1/* 2 * acpi_fan.c - ACPI Fan Driver ($Revision: 29 $) 3 * 4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> 5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 6 * 7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; either version 2 of the License, or (at 12 * your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, but 15 * WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License along 20 * with this program; if not, write to the Free Software Foundation, Inc., 21 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. 22 * 23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 24 */ 25 26#include <linux/kernel.h> 27#include <linux/module.h> 28#include <linux/init.h> 29#include <linux/types.h> 30#include <linux/proc_fs.h> 31#include <linux/seq_file.h> 32#include <asm/uaccess.h> 33#include <linux/thermal.h> 34#include <acpi/acpi_bus.h> 35#include <acpi/acpi_drivers.h> 36 37#define PREFIX "ACPI: " 38 39#define ACPI_FAN_CLASS "fan" 40#define ACPI_FAN_FILE_STATE "state" 41 42#define _COMPONENT ACPI_FAN_COMPONENT 43ACPI_MODULE_NAME("fan"); 44 45MODULE_AUTHOR("Paul Diefenbaugh"); 46MODULE_DESCRIPTION("ACPI Fan Driver"); 47MODULE_LICENSE("GPL"); 48 49static int acpi_fan_add(struct acpi_device *device); 50static int acpi_fan_remove(struct acpi_device *device, int type); 51static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state); 52static int acpi_fan_resume(struct acpi_device *device); 53 54static const struct acpi_device_id fan_device_ids[] = { 55 {"PNP0C0B", 0}, 56 {"", 0}, 57}; 58MODULE_DEVICE_TABLE(acpi, fan_device_ids); 59 60static struct acpi_driver acpi_fan_driver = { 61 .name = "fan", 62 .class = ACPI_FAN_CLASS, 63 .ids = fan_device_ids, 64 .ops = { 65 .add = acpi_fan_add, 66 .remove = acpi_fan_remove, 67 .suspend = acpi_fan_suspend, 68 .resume = acpi_fan_resume, 69 }, 70}; 71 72/* thermal cooling device callbacks */ 73static int fan_get_max_state(struct thermal_cooling_device *cdev, unsigned long 74 *state) 75{ 76 /* ACPI fan device only support two states: ON/OFF */ 77 *state = 1; 78 return 0; 79} 80 81static int fan_get_cur_state(struct thermal_cooling_device *cdev, unsigned long 82 *state) 83{ 84 struct acpi_device *device = cdev->devdata; 85 int result; 86 int acpi_state; 87 88 if (!device) 89 return -EINVAL; 90 91 result = acpi_bus_get_power(device->handle, &acpi_state); 92 if (result) 93 return result; 94 95 *state = (acpi_state == ACPI_STATE_D3 ? 0 : 96 (acpi_state == ACPI_STATE_D0 ? 1 : -1)); 97 return 0; 98} 99 100static int 101fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state) 102{ 103 struct acpi_device *device = cdev->devdata; 104 int result; 105 106 if (!device || (state != 0 && state != 1)) 107 return -EINVAL; 108 109 result = acpi_bus_set_power(device->handle, 110 state ? ACPI_STATE_D0 : ACPI_STATE_D3); 111 112 return result; 113} 114 115static struct thermal_cooling_device_ops fan_cooling_ops = { 116 .get_max_state = fan_get_max_state, 117 .get_cur_state = fan_get_cur_state, 118 .set_cur_state = fan_set_cur_state, 119}; 120 121/* -------------------------------------------------------------------------- 122 FS Interface (/proc) 123 -------------------------------------------------------------------------- */ 124#ifdef CONFIG_ACPI_PROCFS 125 126static struct proc_dir_entry *acpi_fan_dir; 127 128static int acpi_fan_read_state(struct seq_file *seq, void *offset) 129{ 130 struct acpi_device *device = seq->private; 131 int state = 0; 132 133 134 if (device) { 135 if (acpi_bus_get_power(device->handle, &state)) 136 seq_printf(seq, "status: ERROR\n"); 137 else 138 seq_printf(seq, "status: %s\n", 139 !state ? "on" : "off"); 140 } 141 return 0; 142} 143 144static int acpi_fan_state_open_fs(struct inode *inode, struct file *file) 145{ 146 return single_open(file, acpi_fan_read_state, PDE(inode)->data); 147} 148 149static ssize_t 150acpi_fan_write_state(struct file *file, const char __user * buffer, 151 size_t count, loff_t * ppos) 152{ 153 int result = 0; 154 struct seq_file *m = file->private_data; 155 struct acpi_device *device = m->private; 156 char state_string[3] = { '\0' }; 157 158 if (count > sizeof(state_string) - 1) 159 return -EINVAL; 160 161 if (copy_from_user(state_string, buffer, count)) 162 return -EFAULT; 163 164 state_string[count] = '\0'; 165 if ((state_string[0] < '0') || (state_string[0] > '3')) 166 return -EINVAL; 167 if (state_string[1] == '\n') 168 state_string[1] = '\0'; 169 if (state_string[1] != '\0') 170 return -EINVAL; 171 172 result = acpi_bus_set_power(device->handle, 173 simple_strtoul(state_string, NULL, 0)); 174 if (result) 175 return result; 176 177 return count; 178} 179 180static const struct file_operations acpi_fan_state_ops = { 181 .open = acpi_fan_state_open_fs, 182 .read = seq_read, 183 .write = acpi_fan_write_state, 184 .llseek = seq_lseek, 185 .release = single_release, 186 .owner = THIS_MODULE, 187}; 188 189static int acpi_fan_add_fs(struct acpi_device *device) 190{ 191 struct proc_dir_entry *entry = NULL; 192 193 194 if (!device) 195 return -EINVAL; 196 197 if (!acpi_device_dir(device)) { 198 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device), 199 acpi_fan_dir); 200 if (!acpi_device_dir(device)) 201 return -ENODEV; 202 } 203 204 /* 'status' [R/W] */ 205 entry = proc_create_data(ACPI_FAN_FILE_STATE, 206 S_IFREG | S_IRUGO | S_IWUSR, 207 acpi_device_dir(device), 208 &acpi_fan_state_ops, 209 device); 210 if (!entry) 211 return -ENODEV; 212 return 0; 213} 214 215static int acpi_fan_remove_fs(struct acpi_device *device) 216{ 217 218 if (acpi_device_dir(device)) { 219 remove_proc_entry(ACPI_FAN_FILE_STATE, acpi_device_dir(device)); 220 remove_proc_entry(acpi_device_bid(device), acpi_fan_dir); 221 acpi_device_dir(device) = NULL; 222 } 223 224 return 0; 225} 226#else 227static int acpi_fan_add_fs(struct acpi_device *device) 228{ 229 return 0; 230} 231 232static int acpi_fan_remove_fs(struct acpi_device *device) 233{ 234 return 0; 235} 236#endif 237/* -------------------------------------------------------------------------- 238 Driver Interface 239 -------------------------------------------------------------------------- */ 240 241static int acpi_fan_add(struct acpi_device *device) 242{ 243 int result = 0; 244 int state = 0; 245 struct thermal_cooling_device *cdev; 246 247 if (!device) 248 return -EINVAL; 249 250 strcpy(acpi_device_name(device), "Fan"); 251 strcpy(acpi_device_class(device), ACPI_FAN_CLASS); 252 253 result = acpi_bus_get_power(device->handle, &state); 254 if (result) { 255 printk(KERN_ERR PREFIX "Reading power state\n"); 256 goto end; 257 } 258 259 device->flags.force_power_state = 1; 260 acpi_bus_set_power(device->handle, state); 261 device->flags.force_power_state = 0; 262 263 cdev = thermal_cooling_device_register("Fan", device, 264 &fan_cooling_ops); 265 if (IS_ERR(cdev)) { 266 result = PTR_ERR(cdev); 267 goto end; 268 } 269 270 dev_dbg(&device->dev, "registered as cooling_device%d\n", cdev->id); 271 272 device->driver_data = cdev; 273 result = sysfs_create_link(&device->dev.kobj, 274 &cdev->device.kobj, 275 "thermal_cooling"); 276 if (result) 277 dev_err(&device->dev, "Failed to create sysfs link " 278 "'thermal_cooling'\n"); 279 280 result = sysfs_create_link(&cdev->device.kobj, 281 &device->dev.kobj, 282 "device"); 283 if (result) 284 dev_err(&device->dev, "Failed to create sysfs link " 285 "'device'\n"); 286 287 result = acpi_fan_add_fs(device); 288 if (result) 289 goto end; 290 291 printk(KERN_INFO PREFIX "%s [%s] (%s)\n", 292 acpi_device_name(device), acpi_device_bid(device), 293 !device->power.state ? "on" : "off"); 294 295 end: 296 return result; 297} 298 299static int acpi_fan_remove(struct acpi_device *device, int type) 300{ 301 struct thermal_cooling_device *cdev = acpi_driver_data(device); 302 303 if (!device || !cdev) 304 return -EINVAL; 305 306 acpi_fan_remove_fs(device); 307 sysfs_remove_link(&device->dev.kobj, "thermal_cooling"); 308 sysfs_remove_link(&cdev->device.kobj, "device"); 309 thermal_cooling_device_unregister(cdev); 310 311 return 0; 312} 313 314static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state) 315{ 316 if (!device) 317 return -EINVAL; 318 319 acpi_bus_set_power(device->handle, ACPI_STATE_D0); 320 321 return AE_OK; 322} 323 324static int acpi_fan_resume(struct acpi_device *device) 325{ 326 int result = 0; 327 int power_state = 0; 328 329 if (!device) 330 return -EINVAL; 331 332 result = acpi_bus_get_power(device->handle, &power_state); 333 if (result) { 334 printk(KERN_ERR PREFIX 335 "Error reading fan power state\n"); 336 return result; 337 } 338 339 device->flags.force_power_state = 1; 340 acpi_bus_set_power(device->handle, power_state); 341 device->flags.force_power_state = 0; 342 343 return result; 344} 345 346static int __init acpi_fan_init(void) 347{ 348 int result = 0; 349 350#ifdef CONFIG_ACPI_PROCFS 351 acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir); 352 if (!acpi_fan_dir) 353 return -ENODEV; 354#endif 355 356 result = acpi_bus_register_driver(&acpi_fan_driver); 357 if (result < 0) { 358#ifdef CONFIG_ACPI_PROCFS 359 remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir); 360#endif 361 return -ENODEV; 362 } 363 364 return 0; 365} 366 367static void __exit acpi_fan_exit(void) 368{ 369 370 acpi_bus_unregister_driver(&acpi_fan_driver); 371 372#ifdef CONFIG_ACPI_PROCFS 373 remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir); 374#endif 375 376 return; 377} 378 379module_init(acpi_fan_init); 380module_exit(acpi_fan_exit); 381