it87.c

ite_8075 io source code temperature and fan speed control for linux

		     &dev_attr_pwm2_freq))
		 || (err = device_create_file(dev,
		     &dev_attr_pwm3_freq)))
			goto ERROR4;
	}

	if (data->type == it8712 || data->type == it8716
	 || data->type == it8718) {
		data->vrm = vid_which_vrm();
		/* VID reading from Super-I/O config space if available */
		data->vid = sio_data->vid_value;
		if ((err = device_create_file(dev,
		     &dev_attr_vrm))
		 || (err = device_create_file(dev,
		     &dev_attr_cpu0_vid)))
			goto ERROR4;
	}

	data->hwmon_dev = hwmon_device_register(dev);
	if (IS_ERR(data->hwmon_dev)) {
		err = PTR_ERR(data->hwmon_dev);
		goto ERROR4;
	}

	return 0;

ERROR4:
	sysfs_remove_group(&dev->kobj, &it87_group);
	sysfs_remove_group(&dev->kobj, &it87_group_opt);
ERROR2:
	platform_set_drvdata(pdev, NULL);
	kfree(data);
ERROR1:
	release_region(res->start, IT87_EC_EXTENT);
ERROR0:
	return err;
}

static int __devexit it87_remove(struct platform_device *pdev)
{
	struct it87_data *data = platform_get_drvdata(pdev);

	hwmon_device_unregister(data->hwmon_dev);
	sysfs_remove_group(&pdev->dev.kobj, &it87_group);
	sysfs_remove_group(&pdev->dev.kobj, &it87_group_opt);

	release_region(data->addr, IT87_EC_EXTENT);
	platform_set_drvdata(pdev, NULL);
	kfree(data);

	return 0;
}

/* Must be called with data->update_lock held, except during initialization.
   We ignore the IT87 BUSY flag at this moment - it could lead to deadlocks,
   would slow down the IT87 access and should not be necessary. */
static int it87_read_value(struct it87_data *data, u8 reg)
{
	outb_p(reg, data->addr + IT87_ADDR_REG_OFFSET);
	return inb_p(data->addr + IT87_DATA_REG_OFFSET);
}

/* Must be called with data->update_lock held, except during initialization.
   We ignore the IT87 BUSY flag at this moment - it could lead to deadlocks,
   would slow down the IT87 access and should not be necessary. */
static void it87_write_value(struct it87_data *data, u8 reg, u8 value)
{
	outb_p(reg, data->addr + IT87_ADDR_REG_OFFSET);
	outb_p(value, data->addr + IT87_DATA_REG_OFFSET);
}

/* Return 1 if and only if the PWM interface is safe to use */
static int __devinit it87_check_pwm(struct device *dev)
{
	struct it87_data *data = dev_get_drvdata(dev);
	/* Some BIOSes fail to correctly configure the IT87 fans. All fans off
	 * and polarity set to active low is sign that this is the case so we
	 * disable pwm control to protect the user. */
	int tmp = it87_read_value(data, IT87_REG_FAN_CTL);
	if ((tmp & 0x87) == 0) {
		if (fix_pwm_polarity) {
			/* The user asks us to attempt a chip reconfiguration.
			 * This means switching to active high polarity and
			 * inverting all fan speed values. */
			int i;
			u8 pwm[3];

			for (i = 0; i < 3; i++)
				pwm[i] = it87_read_value(data,
							 IT87_REG_PWM(i));

			/* If any fan is in automatic pwm mode, the polarity
			 * might be correct, as suspicious as it seems, so we
			 * better don't change anything (but still disable the
			 * PWM interface). */
			if (!((pwm[0] | pwm[1] | pwm[2]) & 0x80)) {
				dev_info(dev, "Reconfiguring PWM to "
					 "active high polarity\n");
				it87_write_value(data, IT87_REG_FAN_CTL,
						 tmp | 0x87);
				for (i = 0; i < 3; i++)
					it87_write_value(data,
							 IT87_REG_PWM(i),
							 0x7f & ~pwm[i]);
				return 1;
			}

			dev_info(dev, "PWM configuration is "
				 "too broken to be fixed\n");
		}

		dev_info(dev, "Detected broken BIOS "
			 "defaults, disabling PWM interface\n");
		return 0;
	} else if (fix_pwm_polarity) {
		dev_info(dev, "PWM configuration looks "
			 "sane, won't touch\n");
	}

	return 1;
}

/* Called when we have found a new IT87. */
static void __devinit it87_init_device(struct platform_device *pdev)
{
	struct it87_data *data = platform_get_drvdata(pdev);
	int tmp, i;

	/* initialize to sane defaults:
	 * - if the chip is in manual pwm mode, this will be overwritten with
	 *   the actual settings on the chip (so in this case, initialization
	 *   is not needed)
	 * - if in automatic or on/off mode, we could switch to manual mode,
	 *   read the registers and set manual_pwm_ctl accordingly, but currently
	 *   this is not implemented, so we initialize to something sane */
	for (i = 0; i < 3; i++) {
		data->manual_pwm_ctl[i] = 0xff;
	}

