drivers/pnp/manager.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * manager.c - Resource Management, Conflict Resolution, Activation and Disabling of Devices
   4  *
   5  * based on isapnp.c resource management (c) Jaroslav Kysela <perex@perex.cz>
   6  * Copyright 2003 Adam Belay <ambx1@neo.rr.com>
   7  * Copyright (C) 2008 Hewlett-Packard Development Company, L.P.
   8  *      Bjorn Helgaas <bjorn.helgaas@hp.com>
   9  */
  10
  11 #include <linux/errno.h>
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/kernel.h>
  15 #include <linux/pnp.h>
  16 #include <linux/bitmap.h>
  17 #include <linux/mutex.h>
  18 #include "base.h"
  19
  20 DEFINE_MUTEX(pnp_res_mutex);
  21
  22 static struct resource *pnp_find_resource(struct pnp_dev *dev,
  23                                           unsigned char rule,
  24                                           unsigned long type,
  25                                           unsigned int bar)
  26 {
  27         struct resource *res = pnp_get_resource(dev, type, bar);
  28
  29         /* when the resource already exists, set its resource bits from rule */
  30         if (res) {
  31                 res->flags &= ~IORESOURCE_BITS;
  32                 res->flags |= rule & IORESOURCE_BITS;
  33         }
  34
  35         return res;
  36 }
  37
  38 static int pnp_assign_port(struct pnp_dev *dev, struct pnp_port *rule, int idx)
  39 {
  40         struct resource *res, local_res;
  41
  42         res = pnp_find_resource(dev, rule->flags, IORESOURCE_IO, idx);
  43         if (res) {
  44                 pnp_dbg(&dev->dev, "  io %d already set to %#llx-%#llx "
  45                         "flags %#lx\n", idx, (unsigned long long) res->start,
  46                         (unsigned long long) res->end, res->flags);
  47                 return 0;
  48         }
  49
  50         res = &local_res;
  51         res->flags = rule->flags | IORESOURCE_AUTO;
  52         res->start = 0;
  53         res->end = 0;
  54
  55         if (!rule->size) {
  56                 res->flags |= IORESOURCE_DISABLED;
  57                 pnp_dbg(&dev->dev, "  io %d disabled\n", idx);
  58                 goto __add;
  59         }
  60
  61         res->start = rule->min;
  62         res->end = res->start + rule->size - 1;
  63
  64         while (!pnp_check_port(dev, res)) {
  65                 res->start += rule->align;
  66                 res->end = res->start + rule->size - 1;
  67                 if (res->start > rule->max || !rule->align) {
  68                         pnp_dbg(&dev->dev, "  couldn't assign io %d "
  69                                 "(min %#llx max %#llx)\n", idx,
  70                                 (unsigned long long) rule->min,
  71                                 (unsigned long long) rule->max);
  72                         return -EBUSY;
  73                 }
  74         }
  75
  76 __add:
  77         pnp_add_io_resource(dev, res->start, res->end, res->flags);
  78         return 0;
  79 }
  80
  81 static int pnp_assign_mem(struct pnp_dev *dev, struct pnp_mem *rule, int idx)
  82 {
  83         struct resource *res, local_res;
  84
  85         res = pnp_find_resource(dev, rule->flags, IORESOURCE_MEM, idx);
  86         if (res) {
  87                 pnp_dbg(&dev->dev, "  mem %d already set to %#llx-%#llx "
  88                         "flags %#lx\n", idx, (unsigned long long) res->start,
  89                         (unsigned long long) res->end, res->flags);
  90                 return 0;
  91         }
  92
  93         res = &local_res;
  94         res->flags = rule->flags | IORESOURCE_AUTO;
  95         res->start = 0;
  96         res->end = 0;
  97
  98         /* ??? rule->flags restricted to 8 bits, all tests bogus ??? */
