root/lm-sensors/trunk/kernel/chips/lm83.c @ 2192

/*
 * lm83.c - Part of lm_sensors, Linux kernel modules for hardware
 *          monitoring
 * Copyright (C) 2003  Jean Delvare <khali@linux-fr.org>
 *
 * Heavily inspired from the lm78, lm75 and adm1021 drivers. The LM83 is
 * a sensor chip made by National Semiconductor. It reports up to four
 * temperatures (its own plus up to three external ones) with a 1 deg
 * resolution and a 3-4 deg accuracy. Complete datasheet can be obtained
 * from National's website at:
 *   http://www.national.com/pf/LM/LM83.html
 * Since the datasheet omits to give the chip stepping code, I give it
 * here: 0x03 (at register 0xff).
 *
 * 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/slab.h>
#include <linux/i2c.h>
#include <linux/i2c-proc.h>
#include <linux/init.h>
#include "version.h"

/*
 * Addresses to scan
 * Address is selected using 2 three-level pins, resulting in 9 possible
 * addresses.
 */

static unsigned short normal_i2c[] = { SENSORS_I2C_END };
static unsigned short normal_i2c_range[] = { 0x18, 0x1a, 0x29, 0x2b,
        0x4c, 0x4e, SENSORS_I2C_END };
static unsigned int normal_isa[] = { SENSORS_ISA_END };
static unsigned int normal_isa_range[] = { SENSORS_ISA_END };

/*
 * Insmod parameters
 */

SENSORS_INSMOD_1(lm83);

/*
 * The LM83 registers
 * Manufacturer ID is 0x01 for National Semiconductor.
 */

#define LM83_REG_R_MAN_ID        0xFE
#define LM83_REG_R_CHIP_ID       0xFF
#define LM83_REG_R_CONFIG        0x03
#define LM83_REG_W_CONFIG        0x09
#define LM83_REG_R_STATUS1       0x02
#define LM83_REG_R_STATUS2       0x35
#define LM83_REG_R_LOCAL_TEMP    0x00
#define LM83_REG_R_LOCAL_HIGH    0x05
#define LM83_REG_W_LOCAL_HIGH    0x0B
#define LM83_REG_R_REMOTE1_TEMP  0x30
#define LM83_REG_R_REMOTE1_HIGH  0x38
#define LM83_REG_W_REMOTE1_HIGH  0x50
#define LM83_REG_R_REMOTE2_TEMP  0x01
#define LM83_REG_R_REMOTE2_HIGH  0x07
#define LM83_REG_W_REMOTE2_HIGH  0x0D
#define LM83_REG_R_REMOTE3_TEMP  0x31
#define LM83_REG_R_REMOTE3_HIGH  0x3A
#define LM83_REG_W_REMOTE3_HIGH  0x52
#define LM83_REG_R_TCRIT         0x42
#define LM83_REG_W_TCRIT         0x5A

/*
 * Conversions and various macros
 * The LM83 uses signed 8-bit values.
 */

#define TEMP_FROM_REG(val)  (val > 127 ? val-256 : val)
#define TEMP_TO_REG(val)    (val < 0 ? val+256 : val)

static const u8 LM83_REG_R_TEMP[] = {
        LM83_REG_R_LOCAL_TEMP,
        LM83_REG_R_REMOTE1_TEMP,
        LM83_REG_R_REMOTE2_TEMP,
        LM83_REG_R_REMOTE3_TEMP
};

static const u8 LM83_REG_R_HIGH[] = {
        LM83_REG_R_LOCAL_HIGH,
        LM83_REG_R_REMOTE1_HIGH,
        LM83_REG_R_REMOTE2_HIGH,
        LM83_REG_R_REMOTE3_HIGH
};

static const u8 LM83_REG_W_HIGH[] = {
        LM83_REG_W_LOCAL_HIGH,
        LM83_REG_W_REMOTE1_HIGH,
        LM83_REG_W_REMOTE2_HIGH,
        LM83_REG_W_REMOTE3_HIGH
};

