lm80.c

《linux驱动程序设计从入门到精通》一书中所有的程序代码含驱动和相应的应用程序

#define show_temp(suffix, value) \
static ssize_t show_temp_##suffix(struct device *dev, char *buf) \
{ \
	struct lm80_data *data = lm80_update_device(dev); \
	return sprintf(buf, "%d\n", TEMP_LIMIT_FROM_REG(data->value)); \
}
show_temp(hot_max, temp_hot_max);
show_temp(hot_hyst, temp_hot_hyst);
show_temp(os_max, temp_os_max);
show_temp(os_hyst, temp_os_hyst);

#define set_temp(suffix, value, reg) \
static ssize_t set_temp_##suffix(struct device *dev, const char *buf, \
	size_t count) \
{ \
	struct i2c_client *client = to_i2c_client(dev); \
	struct lm80_data *data = i2c_get_clientdata(client); \
	long val = simple_strtoul(buf, NULL, 10); \
	data->value = TEMP_LIMIT_TO_REG(val); \
	lm80_write_value(client, reg, data->value); \
	return count; \
}
set_temp(hot_max, temp_hot_max, LM80_REG_TEMP_HOT_MAX);
set_temp(hot_hyst, temp_hot_hyst, LM80_REG_TEMP_HOT_HYST);
set_temp(os_max, temp_os_max, LM80_REG_TEMP_OS_MAX);
set_temp(os_hyst, temp_os_hyst, LM80_REG_TEMP_OS_HYST);

static ssize_t show_alarms(struct device *dev, char *buf)
{
	struct lm80_data *data = lm80_update_device(dev);
	return sprintf(buf, "%d\n", ALARMS_FROM_REG(data->alarms));
}

static DEVICE_ATTR(in0_min, S_IWUSR | S_IRUGO, show_in_min0, set_in_min0);
static DEVICE_ATTR(in1_min, S_IWUSR | S_IRUGO, show_in_min1, set_in_min1);
static DEVICE_ATTR(in2_min, S_IWUSR | S_IRUGO, show_in_min2, set_in_min2);
static DEVICE_ATTR(in3_min, S_IWUSR | S_IRUGO, show_in_min3, set_in_min3);
static DEVICE_ATTR(in4_min, S_IWUSR | S_IRUGO, show_in_min4, set_in_min4);
static DEVICE_ATTR(in5_min, S_IWUSR | S_IRUGO, show_in_min5, set_in_min5);
static DEVICE_ATTR(in6_min, S_IWUSR | S_IRUGO, show_in_min6, set_in_min6);
static DEVICE_ATTR(in0_max, S_IWUSR | S_IRUGO, show_in_max0, set_in_max0);
static DEVICE_ATTR(in1_max, S_IWUSR | S_IRUGO, show_in_max1, set_in_max1);
static DEVICE_ATTR(in2_max, S_IWUSR | S_IRUGO, show_in_max2, set_in_max2);
static DEVICE_ATTR(in3_max, S_IWUSR | S_IRUGO, show_in_max3, set_in_max3);
static DEVICE_ATTR(in4_max, S_IWUSR | S_IRUGO, show_in_max4, set_in_max4);
static DEVICE_ATTR(in5_max, S_IWUSR | S_IRUGO, show_in_max5, set_in_max5);
static DEVICE_ATTR(in6_max, S_IWUSR | S_IRUGO, show_in_max6, set_in_max6);
static DEVICE_ATTR(in0_input, S_IRUGO, show_in_input0, NULL);
static DEVICE_ATTR(in1_input, S_IRUGO, show_in_input1, NULL);
static DEVICE_ATTR(in2_input, S_IRUGO, show_in_input2, NULL);
static DEVICE_ATTR(in3_input, S_IRUGO, show_in_input3, NULL);
static DEVICE_ATTR(in4_input, S_IRUGO, show_in_input4, NULL);
static DEVICE_ATTR(in5_input, S_IRUGO, show_in_input5, NULL);
static DEVICE_ATTR(in6_input, S_IRUGO, show_in_input6, NULL);
static DEVICE_ATTR(fan1_min, S_IWUSR | S_IRUGO, show_fan_min1,
    set_fan_min1);
static DEVICE_ATTR(fan2_min, S_IWUSR | S_IRUGO, show_fan_min2,
    set_fan_min2);
static DEVICE_ATTR(fan1_input, S_IRUGO, show_fan_input1, NULL);
static DEVICE_ATTR(fan2_input, S_IRUGO, show_fan_input2, NULL);
static DEVICE_ATTR(fan1_div, S_IWUSR | S_IRUGO, show_fan_div1, set_fan_div1);
static DEVICE_ATTR(fan2_div, S_IWUSR | S_IRUGO, show_fan_div2, set_fan_div2);
static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_hot_max,
    set_temp_hot_max);
static DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, show_temp_hot_hyst,
    set_temp_hot_hyst);
static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp_os_max,
    set_temp_os_max);
static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_temp_os_hyst,
    set_temp_os_hyst);
static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);

