drivers/gpio/gpio-sa1100.c

   1 /*
   2  * linux/arch/arm/mach-sa1100/gpio.c
   3  *
   4  * Generic SA-1100 GPIO handling
   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 version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10 #include <linux/gpio.h>
  11 #include <linux/init.h>
  12 #include <linux/module.h>
  13 #include <linux/io.h>
  14 #include <linux/syscore_ops.h>
  15 #include <mach/hardware.h>
  16 #include <mach/irqs.h>
  17
  18 static int sa1100_gpio_get(struct gpio_chip *chip, unsigned offset)
  19 {
  20         return !!(GPLR & GPIO_GPIO(offset));
  21 }
  22
  23 static void sa1100_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
  24 {
  25         if (value)
  26                 GPSR = GPIO_GPIO(offset);
  27         else
  28                 GPCR = GPIO_GPIO(offset);
  29 }
  30
  31 static int sa1100_direction_input(struct gpio_chip *chip, unsigned offset)
  32 {
  33         unsigned long flags;
  34
  35         local_irq_save(flags);
  36         GPDR &= ~GPIO_GPIO(offset);
  37         local_irq_restore(flags);
  38         return 0;
  39 }
  40
  41 static int sa1100_direction_output(struct gpio_chip *chip, unsigned offset, int value)
  42 {
  43         unsigned long flags;
  44
  45         local_irq_save(flags);
  46         sa1100_gpio_set(chip, offset, value);
  47         GPDR |= GPIO_GPIO(offset);
  48         local_irq_restore(flags);
  49         return 0;
  50 }
  51
  52 static int sa1100_to_irq(struct gpio_chip *chip, unsigned offset)
  53 {
  54         return IRQ_GPIO0 + offset;
  55 }
  56
  57 static struct gpio_chip sa1100_gpio_chip = {
  58         .label                  = "gpio",
  59         .direction_input        = sa1100_direction_input,
  60         .direction_output       = sa1100_direction_output,
  61         .set                    = sa1100_gpio_set,
  62         .get                    = sa1100_gpio_get,
  63         .to_irq                 = sa1100_to_irq,
  64         .base                   = 0,
  65         .ngpio                  = GPIO_MAX + 1,
  66 };
  67
  68 /*
  69  * SA1100 GPIO edge detection for IRQs:
  70  * IRQs are generated on Falling-Edge, Rising-Edge, or both.
  71  * Use this instead of directly setting GRER/GFER.
  72  */
  73 static int GPIO_IRQ_rising_edge;
  74 static int GPIO_IRQ_falling_edge;
  75 static int GPIO_IRQ_mask;
  76
  77 static int sa1100_gpio_type(struct irq_data *d, unsigned int type)
  78 {
  79         unsigned int mask;
  80
  81         mask = BIT(d->hwirq);
  82
  83         if (type == IRQ_TYPE_PROBE) {
  84                 if ((GPIO_IRQ_rising_edge | GPIO_IRQ_falling_edge) & mask)
  85                         return 0;
  86                 type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
  87         }
  88
  89         if (type & IRQ_TYPE_EDGE_RISING)
  90                 GPIO_IRQ_rising_edge |= mask;
  91         else
  92                 GPIO_IRQ_rising_edge &= ~mask;
  93         if (type & IRQ_TYPE_EDGE_FALLING)
  94                 GPIO_IRQ_falling_edge |= mask;
  95         else
  96                 GPIO_IRQ_falling_edge &= ~mask;
  97
  98         GRER = GPIO_IRQ_rising_edge & GPIO_IRQ_mask;
  99         GFER = GPIO_IRQ_falling_edge & GPIO_IRQ_mask;
 100
 101         return 0;
 102 }
 103
 104 /*
 105  * GPIO IRQs must be acknowledged.
 106  */
 107 static void sa1100_gpio_ack(struct irq_data *d)
 108 {
 109         GEDR = BIT(d->hwirq);
 110 }
 111
 112 static void sa1100_gpio_mask(struct irq_data *d)
 113 {
 114         unsigned int mask = BIT(d->hwirq);
 115
 116         GPIO_IRQ_mask &= ~mask;
 117
 118         GRER &= ~mask;
 119         GFER &= ~mask;
 120 }
 121
 122 static void sa1100_gpio_unmask(struct irq_data *d)
 123 {
 124         unsigned int mask = BIT(d->hwirq);
 125
 126         GPIO_IRQ_mask |= mask;
 127
 128         GRER = GPIO_IRQ_rising_edge & GPIO_IRQ_mask;
 129         GFER = GPIO_IRQ_falling_edge & GPIO_IRQ_mask;
 130 }
 131
 132 static int sa1100_gpio_wake(struct irq_data *d, unsigned int on)
 133 {
 134         if (on)
 135                 PWER |= BIT(d->hwirq);
 136         else
 137                 PWER &= ~BIT(d->hwirq);
 138         return 0;
 139 }
 140
 141 /*
 142  * This is for GPIO IRQs
 143  */
 144 static struct irq_chip sa1100_gpio_irq_chip = {
 145         .name           = "GPIO",
 146         .irq_ack        = sa1100_gpio_ack,
 147         .irq_mask       = sa1100_gpio_mask,
 148         .irq_unmask     = sa1100_gpio_unmask,
 149         .irq_set_type   = sa1100_gpio_type,
 150         .irq_set_wake   = sa1100_gpio_wake,
 151 };
 152
 153 static int sa1100_gpio_irqdomain_map(struct irq_domain *d,
 154                 unsigned int irq, irq_hw_number_t hwirq)
 155 {
 156         irq_set_chip_and_handler(irq, &sa1100_gpio_irq_chip,
 157                                  handle_edge_irq);
 158         irq_set_noprobe(irq);
 159
 160         return 0;
 161 }
 162
 163 static const struct irq_domain_ops sa1100_gpio_irqdomain_ops = {
 164         .map = sa1100_gpio_irqdomain_map,
 165         .xlate = irq_domain_xlate_onetwocell,
 166 };
 167
 168 static struct irq_domain *sa1100_gpio_irqdomain;
 169
 170 /*
 171  * IRQ 0-11 (GPIO) handler.  We enter here with the
 172  * irq_controller_lock held, and IRQs disabled.  Decode the IRQ
 173  * and call the handler.
