arch/m68k/platform/coldfire/gpio.c

   1 /*
   2  * Coldfire generic GPIO support.
   3  *
   4  * (C) Copyright 2009, Steven King <sfking@fdwdc.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; version 2 of the License.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #include <linux/kernel.h>
  17 #include <linux/init.h>
  18 #include <linux/device.h>
  19
  20 #include <asm/gpio.h>
  21 #include <asm/pinmux.h>
  22 #include <asm/mcfgpio.h>
  23
  24 #define MCF_CHIP(chip) container_of(chip, struct mcf_gpio_chip, gpio_chip)
  25
  26 int mcf_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
  27 {
  28         unsigned long flags;
  29         MCFGPIO_PORTTYPE dir;
  30         struct mcf_gpio_chip *mcf_chip = MCF_CHIP(chip);
  31
  32         local_irq_save(flags);
  33         dir = mcfgpio_read(mcf_chip->pddr);
  34         dir &= ~mcfgpio_bit(chip->base + offset);
  35         mcfgpio_write(dir, mcf_chip->pddr);
  36         local_irq_restore(flags);
  37
  38         return 0;
  39 }
  40
  41 int mcf_gpio_get_value(struct gpio_chip *chip, unsigned offset)
  42 {
  43         struct mcf_gpio_chip *mcf_chip = MCF_CHIP(chip);
  44
  45         return mcfgpio_read(mcf_chip->ppdr) & mcfgpio_bit(chip->base + offset);
  46 }
  47
  48 int mcf_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
  49                 int value)
  50 {
  51         unsigned long flags;
  52         MCFGPIO_PORTTYPE data;
  53         struct mcf_gpio_chip *mcf_chip = MCF_CHIP(chip);
  54
  55         local_irq_save(flags);
  56         /* write the value to the output latch */
  57         data = mcfgpio_read(mcf_chip->podr);
  58         if (value)
  59                 data |= mcfgpio_bit(chip->base + offset);
  60         else
  61                 data &= ~mcfgpio_bit(chip->base + offset);
  62         mcfgpio_write(data, mcf_chip->podr);
  63
  64         /* now set the direction to output */
  65         data = mcfgpio_read(mcf_chip->pddr);
  66         data |= mcfgpio_bit(chip->base + offset);
  67         mcfgpio_write(data, mcf_chip->pddr);
  68         local_irq_restore(flags);
  69
  70         return 0;
  71 }
  72
  73 void mcf_gpio_set_value(struct gpio_chip *chip, unsigned offset, int value)
  74 {
  75         struct mcf_gpio_chip *mcf_chip = MCF_CHIP(chip);
  76
  77         unsigned long flags;
  78         MCFGPIO_PORTTYPE data;
  79
  80         local_irq_save(flags);
  81         data = mcfgpio_read(mcf_chip->podr);
  82         if (value)
  83                 data |= mcfgpio_bit(chip->base + offset);
  84         else
  85                 data &= ~mcfgpio_bit(chip->base + offset);
  86         mcfgpio_write(data, mcf_chip->podr);
  87         local_irq_restore(flags);
  88 }
  89
  90 void mcf_gpio_set_value_fast(struct gpio_chip *chip, unsigned offset, int value)
  91 {
  92         struct mcf_gpio_chip *mcf_chip = MCF_CHIP(chip);
  93
  94         if (value)
  95                 mcfgpio_write(mcfgpio_bit(chip->base + offset), mcf_chip->setr);
  96         else
  97                 mcfgpio_write(~mcfgpio_bit(chip->base + offset), mcf_chip->clrr);
  98 }
  99
 100 int mcf_gpio_request(struct gpio_chip *chip, unsigned offset)
 101 {
 102         struct mcf_gpio_chip *mcf_chip = MCF_CHIP(chip);
 103
 104         return mcf_chip->gpio_to_pinmux ?
 105                 mcf_pinmux_request(mcf_chip->gpio_to_pinmux[offset], 0) : 0;
 106 }
 107
 108 void mcf_gpio_free(struct gpio_chip *chip, unsigned offset)
 109 {
 110         struct mcf_gpio_chip *mcf_chip = MCF_CHIP(chip);
 111
 112         mcf_gpio_direction_input(chip, offset);
 113
 114         if (mcf_chip->gpio_to_pinmux)
 115                 mcf_pinmux_release(mcf_chip->gpio_to_pinmux[offset], 0);
 116 }
 117
 118 struct bus_type mcf_gpio_subsys = {
 119         .name           = "gpio",
 120         .dev_name       = "gpio",
 121 };
 122
 123 static int __init mcf_gpio_sysinit(void)
 124 {
 125         return subsys_system_register(&mcf_gpio_subsys, NULL);
 126 }
 127
 128 core_initcall(mcf_gpio_sysinit);