drivers/pnp/driver.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * driver.c - device id matching, driver model, etc.
   4  *
   5  * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
   6  */
   7
   8 #include <linux/string.h>
   9 #include <linux/list.h>
  10 #include <linux/module.h>
  11 #include <linux/ctype.h>
  12 #include <linux/slab.h>
  13 #include <linux/pnp.h>
  14 #include "base.h"
  15
  16 static int compare_func(const char *ida, const char *idb)
  17 {
  18         int i;
  19
  20         /* we only need to compare the last 4 chars */
  21         for (i = 3; i < 7; i++) {
  22                 if (ida[i] != 'X' &&
  23                     idb[i] != 'X' && toupper(ida[i]) != toupper(idb[i]))
  24                         return 0;
  25         }
  26         return 1;
  27 }
  28
  29 int compare_pnp_id(struct pnp_id *pos, const char *id)
  30 {
  31         if (!pos || !id || (strlen(id) != 7))
  32                 return 0;
  33         if (memcmp(id, "ANYDEVS", 7) == 0)
  34                 return 1;
  35         while (pos) {
  36                 if (memcmp(pos->id, id, 3) == 0)
  37                         if (compare_func(pos->id, id) == 1)
  38                                 return 1;
  39                 pos = pos->next;
  40         }
  41         return 0;
  42 }
  43
  44 static const struct pnp_device_id *match_device(const struct pnp_driver *drv,
  45                                                 struct pnp_dev *dev)
  46 {
  47         const struct pnp_device_id *drv_id = drv->id_table;
  48
  49         if (!drv_id)
  50                 return NULL;
  51
  52         while (*drv_id->id) {
  53                 if (compare_pnp_id(dev->id, drv_id->id))
  54                         return drv_id;
  55                 drv_id++;
  56         }
  57         return NULL;
  58 }
  59
  60 int pnp_device_attach(struct pnp_dev *pnp_dev)
  61 {
  62         mutex_lock(&pnp_lock);
  63         if (pnp_dev->status != PNP_READY) {
  64                 mutex_unlock(&pnp_lock);
  65                 return -EBUSY;
  66         }
  67         pnp_dev->status = PNP_ATTACHED;
  68         mutex_unlock(&pnp_lock);
  69         return 0;
  70 }
  71 EXPORT_SYMBOL(pnp_device_attach);
  72
  73 void pnp_device_detach(struct pnp_dev *pnp_dev)
  74 {
  75         mutex_lock(&pnp_lock);
  76         if (pnp_dev->status == PNP_ATTACHED)
  77                 pnp_dev->status = PNP_READY;
  78         mutex_unlock(&pnp_lock);
  79 }
  80 EXPORT_SYMBOL(pnp_device_detach);
  81
  82 static int pnp_device_probe(struct device *dev)
  83 {
  84         int error;
  85         struct pnp_driver *pnp_drv;
  86         struct pnp_dev *pnp_dev;
  87         const struct pnp_device_id *dev_id = NULL;
  88         pnp_dev = to_pnp_dev(dev);
  89         pnp_drv = to_pnp_driver(dev->driver);
  90
  91         error = pnp_device_attach(pnp_dev);
  92         if (error < 0)
  93                 return error;
  94
  95         if (pnp_dev->active == 0) {
  96                 if (!(pnp_drv->flags & PNP_DRIVER_RES_DO_NOT_CHANGE)) {
  97                         error = pnp_activate_dev(pnp_dev);
  98                         if (error < 0)
  99                                 return error;
 100                 }
 101         } else if ((pnp_drv->flags & PNP_DRIVER_RES_DISABLE)
 102                    == PNP_DRIVER_RES_DISABLE) {
 103                 error = pnp_disable_dev(pnp_dev);
 104                 if (error < 0)
 105                         return error;
 106         }
 107         error = 0;
 108         if (pnp_drv->probe) {
 109                 dev_id = match_device(pnp_drv, pnp_dev);
 110                 if (dev_id != NULL)
 111                         error = pnp_drv->probe(pnp_dev, dev_id);
 112         }
 113         if (error >= 0) {
 114                 pnp_dev->driver = pnp_drv;
 115                 error = 0;
 116         } else
 117                 goto fail;
 118
 119         return error;
 120
 121 fail:
 122         pnp_device_detach(pnp_dev);
 123         return error;
 124 }
 125
 126 static void pnp_device_remove(struct device *dev)
 127 {
 128         struct pnp_dev *pnp_dev = to_pnp_dev(dev);
 129         struct pnp_driver *drv = pnp_dev->driver;
 130
 131         if (drv) {
 132                 if (drv->remove)
 133                         drv->remove(pnp_dev);
 134                 pnp_dev->driver = NULL;
 135         }
 136
 137         if (pnp_dev->active &&
 138             (!drv || !(drv->flags & PNP_DRIVER_RES_DO_NOT_CHANGE)))
 139                 pnp_disable_dev(pnp_dev);
 140
 141         pnp_device_detach(pnp_dev);
 142 }
 143
 144 static void pnp_device_shutdown(struct device *dev)
 145 {
 146         struct pnp_dev *pnp_dev = to_pnp_dev(dev);
 147         struct pnp_driver *drv = pnp_dev->driver;
 148
 149         if (drv && drv->shutdown)
 150                 drv->shutdown(pnp_dev);
 151 }
 152
 153 static int pnp_bus_match(struct device *dev, const struct device_driver *drv)
 154 {
 155         struct pnp_dev *pnp_dev = to_pnp_dev(dev);
 156         const struct pnp_driver *pnp_drv = to_pnp_driver(drv);
 157
 158         if (match_device(pnp_drv, pnp_dev) == NULL)