	/* Some chips seem to have default value 0xff for all limit
	 * registers. For low voltage limits it makes no sense and triggers
	 * alarms, so change to 0 instead. For high temperature limits, it
	 * means -1 degree C, which surprisingly doesn't trigger an alarm,
	 * but is still confusing, so change to 127 degrees C. */
	for (i = 0; i < 8; i++) {
		tmp = it87_read_value(data, IT87_REG_VIN_MIN(i));
		if (tmp == 0xff)
			it87_write_value(data, IT87_REG_VIN_MIN(i), 0);
	}
	for (i = 0; i < 3; i++) {
		tmp = it87_read_value(data, IT87_REG_TEMP_HIGH(i));
		if (tmp == 0xff)
			it87_write_value(data, IT87_REG_TEMP_HIGH(i), 127);
	}

	/* Check if temperature channnels are reset manually or by some reason */
	tmp = it87_read_value(data, IT87_REG_TEMP_ENABLE);
	if ((tmp & 0x3f) == 0) {
		/* Temp1,Temp3=thermistor; Temp2=thermal diode */
		tmp = (tmp & 0xc0) | 0x2a;
		it87_write_value(data, IT87_REG_TEMP_ENABLE, tmp);
	}
	data->sensor = tmp;

	/* Check if voltage monitors are reset manually or by some reason */
	tmp = it87_read_value(data, IT87_REG_VIN_ENABLE);
	if ((tmp & 0xff) == 0) {
		/* Enable all voltage monitors */
		it87_write_value(data, IT87_REG_VIN_ENABLE, 0xff);
	}

	/* Check if tachometers are reset manually or by some reason */
	data->fan_main_ctrl = it87_read_value(data, IT87_REG_FAN_MAIN_CTRL);
	if ((data->fan_main_ctrl & 0x70) == 0) {
		/* Enable all fan tachometers */
		data->fan_main_ctrl |= 0x70;
		it87_write_value(data, IT87_REG_FAN_MAIN_CTRL, data->fan_main_ctrl);
	}
	data->has_fan = (data->fan_main_ctrl >> 4) & 0x07;

	/* Set tachometers to 16-bit mode if needed */
	if (data->type == it8716 || data->type == it8718) {
		tmp = it87_read_value(data, IT87_REG_FAN_16BIT);
		if (~tmp & 0x07 & data->has_fan) {
			dev_dbg(&pdev->dev,
				"Setting fan1-3 to 16-bit mode\n");
			it87_write_value(data, IT87_REG_FAN_16BIT,
					 tmp | 0x07);
		}
		if (tmp & (1 << 4))
			data->has_fan |= (1 << 3);	/* fan4 enabled */
		if (tmp & (1 << 5))
			data->has_fan |= (1 << 4);	/* fan5 enabled */
	}

	/* Set current fan mode registers and the default settings for the
	 * other mode registers */
	for (i = 0; i < 3; i++) {
		if (data->fan_main_ctrl & (1 << i)) {
			/* pwm mode */
			tmp = it87_read_value(data, IT87_REG_PWM(i));
			if (tmp & 0x80) {
				/* automatic pwm - not yet implemented, but
				 * leave the settings made by the BIOS alone
				 * until a change is requested via the sysfs
				 * interface */
			} else {
				/* manual pwm */
				data->manual_pwm_ctl[i] = PWM_FROM_REG(tmp);
			}
		}
 	}

	/* Start monitoring */
	it87_write_value(data, IT87_REG_CONFIG,
			 (it87_read_value(data, IT87_REG_CONFIG) & 0x36)
			 | (update_vbat ? 0x41 : 0x01));
}

static struct it87_data *it87_update_device(struct device *dev)
{
	struct it87_data *data = dev_get_drvdata(dev);
	int i;

	mutex_lock(&data->update_lock);

	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
	    || !data->valid) {

		if (update_vbat) {
			/* Cleared after each update, so reenable.  Value
		 	  returned by this read will be previous value */	
			it87_write_value(data, IT87_REG_CONFIG,
			   it87_read_value(data, IT87_REG_CONFIG) | 0x40);
		}
		for (i = 0; i <= 7; i++) {
			data->in[i] =
			    it87_read_value(data, IT87_REG_VIN(i));
			data->in_min[i] =
			    it87_read_value(data, IT87_REG_VIN_MIN(i));
			data->in_max[i] =
			    it87_read_value(data, IT87_REG_VIN_MAX(i));
		}
		/* in8 (battery) has no limit registers */
		data->in[8] =
		    it87_read_value(data, IT87_REG_VIN(8));

		for (i = 0; i < 5; i++) {
			/* Skip disabled fans */
			if (!(data->has_fan & (1 << i)))
				continue;

