smsc47m1.c

h内核

/*
    smsc47m1.c - Part of lm_sensors, Linux kernel modules
                 for hardware monitoring

    Supports the SMSC LPC47B27x, LPC47M10x, LPC47M13x and LPC47M14x
    Super-I/O chips.

    Copyright (C) 2002 Mark D. Studebaker <[e-mail]>
    Copyright (C) 2004 Jean Delvare <[e-mail]>
    Ported to Linux 2.6 by Gabriele Gorla <[e-mail]>
                        and Jean Delvare

    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/ioport.h>
#include <linux/i2c.h>
#include <linux/i2c-sensor.h>
#include <linux/init.h>
#include <asm/io.h>

static unsigned short normal_i2c[] = { I2C_CLIENT_END };
/* Address is autodetected, there is no default value */
static unsigned int normal_isa[] = { 0x0000, I2C_CLIENT_ISA_END };
static struct i2c_force_data forces[] = {{NULL}};

enum chips { any_chip, smsc47m1 };
static struct i2c_address_data addr_data = {
	.normal_i2c		= normal_i2c,
	.normal_isa		= normal_isa,
	.forces			= forces,
};

/* Super-I/0 registers and commands */

#define	REG	0x2e	/* The register to read/write */
#define	VAL	0x2f	/* The value to read/write */

static inline void
superio_outb(int reg, int val)
{
	outb(reg, REG);
	outb(val, VAL);
}

static inline int
superio_inb(int reg)
{
	outb(reg, REG);
	return inb(VAL);
}

/* logical device for fans is 0x0A */
#define superio_select() superio_outb(0x07, 0x0A)

static inline void
superio_enter(void)
{
	outb(0x55, REG);
}

static inline void
superio_exit(void)
{
	outb(0xAA, REG);
}

#define SUPERIO_REG_ACT		0x30
#define SUPERIO_REG_BASE	0x60
#define SUPERIO_REG_DEVID	0x20

/* Logical device registers */

#define SMSC_EXTENT		0x80

/* nr is 0 or 1 in the macros below */
#define SMSC47M1_REG_ALARM		0x04
#define SMSC47M1_REG_TPIN(nr)		(0x34 - (nr))
#define SMSC47M1_REG_PPIN(nr)		(0x36 - (nr))
#define SMSC47M1_REG_PWM(nr)		(0x56 + (nr))
#define SMSC47M1_REG_FANDIV		0x58
#define SMSC47M1_REG_FAN(nr)		(0x59 + (nr))
#define SMSC47M1_REG_FAN_PRELOAD(nr)	(0x5B + (nr))

#define MIN_FROM_REG(reg,div)		((reg)>=192 ? 0 : \
					 983040/((192-(reg))*(div)))
#define FAN_FROM_REG(reg,div,preload)	((reg)<=(preload) || (reg)==255 ? 0 : \
					 983040/(((reg)-(preload))*(div)))
#define DIV_FROM_REG(reg)		(1 << (reg))
#define PWM_FROM_REG(reg)		(((reg) & 0x7E) << 1)
#define PWM_EN_FROM_REG(reg)		((~(reg)) & 0x01)
#define PWM_TO_REG(reg)			(((reg) >> 1) & 0x7E)

struct smsc47m1_data {
	struct i2c_client client;
	struct semaphore lock;
	int sysctl_id;

	struct semaphore update_lock;
	unsigned long last_updated;	/* In jiffies */

	u8 fan[2];		/* Register value */
	u8 fan_preload[2];	/* Register value */
	u8 fan_div[2];		/* Register encoding, shifted right */
	u8 alarms;		/* Register encoding */
	u8 pwm[2];		/* Register value (bit 7 is enable) */
};


static int smsc47m1_attach_adapter(struct i2c_adapter *adapter);
static int smsc47m1_find(int *address);
static int smsc47m1_detect(struct i2c_adapter *adapter, int address, int kind);
static int smsc47m1_detach_client(struct i2c_client *client);

static int smsc47m1_read_value(struct i2c_client *client, u8 reg);
static void smsc47m1_write_value(struct i2c_client *client, u8 reg, u8 value);

static struct smsc47m1_data *smsc47m1_update_device(struct device *dev,
		int init);


static int smsc47m1_id;

static struct i2c_driver smsc47m1_driver = {
	.owner		= THIS_MODULE,
	.name		= "smsc47m1",
	.id		= I2C_DRIVERID_SMSC47M1,
	.flags		= I2C_DF_NOTIFY,
	.attach_adapter	= smsc47m1_attach_adapter,
	.detach_client	= smsc47m1_detach_client,
};