  99         if (!(rule->flags & IORESOURCE_MEM_WRITEABLE))
 100                 res->flags |= IORESOURCE_READONLY;
 101         if (rule->flags & IORESOURCE_MEM_RANGELENGTH)
 102                 res->flags |= IORESOURCE_RANGELENGTH;
 103         if (rule->flags & IORESOURCE_MEM_SHADOWABLE)
 104                 res->flags |= IORESOURCE_SHADOWABLE;
 105
 106         if (!rule->size) {
 107                 res->flags |= IORESOURCE_DISABLED;
 108                 pnp_dbg(&dev->dev, "  mem %d disabled\n", idx);
 109                 goto __add;
 110         }
 111
 112         res->start = rule->min;
 113         res->end = res->start + rule->size - 1;
 114
 115         while (!pnp_check_mem(dev, res)) {
 116                 res->start += rule->align;
 117                 res->end = res->start + rule->size - 1;
 118                 if (res->start > rule->max || !rule->align) {
 119                         pnp_dbg(&dev->dev, "  couldn't assign mem %d "
 120                                 "(min %#llx max %#llx)\n", idx,
 121                                 (unsigned long long) rule->min,
 122                                 (unsigned long long) rule->max);
 123                         return -EBUSY;
 124                 }
 125         }
 126
 127 __add:
 128         pnp_add_mem_resource(dev, res->start, res->end, res->flags);
 129         return 0;
 130 }
 131
 132 static int pnp_assign_irq(struct pnp_dev *dev, struct pnp_irq *rule, int idx)
 133 {
 134         struct resource *res, local_res;
 135         int i;
 136
 137         /* IRQ priority: this table is good for i386 */
 138         static unsigned short xtab[16] = {
 139                 5, 10, 11, 12, 9, 14, 15, 7, 3, 4, 13, 0, 1, 6, 8, 2
 140         };
 141
 142         res = pnp_find_resource(dev, rule->flags, IORESOURCE_IRQ, idx);
 143         if (res) {
 144                 pnp_dbg(&dev->dev, "  irq %d already set to %d flags %#lx\n",
 145                         idx, (int) res->start, res->flags);
 146                 return 0;
 147         }
 148
 149         res = &local_res;
 150         res->flags = rule->flags | IORESOURCE_AUTO;
 151         res->start = -1;
 152         res->end = -1;
 153
 154         if (bitmap_empty(rule->map.bits, PNP_IRQ_NR)) {
 155                 res->flags |= IORESOURCE_DISABLED;
 156                 pnp_dbg(&dev->dev, "  irq %d disabled\n", idx);
 157                 goto __add;
 158         }
 159
 160         /* TBD: need check for >16 IRQ */
 161         res->start = find_next_bit(rule->map.bits, PNP_IRQ_NR, 16);
 162         if (res->start < PNP_IRQ_NR) {
 163                 res->end = res->start;
 164                 goto __add;
 165         }
 166         for (i = 0; i < 16; i++) {
 167                 if (test_bit(xtab[i], rule->map.bits)) {
 168                         res->start = res->end = xtab[i];
 169                         if (pnp_check_irq(dev, res))
 170                                 goto __add;
 171                 }
 172         }
 173
 174         if (rule->flags & IORESOURCE_IRQ_OPTIONAL) {
 175                 res->start = -1;
 176                 res->end = -1;
 177                 res->flags |= IORESOURCE_DISABLED;
 178                 pnp_dbg(&dev->dev, "  irq %d disabled (optional)\n", idx);
 179                 goto __add;
 180         }
 181
 182         pnp_dbg(&dev->dev, "  couldn't assign irq %d\n", idx);
 183         return -EBUSY;
 184
 185 __add:
 186         pnp_add_irq_resource(dev, res->start, res->flags);
 187         return 0;
 188 }
 189
 190 #ifdef CONFIG_ISA_DMA_API
 191 static int pnp_assign_dma(struct pnp_dev *dev, struct pnp_dma *rule, int idx)
 192 {
 193         struct resource *res, local_res;
 194         int i;
 195
 196         /* DMA priority: this table is good for i386 */
 197         static unsigned short xtab[8] = {
