u32 val; \
         \
        val = simple_strtoul(buf, NULL, 10); \
+       mutex_lock(&data->update_lock); \
        data->in_##reg[nr] = SENSORS_LIMIT(IN_TO_REG(nr, val)/4, 0, 255); \
        w83792d_write_value(client, W83792D_REG_IN_##REG[nr], data->in_##reg[nr]); \
+       mutex_unlock(&data->update_lock); \
         \
        return count; \
 }
        u32 val;
 
        val = simple_strtoul(buf, NULL, 10);
+       mutex_lock(&data->update_lock);
        data->fan_min[nr] = FAN_TO_REG(val, DIV_FROM_REG(data->fan_div[nr]));
        w83792d_write_value(client, W83792D_REG_FAN_MIN[nr],
                                data->fan_min[nr]);
+       mutex_unlock(&data->update_lock);
 
        return count;
 }
        u8 tmp_fan_div;
 
        /* Save fan_min */
+       mutex_lock(&data->update_lock);
        min = FAN_FROM_REG(data->fan_min[nr],
                           DIV_FROM_REG(data->fan_div[nr]));
 
        /* Restore fan_min */
        data->fan_min[nr] = FAN_TO_REG(min, DIV_FROM_REG(data->fan_div[nr]));
        w83792d_write_value(client, W83792D_REG_FAN_MIN[nr], data->fan_min[nr]);
+       mutex_unlock(&data->update_lock);
 
        return count;
 }
        s32 val;
 
        val = simple_strtol(buf, NULL, 10);
-
+       mutex_lock(&data->update_lock);
        data->temp1[nr] = TEMP1_TO_REG(val);
        w83792d_write_value(client, W83792D_REG_TEMP1[nr],
                data->temp1[nr]);
+       mutex_unlock(&data->update_lock);
 
        return count;
 }
        s32 val;
 
        val = simple_strtol(buf, NULL, 10);
-
+       mutex_lock(&data->update_lock);
        data->temp_add[nr][index] = TEMP_ADD_TO_REG_HIGH(val);
        data->temp_add[nr][index+1] = TEMP_ADD_TO_REG_LOW(val);
        w83792d_write_value(client, W83792D_REG_TEMP_ADD[nr][index],
                data->temp_add[nr][index]);
        w83792d_write_value(client, W83792D_REG_TEMP_ADD[nr][index+1],
                data->temp_add[nr][index+1]);
+       mutex_unlock(&data->update_lock);
 
        return count;
 }
        u8 fan_cfg_tmp, cfg1_tmp, cfg2_tmp, cfg3_tmp, cfg4_tmp;
 
        val = simple_strtoul(buf, NULL, 10);
+       if (val < 1 || val > 3)
+               return -EINVAL;
+
+       mutex_lock(&data->update_lock);
        switch (val) {
        case 1:
                data->pwmenable[nr] = 0; /* manual mode */
        case 3:
                data->pwmenable[nr] = 1; /* thermal cruise/Smart Fan I */
                break;
-       default:
-               return -EINVAL;
        }
        cfg1_tmp = data->pwmenable[0];
        cfg2_tmp = (data->pwmenable[1]) << 2;
        cfg4_tmp = w83792d_read_value(client,W83792D_REG_FAN_CFG) & 0xc0;
        fan_cfg_tmp = ((cfg4_tmp | cfg3_tmp) | cfg2_tmp) | cfg1_tmp;
        w83792d_write_value(client, W83792D_REG_FAN_CFG, fan_cfg_tmp);
+       mutex_unlock(&data->update_lock);
 
        return count;
 }
        u8 temp1 = 0, temp2 = 0;
 
        val = simple_strtoul(buf, NULL, 10);
-
+       mutex_lock(&data->update_lock);
        data->chassis_clear = SENSORS_LIMIT(val, 0 ,1);
        temp1 = ((data->chassis_clear) << 7) & 0x80;
        temp2 = w83792d_read_value(client,
                W83792D_REG_CHASSIS_CLR) & 0x7f;
        w83792d_write_value(client, W83792D_REG_CHASSIS_CLR, temp1 | temp2);
+       mutex_unlock(&data->update_lock);
 
        return count;
 }
        val = simple_strtoul(buf, NULL, 10);
        target_tmp = val;
        target_tmp = target_tmp & 0x7f;
+       mutex_lock(&data->update_lock);
        target_mask = w83792d_read_value(client, W83792D_REG_THERMAL[nr]) & 0x80;
        data->thermal_cruise[nr] = SENSORS_LIMIT(target_tmp, 0, 255);
        w83792d_write_value(client, W83792D_REG_THERMAL[nr],
                (data->thermal_cruise[nr]) | target_mask);
+       mutex_unlock(&data->update_lock);
 
        return count;
 }
        u8 tol_tmp, tol_mask;
 
        val = simple_strtoul(buf, NULL, 10);
+       mutex_lock(&data->update_lock);
        tol_mask = w83792d_read_value(client,
                W83792D_REG_TOLERANCE[nr]) & ((nr == 1) ? 0x0f : 0xf0);
        tol_tmp = SENSORS_LIMIT(val, 0, 15);
        }
        w83792d_write_value(client, W83792D_REG_TOLERANCE[nr],
                tol_mask | tol_tmp);
+       mutex_unlock(&data->update_lock);
 
        return count;
 }
        u8 mask_tmp = 0;
 
        val = simple_strtoul(buf, NULL, 10);
+       mutex_lock(&data->update_lock);
        data->sf2_points[index][nr] = SENSORS_LIMIT(val, 0, 127);
        mask_tmp = w83792d_read_value(client,
                                        W83792D_REG_POINTS[index][nr]) & 0x80;
        w83792d_write_value(client, W83792D_REG_POINTS[index][nr],
                mask_tmp|data->sf2_points[index][nr]);
+       mutex_unlock(&data->update_lock);
 
        return count;
 }
        u8 mask_tmp=0, level_tmp=0;
 
        val = simple_strtoul(buf, NULL, 10);
+       mutex_lock(&data->update_lock);
        data->sf2_levels[index][nr] = SENSORS_LIMIT((val * 15) / 100, 0, 15);
        mask_tmp = w83792d_read_value(client, W83792D_REG_LEVELS[index][nr])
                & ((nr==3) ? 0xf0 : 0x0f);
                level_tmp = data->sf2_levels[index][nr] << 4;
        }
        w83792d_write_value(client, W83792D_REG_LEVELS[index][nr], level_tmp | mask_tmp);
+       mutex_unlock(&data->update_lock);
 
        return count;
 }