kernel/irq/chip.c

   1 /*
   2  * linux/kernel/irq/chip.c
   3  *
   4  * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
   5  * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
   6  *
   7  * This file contains the core interrupt handling code, for irq-chip
   8  * based architectures.
   9  *
  10  * Detailed information is available in Documentation/DocBook/genericirq
  11  */
  12
  13 #include <linux/irq.h>
  14 #include <linux/msi.h>
  15 #include <linux/module.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/kernel_stat.h>
  18
  19 #include "internals.h"
  20
  21 static void dynamic_irq_init_x(unsigned int irq, bool keep_chip_data)
  22 {
  23         struct irq_desc *desc;
  24         unsigned long flags;
  25
  26         desc = irq_to_desc(irq);
  27         if (!desc) {
  28                 WARN(1, KERN_ERR "Trying to initialize invalid IRQ%d\n", irq);
  29                 return;
  30         }
  31
  32         /* Ensure we don't have left over values from a previous use of this irq */
  33         raw_spin_lock_irqsave(&desc->lock, flags);
  34         desc->status = IRQ_DISABLED;
  35         desc->irq_data.chip = &no_irq_chip;
  36         desc->handle_irq = handle_bad_irq;
  37         desc->depth = 1;
  38         desc->irq_data.msi_desc = NULL;
  39         desc->irq_data.handler_data = NULL;
  40         if (!keep_chip_data)
  41                 desc->irq_data.chip_data = NULL;
  42         desc->action = NULL;
  43         desc->irq_count = 0;
  44         desc->irqs_unhandled = 0;
  45 #ifdef CONFIG_SMP
  46         cpumask_setall(desc->irq_data.affinity);
  47 #ifdef CONFIG_GENERIC_PENDING_IRQ
  48         cpumask_clear(desc->pending_mask);
  49 #endif
  50 #endif
  51         raw_spin_unlock_irqrestore(&desc->lock, flags);
  52 }
  53
  54 /**
  55  *      dynamic_irq_init - initialize a dynamically allocated irq
  56  *      @irq:   irq number to initialize
  57  */
  58 void dynamic_irq_init(unsigned int irq)
  59 {
  60         dynamic_irq_init_x(irq, false);
  61 }
  62
  63 /**
  64  *      dynamic_irq_init_keep_chip_data - initialize a dynamically allocated irq
  65  *      @irq:   irq number to initialize
  66  *
  67  *      does not set irq_to_desc(irq)->irq_data.chip_data to NULL
  68  */
  69 void dynamic_irq_init_keep_chip_data(unsigned int irq)
  70 {
  71         dynamic_irq_init_x(irq, true);
  72 }
  73
  74 static void dynamic_irq_cleanup_x(unsigned int irq, bool keep_chip_data)
  75 {
  76         struct irq_desc *desc = irq_to_desc(irq);
  77         unsigned long flags;
  78
  79         if (!desc) {
  80                 WARN(1, KERN_ERR "Trying to cleanup invalid IRQ%d\n", irq);
  81                 return;
  82         }
  83
  84         raw_spin_lock_irqsave(&desc->lock, flags);
  85         if (desc->action) {
  86                 raw_spin_unlock_irqrestore(&desc->lock, flags);
  87                 WARN(1, KERN_ERR "Destroying IRQ%d without calling free_irq\n",
  88                         irq);
  89                 return;
  90         }
  91         desc->irq_data.msi_desc = NULL;
  92         desc->irq_data.handler_data = NULL;
  93         if (!keep_chip_data)
  94                 desc->irq_data.chip_data = NULL;
  95         desc->handle_irq = handle_bad_irq;
