drivers/hwmon/emc1403.c

   1 /*
   2  * emc1403.c - SMSC Thermal Driver
   3  *
   4  * Copyright (C) 2008 Intel Corp
   5  *
   6  *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; version 2 of the License.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  20  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  21  *
  22  * TODO
  23  *      -       cache alarm and critical limit registers
  24  *      -       add emc1404 support
  25  */
  26
  27 #include <linux/module.h>
  28 #include <linux/init.h>
  29 #include <linux/slab.h>
  30 #include <linux/i2c.h>
  31 #include <linux/hwmon.h>
  32 #include <linux/hwmon-sysfs.h>
  33 #include <linux/err.h>
  34 #include <linux/sysfs.h>
  35 #include <linux/mutex.h>
  36
  37 #define THERMAL_PID_REG         0xfd
  38 #define THERMAL_SMSC_ID_REG     0xfe
  39 #define THERMAL_REVISION_REG    0xff
  40
  41 struct thermal_data {
  42         struct device *hwmon_dev;
  43         struct mutex mutex;
  44         /*
  45          * Cache the hyst value so we don't keep re-reading it. In theory
  46          * we could cache it forever as nobody else should be writing it.
  47          */
  48         u8 cached_hyst;
  49         unsigned long hyst_valid;
  50 };
  51
  52 static ssize_t show_temp(struct device *dev,
  53                         struct device_attribute *attr, char *buf)
  54 {
  55         struct i2c_client *client = to_i2c_client(dev);
  56         struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
  57         int retval = i2c_smbus_read_byte_data(client, sda->index);
  58
  59         if (retval < 0)
  60                 return retval;
  61         return sprintf(buf, "%d000\n", retval);
  62 }
  63
  64 static ssize_t show_bit(struct device *dev,
  65                         struct device_attribute *attr, char *buf)
  66 {
  67         struct i2c_client *client = to_i2c_client(dev);
  68         struct sensor_device_attribute_2 *sda = to_sensor_dev_attr_2(attr);
  69         int retval = i2c_smbus_read_byte_data(client, sda->nr);
  70
  71         if (retval < 0)
  72                 return retval;
  73         retval &= sda->index;
  74         return sprintf(buf, "%d\n", retval ? 1 : 0);
  75 }
  76
  77 static ssize_t store_temp(struct device *dev,
  78                 struct device_attribute *attr, const char *buf, size_t count)
  79 {
  80         struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
  81         struct i2c_client *client = to_i2c_client(dev);
  82         unsigned long val;
  83         int retval;
  84
  85         if (kstrtoul(buf, 10, &val))
  86                 return -EINVAL;
  87         retval = i2c_smbus_write_byte_data(client, sda->index,
  88                                         DIV_ROUND_CLOSEST(val, 1000));
  89         if (retval < 0)
  90                 return retval;
  91         return count;
  92 }
  93
  94 static ssize_t store_bit(struct device *dev,
  95                 struct device_attribute *attr, const char *buf, size_t count)
  96 {
  97         struct i2c_client *client = to_i2c_client(dev);
  98         struct thermal_data *data = i2c_get_clientdata(client);
  99         struct sensor_device_attribute_2 *sda = to_sensor_dev_attr_2(attr);
 100         unsigned long val;
 101         int retval;
 102
 103         if (kstrtoul(buf, 10, &val))
 104                 return -EINVAL;
 105
 106         mutex_lock(&data->mutex);
 107         retval = i2c_smbus_read_byte_data(client, sda->nr);
 108         if (retval < 0)
 109                 goto fail;
 110
 111         retval &= ~sda->index;
 112         if (val)
 113                 retval |= sda->index;
 114
 115         retval = i2c_smbus_write_byte_data(client, sda->index, retval);
 116         if (retval == 0)
 117                 retval = count;
 118 fail:
 119         mutex_unlock(&data->mutex);
 120         return retval;
 121 }
 122
 123 static ssize_t show_hyst(struct device *dev,
 124                         struct device_attribute *attr, char *buf)
 125 {
 126         struct i2c_client *client = to_i2c_client(dev);
 127         struct thermal_data *data = i2c_get_clientdata(client);
 128         struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
 129         int retval;
 130         int hyst;
 131
 132         retval = i2c_smbus_read_byte_data(client, sda->index);
 133         if (retval < 0)
 134                 return retval;
 135
 136         if (time_after(jiffies, data->hyst_valid)) {
 137                 hyst = i2c_smbus_read_byte_data(client, 0x21);
 138                 if (hyst < 0)
 139                         return retval;
 140                 data->cached_hyst = hyst;
 141                 data->hyst_valid = jiffies + HZ;
 142         }
 143         return sprintf(buf, "%d000\n", retval - data->cached_hyst);
 144 }
 145
 146 static ssize_t store_hyst(struct device *dev,
 147                 struct device_attribute *attr, const char *buf, size_t count)
 148 {
 149         struct i2c_client *client = to_i2c_client(dev);
 150         struct thermal_data *data = i2c_get_clientdata(client);
 151         struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
 152         int retval;
 153         int hyst;
 154         unsigned long val;
 155
 156         if (kstrtoul(buf, 10, &val))
 157                 return -EINVAL;
 158
 159         mutex_lock(&data->mutex);
 160         retval = i2c_smbus_read_byte_data(client, sda->index);
 161         if (retval < 0)
 162                 goto fail;
 163
 164         hyst = retval * 1000 - val;
 165         hyst = DIV_ROUND_CLOSEST(hyst, 1000);
 166         if (hyst < 0 || hyst > 255) {
 167                 retval = -ERANGE;
 168                 goto fail;
 169         }
 170
 171         retval = i2c_smbus_write_byte_data(client, 0x21, hyst);
 172         if (retval == 0) {
 173                 retval = count;
 174                 data->cached_hyst = hyst;
 175                 data->hyst_valid = jiffies + HZ;
 176         }
 177 fail:
 178         mutex_unlock(&data->mutex);
 179         return retval;
 180 }
 181
 182 /*
 183  *      Sensors. We pass the actual i2c register to the methods.
