fscher.c

i2c 的 驱动的源码

	data->valid = 0;
	init_MUTEX(&data->update_lock);

	/* Tell the I2C layer a new client has arrived */
	if ((err = i2c_attach_client(new_client)))
		goto exit_free;

	fscher_init_client(new_client);

	/* Register sysfs hooks */
	device_create_file_revision(new_client);
	device_create_file_alarms(new_client);
	device_create_file_control(new_client);
	device_create_file_watchdog(new_client);

	device_create_file_in(new_client, 0);
	device_create_file_in(new_client, 1);
	device_create_file_in(new_client, 2);

	device_create_file_fan(new_client, 1);
	device_create_file_fan(new_client, 2);
	device_create_file_fan(new_client, 3);

	device_create_file_temp(new_client, 1);
	device_create_file_temp(new_client, 2);
	device_create_file_temp(new_client, 3);

	return 0;

exit_free:
	kfree(data);
exit:
	return err;
}

static int fscher_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 int fscher_read_value(struct i2c_client *client, u8 reg)
{
	dev_dbg(&client->dev, "read reg 0x%02x\n", reg);

	return i2c_smbus_read_byte_data(client, reg);
}

static int fscher_write_value(struct i2c_client *client, u8 reg, u8 value)
{
	dev_dbg(&client->dev, "write reg 0x%02x, val 0x%02x\n",
		reg, value);

	return i2c_smbus_write_byte_data(client, reg, value);
}

/* Called when we have found a new FSC Hermes. */
static void fscher_init_client(struct i2c_client *client)
{
	struct fscher_data *data = i2c_get_clientdata(client);

	/* Read revision from chip */
	data->revision =  fscher_read_value(client, FSCHER_REG_REVISION);
}

static struct fscher_data *fscher_update_device(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct fscher_data *data = i2c_get_clientdata(client);

	down(&data->update_lock);

	if ((jiffies - data->last_updated > 2 * HZ) ||
	    (jiffies < data->last_updated) || !data->valid) {

		dev_dbg(&client->dev, "Starting fscher update\n");

		data->temp_act[0] = fscher_read_value(client, FSCHER_REG_TEMP0_ACT);
		data->temp_act[1] = fscher_read_value(client, FSCHER_REG_TEMP1_ACT);
		data->temp_act[2] = fscher_read_value(client, FSCHER_REG_TEMP2_ACT);
		data->temp_status[0] = fscher_read_value(client, FSCHER_REG_TEMP0_STATE);
		data->temp_status[1] = fscher_read_value(client, FSCHER_REG_TEMP1_STATE);
		data->temp_status[2] = fscher_read_value(client, FSCHER_REG_TEMP2_STATE);

		data->volt[0] = fscher_read_value(client, FSCHER_REG_VOLT_12);
		data->volt[1] = fscher_read_value(client, FSCHER_REG_VOLT_5);
		data->volt[2] = fscher_read_value(client, FSCHER_REG_VOLT_BATT);

		data->fan_act[0] = fscher_read_value(client, FSCHER_REG_FAN0_ACT);
		data->fan_act[1] = fscher_read_value(client, FSCHER_REG_FAN1_ACT);
		data->fan_act[2] = fscher_read_value(client, FSCHER_REG_FAN2_ACT);
		data->fan_status[0] = fscher_read_value(client, FSCHER_REG_FAN0_STATE);
		data->fan_status[1] = fscher_read_value(client, FSCHER_REG_FAN1_STATE);
		data->fan_status[2] = fscher_read_value(client, FSCHER_REG_FAN2_STATE);
		data->fan_min[0] = fscher_read_value(client, FSCHER_REG_FAN0_MIN);
		data->fan_min[1] = fscher_read_value(client, FSCHER_REG_FAN1_MIN);
		data->fan_min[2] = fscher_read_value(client, FSCHER_REG_FAN2_MIN);
		data->fan_ripple[0] = fscher_read_value(client, FSCHER_REG_FAN0_RIPPLE);
		data->fan_ripple[1] = fscher_read_value(client, FSCHER_REG_FAN1_RIPPLE);
		data->fan_ripple[2] = fscher_read_value(client, FSCHER_REG_FAN2_RIPPLE);

		data->watchdog[0] = fscher_read_value(client, FSCHER_REG_WDOG_PRESET);
		data->watchdog[1] = fscher_read_value(client, FSCHER_REG_WDOG_STATE);
		data->watchdog[2] = fscher_read_value(client, FSCHER_REG_WDOG_CONTROL);

		data->global_event = fscher_read_value(client, FSCHER_REG_EVENT_STATE);