 198                 1, 3, 5, 6, 7, 0, 2, 4
 199         };
 200
 201         res = pnp_find_resource(dev, rule->flags, IORESOURCE_DMA, idx);
 202         if (res) {
 203                 pnp_dbg(&dev->dev, "  dma %d already set to %d flags %#lx\n",
 204                         idx, (int) res->start, res->flags);
 205                 return 0;
 206         }
 207
 208         res = &local_res;
 209         res->flags = rule->flags | IORESOURCE_AUTO;
 210         res->start = -1;
 211         res->end = -1;
 212
 213         if (!rule->map) {
 214                 res->flags |= IORESOURCE_DISABLED;
 215                 pnp_dbg(&dev->dev, "  dma %d disabled\n", idx);
 216                 goto __add;
 217         }
 218
 219         for (i = 0; i < 8; i++) {
 220                 if (rule->map & (1 << xtab[i])) {
 221                         res->start = res->end = xtab[i];
 222                         if (pnp_check_dma(dev, res))
 223                                 goto __add;
 224                 }
 225         }
 226
 227         pnp_dbg(&dev->dev, "  couldn't assign dma %d\n", idx);
 228         return -EBUSY;
 229
 230 __add:
 231         pnp_add_dma_resource(dev, res->start, res->flags);
 232         return 0;
 233 }
 234 #endif /* CONFIG_ISA_DMA_API */
 235
 236 void pnp_init_resources(struct pnp_dev *dev)
 237 {
 238         pnp_free_resources(dev);
 239 }
 240
 241 static void pnp_clean_resource_table(struct pnp_dev *dev)
 242 {
 243         struct pnp_resource *pnp_res, *tmp;
 244
 245         list_for_each_entry_safe(pnp_res, tmp, &dev->resources, list) {
 246                 if (pnp_res->res.flags & IORESOURCE_AUTO)
 247                         pnp_free_resource(pnp_res);
 248         }
 249 }
 250
 251 /**
 252  * pnp_assign_resources - assigns resources to the device based on the specified dependent number
 253  * @dev: pointer to the desired device
 254  * @set: the dependent function number
 255  */
 256 static int pnp_assign_resources(struct pnp_dev *dev, int set)
 257 {
 258         struct pnp_option *option;
 259         int nport = 0, nmem = 0, nirq = 0;
 260         int ndma __maybe_unused = 0;
 261         int ret = 0;
 262
 263         pnp_dbg(&dev->dev, "pnp_assign_resources, try dependent set %d\n", set);
 264         mutex_lock(&pnp_res_mutex);
 265         pnp_clean_resource_table(dev);
 266
 267         list_for_each_entry(option, &dev->options, list) {
 268                 if (pnp_option_is_dependent(option) &&
 269                     pnp_option_set(option) != set)
 270                                 continue;
 271
 272                 switch (option->type) {
 273                 case IORESOURCE_IO:
 274                         ret = pnp_assign_port(dev, &option->u.port, nport++);
 275                         break;
 276                 case IORESOURCE_MEM:
 277                         ret = pnp_assign_mem(dev, &option->u.mem, nmem++);
 278                         break;
 279                 case IORESOURCE_IRQ:
 280                         ret = pnp_assign_irq(dev, &option->u.irq, nirq++);
 281                         break;
 282 #ifdef CONFIG_ISA_DMA_API
 283                 case IORESOURCE_DMA:
 284                         ret = pnp_assign_dma(dev, &option->u.dma, ndma++);
 285                         break;
 286 #endif
 287                 default:
 288                         ret = -EINVAL;
 289                         break;
 290                 }
 291                 if (ret < 0)
 292                         break;
 293         }
 294
 295         mutex_unlock(&pnp_res_mutex);
 296         if (ret < 0) {
 297                 pnp_dbg(&dev->dev, "pnp_assign_resources failed (%d)\n", ret);
 298                 pnp_clean_resource_table(dev);
 299         } else