  96         desc->irq_data.chip = &no_irq_chip;
  97         desc->name = NULL;
  98         clear_kstat_irqs(desc);
  99         raw_spin_unlock_irqrestore(&desc->lock, flags);
 100 }
 101
 102 /**
 103  *      dynamic_irq_cleanup - cleanup a dynamically allocated irq
 104  *      @irq:   irq number to initialize
 105  */
 106 void dynamic_irq_cleanup(unsigned int irq)
 107 {
 108         dynamic_irq_cleanup_x(irq, false);
 109 }
 110
 111 /**
 112  *      dynamic_irq_cleanup_keep_chip_data - cleanup a dynamically allocated irq
 113  *      @irq:   irq number to initialize
 114  *
 115  *      does not set irq_to_desc(irq)->irq_data.chip_data to NULL
 116  */
 117 void dynamic_irq_cleanup_keep_chip_data(unsigned int irq)
 118 {
 119         dynamic_irq_cleanup_x(irq, true);
 120 }
 121
 122
 123 /**
 124  *      set_irq_chip - set the irq chip for an irq
 125  *      @irq:   irq number
 126  *      @chip:  pointer to irq chip description structure
 127  */
 128 int set_irq_chip(unsigned int irq, struct irq_chip *chip)
 129 {
 130         struct irq_desc *desc = irq_to_desc(irq);
 131         unsigned long flags;
 132
 133         if (!desc) {
 134                 WARN(1, KERN_ERR "Trying to install chip for IRQ%d\n", irq);
 135                 return -EINVAL;
 136         }
 137
 138         if (!chip)
 139                 chip = &no_irq_chip;
 140
 141         raw_spin_lock_irqsave(&desc->lock, flags);
 142         irq_chip_set_defaults(chip);
 143         desc->irq_data.chip = chip;
 144         raw_spin_unlock_irqrestore(&desc->lock, flags);
 145
 146         return 0;
 147 }
 148 EXPORT_SYMBOL(set_irq_chip);
 149
 150 /**
 151  *      set_irq_type - set the irq trigger type for an irq
 152  *      @irq:   irq number
 153  *      @type:  IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
 154  */
 155 int set_irq_type(unsigned int irq, unsigned int type)
 156 {
 157         struct irq_desc *desc = irq_to_desc(irq);
 158         unsigned long flags;
 159         int ret = -ENXIO;
 160
 161         if (!desc) {
 162                 printk(KERN_ERR "Trying to set irq type for IRQ%d\n", irq);
 163                 return -ENODEV;
 164         }
 165
 166         type &= IRQ_TYPE_SENSE_MASK;
 167         if (type == IRQ_TYPE_NONE)
 168                 return 0;
 169
 170         raw_spin_lock_irqsave(&desc->lock, flags);
 171         ret = __irq_set_trigger(desc, irq, type);
 172         raw_spin_unlock_irqrestore(&desc->lock, flags);
 173         return ret;
 174 }
 175 EXPORT_SYMBOL(set_irq_type);
 176
 177 /**
 178  *      set_irq_data - set irq type data for an irq
 179  *      @irq:   Interrupt number
 180  *      @data:  Pointer to interrupt specific data
 181  *
 182  *      Set the hardware irq controller data for an irq
 183  */
 184 int set_irq_data(unsigned int irq, void *data)
 185 {
 186         struct irq_desc *desc = irq_to_desc(irq);
 187         unsigned long flags;
 188
 189         if (!desc) {
 190                 printk(KERN_ERR
 191                        "Trying to install controller data for IRQ%d\n", irq);
 192                 return -EINVAL;
 193         }
 194
 195         raw_spin_lock_irqsave(&desc->lock, flags);
 196         desc->irq_data.handler_data = data;
 197         raw_spin_unlock_irqrestore(&desc->lock, flags);