/*
 * Functions declaration
 */

static int lm83_attach_adapter(struct i2c_adapter *adapter);
static int lm83_detect(struct i2c_adapter *adapter, int address, unsigned
        short flags, int kind);
static int lm83_detach_client(struct i2c_client *client);
static void lm83_update_client(struct i2c_client *client);
static void lm83_temp(struct i2c_client *client, int operation, int
        ctl_name, int *nrels_mag, long *results);
static void lm83_tcrit(struct i2c_client *client, int operation, int
        ctl_name, int *nrels_mag, long *results);
static void lm83_alarms(struct i2c_client *client, int operation, int
        ctl_name, int *nrels_mag, long *results);

/*
 * Driver data (common to all clients)
 */
 
static struct i2c_driver lm83_driver = {
        .owner          = THIS_MODULE,
        .name           = "LM83 sensor driver",
        .id             = I2C_DRIVERID_LM83,
        .flags          = I2C_DF_NOTIFY,
        .attach_adapter = lm83_attach_adapter,
        .detach_client  = lm83_detach_client,
};

/*
 * Client data (each client gets its own)
 */

struct lm83_data
{
        int sysctl_id;

        struct semaphore update_lock;
        char valid; /* zero until following fields are valid */
        unsigned long last_updated; /* in jiffies */

        /* registers values */
        u8 temp[4], temp_high[4], tcrit;
        u16 alarms; /* bitvector, combined */
};

/*
 * Proc entries
 * These files are created for each detected LM83.
 */

/* -- SENSORS SYSCTL START -- */

#define LM83_SYSCTL_LOCAL_TEMP    1200
#define LM83_SYSCTL_REMOTE1_TEMP  1201
#define LM83_SYSCTL_REMOTE2_TEMP  1202
#define LM83_SYSCTL_REMOTE3_TEMP  1203
#define LM83_SYSCTL_TCRIT         1208
#define LM83_SYSCTL_ALARMS        1210

#define LM83_ALARM_LOCAL_HIGH     0x0040
#define LM83_ALARM_LOCAL_CRIT     0x0001
#define LM83_ALARM_REMOTE1_HIGH   0x8000
#define LM83_ALARM_REMOTE1_CRIT   0x0100
#define LM83_ALARM_REMOTE1_OPEN   0x2000
#define LM83_ALARM_REMOTE2_HIGH   0x0010
#define LM83_ALARM_REMOTE2_CRIT   0x0002
#define LM83_ALARM_REMOTE2_OPEN   0x0004
#define LM83_ALARM_REMOTE3_HIGH   0x1000
#define LM83_ALARM_REMOTE3_CRIT   0x0200
#define LM83_ALARM_REMOTE3_OPEN   0x0400

/* -- SENSORS SYSCTL END -- */


static ctl_table lm83_dir_table_template[] =
{
        {LM83_SYSCTL_LOCAL_TEMP, "temp1", NULL, 0, 0644, NULL,
         &i2c_proc_real, &i2c_sysctl_real, NULL, &lm83_temp},
        {LM83_SYSCTL_REMOTE1_TEMP, "temp2", NULL, 0, 0644, NULL,
         &i2c_proc_real, &i2c_sysctl_real, NULL, &lm83_temp},
        {LM83_SYSCTL_REMOTE2_TEMP, "temp3", NULL, 0, 0644, NULL,
         &i2c_proc_real, &i2c_sysctl_real, NULL, &lm83_temp},
        {LM83_SYSCTL_REMOTE3_TEMP, "temp4", NULL, 0, 0644, NULL,
         &i2c_proc_real, &i2c_sysctl_real, NULL, &lm83_temp},
        {LM83_SYSCTL_TCRIT, "tcrit", NULL, 0, 0644, NULL,
         &i2c_proc_real, &i2c_sysctl_real, NULL, &lm83_tcrit},
        {LM83_SYSCTL_ALARMS, "alarms", NULL, 0, 0444, NULL,
         &i2c_proc_real, &i2c_sysctl_real, NULL, &lm83_alarms},
        {0}
};