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

	up(&data->update_lock);

	return data;
}



#define FAN_INDEX_FROM_NUM(nr)	((nr) - 1)

static ssize_t set_fan_status(struct i2c_client *client, struct fscher_data *data,
			      const char *buf, size_t count, int nr, int reg)
{
	/* bits 0..1, 3..7 reserved => mask with 0x04 */  
	unsigned long v = simple_strtoul(buf, NULL, 10) & 0x04;
	data->fan_status[FAN_INDEX_FROM_NUM(nr)] &= ~v;

	fscher_write_value(client, reg, v);
	return count;
}

static ssize_t show_fan_status(struct fscher_data *data, char *buf, int nr)
{
	/* bits 0..1, 3..7 reserved => mask with 0x04 */  
	return sprintf(buf, "%u\n", data->fan_status[FAN_INDEX_FROM_NUM(nr)] & 0x04);
}

static ssize_t set_fan_pwm(struct i2c_client *client, struct fscher_data *data,
		       const char *buf, size_t count, int nr, int reg)
{
	data->fan_min[FAN_INDEX_FROM_NUM(nr)] = simple_strtoul(buf, NULL, 10) & 0xff;

	fscher_write_value(client, reg, data->fan_min[FAN_INDEX_FROM_NUM(nr)]);
	return count;
}

static ssize_t show_fan_pwm (struct fscher_data *data, char *buf, int nr)
{
	return sprintf(buf, "%u\n", data->fan_min[FAN_INDEX_FROM_NUM(nr)]);
}

static ssize_t set_fan_div(struct i2c_client *client, struct fscher_data *data,
			   const char *buf, size_t count, int nr, int reg)
{
	/* supported values: 2, 4, 8 */
	unsigned long v = simple_strtoul(buf, NULL, 10);

	switch (v) {
	case 2: v = 1; break;
	case 4: v = 2; break;
	case 8: v = 3; break;
	default:
		dev_err(&client->dev, "fan_div value %ld not "
			 "supported. Choose one of 2, 4 or 8!\n", v);
		return -EINVAL;
	}

	/* bits 2..7 reserved => mask with 0x03 */
	data->fan_ripple[FAN_INDEX_FROM_NUM(nr)] &= ~0x03;
	data->fan_ripple[FAN_INDEX_FROM_NUM(nr)] |= v;

	fscher_write_value(client, reg, data->fan_ripple[FAN_INDEX_FROM_NUM(nr)]);
	return count;
}

static ssize_t show_fan_div(struct fscher_data *data, char *buf, int nr)
{
	/* bits 2..7 reserved => mask with 0x03 */  
	return sprintf(buf, "%u\n", 1 << (data->fan_ripple[FAN_INDEX_FROM_NUM(nr)] & 0x03));
}

#define RPM_FROM_REG(val)	(val*60)

static ssize_t show_fan_input (struct fscher_data *data, char *buf, int nr)
{
	return sprintf(buf, "%u\n", RPM_FROM_REG(data->fan_act[FAN_INDEX_FROM_NUM(nr)]));
}



#define TEMP_INDEX_FROM_NUM(nr)		((nr) - 1)

static ssize_t set_temp_status(struct i2c_client *client, struct fscher_data *data,
			       const char *buf, size_t count, int nr, int reg)
{
	/* bits 2..7 reserved, 0 read only => mask with 0x02 */  
	unsigned long v = simple_strtoul(buf, NULL, 10) & 0x02;
	data->temp_status[TEMP_INDEX_FROM_NUM(nr)] &= ~v;

	fscher_write_value(client, reg, v);
	return count;
}

static ssize_t show_temp_status(struct fscher_data *data, char *buf, int nr)
{
	/* bits 2..7 reserved => mask with 0x03 */
	return sprintf(buf, "%u\n", data->temp_status[TEMP_INDEX_FROM_NUM(nr)] & 0x03);
}