 198         return 0;
 199 }
 200 EXPORT_SYMBOL(set_irq_data);
 201
 202 /**
 203  *      set_irq_msi - set MSI descriptor data for an irq
 204  *      @irq:   Interrupt number
 205  *      @entry: Pointer to MSI descriptor data
 206  *
 207  *      Set the MSI descriptor entry for an irq
 208  */
 209 int set_irq_msi(unsigned int irq, struct msi_desc *entry)
 210 {
 211         struct irq_desc *desc = irq_to_desc(irq);
 212         unsigned long flags;
 213
 214         if (!desc) {
 215                 printk(KERN_ERR
 216                        "Trying to install msi data for IRQ%d\n", irq);
 217                 return -EINVAL;
 218         }
 219
 220         raw_spin_lock_irqsave(&desc->lock, flags);
 221         desc->irq_data.msi_desc = entry;
 222         if (entry)
 223                 entry->irq = irq;
 224         raw_spin_unlock_irqrestore(&desc->lock, flags);
 225         return 0;
 226 }
 227
 228 /**
 229  *      set_irq_chip_data - set irq chip data for an irq
 230  *      @irq:   Interrupt number
 231  *      @data:  Pointer to chip specific data
 232  *
 233  *      Set the hardware irq chip data for an irq
 234  */
 235 int set_irq_chip_data(unsigned int irq, void *data)
 236 {
 237         struct irq_desc *desc = irq_to_desc(irq);
 238         unsigned long flags;
 239
 240         if (!desc) {
 241                 printk(KERN_ERR
 242                        "Trying to install chip data for IRQ%d\n", irq);
 243                 return -EINVAL;
 244         }
 245
 246         if (!desc->irq_data.chip) {
 247                 printk(KERN_ERR "BUG: bad set_irq_chip_data(IRQ#%d)\n", irq);
 248                 return -EINVAL;
 249         }
 250
 251         raw_spin_lock_irqsave(&desc->lock, flags);
 252         desc->irq_data.chip_data = data;
 253         raw_spin_unlock_irqrestore(&desc->lock, flags);
 254
 255         return 0;
 256 }
 257 EXPORT_SYMBOL(set_irq_chip_data);
 258
 259 /**
 260  *      set_irq_nested_thread - Set/Reset the IRQ_NESTED_THREAD flag of an irq
 261  *
 262  *      @irq:   Interrupt number
 263  *      @nest:  0 to clear / 1 to set the IRQ_NESTED_THREAD flag
 264  *
 265  *      The IRQ_NESTED_THREAD flag indicates that on
 266  *      request_threaded_irq() no separate interrupt thread should be
 267  *      created for the irq as the handler are called nested in the
 268  *      context of a demultiplexing interrupt handler thread.
 269  */
 270 void set_irq_nested_thread(unsigned int irq, int nest)
 271 {
 272         struct irq_desc *desc = irq_to_desc(irq);
 273         unsigned long flags;
 274
 275         if (!desc)
 276                 return;
 277
 278         raw_spin_lock_irqsave(&desc->lock, flags);
 279         if (nest)
 280                 desc->status |= IRQ_NESTED_THREAD;
 281         else
 282                 desc->status &= ~IRQ_NESTED_THREAD;
 283         raw_spin_unlock_irqrestore(&desc->lock, flags);
 284 }
 285 EXPORT_SYMBOL_GPL(set_irq_nested_thread);
 286
 287 /*
 288  * default enable function
 289  */
 290 static void default_enable(struct irq_data *data)
 291 {
 292         struct irq_desc *desc = irq_data_to_desc(data);
 293
 294         desc->irq_data.chip->irq_unmask(&desc->irq_data);
 295         desc->status &= ~IRQ_MASKED;
 296 }
