+static ssize_t show_pwm_at_crit(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ struct adt7475_data *data = adt7475_update_device(dev);
+ return sprintf(buf, "%d\n", !!(data->config4 & CONFIG4_MAXDUTY));
+}
+
+static ssize_t set_pwm_at_crit(struct device *dev,
+ struct device_attribute *devattr,
+ const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct adt7475_data *data = i2c_get_clientdata(client);
+ long val;
+
+ if (strict_strtol(buf, 10, &val))
+ return -EINVAL;
+ if (val != 0 && val != 1)
+ return -EINVAL;
+
+ mutex_lock(&data->lock);
+ data->config4 = i2c_smbus_read_byte_data(client, REG_CONFIG4);
+ if (val)
+ data->config4 |= CONFIG4_MAXDUTY;
+ else
+ data->config4 &= ~CONFIG4_MAXDUTY;
+ i2c_smbus_write_byte_data(client, REG_CONFIG4, data->config4);
+ mutex_unlock(&data->lock);
+
+ return count;
+}
+