#define TEMP_FROM_REG(val)	(((val) - 128) * 1000)

static ssize_t show_temp_input(struct fscher_data *data, char *buf, int nr)
{
	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_act[TEMP_INDEX_FROM_NUM(nr)]));
}

/*
 * The final conversion is specified in sensors.conf, as it depends on
 * mainboard specific values. We export the registers contents as
 * pseudo-hundredths-of-Volts (range 0V - 2.55V). Not that it makes much
 * sense per se, but it minimizes the conversions count and keeps the
 * values within a usual range.
 */
#define VOLT_FROM_REG(val)	((val) * 10)

static ssize_t show_in_input(struct fscher_data *data, char *buf, int nr)
{
	return sprintf(buf, "%u\n", VOLT_FROM_REG(data->volt[nr]));
}



static ssize_t show_revision(struct fscher_data *data, char *buf, int nr)
{
	return sprintf(buf, "%u\n", data->revision);
}



static ssize_t show_alarms(struct fscher_data *data, char *buf, int nr)
{
	/* bits 2, 5..6 reserved => mask with 0x9b */
	return sprintf(buf, "%u\n", data->global_event & 0x9b);
}



static ssize_t set_control(struct i2c_client *client, struct fscher_data *data,
			   const char *buf, size_t count, int nr, int reg)
{
	/* bits 1..7 reserved => mask with 0x01 */  
	unsigned long v = simple_strtoul(buf, NULL, 10) & 0x01;
	data->global_control &= ~v;

	fscher_write_value(client, reg, v);
	return count;
}

static ssize_t show_control(struct fscher_data *data, char *buf, int nr)
{
	/* bits 1..7 reserved => mask with 0x01 */
	return sprintf(buf, "%u\n", data->global_control & 0x01);
}



static ssize_t set_watchdog_control(struct i2c_client *client, struct
				    fscher_data *data, const char *buf, size_t count,
				    int nr, int reg)
{
	/* bits 0..3 reserved => mask with 0xf0 */  
	unsigned long v = simple_strtoul(buf, NULL, 10) & 0xf0;
	data->watchdog[2] &= ~0xf0;
	data->watchdog[2] |= v;

	fscher_write_value(client, reg, data->watchdog[2]);
	return count;
}

static ssize_t show_watchdog_control(struct fscher_data *data, char *buf, int nr)
{
	/* bits 0..3 reserved, bit 5 write only => mask with 0xd0 */
	return sprintf(buf, "%u\n", data->watchdog[2] & 0xd0);
}

static ssize_t set_watchdog_status(struct i2c_client *client, struct fscher_data *data,
				   const char *buf, size_t count, int nr, int reg)
{
	/* bits 0, 2..7 reserved => mask with 0x02 */  
	unsigned long v = simple_strtoul(buf, NULL, 10) & 0x02;
	data->watchdog[1] &= ~v;

	fscher_write_value(client, reg, v);
	return count;
}

static ssize_t show_watchdog_status(struct fscher_data *data, char *buf, int nr)
{
	/* bits 0, 2..7 reserved => mask with 0x02 */
	return sprintf(buf, "%u\n", data->watchdog[1] & 0x02);
}

static ssize_t set_watchdog_preset(struct i2c_client *client, struct fscher_data *data,
				   const char *buf, size_t count, int nr, int reg)
{
	data->watchdog[0] = simple_strtoul(buf, NULL, 10) & 0xff;

	fscher_write_value(client, reg, data->watchdog[0]);
	return count;
}

static ssize_t show_watchdog_preset(struct fscher_data *data, char *buf, int nr)
{
	return sprintf(buf, "%u\n", data->watchdog[0]);
}

static int __init sensors_fscher_init(void)
{
	return i2c_add_driver(&fscher_driver);
}

static void __exit sensors_fscher_exit(void)
{
	i2c_del_driver(&fscher_driver);
}

MODULE_AUTHOR("Reinhard Nissl <[e-mail]>");
MODULE_DESCRIPTION("FSC Hermes driver");
MODULE_LICENSE("GPL");

module_init(sensors_fscher_init);
module_exit(sensors_fscher_exit);