/*
 * Real code
 */

static int lm80_attach_adapter(struct i2c_adapter *adapter)
{
	if (!(adapter->class & I2C_CLASS_HWMON))
		return 0;
	return i2c_detect(adapter, &addr_data, lm80_detect);
}

int lm80_detect(struct i2c_adapter *adapter, int address, int kind)
{
	int i, cur;
	struct i2c_client *new_client;
	struct lm80_data *data;
	int err = 0;
	const char *name;

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
		goto exit;

	/* OK. For now, we presume we have a valid client. We now create the
	   client structure, even though we cannot fill it completely yet.
	   But it allows us to access lm80_{read,write}_value. */
	if (!(data = kmalloc(sizeof(struct lm80_data), GFP_KERNEL))) {
		err = -ENOMEM;
		goto exit;
	}
	memset(data, 0, sizeof(struct lm80_data));

	new_client = &data->client;
	i2c_set_clientdata(new_client, data);
	new_client->addr = address;
	new_client->adapter = adapter;
	new_client->driver = &lm80_driver;
	new_client->flags = 0;

	/* Now, we do the remaining detection. It is lousy. */
	if (lm80_read_value(new_client, LM80_REG_ALARM2) & 0xc0)
		goto error_free;
	for (i = 0x2a; i <= 0x3d; i++) {
		cur = i2c_smbus_read_byte_data(new_client, i);
		if ((i2c_smbus_read_byte_data(new_client, i + 0x40) != cur)
		 || (i2c_smbus_read_byte_data(new_client, i + 0x80) != cur)
		 || (i2c_smbus_read_byte_data(new_client, i + 0xc0) != cur))
		    goto error_free;
	}

	/* Determine the chip type - only one kind supported! */
	kind = lm80;
	name = "lm80";

	/* Fill in the remaining client fields and put it into the global list */
	strlcpy(new_client->name, name, I2C_NAME_SIZE);

	new_client->id = lm80_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)))
		goto error_free;

	/* Initialize the LM80 chip */
	lm80_init_client(new_client);

	/* A few vars need to be filled upon startup */
	data->fan_min[0] = lm80_read_value(new_client, LM80_REG_FAN_MIN(1));
	data->fan_min[1] = lm80_read_value(new_client, LM80_REG_FAN_MIN(2));

	/* Register sysfs hooks */
	device_create_file(&new_client->dev, &dev_attr_in0_min);
	device_create_file(&new_client->dev, &dev_attr_in1_min);
	device_create_file(&new_client->dev, &dev_attr_in2_min);
	device_create_file(&new_client->dev, &dev_attr_in3_min);
	device_create_file(&new_client->dev, &dev_attr_in4_min);
	device_create_file(&new_client->dev, &dev_attr_in5_min);
	device_create_file(&new_client->dev, &dev_attr_in6_min);
	device_create_file(&new_client->dev, &dev_attr_in0_max);
	device_create_file(&new_client->dev, &dev_attr_in1_max);
	device_create_file(&new_client->dev, &dev_attr_in2_max);
	device_create_file(&new_client->dev, &dev_attr_in3_max);
	device_create_file(&new_client->dev, &dev_attr_in4_max);
	device_create_file(&new_client->dev, &dev_attr_in5_max);
	device_create_file(&new_client->dev, &dev_attr_in6_max);
	device_create_file(&new_client->dev, &dev_attr_in0_input);
	device_create_file(&new_client->dev, &dev_attr_in1_input);
	device_create_file(&new_client->dev, &dev_attr_in2_input);
	device_create_file(&new_client->dev, &dev_attr_in3_input);
	device_create_file(&new_client->dev, &dev_attr_in4_input);
	device_create_file(&new_client->dev, &dev_attr_in5_input);
	device_create_file(&new_client->dev, &dev_attr_in6_input);
	device_create_file(&new_client->dev, &dev_attr_fan1_min);
	device_create_file(&new_client->dev, &dev_attr_fan2_min);
	device_create_file(&new_client->dev, &dev_attr_fan1_input);
	device_create_file(&new_client->dev, &dev_attr_fan2_input);
	device_create_file(&new_client->dev, &dev_attr_fan1_div);
	device_create_file(&new_client->dev, &dev_attr_fan2_div);
	device_create_file(&new_client->dev, &dev_attr_temp1_input);
	device_create_file(&new_client->dev, &dev_attr_temp1_max);
	device_create_file(&new_client->dev, &dev_attr_temp1_max_hyst);
	device_create_file(&new_client->dev, &dev_attr_temp1_crit);
	device_create_file(&new_client->dev, &dev_attr_temp1_crit_hyst);
	device_create_file(&new_client->dev, &dev_attr_alarms);