 159                 return 0;
 160         return 1;
 161 }
 162
 163 static int __pnp_bus_suspend(struct device *dev, pm_message_t state)
 164 {
 165         struct pnp_dev *pnp_dev = to_pnp_dev(dev);
 166         struct pnp_driver *pnp_drv = pnp_dev->driver;
 167         int error;
 168
 169         if (!pnp_drv)
 170                 return 0;
 171
 172         if (pnp_drv->driver.pm && pnp_drv->driver.pm->suspend) {
 173                 error = pnp_drv->driver.pm->suspend(dev);
 174                 suspend_report_result(dev, pnp_drv->driver.pm->suspend, error);
 175                 if (error)
 176                         return error;
 177         }
 178
 179         if (pnp_drv->suspend) {
 180                 error = pnp_drv->suspend(pnp_dev, state);
 181                 if (error)
 182                         return error;
 183         }
 184
 185         /* can_write is necessary to be able to re-start the device on resume */
 186         if (pnp_can_disable(pnp_dev) && pnp_can_write(pnp_dev)) {
 187                 error = pnp_stop_dev(pnp_dev);
 188                 if (error)
 189                         return error;
 190         }
 191
 192         if (pnp_can_suspend(pnp_dev))
 193                 pnp_dev->protocol->suspend(pnp_dev, state);
 194         return 0;
 195 }
 196
 197 static int pnp_bus_suspend(struct device *dev)
 198 {
 199         return __pnp_bus_suspend(dev, PMSG_SUSPEND);
 200 }
 201
 202 static int pnp_bus_freeze(struct device *dev)
 203 {
 204         return __pnp_bus_suspend(dev, PMSG_FREEZE);
 205 }
 206
 207 static int pnp_bus_poweroff(struct device *dev)
 208 {
 209         return __pnp_bus_suspend(dev, PMSG_HIBERNATE);
 210 }
 211
 212 static int pnp_bus_resume(struct device *dev)
 213 {
 214         struct pnp_dev *pnp_dev = to_pnp_dev(dev);
 215         struct pnp_driver *pnp_drv = pnp_dev->driver;
 216         int error;
 217
 218         if (!pnp_drv)
 219                 return 0;
 220
 221         if (pnp_dev->protocol->resume) {
 222                 error = pnp_dev->protocol->resume(pnp_dev);
 223                 if (error)
 224                         return error;
 225         }
 226
 227         if (pnp_can_write(pnp_dev)) {
 228                 error = pnp_start_dev(pnp_dev);
 229                 if (error)
 230                         return error;
 231         }
 232
 233         if (pnp_drv->driver.pm && pnp_drv->driver.pm->resume) {
 234                 error = pnp_drv->driver.pm->resume(dev);
 235                 if (error)
 236                         return error;
 237         }
 238
 239         if (pnp_drv->resume) {
 240                 error = pnp_drv->resume(pnp_dev);
 241                 if (error)
 242                         return error;
 243         }
 244
 245         return 0;
 246 }
 247
 248 static const struct dev_pm_ops pnp_bus_dev_pm_ops = {
 249         /* Suspend callbacks */
 250         .suspend = pnp_bus_suspend,
 251         .resume = pnp_bus_resume,
 252         /* Hibernate callbacks */
 253         .freeze = pnp_bus_freeze,
 254         .thaw = pnp_bus_resume,
 255         .poweroff = pnp_bus_poweroff,
 256         .restore = pnp_bus_resume,
 257 };
 258
 259 const struct bus_type pnp_bus_type = {
 260         .name    = "pnp",
 261         .match   = pnp_bus_match,
 262         .probe   = pnp_device_probe,
 263         .remove  = pnp_device_remove,
 264         .shutdown = pnp_device_shutdown,
 265         .pm      = &pnp_bus_dev_pm_ops,
 266         .dev_groups = pnp_dev_groups,
 267 };
 268
 269 bool dev_is_pnp(const struct device *dev)
 270 {
 271         return dev->bus == &pnp_bus_type;
 272 }
 273 EXPORT_SYMBOL_GPL(dev_is_pnp);
 274
 275 int pnp_register_driver(struct pnp_driver *drv)
 276 {
 277         drv->driver.name = drv->name;
 278         drv->driver.bus = &pnp_bus_type;
 279
 280         return driver_register(&drv->driver);
 281 }
 282 EXPORT_SYMBOL(pnp_register_driver);
 283
 284 void pnp_unregister_driver(struct pnp_driver *drv)
 285 {
 286         driver_unregister(&drv->driver);
 287 }
 288 EXPORT_SYMBOL(pnp_unregister_driver);
 289
 290 /**
 291  * pnp_add_id - adds an EISA id to the specified device
 292  * @dev: pointer to the desired device
 293  * @id: pointer to an EISA id string
 294  */
 295 struct pnp_id *pnp_add_id(struct pnp_dev *dev, const char *id)
 296 {
 297         struct pnp_id *dev_id, *ptr;
 298
 299         dev_id = kzalloc(sizeof(struct pnp_id), GFP_KERNEL);
 300         if (!dev_id)
 301                 return NULL;
 302
 303         dev_id->id[0] = id[0];
 304         dev_id->id[1] = id[1];
 305         dev_id->id[2] = id[2];
 306         dev_id->id[3] = tolower(id[3]);
 307         dev_id->id[4] = tolower(id[4]);
 308         dev_id->id[5] = tolower(id[5]);
 309         dev_id->id[6] = tolower(id[6]);
 310         dev_id->id[7] = '\0';
 311
 312         dev_id->next = NULL;
 313         ptr = dev->id;
 314         while (ptr && ptr->next)
 315                 ptr = ptr->next;
 316         if (ptr)
 317                 ptr->next = dev_id;
 318         else
 319                 dev->id = dev_id;
 320
 321         return dev_id;
 322 }