			data->fan_min[i] =
			    it87_read_value(data, IT87_REG_FAN_MIN[i]);
			data->fan[i] = it87_read_value(data,
				       IT87_REG_FAN[i]);
			/* Add high byte if in 16-bit mode */
			if (data->type == it8716 || data->type == it8718) {
				data->fan[i] |= it87_read_value(data,
						IT87_REG_FANX[i]) << 8;
				data->fan_min[i] |= it87_read_value(data,
						IT87_REG_FANX_MIN[i]) << 8;
			}
		}
		for (i = 0; i < 3; i++) {
			data->temp[i] =
			    it87_read_value(data, IT87_REG_TEMP(i));
			data->temp_high[i] =
			    it87_read_value(data, IT87_REG_TEMP_HIGH(i));
			data->temp_low[i] =
			    it87_read_value(data, IT87_REG_TEMP_LOW(i));
		}

		/* Newer chips don't have clock dividers */
		if ((data->has_fan & 0x07) && data->type != it8716
		 && data->type != it8718) {
			i = it87_read_value(data, IT87_REG_FAN_DIV);
			data->fan_div[0] = i & 0x07;
			data->fan_div[1] = (i >> 3) & 0x07;
			data->fan_div[2] = (i & 0x40) ? 3 : 1;
		}

		data->alarms =
			it87_read_value(data, IT87_REG_ALARM1) |
			(it87_read_value(data, IT87_REG_ALARM2) << 8) |
			(it87_read_value(data, IT87_REG_ALARM3) << 16);
		data->fan_main_ctrl = it87_read_value(data,
				IT87_REG_FAN_MAIN_CTRL);
		data->fan_ctl = it87_read_value(data, IT87_REG_FAN_CTL);

		data->sensor = it87_read_value(data, IT87_REG_TEMP_ENABLE);
		/* The 8705 does not have VID capability */
		if (data->type == it8712 || data->type == it8716) {
			data->vid = it87_read_value(data, IT87_REG_VID);
			/* The older IT8712F revisions had only 5 VID pins,
			   but we assume it is always safe to read 6 bits. */
			data->vid &= 0x3f;
		}
		data->last_updated = jiffies;
		data->valid = 1;
	}

	mutex_unlock(&data->update_lock);

	return data;
}

static int __init it87_device_add(unsigned short address,
				  const struct it87_sio_data *sio_data)
{
	struct resource res = {
		.start	= address + IT87_EC_OFFSET,
		.end	= address + IT87_EC_OFFSET + IT87_EC_EXTENT - 1,
		.name	= DRVNAME,
		.flags	= IORESOURCE_IO,
	};
	int err;

	pdev = platform_device_alloc(DRVNAME, address);
	if (!pdev) {
		err = -ENOMEM;
		printk(KERN_ERR DRVNAME ": Device allocation failed\n");
		goto exit;
	}

	err = platform_device_add_resources(pdev, &res, 1);
	if (err) {
		printk(KERN_ERR DRVNAME ": Device resource addition failed "
		       "(%d)\n", err);
		goto exit_device_put;
	}

	err = platform_device_add_data(pdev, sio_data,
				       sizeof(struct it87_sio_data));
	if (err) {
		printk(KERN_ERR DRVNAME ": Platform data allocation failed\n");
		goto exit_device_put;
	}

	err = platform_device_add(pdev);
	if (err) {
		printk(KERN_ERR DRVNAME ": Device addition failed (%d)\n",
		       err);
		goto exit_device_put;
	}

	return 0;

exit_device_put:
	platform_device_put(pdev);
exit:
	return err;
}

static int __init sm_it87_init(void)
{
	int err;
	unsigned short isa_address=0;
	struct it87_sio_data sio_data;

	err = it87_find(&isa_address, &sio_data);
	if (err)
		return err;
	err = platform_driver_register(&it87_driver);
	if (err)
		return err;

	err = it87_device_add(isa_address, &sio_data);
	if (err){
		platform_driver_unregister(&it87_driver);
		return err;
	}

	return 0;
}

static void __exit sm_it87_exit(void)
{
	platform_device_unregister(pdev);
	platform_driver_unregister(&it87_driver);
}


MODULE_AUTHOR("Chris Gauthron, "
	      "Jean Delvare <[e-mail]>" "Cark Li <[e-mail]>");
MODULE_DESCRIPTION("IT8705F/8712F/8716F/8718F/8720F/8726F/8781F/8782F, SiS950 driver");
module_param(update_vbat, bool, 0);
MODULE_PARM_DESC(update_vbat, "Update vbat if set else return powerup value");
module_param(fix_pwm_polarity, bool, 0);
MODULE_PARM_DESC(fix_pwm_polarity, "Force PWM polarity to active high (DANGEROUS)");
MODULE_LICENSE("GPL");

module_init(sm_it87_init);
module_exit(sm_it87_exit);