 174  */
 175 static void sa1100_gpio_handler(struct irq_desc *desc)
 176 {
 177         unsigned int irq, mask;
 178
 179         mask = GEDR;
 180         do {
 181                 /*
 182                  * clear down all currently active IRQ sources.
 183                  * We will be processing them all.
 184                  */
 185                 GEDR = mask;
 186
 187                 irq = IRQ_GPIO0;
 188                 do {
 189                         if (mask & 1)
 190                                 generic_handle_irq(irq);
 191                         mask >>= 1;
 192                         irq++;
 193                 } while (mask);
 194
 195                 mask = GEDR;
 196         } while (mask);
 197 }
 198
 199 static int sa1100_gpio_suspend(void)
 200 {
 201         /*
 202          * Set the appropriate edges for wakeup.
 203          */
 204         GRER = PWER & GPIO_IRQ_rising_edge;
 205         GFER = PWER & GPIO_IRQ_falling_edge;
 206
 207         /*
 208          * Clear any pending GPIO interrupts.
 209          */
 210         GEDR = GEDR;
 211
 212         return 0;
 213 }
 214
 215 static void sa1100_gpio_resume(void)
 216 {
 217         GRER = GPIO_IRQ_rising_edge & GPIO_IRQ_mask;
 218         GFER = GPIO_IRQ_falling_edge & GPIO_IRQ_mask;
 219 }
 220
 221 static struct syscore_ops sa1100_gpio_syscore_ops = {
 222         .suspend        = sa1100_gpio_suspend,
 223         .resume         = sa1100_gpio_resume,
 224 };
 225
 226 static int __init sa1100_gpio_init_devicefs(void)
 227 {
 228         register_syscore_ops(&sa1100_gpio_syscore_ops);
 229         return 0;
 230 }
 231
 232 device_initcall(sa1100_gpio_init_devicefs);
 233
 234 void __init sa1100_init_gpio(void)
 235 {
 236         /* clear all GPIO edge detects */
 237         GFER = 0;
 238         GRER = 0;
 239         GEDR = -1;
 240
 241         gpiochip_add_data(&sa1100_gpio_chip, NULL);
 242
 243         sa1100_gpio_irqdomain = irq_domain_add_simple(NULL,
 244                         28, IRQ_GPIO0,
 245                         &sa1100_gpio_irqdomain_ops, NULL);
 246
 247         /*
 248          * Install handlers for GPIO 0-10 edge detect interrupts
 249          */
 250         irq_set_chained_handler(IRQ_GPIO0_SC, sa1100_gpio_handler);
 251         irq_set_chained_handler(IRQ_GPIO1_SC, sa1100_gpio_handler);
 252         irq_set_chained_handler(IRQ_GPIO2_SC, sa1100_gpio_handler);
 253         irq_set_chained_handler(IRQ_GPIO3_SC, sa1100_gpio_handler);
 254         irq_set_chained_handler(IRQ_GPIO4_SC, sa1100_gpio_handler);
 255         irq_set_chained_handler(IRQ_GPIO5_SC, sa1100_gpio_handler);
 256         irq_set_chained_handler(IRQ_GPIO6_SC, sa1100_gpio_handler);
 257         irq_set_chained_handler(IRQ_GPIO7_SC, sa1100_gpio_handler);
 258         irq_set_chained_handler(IRQ_GPIO8_SC, sa1100_gpio_handler);
 259         irq_set_chained_handler(IRQ_GPIO9_SC, sa1100_gpio_handler);
 260         irq_set_chained_handler(IRQ_GPIO10_SC, sa1100_gpio_handler);
 261         /*
 262          * Install handler for GPIO 11-27 edge detect interrupts
 263          */
 264         irq_set_chained_handler(IRQ_GPIO11_27, sa1100_gpio_handler);
 265
 266 }