 297
 298 /*
 299  * default disable function
 300  */
 301 static void default_disable(struct irq_data *data)
 302 {
 303 }
 304
 305 /*
 306  * default startup function
 307  */
 308 static unsigned int default_startup(unsigned int irq)
 309 {
 310         struct irq_desc *desc = irq_to_desc(irq);
 311
 312         desc->irq_data.chip->irq_enable(&desc->irq_data);
 313         return 0;
 314 }
 315
 316 /*
 317  * default shutdown function
 318  */
 319 static void default_shutdown(struct irq_data *data)
 320 {
 321         struct irq_desc *desc = irq_data_to_desc(data);
 322
 323         desc->irq_data.chip->irq_mask(&desc->irq_data);
 324         desc->status |= IRQ_MASKED;
 325 }
 326
 327 /* Temporary migration helpers */
 328 static void compat_irq_mask(struct irq_data *data)
 329 {
 330         data->chip->mask(data->irq);
 331 }
 332
 333 static void compat_irq_unmask(struct irq_data *data)
 334 {
 335         data->chip->unmask(data->irq);
 336 }
 337
 338 static void compat_irq_ack(struct irq_data *data)
 339 {
 340         data->chip->ack(data->irq);
 341 }
 342
 343 static void compat_irq_mask_ack(struct irq_data *data)
 344 {
 345         data->chip->mask_ack(data->irq);
 346 }
 347
 348 static void compat_irq_eoi(struct irq_data *data)
 349 {
 350         data->chip->eoi(data->irq);
 351 }
 352
 353 static void compat_irq_enable(struct irq_data *data)
 354 {
 355         data->chip->enable(data->irq);
 356 }
 357
 358 static void compat_irq_disable(struct irq_data *data)
 359 {
 360         data->chip->disable(data->irq);
 361 }
 362
 363 static void compat_irq_shutdown(struct irq_data *data)
 364 {
 365         data->chip->shutdown(data->irq);
 366 }
 367
 368 static void compat_bus_lock(struct irq_data *data)
 369 {
 370         data->chip->bus_lock(data->irq);
 371 }
 372
 373 static void compat_bus_sync_unlock(struct irq_data *data)
 374 {
 375         data->chip->bus_sync_unlock(data->irq);
 376 }
 377
 378 /*
 379  * Fixup enable/disable function pointers
 380  */
 381 void irq_chip_set_defaults(struct irq_chip *chip)
 382 {
 383         /*
 384          * Compat fixup functions need to be before we set the
 385          * defaults for enable/disable/startup/shutdown
 386          */
 387         if (chip->enable)
 388                 chip->irq_enable = compat_irq_enable;
 389         if (chip->disable)
 390                 chip->irq_disable = compat_irq_disable;
 391         if (chip->shutdown)
 392                 chip->irq_shutdown = compat_irq_shutdown;
 393
 394         /*
 395          * The real defaults
 396          */
 397         if (!chip->irq_enable)
 398                 chip->irq_enable = default_enable;
 399         if (!chip->irq_disable)
 400                 chip->irq_disable = default_disable;
 401         if (!chip->startup)
 402                 chip->startup = default_startup;
 403         /*
 404          * We use chip->irq_disable, when the user provided its own. When
 405          * we have default_disable set for chip->irq_disable, then we need
 406          * to use default_shutdown, otherwise the irq line is not
 407          * disabled on free_irq():
 408          */
 409         if (!chip->irq_shutdown)
 410                 chip->irq_shutdown = chip->irq_disable != default_disable ?
