyst2, NULL);
static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
/*
* Real code
*/
static int lm90_attach_adapter(struct i2c_adapter *adapter)
{
if (!(adapter->class & I2C_CLASS_HWMON))
return 0;
return i2c_detect(adapter, &addr_data, lm90_detect);
}
/*
* The following function does more than just detection. If detection
* succeeds, it also registers the new chip.
*/
static int lm90_detect(struct i2c_adapter *adapter, int address, int kind)
{
struct i2c_client *new_client;
struct lm90_data *data;
int err = 0;
const char *name = "";
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
goto exit;
if (!(data = kmalloc(sizeof(struct lm90_data), GFP_KERNEL))) {
err = -ENOMEM;
goto exit;
}
memset(data, 0, sizeof(struct lm90_data));
/* The common I2C client data is placed right before the
LM90-specific data. */
new_client = &data->client;
i2c_set_clientdata(new_client, data);
new_client->addr = address;
new_client->adapter = adapter;
new_client->driver = &lm90_driver;
new_client->flags = 0;
/*
* Now we do the remaining detection. A negative kind means that
* the driver was loaded with no force parameter (default), so we
* must both detect and identify the chip. A zero kind means that
* the driver was loaded with the force parameter, the detection
* step shall be skipped. A positive kind means that the driver
* was loaded with the force parameter and a given kind of chip is
* requested, so both the detection and the identification steps
* are skipped.
*/
/* Default to an LM90 if forced */
if (kind == 0)
kind = lm90;
if (kind < 0) { /* detection and identification */
u8 man_id, chip_id, reg_config1, reg_convrate;
man_id = i2c_smbus_read_byte_data(new_client,
LM90_REG_R_MAN_ID);
chip_id = i2c_smbus_read_byte_data(new_client,
LM90_REG_R_CHIP_ID);
reg_config1 = i2c_smbus_read_byte_data(new_client,
LM90_REG_R_CONFIG1);
reg_convrate = i2c_smbus_read_byte_data(new_client,
LM90_REG_R_CONVRATE);
if (man_id == 0x01) { /* National Semiconductor */
u8 reg_config2;
reg_config2 = i2c_smbus_read_byte_data(new_client,
LM90_REG_R_CONFIG2);
if ((reg_config1 & 0x2A) == 0x00
&& (reg_config2 & 0xF8) == 0x00
&& reg_convrate <= 0x09) {
if (address == 0x4C
&& (chip_id & 0xF0) == 0x20) { /* LM90 */
kind = lm90;
} else
if ((chip_id & 0xF0) == 0x30) { /* LM89/LM99 */
kind = lm99;
} else
if (address == 0x4C
&& (chip_id & 0xF0) == 0x10) { /* LM86 */
kind = lm86;
}
}
} else
if (man_id == 0x41) { /* Analog Devices */
if (address == 0x4C
&& (chip_id & 0xF0) == 0x40 /* ADM1032 */
&& (reg_config1 & 0x3F) == 0x00
&& reg_convrate <= 0x0A) {
kind = adm1032;
} else
if (address == 0x4c
&& chip_id == 0x51 /* ADT7461 */
&& (reg_config1 & 0x1F) == 0x00 /* check compat mode */
&& reg_convrate <= 0x0A) {
kind = adt7461;
}
} else
if (man_id == 0x4D) { /* Maxim */
/*
* The Maxim variants do NOT have a chip_id register.
* Reading from that address will return the last read
* value, which in our case is those of the man_id
* register. Likewise, the config1 register seems to
* lack a low nibble, so the value will be those of the
* previous read, so in our case those of the man_id
* register.
*/
if (chip_id == man_id
&& (reg_config1 & 0x1F) == (man_id & 0x0F)
&& reg_convrate <= 0x09) {
kind = max6657;
}
}
if (kind <= 0) { /* identification failed */
dev_info(&adapter->dev,
"Unsupported chip (man_id=0x%02X, "
"chip_id=0x%02X).\n", man_id, chip_id);
goto exit_free;
}
}
if (kind == lm90) {
name = "lm90";
} else if (kind == adm1032) {
name = "adm1032";
} else if (kind == lm99) {
name = "lm99";
} else if (kind == lm86) {
name = "lm86";
} else if (kind == max6657) {
name = "max6657";
} else if (kind == adt7461) {
name = "adt7461";
}
/* We can fill in the remaining client fields */
strlcpy(new_client->name, name, I2C_NAME_SIZE);
data->valid = 0;
data->kind = kind;
init_MUTEX(&data->update_lock);
/* Tell the I2C layer a new client has arrived */
if ((err = i2c_attach_client(new_client)))
goto exit_free;
/* Initialize the LM90 chip */
lm90_init_client(new_client);
/* Register sysfs hooks */
device_create_file(&new_client->dev, &dev_attr_temp1_input);
device_create_file(&new_client->dev, &dev_attr_temp2_input);
device_create_file(&new_client->dev, &dev_attr_temp1_min);
device_create_file(&new_client->dev, &dev_attr_temp2_min);
device_create_file(&new_client->dev, &dev_attr_temp1_max);
device_create_file(&new_client->dev, &dev_attr_temp2_max);
device_create_file(&new_client->dev, &dev_attr_temp1_crit);
device_create_file(&new_client->dev, &dev_attr_temp2_crit);
device_create_file(&new_client->dev, &dev_attr_temp1_crit_hyst);
device_create_file(&new_client->dev, &dev_attr_temp2_crit_hyst);
device_create_file(&new_client->dev, &dev_attr_alarms);
return 0;
exit_free:
kfree(data);
exit:
return err;
}
static void lm90_init_client(struct i2c_client *client)
{
u8 config;
/*
* Start the conversions.
