arch/arm/plat-s5p/irq-gpioint.c

   1 /* linux/arch/arm/plat-s5p/irq-gpioint.c
   2  *
   3  * Copyright (c) 2010 Samsung Electronics Co., Ltd.
   4  * Author: Kyungmin Park <kyungmin.park@samsung.com>
   5  * Author: Joonyoung Shim <jy0922.shim@samsung.com>
   6  * Author: Marek Szyprowski <m.szyprowski@samsung.com>
   7  *
   8  *  This program is free software; you can redistribute  it and/or modify it
   9  *  under  the terms of  the GNU General  Public License as published by the
  10  *  Free Software Foundation;  either version 2 of the  License, or (at your
  11  *  option) any later version.
  12  *
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/irq.h>
  18 #include <linux/io.h>
  19 #include <linux/gpio.h>
  20 #include <linux/slab.h>
  21
  22 #include <mach/map.h>
  23 #include <plat/gpio-core.h>
  24 #include <plat/gpio-cfg.h>
  25
  26 #include <asm/mach/irq.h>
  27
  28 #define GPIO_BASE(chip)         (((unsigned long)(chip)->base) & 0xFFFFF000u)
  29
  30 #define CON_OFFSET              0x700
  31 #define MASK_OFFSET             0x900
  32 #define PEND_OFFSET             0xA00
  33 #define REG_OFFSET(x)           ((x) << 2)
  34
  35 struct s5p_gpioint_bank {
  36         struct list_head        list;
  37         int                     start;
  38         int                     nr_groups;
  39         int                     irq;
  40         struct samsung_gpio_chip        **chips;
  41         void                    (*handler)(unsigned int, struct irq_desc *);
  42 };
  43
  44 LIST_HEAD(banks);
  45
  46 static int s5p_gpioint_set_type(struct irq_data *d, unsigned int type)
  47 {
  48         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
  49         struct irq_chip_type *ct = gc->chip_types;
  50         unsigned int shift = (d->irq - gc->irq_base) << 2;
  51
  52         switch (type) {
  53         case IRQ_TYPE_EDGE_RISING:
  54                 type = S5P_IRQ_TYPE_EDGE_RISING;
  55                 break;
  56         case IRQ_TYPE_EDGE_FALLING:
  57                 type = S5P_IRQ_TYPE_EDGE_FALLING;
  58                 break;
  59         case IRQ_TYPE_EDGE_BOTH:
  60                 type = S5P_IRQ_TYPE_EDGE_BOTH;
  61                 break;
  62         case IRQ_TYPE_LEVEL_HIGH:
  63                 type = S5P_IRQ_TYPE_LEVEL_HIGH;
  64                 break;
  65         case IRQ_TYPE_LEVEL_LOW:
  66                 type = S5P_IRQ_TYPE_LEVEL_LOW;
  67                 break;
  68         case IRQ_TYPE_NONE:
  69         default:
  70                 printk(KERN_WARNING "No irq type\n");
  71                 return -EINVAL;
  72         }
  73
  74         gc->type_cache &= ~(0x7 << shift);
  75         gc->type_cache |= type << shift;
  76         writel(gc->type_cache, gc->reg_base + ct->regs.type);
  77         return 0;
  78 }
  79
  80 static void s5p_gpioint_handler(unsigned int irq, struct irq_desc *desc)
  81 {
  82         struct s5p_gpioint_bank *bank = irq_get_handler_data(irq);
  83         int group, pend_offset, mask_offset;
  84         unsigned int pend, mask;
  85
  86         struct irq_chip *chip = irq_get_chip(irq);
  87         chained_irq_enter(chip, desc);
  88
  89         for (group = 0; group < bank->nr_groups; group++) {
  90                 struct samsung_gpio_chip *chip = bank->chips[group];
  91                 if (!chip)
  92                         continue;
  93
  94                 pend_offset = REG_OFFSET(group);
  95                 pend = __raw_readl(GPIO_BASE(chip) + PEND_OFFSET + pend_offset);
  96                 if (!pend)
  97                         continue;
  98
  99                 mask_offset = REG_OFFSET(group);
 100                 mask = __raw_readl(GPIO_BASE(chip) + MASK_OFFSET + mask_offset);
 101                 pend &= ~mask;
 102
 103                 while (pend) {
 104                         int offset = fls(pend) - 1;
 105                         int real_irq = chip->irq_base + offset;
 106                         generic_handle_irq(real_irq);
 107                         pend &= ~BIT(offset);
 108                 }
 109         }
 110         chained_irq_exit(chip, desc);