 411                         chip->irq_disable : default_shutdown;
 412         if (!chip->end)
 413                 chip->end = dummy_irq_chip.end;
 414
 415         /*
 416          * Now fix up the remaining compat handlers
 417          */
 418         if (chip->bus_lock)
 419                 chip->irq_bus_lock = compat_bus_lock;
 420         if (chip->bus_sync_unlock)
 421                 chip->irq_bus_sync_unlock = compat_bus_sync_unlock;
 422         if (chip->mask)
 423                 chip->irq_mask = compat_irq_mask;
 424         if (chip->unmask)
 425                 chip->irq_unmask = compat_irq_unmask;
 426         if (chip->ack)
 427                 chip->irq_ack = compat_irq_ack;
 428         if (chip->mask_ack)
 429                 chip->irq_mask_ack = compat_irq_mask_ack;
 430         if (chip->eoi)
 431                 chip->irq_eoi = compat_irq_eoi;
 432 }
 433
 434 static inline void mask_ack_irq(struct irq_desc *desc)
 435 {
 436         if (desc->irq_data.chip->irq_mask_ack)
 437                 desc->irq_data.chip->irq_mask_ack(&desc->irq_data);
 438         else {
 439                 desc->irq_data.chip->irq_mask(&desc->irq_data);
 440                 if (desc->irq_data.chip->irq_ack)
 441                         desc->irq_data.chip->irq_ack(&desc->irq_data);
 442         }
 443         desc->status |= IRQ_MASKED;
 444 }
 445
 446 static inline void mask_irq(struct irq_desc *desc)
 447 {
 448         if (desc->irq_data.chip->irq_mask) {
 449                 desc->irq_data.chip->irq_mask(&desc->irq_data);
 450                 desc->status |= IRQ_MASKED;
 451         }
 452 }
 453
 454 static inline void unmask_irq(struct irq_desc *desc)
 455 {
 456         if (desc->irq_data.chip->irq_unmask) {
 457                 desc->irq_data.chip->irq_unmask(&desc->irq_data);
 458                 desc->status &= ~IRQ_MASKED;
 459         }
 460 }
 461
 462 /*
 463  *      handle_nested_irq - Handle a nested irq from a irq thread
 464  *      @irq:   the interrupt number
 465  *
 466  *      Handle interrupts which are nested into a threaded interrupt
 467  *      handler. The handler function is called inside the calling
 468  *      threads context.
 469  */
 470 void handle_nested_irq(unsigned int irq)
 471 {
 472         struct irq_desc *desc = irq_to_desc(irq);
 473         struct irqaction *action;
 474         irqreturn_t action_ret;
 475
 476         might_sleep();
 477
 478         raw_spin_lock_irq(&desc->lock);
 479
 480         kstat_incr_irqs_this_cpu(irq, desc);
 481
 482         action = desc->action;
 483         if (unlikely(!action || (desc->status & IRQ_DISABLED)))
 484                 goto out_unlock;
 485
 486         desc->status |= IRQ_INPROGRESS;
 487         raw_spin_unlock_irq(&desc->lock);
 488
 489         action_ret = action->thread_fn(action->irq, action->dev_id);
 490         if (!noirqdebug)
 491                 note_interrupt(irq, desc, action_ret);
 492
 493         raw_spin_lock_irq(&desc->lock);
 494         desc->status &= ~IRQ_INPROGRESS;
 495
 496 out_unlock:
 497         raw_spin_unlock_irq(&desc->lock);
 498 }
 499 EXPORT_SYMBOL_GPL(handle_nested_irq);
 500
 501 /**
 502  *      handle_simple_irq - Simple and software-decoded IRQs.
 503  *      @irq:   the interrupt number
 504  *      @desc:  the interrupt description structure for this irq
 505  *
 506  *      Simple interrupts are either sent from a demultiplexing interrupt
 507  *      handler or come from hardware, where no interrupt hardware control
 508  *      is necessary.
 509  *
 510  *      Note: The caller is expected to handle the ack, clear, mask and
 511  *      unmask issues if necessary.
 512  */
 513 void
 514 handle_simple_irq(unsigned int irq, struct irq_desc *desc)
 515 {
 516         struct irqaction *action;
 517         irqreturn_t action_ret;
 518
 519         raw_spin_lock(&desc->lock);
 520
 521         if (unlikely(desc->status & IRQ_INPROGRESS))
 522                 goto out_unlock;
 523         desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
 524         kstat_incr_irqs_this_cpu(irq, desc);
 525
 526         action = desc->action;
 527         if (unlikely(!action || (desc->status & IRQ_DISABLED)))
 528                 goto out_unlock;
 529
 530         desc->status |= IRQ_INPROGRESS;
 531         raw_spin_unlock(&desc->lock);
 532
 533         action_ret = handle_IRQ_event(irq, action);
 534         if (!noirqdebug)
 535                 note_interrupt(irq, desc, action_ret);
 536
 537         raw_spin_lock(&desc->lock);
 538         desc->status &= ~IRQ_INPROGRESS;
 539 out_unlock:
 540         raw_spin_unlock(&desc->lock);
 541 }
 542
 543 /**
 544  *      handle_level_irq - Level type irq handler
 545  *      @irq:   the interrupt number
 546  *      @desc:  the interrupt description structure for this irq
 547  *
 548  *      Level type interrupts are active as long as the hardware line has
 549  *      the active level. This may require to mask the interrupt and unmask
 550  *      it after the associated handler has acknowledged the device, so the
 551  *      interrupt line is back to inactive.