 300                 dbg_pnp_show_resources(dev, "pnp_assign_resources succeeded");
 301         return ret;
 302 }
 303
 304 /**
 305  * pnp_auto_config_dev - automatically assigns resources to a device
 306  * @dev: pointer to the desired device
 307  */
 308 int pnp_auto_config_dev(struct pnp_dev *dev)
 309 {
 310         int i, ret;
 311
 312         if (!pnp_can_configure(dev)) {
 313                 pnp_dbg(&dev->dev, "configuration not supported\n");
 314                 return -ENODEV;
 315         }
 316
 317         ret = pnp_assign_resources(dev, 0);
 318         if (ret == 0)
 319                 return 0;
 320
 321         for (i = 1; i < dev->num_dependent_sets; i++) {
 322                 ret = pnp_assign_resources(dev, i);
 323                 if (ret == 0)
 324                         return 0;
 325         }
 326
 327         dev_err(&dev->dev, "unable to assign resources\n");
 328         return ret;
 329 }
 330
 331 /**
 332  * pnp_start_dev - low-level start of the PnP device
 333  * @dev: pointer to the desired device
 334  *
 335  * assumes that resources have already been allocated
 336  */
 337 int pnp_start_dev(struct pnp_dev *dev)
 338 {
 339         if (!pnp_can_write(dev)) {
 340                 pnp_dbg(&dev->dev, "activation not supported\n");
 341                 return -EINVAL;
 342         }
 343
 344         dbg_pnp_show_resources(dev, "pnp_start_dev");
 345         if (dev->protocol->set(dev) < 0) {
 346                 dev_err(&dev->dev, "activation failed\n");
 347                 return -EIO;
 348         }
 349
 350         dev_info(&dev->dev, "activated\n");
 351         return 0;
 352 }
 353
 354 /**
 355  * pnp_stop_dev - low-level disable of the PnP device
 356  * @dev: pointer to the desired device
 357  *
 358  * does not free resources
 359  */
 360 int pnp_stop_dev(struct pnp_dev *dev)
 361 {
 362         if (!pnp_can_disable(dev)) {
 363                 pnp_dbg(&dev->dev, "disabling not supported\n");
 364                 return -EINVAL;
 365         }
 366         if (dev->protocol->disable(dev) < 0) {
 367                 dev_err(&dev->dev, "disable failed\n");
 368                 return -EIO;
 369         }
 370
 371         dev_info(&dev->dev, "disabled\n");
 372         return 0;
 373 }
 374
 375 /**
 376  * pnp_activate_dev - activates a PnP device for use
 377  * @dev: pointer to the desired device
 378  *
 379  * does not validate or set resources so be careful.
 380  */
 381 int pnp_activate_dev(struct pnp_dev *dev)
 382 {
 383         int error;
 384
 385         if (dev->active)
 386                 return 0;
 387
 388         /* ensure resources are allocated */
 389         if (pnp_auto_config_dev(dev))
 390                 return -EBUSY;
 391
 392         error = pnp_start_dev(dev);
 393         if (error)
 394                 return error;
 395
 396         dev->active = 1;
 397         return 0;
 398 }
 399
 400 /**
 401  * pnp_disable_dev - disables device
 402  * @dev: pointer to the desired device
 403  *
 404  * inform the correct pnp protocol so that resources can be used by other devices
 405  */
 406 int pnp_disable_dev(struct pnp_dev *dev)
 407 {
 408         int error;
 409
 410         if (!dev->active)
 411                 return 0;
 412
 413         error = pnp_stop_dev(dev);
 414         if (error)
 415                 return error;
 416
 417         dev->active = 0;
 418
 419         /* release the resources so that other devices can use them */
 420         mutex_lock(&pnp_res_mutex);
 421         pnp_clean_resource_table(dev);
 422         mutex_unlock(&pnp_res_mutex);
 423
 424         return 0;
 425 }
 426
 427 EXPORT_SYMBOL(pnp_start_dev);
 428 EXPORT_SYMBOL(pnp_stop_dev);
 429 EXPORT_SYMBOL(pnp_activate_dev);
 430 EXPORT_SYMBOL(pnp_disable_dev);