arch/arm/mach-vt8500/irq.c

   1 /*
   2  *  arch/arm/mach-vt8500/irq.c
   3  *
   4  *  Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
   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 #include <linux/io.h>
  22 #include <linux/irq.h>
  23 #include <linux/interrupt.h>
  24
  25 #include <asm/irq.h>
  26
  27 #include "devices.h"
  28
  29 #define VT8500_IC_DCTR          0x40            /* Destination control
  30                                                 register, 64*u8 */
  31 #define VT8500_INT_ENABLE       (1 << 3)
  32 #define VT8500_TRIGGER_HIGH     (0 << 4)
  33 #define VT8500_TRIGGER_RISING   (1 << 4)
  34 #define VT8500_TRIGGER_FALLING  (2 << 4)
  35 #define VT8500_EDGE             ( VT8500_TRIGGER_RISING \
  36                                 | VT8500_TRIGGER_FALLING)
  37 #define VT8500_IC_STATUS        0x80            /* Interrupt status, 2*u32 */
  38
  39 static void __iomem *ic_regbase;
  40 static void __iomem *sic_regbase;
  41
  42 static void vt8500_irq_mask(struct irq_data *d)
  43 {
  44         void __iomem *base = ic_regbase;
  45         unsigned irq = d->irq;
  46         u8 edge;
  47
  48         if (irq >= 64) {
  49                 base = sic_regbase;
  50                 irq -= 64;
  51         }
  52         edge = readb(base + VT8500_IC_DCTR + irq) & VT8500_EDGE;
  53         if (edge) {
  54                 void __iomem *stat_reg = base + VT8500_IC_STATUS
  55                                                 + (irq < 32 ? 0 : 4);
  56                 unsigned status = readl(stat_reg);
  57
  58                 status |= (1 << (irq & 0x1f));
  59                 writel(status, stat_reg);
  60         } else {
  61                 u8 dctr = readb(base + VT8500_IC_DCTR + irq);
  62
  63                 dctr &= ~VT8500_INT_ENABLE;
  64                 writeb(dctr, base + VT8500_IC_DCTR + irq);
  65         }
  66 }
  67
  68 static void vt8500_irq_unmask(struct irq_data *d)
  69 {
  70         void __iomem *base = ic_regbase;
  71         unsigned irq = d->irq;
  72         u8 dctr;
  73
  74         if (irq >= 64) {
  75                 base = sic_regbase;
  76                 irq -= 64;
  77         }
  78         dctr = readb(base + VT8500_IC_DCTR + irq);
  79         dctr |= VT8500_INT_ENABLE;
  80         writeb(dctr, base + VT8500_IC_DCTR + irq);
  81 }
  82
  83 static int vt8500_irq_set_type(struct irq_data *d, unsigned int flow_type)
  84 {
  85         void __iomem *base = ic_regbase;
  86         unsigned irq = d->irq;
  87         unsigned orig_irq = irq;
  88         u8 dctr;
  89
  90         if (irq >= 64) {
  91                 base = sic_regbase;
  92                 irq -= 64;
  93         }
  94
  95         dctr = readb(base + VT8500_IC_DCTR + irq);
  96         dctr &= ~VT8500_EDGE;
  97
  98         switch (flow_type) {
  99         case IRQF_TRIGGER_LOW:
 100                 return -EINVAL;
 101         case IRQF_TRIGGER_HIGH:
 102                 dctr |= VT8500_TRIGGER_HIGH;
 103                 __irq_set_handler_locked(orig_irq, handle_level_irq);
 104                 break;
 105         case IRQF_TRIGGER_FALLING:
 106                 dctr |= VT8500_TRIGGER_FALLING;
 107                 __irq_set_handler_locked(orig_irq, handle_edge_irq);
 108                 break;
 109         case IRQF_TRIGGER_RISING:
 110                 dctr |= VT8500_TRIGGER_RISING;
 111                 __irq_set_handler_locked(orig_irq, handle_edge_irq);
 112                 break;
 113         }
 114         writeb(dctr, base + VT8500_IC_DCTR + irq);
 115
 116         return 0;
 117 }
 118
 119 static struct irq_chip vt8500_irq_chip = {
 120         .name = "vt8500",
 121         .irq_ack = vt8500_irq_mask,
 122         .irq_mask = vt8500_irq_mask,
 123         .irq_unmask = vt8500_irq_unmask,
 124         .irq_set_type = vt8500_irq_set_type,
 125 };
 126
 127 void __init vt8500_init_irq(void)
 128 {
 129         unsigned int i;
 130
 131         ic_regbase = ioremap(wmt_ic_base, SZ_64K);
 132
 133         if (ic_regbase) {
 134                 /* Enable rotating priority for IRQ */
 135                 writel((1 << 6), ic_regbase + 0x20);
 136                 writel(0, ic_regbase + 0x24);
 137
 138                 for (i = 0; i < wmt_nr_irqs; i++) {
 139                         /* Disable all interrupts and route them to IRQ */
 140                         writeb(0x00, ic_regbase + VT8500_IC_DCTR + i);
 141
 142                         irq_set_chip_and_handler(i, &vt8500_irq_chip,
 143                                                  handle_level_irq);
 144                         set_irq_flags(i, IRQF_VALID);
 145                 }
 146         } else {
 147                 printk(KERN_ERR "Unable to remap the Interrupt Controller registers, not enabling IRQs!\n");
 148         }
 149 }
 150
 151 void __init wm8505_init_irq(void)
 152 {
 153         unsigned int i;
 154
 155         ic_regbase = ioremap(wmt_ic_base, SZ_64K);
 156         sic_regbase = ioremap(wmt_sic_base, SZ_64K);
 157
 158         if (ic_regbase && sic_regbase) {
 159                 /* Enable rotating priority for IRQ */
 160                 writel((1 << 6), ic_regbase + 0x20);
 161                 writel(0, ic_regbase + 0x24);
 162                 writel((1 << 6), sic_regbase + 0x20);
 163                 writel(0, sic_regbase + 0x24);
 164
 165                 for (i = 0; i < wmt_nr_irqs; i++) {
 166                         /* Disable all interrupts and route them to IRQ */
 167                         if (i < 64)
 168                                 writeb(0x00, ic_regbase + VT8500_IC_DCTR + i);
 169                         else
 170                                 writeb(0x00, sic_regbase + VT8500_IC_DCTR
 171                                                                 + i - 64);
 172
 173                         irq_set_chip_and_handler(i, &vt8500_irq_chip,
 174                                                  handle_level_irq);
 175                         set_irq_flags(i, IRQF_VALID);
 176                 }
 177         } else {
 178                 printk(KERN_ERR "Unable to remap the Interrupt Controller registers, not enabling IRQs!\n");
 179         }
 180 }