 552  */
 553 void
 554 handle_level_irq(unsigned int irq, struct irq_desc *desc)
 555 {
 556         struct irqaction *action;
 557         irqreturn_t action_ret;
 558
 559         raw_spin_lock(&desc->lock);
 560         mask_ack_irq(desc);
 561
 562         if (unlikely(desc->status & IRQ_INPROGRESS))
 563                 goto out_unlock;
 564         desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
 565         kstat_incr_irqs_this_cpu(irq, desc);
 566
 567         /*
 568          * If its disabled or no action available
 569          * keep it masked and get out of here
 570          */
 571         action = desc->action;
 572         if (unlikely(!action || (desc->status & IRQ_DISABLED)))
 573                 goto out_unlock;
 574
 575         desc->status |= IRQ_INPROGRESS;
 576         raw_spin_unlock(&desc->lock);
 577
 578         action_ret = handle_IRQ_event(irq, action);
 579         if (!noirqdebug)
 580                 note_interrupt(irq, desc, action_ret);
 581
 582         raw_spin_lock(&desc->lock);
 583         desc->status &= ~IRQ_INPROGRESS;
 584
 585         if (!(desc->status & (IRQ_DISABLED | IRQ_ONESHOT)))
 586                 unmask_irq(desc);
 587 out_unlock:
 588         raw_spin_unlock(&desc->lock);
 589 }
 590 EXPORT_SYMBOL_GPL(handle_level_irq);
 591
 592 /**
 593  *      handle_fasteoi_irq - irq handler for transparent controllers
 594  *      @irq:   the interrupt number
 595  *      @desc:  the interrupt description structure for this irq
 596  *
 597  *      Only a single callback will be issued to the chip: an ->eoi()
 598  *      call when the interrupt has been serviced. This enables support
 599  *      for modern forms of interrupt handlers, which handle the flow
 600  *      details in hardware, transparently.
 601  */
 602 void
 603 handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
 604 {
 605         struct irqaction *action;
 606         irqreturn_t action_ret;
 607
 608         raw_spin_lock(&desc->lock);
 609
 610         if (unlikely(desc->status & IRQ_INPROGRESS))
 611                 goto out;
 612
 613         desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
 614         kstat_incr_irqs_this_cpu(irq, desc);
 615
 616         /*
 617          * If its disabled or no action available
 618          * then mask it and get out of here:
 619          */
 620         action = desc->action;
 621         if (unlikely(!action || (desc->status & IRQ_DISABLED))) {
 622                 desc->status |= IRQ_PENDING;
 623                 mask_irq(desc);
 624                 goto out;
 625         }
 626
 627         desc->status |= IRQ_INPROGRESS;
 628         desc->status &= ~IRQ_PENDING;
 629         raw_spin_unlock(&desc->lock);
 630
 631         action_ret = handle_IRQ_event(irq, action);
 632         if (!noirqdebug)
 633                 note_interrupt(irq, desc, action_ret);
 634
 635         raw_spin_lock(&desc->lock);
 636         desc->status &= ~IRQ_INPROGRESS;
 637 out:
 638         desc->irq_data.chip->irq_eoi(&desc->irq_data);
 639
 640         raw_spin_unlock(&desc->lock);
 641 }
 642
 643 /**
 644  *      handle_edge_irq - edge type IRQ handler
 645  *      @irq:   the interrupt number
 646  *      @desc:  the interrupt description structure for this irq
 647  *
 648  *      Interrupt occures on the falling and/or rising edge of a hardware
 649  *      signal. The occurence is latched into the irq controller hardware
 650  *      and must be acked in order to be reenabled. After the ack another
 651  *      interrupt can happen on the same source even before the first one
 652  *      is handled by the associated event handler. If this happens it
 653  *      might be necessary to disable (mask) the interrupt depending on the
 654  *      controller hardware. This requires to reenable the interrupt inside
 655  *      of the loop which handles the interrupts which have arrived while
 656  *      the handler was running. If all pending interrupts are handled, the
 657  *      loop is left.