*/
i2c_smbus_write_byte_data(client, LM90_REG_W_CONVRATE,
5); /* 2 Hz */
config = i2c_smbus_read_byte_data(client, LM90_REG_R_CONFIG1);
if (config & 0x40)
i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1,
config & 0xBF); /* run */
}
static int lm90_detach_client(struct i2c_client *client)
{
int err;
if ((err = i2c_detach_client(client))) {
dev_err(&client->dev, "Client deregistration failed, "
"client not detached.\n");
return err;
}
kfree(i2c_get_clientdata(client));
return 0;
}
static struct lm90_data *lm90_update_device(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct lm90_data *data = i2c_get_clientdata(client);
down(&data->update_lock);
if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
u8 oldh, newh;
dev_dbg(&client->dev, "Updating lm90 data.\n");
data->temp_input1 = i2c_smbus_read_byte_data(client,
LM90_REG_R_LOCAL_TEMP);
data->temp_high1 = i2c_smbus_read_byte_data(client,
LM90_REG_R_LOCAL_HIGH);
data->temp_low1 = i2c_smbus_read_byte_data(client,
LM90_REG_R_LOCAL_LOW);
data->temp_crit1 = i2c_smbus_read_byte_data(client,
LM90_REG_R_LOCAL_CRIT);
data->temp_crit2 = i2c_smbus_read_byte_data(client,
LM90_REG_R_REMOTE_CRIT);
data->temp_hyst = i2c_smbus_read_byte_data(client,
LM90_REG_R_TCRIT_HYST);
/*
* There is a trick here. We have to read two registers to
* have the remote sensor temperature, but we have to beware
* a conversion could occur inbetween the readings. The
* datasheet says we should either use the one-shot
* conversion register, which we don't want to do (disables
* hardware monitoring) or monitor the busy bit, which is
* impossible (we can't read the values and monitor that bit
* at the exact same time). So the solution used here is to
* read the high byte once, then the low byte, then the high
* byte again. If the new high byte matches the old one,
* then we have a valid reading. Else we have to read the low
* byte again, and now we believe we have a correct reading.
*/
oldh = i2c_smbus_read_byte_data(client,
LM90_REG_R_REMOTE_TEMPH);
data->temp_input2 = i2c_smbus_read_byte_data(client,
LM90_REG_R_REMOTE_TEMPL);
newh = i2c_smbus_read_byte_data(client,
LM90_REG_R_REMOTE_TEMPH);
if (newh != oldh) {
data->temp_input2 = i2c_smbus_read_byte_data(client,
LM90_REG_R_REMOTE_TEMPL);
#ifdef DEBUG
oldh = i2c_smbus_read_byte_data(client,
LM90_REG_R_REMOTE_TEMPH);
/* oldh is actually newer */
if (newh != oldh)
dev_warn(&client->dev, "Remote temperature may be "
"wrong.\n");
#endif
}
data->temp_input2 |= (newh << 8);
data->temp_high2 = (i2c_smbus_read_byte_data(client,
LM90_REG_R_REMOTE_HIGHH) << 8) +
i2c_smbus_read_byte_data(client,
LM90_REG_R_REMOTE_HIGHL);
data->temp_low2 = (i2c_smbus_read_byte_data(client,
LM90_REG_R_REMOTE_LOWH) << 8) +
i2c_smbus_read_byte_data(client,
LM90_REG_R_REMOTE_LOWL);
data->alarms = i2c_smbus_read_byte_data(client,
LM90_REG_R_STATUS);
data->last_updated = jiffies;
data->valid = 1;
}
up(&data->update_lock);
return data;
}
static int __init sensors_lm90_init(void)
{
return i2c_add_driver(&lm90_driver);
}
static void __exit sensors_lm90_exit(void)
{
i2c_del_driver(&lm90_driver);
}
MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
MODULE_DESCRIPTION("LM90/ADM1032 driver");
MODULE_LICENSE("GPL");
module_init(sensors_lm90_init);
module_exit(sensors_lm90_exit);
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