/* nr is 0 or 1 in the callback functions below */

static ssize_t get_fan(struct device *dev, char *buf, int nr)
{
	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
	/* This chip (stupidly) stops monitoring fan speed if PWM is
	   enabled and duty cycle is 0%. This is fine if the monitoring
	   and control concern the same fan, but troublesome if they are
	   not (which could as well happen). */
	int rpm = (data->pwm[nr] & 0x7F) == 0x00 ? 0 :
		  FAN_FROM_REG(data->fan[nr],
			       DIV_FROM_REG(data->fan_div[nr]),
			       data->fan_preload[nr]);
	return sprintf(buf, "%d\n", rpm);
}

static ssize_t get_fan_min(struct device *dev, char *buf, int nr)
{
	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
	int rpm = MIN_FROM_REG(data->fan_preload[nr],
			       DIV_FROM_REG(data->fan_div[nr]));
	return sprintf(buf, "%d\n", rpm);
}

static ssize_t get_fan_div(struct device *dev, char *buf, int nr)
{
	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[nr]));
}

static ssize_t get_pwm(struct device *dev, char *buf, int nr)
{
	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
	return sprintf(buf, "%d\n", PWM_FROM_REG(data->pwm[nr]));
}

static ssize_t get_pwm_en(struct device *dev, char *buf, int nr)
{
	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
	return sprintf(buf, "%d\n", PWM_EN_FROM_REG(data->pwm[nr]));
}

static ssize_t get_alarms(struct device *dev, char *buf)
{
	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
	return sprintf(buf, "%d\n", data->alarms);
}

static ssize_t set_fan_min(struct device *dev, const char *buf,
		size_t count, int nr)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct smsc47m1_data *data = i2c_get_clientdata(client);

	long rpmdiv = simple_strtol(buf, NULL, 10)
		    * DIV_FROM_REG(data->fan_div[nr]);

	if (983040 > 192 * rpmdiv || 2 * rpmdiv > 983040)
		return -EINVAL;

	data->fan_preload[nr] = 192 - ((983040 + rpmdiv / 2) / rpmdiv);
	smsc47m1_write_value(client, SMSC47M1_REG_FAN_PRELOAD(nr),
			     data->fan_preload[nr]);

	return count;
}

/* Note: we save and restore the fan minimum here, because its value is
   determined in part by the fan clock divider.  This follows the principle
   of least suprise; the user doesn't expect the fan minimum to change just
   because the divider changed. */
static ssize_t set_fan_div(struct device *dev, const char *buf,
		size_t count, int nr)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct smsc47m1_data *data = i2c_get_clientdata(client);

	long new_div = simple_strtol(buf, NULL, 10), tmp;
	u8 old_div = DIV_FROM_REG(data->fan_div[nr]);

	if (new_div == old_div) /* No change */
		return count;
	switch (new_div) {
	case 1: data->fan_div[nr] = 0; break;
	case 2: data->fan_div[nr] = 1; break;
	case 4: data->fan_div[nr] = 2; break;
	case 8: data->fan_div[nr] = 3; break;
	default: return -EINVAL;
	}

	tmp = smsc47m1_read_value(client, SMSC47M1_REG_FANDIV) & 0x0F;
	tmp |= (data->fan_div[0] << 4) | (data->fan_div[1] << 6);
	smsc47m1_write_value(client, SMSC47M1_REG_FANDIV, tmp);

	/* Preserve fan min */
	tmp = 192 - (old_div * (192 - data->fan_preload[nr])
		     + new_div / 2) / new_div;
	data->fan_preload[nr] = SENSORS_LIMIT(tmp, 0, 191);
	smsc47m1_write_value(client, SMSC47M1_REG_FAN_PRELOAD(nr),
			     data->fan_preload[nr]);

	return count;
}

static ssize_t set_pwm(struct device *dev, const char *buf,
		size_t count, int nr)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct smsc47m1_data *data = i2c_get_clientdata(client);

	long val = simple_strtol(buf, NULL, 10);

	if (val < 0 || val > 255)
		return -EINVAL;

	data->pwm[nr] &= 0x81; /* Preserve additional bits */
	data->pwm[nr] |= PWM_TO_REG(val);

	smsc47m1_write_value(client, SMSC47M1_REG_PWM(nr),
			     data->pwm[nr]);
	return count;
}

static ssize_t set_pwm_en(struct device *dev, const char *buf,
		size_t count, int nr)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct smsc47m1_data *data = i2c_get_clientdata(client);

	long val = simple_strtol(buf, NULL, 10);
	
	if (val != 0 && val != 1)
		return -EINVAL;

	data->pwm[nr] &= 0xFE; /* preserve the other bits */
	data->pwm[nr] |= !val;

	smsc47m1_write_value(client, SMSC47M1_REG_PWM(nr),
			     data->pwm[nr]);

	return count;
}

#define fan_present(offset)						\
static ssize_t get_fan##offset (struct device *dev, char *buf)		\
{									\
	return get_fan(dev, buf, offset - 1);				\