 658  */
 659 void
 660 handle_edge_irq(unsigned int irq, struct irq_desc *desc)
 661 {
 662         raw_spin_lock(&desc->lock);
 663
 664         desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
 665
 666         /*
 667          * If we're currently running this IRQ, or its disabled,
 668          * we shouldn't process the IRQ. Mark it pending, handle
 669          * the necessary masking and go out
 670          */
 671         if (unlikely((desc->status & (IRQ_INPROGRESS | IRQ_DISABLED)) ||
 672                     !desc->action)) {
 673                 desc->status |= (IRQ_PENDING | IRQ_MASKED);
 674                 mask_ack_irq(desc);
 675                 goto out_unlock;
 676         }
 677         kstat_incr_irqs_this_cpu(irq, desc);
 678
 679         /* Start handling the irq */
 680         desc->irq_data.chip->irq_ack(&desc->irq_data);
 681
 682         /* Mark the IRQ currently in progress.*/
 683         desc->status |= IRQ_INPROGRESS;
 684
 685         do {
 686                 struct irqaction *action = desc->action;
 687                 irqreturn_t action_ret;
 688
 689                 if (unlikely(!action)) {
 690                         mask_irq(desc);
 691                         goto out_unlock;
 692                 }
 693
 694                 /*
 695                  * When another irq arrived while we were handling
 696                  * one, we could have masked the irq.
 697                  * Renable it, if it was not disabled in meantime.
 698                  */
 699                 if (unlikely((desc->status &
 700                                (IRQ_PENDING | IRQ_MASKED | IRQ_DISABLED)) ==
 701                               (IRQ_PENDING | IRQ_MASKED))) {
 702                         unmask_irq(desc);
 703                 }
 704
 705                 desc->status &= ~IRQ_PENDING;
 706                 raw_spin_unlock(&desc->lock);
 707                 action_ret = handle_IRQ_event(irq, action);
 708                 if (!noirqdebug)
 709                         note_interrupt(irq, desc, action_ret);
 710                 raw_spin_lock(&desc->lock);
 711
 712         } while ((desc->status & (IRQ_PENDING | IRQ_DISABLED)) == IRQ_PENDING);
 713
 714         desc->status &= ~IRQ_INPROGRESS;
 715 out_unlock:
 716         raw_spin_unlock(&desc->lock);
 717 }
 718
 719 /**
 720  *      handle_percpu_irq - Per CPU local irq handler
 721  *      @irq:   the interrupt number
 722  *      @desc:  the interrupt description structure for this irq
 723  *
 724  *      Per CPU interrupts on SMP machines without locking requirements
 725  */
 726 void
 727 handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
 728 {
 729         irqreturn_t action_ret;
 730
 731         kstat_incr_irqs_this_cpu(irq, desc);
 732
 733         if (desc->irq_data.chip->irq_ack)
 734                 desc->irq_data.chip->irq_ack(&desc->irq_data);
 735
 736         action_ret = handle_IRQ_event(irq, desc->action);
 737         if (!noirqdebug)
 738                 note_interrupt(irq, desc, action_ret);
 739
 740         if (desc->irq_data.chip->irq_eoi)
 741                 desc->irq_data.chip->irq_eoi(&desc->irq_data);
 742 }
 743
 744 void
 745 __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
 746                   const char *name)
 747 {
 748         struct irq_desc *desc = irq_to_desc(irq);
 749         unsigned long flags;
 750
 751         if (!desc) {
 752                 printk(KERN_ERR
 753                        "Trying to install type control for IRQ%d\n", irq);
 754                 return;
 755         }
 756
 757         if (!handle)
 758                 handle = handle_bad_irq;
 759         else if (desc->irq_data.chip == &no_irq_chip) {
 760                 printk(KERN_WARNING "Trying to install %sinterrupt handler "
 761                        "for IRQ%d\n", is_chained ? "chained " : "", irq);
 762                 /*
 763                  * Some ARM implementations install a handler for really dumb
 764                  * interrupt hardware without setting an irq_chip. This worked
 765                  * with the ARM no_irq_chip but the check in setup_irq would
 766                  * prevent us to setup the interrupt at all. Switch it to
 767                  * dummy_irq_chip for easy transition.