/*
 * Internal variables
 */

static int lm83_id = 0;

/*
 * Real code
 */

static int lm83_attach_adapter(struct i2c_adapter *adapter)
{
        return i2c_detect(adapter, &addr_data, lm83_detect);
}

/*
 * The following function does more than just detection. If detection
 * succeeds, it also registers the new chip.
 */
static int lm83_detect(struct i2c_adapter *adapter, int address, unsigned
        short flags, int kind)
{
        struct i2c_client *new_client;
        struct lm83_data *data;
        int err = 0;
        const char *type_name = "";
        const char *client_name = "";

#ifdef DEBUG
        if (i2c_is_isa_adapter(adapter))
        {
                printk("lm83.o: Called for an ISA bus adapter, aborting.\n");
                return 0;
        }
#endif

        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
        {
#ifdef DEBUG
                printk("lm83.o: I2C bus doesn't support byte read mode, "
                       "skipping.\n");
#endif
                return 0;
        }

        if (!(new_client = kmalloc(sizeof(struct i2c_client) + sizeof(struct
                lm83_data), GFP_KERNEL)))
        {
                printk("lm83.o: Out of memory in lm83_detect (new_client).\n");
                return -ENOMEM;
        }

        /*
         * The LM83-specific data is placed right after the common I2C
         * client data, and is pointed to by the data field from the I2C
         * client data.
         */

        new_client->addr = address;
        new_client->data = data = (struct lm83_data *) (new_client + 1);
        new_client->adapter = adapter;
        new_client->driver = &lm83_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 (actually there is only
         * one possible kind of chip for now, LM83). 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.
         */

        if (kind < 0) /* detection */
        {
                if (((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1)
                      & 0xA8) != 0x00)
                ||  ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2)
                      & 0x48) != 0x00)
                ||  ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG)
                      & 0x41) != 0x00))
                {
#ifdef DEBUG
                        printk(KERN_DEBUG "lm83.o: Detection failed at 0x%02x.\n",
                                address);
#endif
                        goto ERROR1;
                }
        }

        if (kind <= 0) /* identification */
        {
                u8 man_id, chip_id;

                man_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_MAN_ID);
                chip_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_CHIP_ID);
                if (man_id == 0x01) /* National Semiconductor */
                {
                        if (chip_id == 0x03)
                                kind = lm83;
                }
        }

        if (kind <= 0) /* identification failed */
        {
                printk("lm83.o: Unsupported chip.\n");
                goto ERROR1;
        }

        if (kind == lm83)
        {
                type_name = "lm83";
                client_name = "LM83 chip";
        }
        else
        {
                printk("lm83.o: Unknown kind %d.\n", kind);
                goto ERROR1;
        }
        
        /*
         * OK, we got a valid chip so we can fill in the remaining client
         * fields.
         */

        strcpy(new_client->name, client_name);
        new_client->id = lm83_id++;
        data->valid = 0;
        init_MUTEX(&data->update_lock);

        /*
         * Tell the I2C layer a new client has arrived.
         */

        if ((err = i2c_attach_client(new_client)))
        {
#ifdef DEBUG
                printk("lm83.o: Failed attaching client.\n");
#endif
                goto ERROR1;
        }

        /*
         * Register a new directory entry.
         */

        if ((err = i2c_register_entry(new_client, type_name,
             lm83_dir_table_template)) < 0)
        {
#ifdef DEBUG
                printk("lm83.o: Failed registering directory entry.\n");
#endif
                goto ERROR2;
        }
        data->sysctl_id = err;

        /*
         * Initialize the LM83 chip
         * (Nothing to do for this one.)
         */

        return 0;

