1 /* 2 * LM73 Sensor driver 3 * Based on LM75 4 * 5 * Copyright (C) 2007, CenoSYS (www.cenosys.com). 6 * Copyright (C) 2009, Bollore telecom (www.bolloretelecom.eu). 7 * 8 * Guillaume Ligneul <guillaume.ligneul@gmail.com> 9 * Adrien Demarez <adrien.demarez@bolloretelecom.eu> 10 * Jeremy Laine <jeremy.laine@bolloretelecom.eu> 11 * 12 * This software program is licensed subject to the GNU General Public License 13 * (GPL).Version 2,June 1991, available at 14 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html 15 */ 16 17 #include <linux/module.h> 18 #include <linux/init.h> 19 #include <linux/slab.h> 20 #include <linux/i2c.h> 21 #include <linux/hwmon.h> 22 #include <linux/hwmon-sysfs.h> 23 #include <linux/err.h> 24 25 26 /* Addresses scanned */ 27 static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4c, 28 0x4d, 0x4e, I2C_CLIENT_END }; 29 30 /* Insmod parameters */ 31 I2C_CLIENT_INSMOD_1(lm73); 32 33 /* LM73 registers */ 34 #define LM73_REG_INPUT 0x00 35 #define LM73_REG_CONF 0x01 36 #define LM73_REG_MAX 0x02 37 #define LM73_REG_MIN 0x03 38 #define LM73_REG_CTRL 0x04 39 #define LM73_REG_ID 0x07 40 41 #define LM73_ID 0x9001 /* or 0x190 after a swab16() */ 42 #define DRVNAME "lm73" 43 #define LM73_TEMP_MIN (-40) 44 #define LM73_TEMP_MAX 150 45 46 /*-----------------------------------------------------------------------*/ 47 48 49 static ssize_t set_temp(struct device *dev, struct device_attribute *da, 50 const char *buf, size_t count) 51 { 52 struct sensor_device_attribute *attr = to_sensor_dev_attr(da); 53 struct i2c_client *client = to_i2c_client(dev); 54 long temp; 55 short value; 56 57 int status = strict_strtol(buf, 10, &temp); 58 if (status < 0) 59 return status; 60 61 /* Write value */ 62 value = (short) SENSORS_LIMIT(temp/250, (LM73_TEMP_MIN*4), 63 (LM73_TEMP_MAX*4)) << 5; 64 i2c_smbus_write_word_data(client, attr->index, swab16(value)); 65 return count; 66 } 67 68 static ssize_t show_temp(struct device *dev, struct device_attribute *da, 69 char *buf) 70 { 71 struct sensor_device_attribute *attr = to_sensor_dev_attr(da); 72 struct i2c_client *client = to_i2c_client(dev); 73 /* use integer division instead of equivalent right shift to 74 guarantee arithmetic shift and preserve the sign */ 75 int temp = ((s16) (swab16(i2c_smbus_read_word_data(client, 76 attr->index)))*250) / 32; 77 return sprintf(buf, "%d\n", temp); 78 } 79 80 81 /*-----------------------------------------------------------------------*/ 82 83 /* sysfs attributes for hwmon */ 84 85 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, 86 show_temp, set_temp, LM73_REG_MAX); 87 static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, 88 show_temp, set_temp, LM73_REG_MIN); 89 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, 90 show_temp, NULL, LM73_REG_INPUT); 91 92 93 static struct attribute *lm73_attributes[] = { 94 &sensor_dev_attr_temp1_input.dev_attr.attr, 95 &sensor_dev_attr_temp1_max.dev_attr.attr, 96 &sensor_dev_attr_temp1_min.dev_attr.attr, 97 98 NULL 99 }; 100 101 static const struct attribute_group lm73_group = { 102 .attrs = lm73_attributes, 103 }; 104 105 /*-----------------------------------------------------------------------*/ 106 107 /* device probe and removal */ 108 109 static int 110 lm73_probe(struct i2c_client *client, const struct i2c_device_id *id) 111 { 112 struct device *hwmon_dev; 113 int status; 114 115 /* Register sysfs hooks */ 116 status = sysfs_create_group(&client->dev.kobj, &lm73_group); 117 if (status) 118 return status; 119 120 hwmon_dev = hwmon_device_register(&client->dev); 121 if (IS_ERR(hwmon_dev)) { 122 status = PTR_ERR(hwmon_dev); 123 goto exit_remove; 124 } 125 i2c_set_clientdata(client, hwmon_dev); 126 127 dev_info(&client->dev, "%s: sensor '%s'\n", 128 dev_name(hwmon_dev), client->name); 129 130 return 0; 131 132 exit_remove: 133 sysfs_remove_group(&client->dev.kobj, &lm73_group); 134 return status; 135 } 136 137 static int lm73_remove(struct i2c_client *client) 138 { 139 struct device *hwmon_dev = i2c_get_clientdata(client); 140 141 hwmon_device_unregister(hwmon_dev); 142 sysfs_remove_group(&client->dev.kobj, &lm73_group); 143 i2c_set_clientdata(client, NULL); 144 return 0; 145 } 146 147 static const struct i2c_device_id lm73_ids[] = { 148 { "lm73", lm73 }, 149 { /* LIST END */ } 150 }; 151 MODULE_DEVICE_TABLE(i2c, lm73_ids); 152 153 /* Return 0 if detection is successful, -ENODEV otherwise */ 154 static int lm73_detect(struct i2c_client *new_client, 155 struct i2c_board_info *info) 156 { 157 struct i2c_adapter *adapter = new_client->adapter; 158 u16 id; 159 u8 ctrl; 160 161 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | 162 I2C_FUNC_SMBUS_WORD_DATA)) 163 return -ENODEV; 164 165 /* Check device ID */ 166 id = i2c_smbus_read_word_data(new_client, LM73_REG_ID); 167 ctrl = i2c_smbus_read_byte_data(new_client, LM73_REG_CTRL); 168 if ((id != LM73_ID) || (ctrl & 0x10)) 169 return -ENODEV; 170 171 strlcpy(info->type, "lm73", I2C_NAME_SIZE); 172 173 return 0; 174 } 175 176 static struct i2c_driver lm73_driver = { 177 .class = I2C_CLASS_HWMON, 178 .driver = { 179 .name = "lm73", 180 }, 181 .probe = lm73_probe, 182 .remove = lm73_remove, 183 .id_table = lm73_ids, 184 .detect = lm73_detect, 185 .address_list = normal_i2c, 186 }; 187 188 /* module glue */ 189 190 static int __init sensors_lm73_init(void) 191 { 192 return i2c_add_driver(&lm73_driver); 193 } 194 195 static void __exit sensors_lm73_exit(void) 196 { 197 i2c_del_driver(&lm73_driver); 198 } 199 200 MODULE_AUTHOR("Guillaume Ligneul <guillaume.ligneul@gmail.com>"); 201 MODULE_DESCRIPTION("LM73 driver"); 202 MODULE_LICENSE("GPL"); 203 204 module_init(sensors_lm73_init); 205 module_exit(sensors_lm73_exit); 206