| /* Texas Instruments TMP102 SMBus temperature sensor driver |
| * |
| * Copyright (C) 2010 Steven King <sfking@fdwdc.com> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/slab.h> |
| #include <linux/i2c.h> |
| #include <linux/hwmon.h> |
| #include <linux/hwmon-sysfs.h> |
| #include <linux/err.h> |
| #include <linux/mutex.h> |
| #include <linux/device.h> |
| |
| #define DRIVER_NAME "tmp102" |
| |
| #define TMP102_TEMP_REG 0x00 |
| #define TMP102_CONF_REG 0x01 |
| /* note: these bit definitions are byte swapped */ |
| #define TMP102_CONF_SD 0x0100 |
| #define TMP102_CONF_TM 0x0200 |
| #define TMP102_CONF_POL 0x0400 |
| #define TMP102_CONF_F0 0x0800 |
| #define TMP102_CONF_F1 0x1000 |
| #define TMP102_CONF_R0 0x2000 |
| #define TMP102_CONF_R1 0x4000 |
| #define TMP102_CONF_OS 0x8000 |
| #define TMP102_CONF_EM 0x0010 |
| #define TMP102_CONF_AL 0x0020 |
| #define TMP102_CONF_CR0 0x0040 |
| #define TMP102_CONF_CR1 0x0080 |
| #define TMP102_TLOW_REG 0x02 |
| #define TMP102_THIGH_REG 0x03 |
| |
| struct tmp102 { |
| struct device *hwmon_dev; |
| struct mutex lock; |
| u16 config_orig; |
| unsigned long last_update; |
| int temp[3]; |
| }; |
| |
| /* SMBus specifies low byte first, but the TMP102 returns high byte first, |
| * so we have to swab16 the values */ |
| static inline int tmp102_read_reg(struct i2c_client *client, u8 reg) |
| { |
| int result = i2c_smbus_read_word_data(client, reg); |
| return result < 0 ? result : swab16(result); |
| } |
| |
| static inline int tmp102_write_reg(struct i2c_client *client, u8 reg, u16 val) |
| { |
| return i2c_smbus_write_word_data(client, reg, swab16(val)); |
| } |
| |
| /* convert left adjusted 13-bit TMP102 register value to milliCelsius */ |
| static inline int tmp102_reg_to_mC(s16 val) |
| { |
| return ((val & ~0x01) * 1000) / 128; |
| } |
| |
| /* convert milliCelsius to left adjusted 13-bit TMP102 register value */ |
| static inline u16 tmp102_mC_to_reg(int val) |
| { |
| return (val * 128) / 1000; |
| } |
| |
| static const u8 tmp102_reg[] = { |
| TMP102_TEMP_REG, |
| TMP102_TLOW_REG, |
| TMP102_THIGH_REG, |
| }; |
| |
| static struct tmp102 *tmp102_update_device(struct i2c_client *client) |
| { |
| struct tmp102 *tmp102 = i2c_get_clientdata(client); |
| |
| mutex_lock(&tmp102->lock); |
| if (time_after(jiffies, tmp102->last_update + HZ / 3)) { |
| int i; |
| for (i = 0; i < ARRAY_SIZE(tmp102->temp); ++i) { |
| int status = tmp102_read_reg(client, tmp102_reg[i]); |
| if (status > -1) |
| tmp102->temp[i] = tmp102_reg_to_mC(status); |
| } |
| tmp102->last_update = jiffies; |
| } |
| mutex_unlock(&tmp102->lock); |
| return tmp102; |
| } |
| |
| static ssize_t tmp102_show_temp(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct sensor_device_attribute *sda = to_sensor_dev_attr(attr); |
| struct tmp102 *tmp102 = tmp102_update_device(to_i2c_client(dev)); |
| |
| return sprintf(buf, "%d\n", tmp102->temp[sda->index]); |
| } |
| |
| static ssize_t tmp102_set_temp(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, size_t count) |
| { |
| struct sensor_device_attribute *sda = to_sensor_dev_attr(attr); |
| struct i2c_client *client = to_i2c_client(dev); |
| struct tmp102 *tmp102 = i2c_get_clientdata(client); |
| long val; |
| int status; |
| |
| if (strict_strtol(buf, 10, &val) < 0) |
| return -EINVAL; |
| val = SENSORS_LIMIT(val, -256000, 255000); |
| |
| mutex_lock(&tmp102->lock); |
| tmp102->temp[sda->index] = val; |
| status = tmp102_write_reg(client, tmp102_reg[sda->index], |
| tmp102_mC_to_reg(val)); |
| mutex_unlock(&tmp102->lock); |
| return status ? : count; |
| } |
| |
| static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL , 0); |
| |
| static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, tmp102_show_temp, |
| tmp102_set_temp, 1); |
| |
| static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, tmp102_show_temp, |
| tmp102_set_temp, 2); |
| |
| static struct attribute *tmp102_attributes[] = { |
| &sensor_dev_attr_temp1_input.dev_attr.attr, |
| &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, |
| &sensor_dev_attr_temp1_max.dev_attr.attr, |
| NULL |
| }; |
| |
| static const struct attribute_group tmp102_attr_group = { |
| .attrs = tmp102_attributes, |
| }; |
| |
| #define TMP102_CONFIG (TMP102_CONF_TM | TMP102_CONF_EM | TMP102_CONF_CR1) |
| #define TMP102_CONFIG_RD_ONLY (TMP102_CONF_R0 | TMP102_CONF_R1 | TMP102_CONF_AL) |
| |
| static int __devinit tmp102_probe(struct i2c_client *client, |
