release/src-rt-6.x.4708/linux/linux-2.6.36/arch/arm/mach-s3c2440/irq.c

   1 /* linux/arch/arm/mach-s3c2440/irq.c
   2  *
   3  * Copyright (c) 2003-2004 Simtec Electronics
   4  *      Ben Dooks <ben@simtec.co.uk>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20 */
  21
  22 #include <linux/init.h>
  23 #include <linux/module.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/ioport.h>
  26 #include <linux/sysdev.h>
  27 #include <linux/io.h>
  28
  29 #include <mach/hardware.h>
  30 #include <asm/irq.h>
  31
  32 #include <asm/mach/irq.h>
  33
  34 #include <mach/regs-irq.h>
  35 #include <mach/regs-gpio.h>
  36
  37 #include <plat/cpu.h>
  38 #include <plat/pm.h>
  39 #include <plat/irq.h>
  40
  41 /* WDT/AC97 */
  42
  43 static void s3c_irq_demux_wdtac97(unsigned int irq,
  44                                   struct irq_desc *desc)
  45 {
  46         unsigned int subsrc, submsk;
  47
  48         /* read the current pending interrupts, and the mask
  49          * for what it is available */
  50
  51         subsrc = __raw_readl(S3C2410_SUBSRCPND);
  52         submsk = __raw_readl(S3C2410_INTSUBMSK);
  53
  54         subsrc &= ~submsk;
  55         subsrc >>= 13;
  56         subsrc &= 3;
  57
  58         if (subsrc != 0) {
  59                 if (subsrc & 1) {
  60                         generic_handle_irq(IRQ_S3C2440_WDT);
  61                 }
  62                 if (subsrc & 2) {
  63                         generic_handle_irq(IRQ_S3C2440_AC97);
  64                 }
  65         }
  66 }
  67
  68
  69 #define INTMSK_WDT       (1UL << (IRQ_WDT - IRQ_EINT0))
  70
  71 static void
  72 s3c_irq_wdtac97_mask(unsigned int irqno)
  73 {
  74         s3c_irqsub_mask(irqno, INTMSK_WDT, 3<<13);
  75 }
  76
  77 static void
  78 s3c_irq_wdtac97_unmask(unsigned int irqno)
  79 {
  80         s3c_irqsub_unmask(irqno, INTMSK_WDT);
  81 }
  82
  83 static void
  84 s3c_irq_wdtac97_ack(unsigned int irqno)
  85 {
  86         s3c_irqsub_maskack(irqno, INTMSK_WDT, 3<<13);
  87 }
  88
  89 static struct irq_chip s3c_irq_wdtac97 = {
  90         .mask       = s3c_irq_wdtac97_mask,
  91         .unmask     = s3c_irq_wdtac97_unmask,
  92         .ack        = s3c_irq_wdtac97_ack,
  93 };
  94
  95 static int s3c2440_irq_add(struct sys_device *sysdev)
  96 {
  97         unsigned int irqno;
  98
  99         printk("S3C2440: IRQ Support\n");
 100
 101         /* add new chained handler for wdt, ac7 */
 102
 103         set_irq_chip(IRQ_WDT, &s3c_irq_level_chip);
 104         set_irq_handler(IRQ_WDT, handle_level_irq);
 105         set_irq_chained_handler(IRQ_WDT, s3c_irq_demux_wdtac97);
 106
 107         for (irqno = IRQ_S3C2440_WDT; irqno <= IRQ_S3C2440_AC97; irqno++) {
 108                 set_irq_chip(irqno, &s3c_irq_wdtac97);
 109                 set_irq_handler(irqno, handle_level_irq);
 110                 set_irq_flags(irqno, IRQF_VALID);
 111         }
 112
 113         return 0;
 114 }
 115
 116 static struct sysdev_driver s3c2440_irq_driver = {
 117         .add            = s3c2440_irq_add,
 118 };
 119
 120 static int s3c2440_irq_init(void)
 121 {
 122         return sysdev_driver_register(&s3c2440_sysclass, &s3c2440_irq_driver);
 123 }
 124
 125 arch_initcall(s3c2440_irq_init);