        ERROR2:
        i2c_detach_client(new_client);
        ERROR1:
        kfree(new_client);
        return err;
}

static int lm83_detach_client(struct i2c_client *client)
{
        int err;

        i2c_deregister_entry(((struct lm83_data *) (client->data))->sysctl_id);
        if ((err = i2c_detach_client(client)))
        {
                printk("lm83.o: Client deregistration failed, client not "
                       "detached.\n");
                return err;
        }

        kfree(client);
        return 0;
}

static void lm83_update_client(struct i2c_client *client)
{
        struct lm83_data *data = client->data;

        down(&data->update_lock);

        if ((jiffies - data->last_updated > HZ * 2) ||
            (jiffies < data->last_updated) || !data->valid)
        {
                int nr;
#ifdef DEBUG
                printk("lm83.o: Updating LM83 data.\n");
#endif
                for (nr = 0; nr < 4 ; nr++)
                {
                        data->temp[nr] =
                                i2c_smbus_read_byte_data(client, LM83_REG_R_TEMP[nr]);
                        data->temp_high[nr] =
                                i2c_smbus_read_byte_data(client, LM83_REG_R_HIGH[nr]);
                }
                data->tcrit = i2c_smbus_read_byte_data(client, LM83_REG_R_TCRIT);
                data->alarms =
                        i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1) +
                        (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2) << 8);

                data->last_updated = jiffies;
                data->valid = 1;
        }

        up(&data->update_lock);
}

static void lm83_temp(struct i2c_client *client, int operation, int
        ctl_name, int *nrels_mag, long *results)
{
        struct lm83_data *data = client->data;
        int nr = ctl_name - LM83_SYSCTL_LOCAL_TEMP;

        if (operation == SENSORS_PROC_REAL_INFO)
                *nrels_mag = 0; /* magnitude */
        else if (operation == SENSORS_PROC_REAL_READ)
        {
                lm83_update_client(client);
                results[0] = TEMP_FROM_REG(data->temp_high[nr]);
                results[1] = TEMP_FROM_REG(data->temp[nr]);
                *nrels_mag = 2;
        }
        else if (operation == SENSORS_PROC_REAL_WRITE)
        {
                if (*nrels_mag >= 1)
                {
                        data->temp_high[nr] = TEMP_TO_REG(results[0]);
                        i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr],
                                            data->temp_high[nr]);
                }
        }
}

static void lm83_tcrit(struct i2c_client *client, int operation, int
        ctl_name, int *nrels_mag, long *results)
{
        struct lm83_data *data = client->data;

        if (operation == SENSORS_PROC_REAL_INFO)
                *nrels_mag = 0; /* magnitude */
        else if (operation == SENSORS_PROC_REAL_READ)
        {
                lm83_update_client(client);
                results[0] = TEMP_FROM_REG(data->tcrit);
                *nrels_mag = 1;
        }
        else if (operation == SENSORS_PROC_REAL_WRITE)
        {
                if (*nrels_mag >= 1)
                {
                        data->tcrit = TEMP_TO_REG(results[0]);
                        i2c_smbus_write_byte_data(client, LM83_REG_W_TCRIT,
                                data->tcrit);
                }
        }
}

static void lm83_alarms(struct i2c_client *client, int operation, int
        ctl_name, int *nrels_mag, long *results)
{
        struct lm83_data *data = client->data;

        if (operation == SENSORS_PROC_REAL_INFO)
                *nrels_mag = 0; /* magnitude */
        else if (operation == SENSORS_PROC_REAL_READ)
        {
                lm83_update_client(client);
                results[0] = data->alarms;
                *nrels_mag = 1;
        }
}

static int __init sm_lm83_init(void)
{
        printk(KERN_INFO "lm83.o version %s (%s)\n", LM_VERSION, LM_DATE);
        return i2c_add_driver(&lm83_driver);
}

static void __exit sm_lm83_exit(void)
{
        i2c_del_driver(&lm83_driver);
}

MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
MODULE_DESCRIPTION("LM83 sensor driver");
MODULE_LICENSE("GPL");

module_init(sm_lm83_init);
module_exit(sm_lm83_exit);