	return 0;

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

static int lm80_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 lm80_read_value(struct i2c_client *client, u8 reg)
{
	return i2c_smbus_read_byte_data(client, reg);
}

static int lm80_write_value(struct i2c_client *client, u8 reg, u8 value)
{
	return i2c_smbus_write_byte_data(client, reg, value);
}

/* Called when we have found a new LM80. */
static void lm80_init_client(struct i2c_client *client)
{
	/* Reset all except Watchdog values and last conversion values
	   This sets fan-divs to 2, among others. This makes most other
	   initializations unnecessary */
	lm80_write_value(client, LM80_REG_CONFIG, 0x80);
	/* Set 11-bit temperature resolution */
	lm80_write_value(client, LM80_REG_RES, 0x08);

	/* Start monitoring */
	lm80_write_value(client, LM80_REG_CONFIG, 0x01);
}

static struct lm80_data *lm80_update_device(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lm80_data *data = i2c_get_clientdata(client);
	int i;

	down(&data->update_lock);

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

		dev_dbg(&client->dev, "Starting lm80 update\n");
		for (i = 0; i <= 6; i++) {
			data->in[i] =
			    lm80_read_value(client, LM80_REG_IN(i));
			data->in_min[i] =
			    lm80_read_value(client, LM80_REG_IN_MIN(i));
			data->in_max[i] =
			    lm80_read_value(client, LM80_REG_IN_MAX(i));
		}
		data->fan[0] = lm80_read_value(client, LM80_REG_FAN1);
		data->fan_min[0] =
		    lm80_read_value(client, LM80_REG_FAN_MIN(1));
		data->fan[1] = lm80_read_value(client, LM80_REG_FAN2);
		data->fan_min[1] =
		    lm80_read_value(client, LM80_REG_FAN_MIN(2));

		data->temp =
		    (lm80_read_value(client, LM80_REG_TEMP) << 8) |
		    (lm80_read_value(client, LM80_REG_RES) & 0xf0);
		data->temp_os_max =
		    lm80_read_value(client, LM80_REG_TEMP_OS_MAX);
		data->temp_os_hyst =
		    lm80_read_value(client, LM80_REG_TEMP_OS_HYST);
		data->temp_hot_max =
		    lm80_read_value(client, LM80_REG_TEMP_HOT_MAX);
		data->temp_hot_hyst =
		    lm80_read_value(client, LM80_REG_TEMP_HOT_HYST);

		i = lm80_read_value(client, LM80_REG_FANDIV);
		data->fan_div[0] = (i >> 2) & 0x03;
		data->fan_div[1] = (i >> 4) & 0x03;
		data->alarms = lm80_read_value(client, LM80_REG_ALARM1) +
		    (lm80_read_value(client, LM80_REG_ALARM2) << 8);
		data->last_updated = jiffies;
		data->valid = 1;
	}

	up(&data->update_lock);

	return data;
}

static int __init sensors_lm80_init(void)
{
	return i2c_add_driver(&lm80_driver);
}

static void __exit sensors_lm80_exit(void)
{
	i2c_del_driver(&lm80_driver);
}

MODULE_AUTHOR("Frodo Looijaard <[e-mail]> and "
	"Philip Edelbrock <[e-mail]>");
MODULE_DESCRIPTION("LM80 driver");
MODULE_LICENSE("GPL");

module_init(sensors_lm80_init);
module_exit(sensors_lm80_exit);