kernel/irq/dummychip.c

   1 /*
   2  * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
   3  * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
   4  *
   5  * This file contains the dummy interrupt chip implementation
   6  */
   7 #include <linux/interrupt.h>
   8 #include <linux/irq.h>
   9 #include <linux/export.h>
  10
  11 #include "internals.h"
  12
  13 /*
  14  * What should we do if we get a hw irq event on an illegal vector?
  15  * Each architecture has to answer this themself.
  16  */
  17 static void ack_bad(struct irq_data *data)
  18 {
  19         struct irq_desc *desc = irq_data_to_desc(data);
  20
  21         print_irq_desc(data->irq, desc);
  22         ack_bad_irq(data->irq);
  23 }
  24
  25 /*
  26  * NOP functions
  27  */
  28 static void noop(struct irq_data *data) { }
  29
  30 static unsigned int noop_ret(struct irq_data *data)
  31 {
  32         return 0;
  33 }
  34
  35 /*
  36  * Generic no controller implementation
  37  */
  38 struct irq_chip no_irq_chip = {
  39         .name           = "none",
  40         .irq_startup    = noop_ret,
  41         .irq_shutdown   = noop,
  42         .irq_enable     = noop,
  43         .irq_disable    = noop,
  44         .irq_ack        = ack_bad,
  45 };
  46
  47 /*
  48  * Generic dummy implementation which can be used for
  49  * real dumb interrupt sources
  50  */
  51 struct irq_chip dummy_irq_chip = {
  52         .name           = "dummy",
  53         .irq_startup    = noop_ret,
  54         .irq_shutdown   = noop,
  55         .irq_enable     = noop,
  56         .irq_disable    = noop,
  57         .irq_ack        = noop,
  58         .irq_mask       = noop,
  59         .irq_unmask     = noop,
  60         .flags          = IRQCHIP_SKIP_SET_WAKE,
  61 };
  62 EXPORT_SYMBOL_GPL(dummy_irq_chip);