 184  */
 185
 186 static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO | S_IWUSR,
 187         show_temp, store_temp, 0x06);
 188 static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO | S_IWUSR,
 189         show_temp, store_temp, 0x05);
 190 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO | S_IWUSR,
 191         show_temp, store_temp, 0x20);
 192 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0x00);
 193 static SENSOR_DEVICE_ATTR_2(temp1_min_alarm, S_IRUGO,
 194         show_bit, NULL, 0x36, 0x01);
 195 static SENSOR_DEVICE_ATTR_2(temp1_max_alarm, S_IRUGO,
 196         show_bit, NULL, 0x35, 0x01);
 197 static SENSOR_DEVICE_ATTR_2(temp1_crit_alarm, S_IRUGO,
 198         show_bit, NULL, 0x37, 0x01);
 199 static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IRUGO | S_IWUSR,
 200         show_hyst, store_hyst, 0x20);
 201
 202 static SENSOR_DEVICE_ATTR(temp2_min, S_IRUGO | S_IWUSR,
 203         show_temp, store_temp, 0x08);
 204 static SENSOR_DEVICE_ATTR(temp2_max, S_IRUGO | S_IWUSR,
 205         show_temp, store_temp, 0x07);
 206 static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO | S_IWUSR,
 207         show_temp, store_temp, 0x19);
 208 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 0x01);
 209 static SENSOR_DEVICE_ATTR_2(temp2_min_alarm, S_IRUGO,
 210         show_bit, NULL, 0x36, 0x02);
 211 static SENSOR_DEVICE_ATTR_2(temp2_max_alarm, S_IRUGO,
 212         show_bit, NULL, 0x35, 0x02);
 213 static SENSOR_DEVICE_ATTR_2(temp2_crit_alarm, S_IRUGO,
 214         show_bit, NULL, 0x37, 0x02);
 215 static SENSOR_DEVICE_ATTR(temp2_crit_hyst, S_IRUGO | S_IWUSR,
 216         show_hyst, store_hyst, 0x19);
 217
 218 static SENSOR_DEVICE_ATTR(temp3_min, S_IRUGO | S_IWUSR,
 219         show_temp, store_temp, 0x16);
 220 static SENSOR_DEVICE_ATTR(temp3_max, S_IRUGO | S_IWUSR,
 221         show_temp, store_temp, 0x15);
 222 static SENSOR_DEVICE_ATTR(temp3_crit, S_IRUGO | S_IWUSR,
 223         show_temp, store_temp, 0x1A);
 224 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 0x23);
 225 static SENSOR_DEVICE_ATTR_2(temp3_min_alarm, S_IRUGO,
 226         show_bit, NULL, 0x36, 0x04);
 227 static SENSOR_DEVICE_ATTR_2(temp3_max_alarm, S_IRUGO,
 228         show_bit, NULL, 0x35, 0x04);
 229 static SENSOR_DEVICE_ATTR_2(temp3_crit_alarm, S_IRUGO,
 230         show_bit, NULL, 0x37, 0x04);
 231 static SENSOR_DEVICE_ATTR(temp3_crit_hyst, S_IRUGO | S_IWUSR,
 232         show_hyst, store_hyst, 0x1A);
 233
 234 static SENSOR_DEVICE_ATTR_2(power_state, S_IRUGO | S_IWUSR,
 235         show_bit, store_bit, 0x03, 0x40);
 236
 237 static struct attribute *mid_att_thermal[] = {
 238         &sensor_dev_attr_temp1_min.dev_attr.attr,
 239         &sensor_dev_attr_temp1_max.dev_attr.attr,
 240         &sensor_dev_attr_temp1_crit.dev_attr.attr,
 241         &sensor_dev_attr_temp1_input.dev_attr.attr,
 242         &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
 243         &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 244         &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
 245         &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr,
 246         &sensor_dev_attr_temp2_min.dev_attr.attr,
 247         &sensor_dev_attr_temp2_max.dev_attr.attr,
 248         &sensor_dev_attr_temp2_crit.dev_attr.attr,
 249         &sensor_dev_attr_temp2_input.dev_attr.attr,
 250         &sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
 251         &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
 252         &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
 253         &sensor_dev_attr_temp2_crit_hyst.dev_attr.attr,
 254         &sensor_dev_attr_temp3_min.dev_attr.attr,
 255         &sensor_dev_attr_temp3_max.dev_attr.attr,
 256         &sensor_dev_attr_temp3_crit.dev_attr.attr,
 257         &sensor_dev_attr_temp3_input.dev_attr.attr,
 258         &sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
 259         &sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