 768                  */
 769                 desc->irq_data.chip = &dummy_irq_chip;
 770         }
 771
 772         chip_bus_lock(desc);
 773         raw_spin_lock_irqsave(&desc->lock, flags);
 774
 775         /* Uninstall? */
 776         if (handle == handle_bad_irq) {
 777                 if (desc->irq_data.chip != &no_irq_chip)
 778                         mask_ack_irq(desc);
 779                 desc->status |= IRQ_DISABLED;
 780                 desc->depth = 1;
 781         }
 782         desc->handle_irq = handle;
 783         desc->name = name;
 784
 785         if (handle != handle_bad_irq && is_chained) {
 786                 desc->status &= ~IRQ_DISABLED;
 787                 desc->status |= IRQ_NOREQUEST | IRQ_NOPROBE;
 788                 desc->depth = 0;
 789                 desc->irq_data.chip->startup(irq);
 790         }
 791         raw_spin_unlock_irqrestore(&desc->lock, flags);
 792         chip_bus_sync_unlock(desc);
 793 }
 794 EXPORT_SYMBOL_GPL(__set_irq_handler);
 795
 796 void
 797 set_irq_chip_and_handler(unsigned int irq, struct irq_chip *chip,
 798                          irq_flow_handler_t handle)
 799 {
 800         set_irq_chip(irq, chip);
 801         __set_irq_handler(irq, handle, 0, NULL);
 802 }
 803
 804 void
 805 set_irq_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
 806                               irq_flow_handler_t handle, const char *name)
 807 {
 808         set_irq_chip(irq, chip);
 809         __set_irq_handler(irq, handle, 0, name);
 810 }
 811
 812 void set_irq_noprobe(unsigned int irq)
 813 {
 814         struct irq_desc *desc = irq_to_desc(irq);
 815         unsigned long flags;
 816
 817         if (!desc) {
 818                 printk(KERN_ERR "Trying to mark IRQ%d non-probeable\n", irq);
 819                 return;
 820         }
 821
 822         raw_spin_lock_irqsave(&desc->lock, flags);
 823         desc->status |= IRQ_NOPROBE;
 824         raw_spin_unlock_irqrestore(&desc->lock, flags);
 825 }
 826
 827 void set_irq_probe(unsigned int irq)
 828 {
 829         struct irq_desc *desc = irq_to_desc(irq);
 830         unsigned long flags;
 831
 832         if (!desc) {
 833                 printk(KERN_ERR "Trying to mark IRQ%d probeable\n", irq);
 834                 return;
 835         }
 836
 837         raw_spin_lock_irqsave(&desc->lock, flags);
 838         desc->status &= ~IRQ_NOPROBE;
 839         raw_spin_unlock_irqrestore(&desc->lock, flags);
 840 }