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