 260         &sensor_dev_attr_temp3_crit_alarm.dev_attr.attr,
 261         &sensor_dev_attr_temp3_crit_hyst.dev_attr.attr,
 262         &sensor_dev_attr_power_state.dev_attr.attr,
 263         NULL
 264 };
 265
 266 static const struct attribute_group m_thermal_gr = {
 267         .attrs = mid_att_thermal
 268 };
 269
 270 static int emc1403_detect(struct i2c_client *client,
 271                         struct i2c_board_info *info)
 272 {
 273         int id;
 274         /* Check if thermal chip is SMSC and EMC1403 or EMC1423 */
 275
 276         id = i2c_smbus_read_byte_data(client, THERMAL_SMSC_ID_REG);
 277         if (id != 0x5d)
 278                 return -ENODEV;
 279
 280         id = i2c_smbus_read_byte_data(client, THERMAL_PID_REG);
 281         switch (id) {
 282         case 0x21:
 283                 strlcpy(info->type, "emc1403", I2C_NAME_SIZE);
 284                 break;
 285         case 0x23:
 286                 strlcpy(info->type, "emc1423", I2C_NAME_SIZE);
 287                 break;
 288         /*
 289          * Note: 0x25 is the 1404 which is very similar and this
 290          * driver could be extended
 291          */
 292         default:
 293                 return -ENODEV;
 294         }
 295
 296         id = i2c_smbus_read_byte_data(client, THERMAL_REVISION_REG);
 297         if (id < 0x01 || id > 0x04)
 298                 return -ENODEV;
 299
 300         return 0;
 301 }
 302
 303 static int emc1403_probe(struct i2c_client *client,
 304                         const struct i2c_device_id *id)
 305 {
 306         int res;
 307         struct thermal_data *data;
 308
 309         data = kzalloc(sizeof(struct thermal_data), GFP_KERNEL);
 310         if (data == NULL) {
 311                 dev_warn(&client->dev, "out of memory");
 312                 return -ENOMEM;
 313         }
 314
 315         i2c_set_clientdata(client, data);
 316         mutex_init(&data->mutex);
 317         data->hyst_valid = jiffies - 1;         /* Expired */
 318
 319         res = sysfs_create_group(&client->dev.kobj, &m_thermal_gr);
 320         if (res) {
 321                 dev_warn(&client->dev, "create group failed\n");
 322                 goto thermal_error1;
 323         }
 324         data->hwmon_dev = hwmon_device_register(&client->dev);
 325         if (IS_ERR(data->hwmon_dev)) {
 326                 res = PTR_ERR(data->hwmon_dev);
 327                 dev_warn(&client->dev, "register hwmon dev failed\n");
 328                 goto thermal_error2;
 329         }
 330         dev_info(&client->dev, "EMC1403 Thermal chip found\n");
 331         return res;
 332
 333 thermal_error2:
 334         sysfs_remove_group(&client->dev.kobj, &m_thermal_gr);
 335 thermal_error1:
 336         kfree(data);
 337         return res;
 338 }
 339
 340 static int emc1403_remove(struct i2c_client *client)
 341 {
 342         struct thermal_data *data = i2c_get_clientdata(client);
 343
 344         hwmon_device_unregister(data->hwmon_dev);
 345         sysfs_remove_group(&client->dev.kobj, &m_thermal_gr);
 346         kfree(data);
 347         return 0;
 348 }
 349
 350 static const unsigned short emc1403_address_list[] = {
 351         0x18, 0x29, 0x4c, 0x4d, I2C_CLIENT_END
 352 };
 353
 354 static const struct i2c_device_id emc1403_idtable[] = {
 355         { "emc1403", 0 },
 356         { "emc1423", 0 },
 357         { }
 358 };
 359 MODULE_DEVICE_TABLE(i2c, emc1403_idtable);
 360
 361 static struct i2c_driver sensor_emc1403 = {
 362         .class = I2C_CLASS_HWMON,
 363         .driver = {
 364                 .name = "emc1403",
 365         },
 366         .detect = emc1403_detect,
 367         .probe = emc1403_probe,
 368         .remove = emc1403_remove,
 369         .id_table = emc1403_idtable,
 370         .address_list = emc1403_address_list,
 371 };
 372
 373 module_i2c_driver(sensor_emc1403);
 374
 375 MODULE_AUTHOR("Kalhan Trisal <kalhan.trisal@intel.com");
 376 MODULE_DESCRIPTION("emc1403 Thermal Driver");
 377 MODULE_LICENSE("GPL v2");