 111 }
 112
 113 static __init int s5p_gpioint_add(struct samsung_gpio_chip *chip)
 114 {
 115         static int used_gpioint_groups = 0;
 116         int group = chip->group;
 117         struct s5p_gpioint_bank *b, *bank = NULL;
 118         struct irq_chip_generic *gc;
 119         struct irq_chip_type *ct;
 120
 121         if (used_gpioint_groups >= S5P_GPIOINT_GROUP_COUNT)
 122                 return -ENOMEM;
 123
 124         list_for_each_entry(b, &banks, list) {
 125                 if (group >= b->start && group < b->start + b->nr_groups) {
 126                         bank = b;
 127                         break;
 128                 }
 129         }
 130         if (!bank)
 131                 return -EINVAL;
 132
 133         if (!bank->handler) {
 134                 bank->chips = kzalloc(sizeof(struct samsung_gpio_chip *) *
 135                                       bank->nr_groups, GFP_KERNEL);
 136                 if (!bank->chips)
 137                         return -ENOMEM;
 138
 139                 irq_set_chained_handler(bank->irq, s5p_gpioint_handler);
 140                 irq_set_handler_data(bank->irq, bank);
 141                 bank->handler = s5p_gpioint_handler;
 142                 printk(KERN_INFO "Registered chained gpio int handler for interrupt %d.\n",
 143                        bank->irq);
 144         }
 145
 146         /*
 147          * chained GPIO irq has been successfully registered, allocate new gpio
 148          * int group and assign irq nubmers
 149          */
 150         chip->irq_base = S5P_GPIOINT_BASE +
 151                          used_gpioint_groups * S5P_GPIOINT_GROUP_SIZE;
 152         used_gpioint_groups++;
 153
 154         bank->chips[group - bank->start] = chip;
 155
 156         gc = irq_alloc_generic_chip("s5p_gpioint", 1, chip->irq_base,
 157                                     (void __iomem *)GPIO_BASE(chip),
 158                                     handle_level_irq);
 159         if (!gc)
 160                 return -ENOMEM;
 161         ct = gc->chip_types;
 162         ct->chip.irq_ack = irq_gc_ack_set_bit;
 163         ct->chip.irq_mask = irq_gc_mask_set_bit;
 164         ct->chip.irq_unmask = irq_gc_mask_clr_bit;
 165         ct->chip.irq_set_type = s5p_gpioint_set_type,
 166         ct->regs.ack = PEND_OFFSET + REG_OFFSET(group - bank->start);
 167         ct->regs.mask = MASK_OFFSET + REG_OFFSET(group - bank->start);
 168         ct->regs.type = CON_OFFSET + REG_OFFSET(group - bank->start);
 169         irq_setup_generic_chip(gc, IRQ_MSK(chip->chip.ngpio),
 170                                IRQ_GC_INIT_MASK_CACHE,
 171                                IRQ_NOREQUEST | IRQ_NOPROBE, 0);
 172         return 0;
 173 }
 174
 175 int __init s5p_register_gpio_interrupt(int pin)
 176 {
 177         struct samsung_gpio_chip *my_chip = samsung_gpiolib_getchip(pin);
 178         int offset, group;
 179         int ret;
 180
 181         if (!my_chip)
 182                 return -EINVAL;
 183
 184         offset = pin - my_chip->chip.base;
 185         group = my_chip->group;
 186
 187         /* check if the group has been already registered */
 188         if (my_chip->irq_base)
 189                 return my_chip->irq_base + offset;
 190
 191         /* register gpio group */
 192         ret = s5p_gpioint_add(my_chip);
 193         if (ret == 0) {
 194                 my_chip->chip.to_irq = samsung_gpiolib_to_irq;
 195                 printk(KERN_INFO "Registered interrupt support for gpio group %d.\n",
 196                        group);
 197                 return my_chip->irq_base + offset;
 198         }
 199         return ret;
 200 }
 201
 202 int __init s5p_register_gpioint_bank(int chain_irq, int start, int nr_groups)
 203 {
 204         struct s5p_gpioint_bank *bank;
 205
 206         bank = kzalloc(sizeof(*bank), GFP_KERNEL);
 207         if (!bank)
 208                 return -ENOMEM;
 209
 210         bank->start = start;
 211         bank->nr_groups = nr_groups;
 212         bank->irq = chain_irq;
 213
 214         list_add_tail(&bank->list, &banks);
 215         return 0;
 216 }