| const struct i2c_device_id *id) |
| { |
| struct tmp102 *tmp102; |
| int status; |
| |
| if (!i2c_check_functionality(client->adapter, |
| I2C_FUNC_SMBUS_WORD_DATA)) { |
| dev_err(&client->dev, "adapter doesnt support SMBus word " |
| "transactions\n"); |
| return -ENODEV; |
| } |
| |
| tmp102 = kzalloc(sizeof(*tmp102), GFP_KERNEL); |
| if (!tmp102) { |
| dev_dbg(&client->dev, "kzalloc failed\n"); |
| return -ENOMEM; |
| } |
| i2c_set_clientdata(client, tmp102); |
| |
| status = tmp102_read_reg(client, TMP102_CONF_REG); |
| if (status < 0) { |
| dev_err(&client->dev, "error reading config register\n"); |
| goto fail_free; |
| } |
| tmp102->config_orig = status; |
| status = tmp102_write_reg(client, TMP102_CONF_REG, TMP102_CONFIG); |
| if (status < 0) { |
| dev_err(&client->dev, "error writing config register\n"); |
| goto fail_restore_config; |
| } |
| status = tmp102_read_reg(client, TMP102_CONF_REG); |
| if (status < 0) { |
| dev_err(&client->dev, "error reading config register\n"); |
| goto fail_restore_config; |
| } |
| status &= ~TMP102_CONFIG_RD_ONLY; |
| if (status != TMP102_CONFIG) { |
| dev_err(&client->dev, "config settings did not stick\n"); |
| status = -ENODEV; |
| goto fail_restore_config; |
| } |
| tmp102->last_update = jiffies - HZ; |
| mutex_init(&tmp102->lock); |
| |
| status = sysfs_create_group(&client->dev.kobj, &tmp102_attr_group); |
| if (status) { |
| dev_dbg(&client->dev, "could not create sysfs files\n"); |
| goto fail_restore_config; |
| } |
| tmp102->hwmon_dev = hwmon_device_register(&client->dev); |
| if (IS_ERR(tmp102->hwmon_dev)) { |
| dev_dbg(&client->dev, "unable to register hwmon device\n"); |
| status = PTR_ERR(tmp102->hwmon_dev); |
| goto fail_remove_sysfs; |
| } |
| |
| dev_info(&client->dev, "initialized\n"); |
| |
| return 0; |
| |
| fail_remove_sysfs: |
| sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group); |
| fail_restore_config: |
| tmp102_write_reg(client, TMP102_CONF_REG, tmp102->config_orig); |
| fail_free: |
| i2c_set_clientdata(client, NULL); |
| kfree(tmp102); |
| |
| return status; |
| } |
| |
| static int __devexit tmp102_remove(struct i2c_client *client) |
| { |
| struct tmp102 *tmp102 = i2c_get_clientdata(client); |
| |
| hwmon_device_unregister(tmp102->hwmon_dev); |
| sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group); |
| |
| /* Stop monitoring if device was stopped originally */ |
| if (tmp102->config_orig & TMP102_CONF_SD) { |
| int config; |
| |
| config = tmp102_read_reg(client, TMP102_CONF_REG); |
| if (config >= 0) |
| tmp102_write_reg(client, TMP102_CONF_REG, |
| config | TMP102_CONF_SD); |
| } |
| |
| i2c_set_clientdata(client, NULL); |
| kfree(tmp102); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM |
| static int tmp102_suspend(struct device *dev) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| int config; |
| |
| config = tmp102_read_reg(client, TMP102_CONF_REG); |
| if (config < 0) |
| return config; |
| |
| config |= TMP102_CONF_SD; |
| return tmp102_write_reg(client, TMP102_CONF_REG, config); |
| } |
| |
| static int tmp102_resume(struct device *dev) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| int config; |
| |
| config = tmp102_read_reg(client, TMP102_CONF_REG); |
| if (config < 0) |
| return config; |
| |
| config &= ~TMP102_CONF_SD; |
| return tmp102_write_reg(client, TMP102_CONF_REG, config); |
| } |
| |
| static const struct dev_pm_ops tmp102_dev_pm_ops = { |
| .suspend = tmp102_suspend, |
| .resume = tmp102_resume, |
| }; |
| |
| #define TMP102_DEV_PM_OPS (&tmp102_dev_pm_ops) |
| #else |
| #define TMP102_DEV_PM_OPS NULL |
| #endif /* CONFIG_PM */ |
| |
| static const struct i2c_device_id tmp102_id[] = { |
| { "tmp102", 0 }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(i2c, tmp102_id); |
| |
| static struct i2c_driver tmp102_driver = { |
| .driver.name = DRIVER_NAME, |
| .driver.pm = TMP102_DEV_PM_OPS, |
| .probe = tmp102_probe, |
| .remove = __devexit_p(tmp102_remove), |
| .id_table = tmp102_id, |
| }; |
| |
| static int __init tmp102_init(void) |
| { |
| return i2c_add_driver(&tmp102_driver); |
| } |
| module_init(tmp102_init); |
| |
| static void __exit tmp102_exit(void) |
| { |
| i2c_del_driver(&tmp102_driver); |
| } |
| module_exit(tmp102_exit); |
| |
| MODULE_AUTHOR("Steven King <sfking@fdwdc.com>"); |
| MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver"); |
| MODULE_LICENSE("GPL"); |