release/src-rt-6.x.4708/linux/linux-2.6.36/arch/blackfin/mach-bf538/ext-gpio.c

   1 /*
   2  * GPIOLIB interface for BF538/9 PORT C, D, and E GPIOs
   3  *
   4  * Copyright 2009 Analog Devices Inc.
   5  *
   6  * Licensed under the GPL-2 or later.
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/err.h>
  11 #include <asm/blackfin.h>
  12 #include <asm/gpio.h>
  13 #include <asm/portmux.h>
  14
  15 #define DEFINE_REG(reg, off) \
  16 static inline u16 read_##reg(void __iomem *port) \
  17         { return bfin_read16(port + off); } \
  18 static inline void write_##reg(void __iomem *port, u16 v) \
  19         { bfin_write16(port + off, v); }
  20
  21 DEFINE_REG(PORTIO, 0x00)
  22 DEFINE_REG(PORTIO_CLEAR, 0x10)
  23 DEFINE_REG(PORTIO_SET, 0x20)
  24 DEFINE_REG(PORTIO_DIR, 0x40)
  25 DEFINE_REG(PORTIO_INEN, 0x50)
  26
  27 static void __iomem *gpio_chip_to_mmr(struct gpio_chip *chip)
  28 {
  29         switch (chip->base) {
  30         default: /* not really needed, but keeps gcc happy */
  31         case GPIO_PC0: return (void __iomem *)PORTCIO;
  32         case GPIO_PD0: return (void __iomem *)PORTDIO;
  33         case GPIO_PE0: return (void __iomem *)PORTEIO;
  34         }
  35 }
  36
  37 static int bf538_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
  38 {
  39         void __iomem *port = gpio_chip_to_mmr(chip);
  40         return !!(read_PORTIO(port) & (1u << gpio));
  41 }
  42
  43 static void bf538_gpio_set_value(struct gpio_chip *chip, unsigned gpio, int value)
  44 {
  45         void __iomem *port = gpio_chip_to_mmr(chip);
  46         if (value)
  47                 write_PORTIO_SET(port, (1u << gpio));
  48         else
  49                 write_PORTIO_CLEAR(port, (1u << gpio));
  50 }
  51
  52 static int bf538_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
  53 {
  54         void __iomem *port = gpio_chip_to_mmr(chip);
  55         write_PORTIO_DIR(port, read_PORTIO_DIR(port) & ~(1u << gpio));
  56         write_PORTIO_INEN(port, read_PORTIO_INEN(port) | (1u << gpio));
  57         return 0;
  58 }
  59
  60 static int bf538_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, int value)
  61 {
  62         void __iomem *port = gpio_chip_to_mmr(chip);
  63         write_PORTIO_INEN(port, read_PORTIO_INEN(port) & ~(1u << gpio));
  64         bf538_gpio_set_value(port, gpio, value);
  65         write_PORTIO_DIR(port, read_PORTIO_DIR(port) | (1u << gpio));
  66         return 0;
  67 }
  68
  69 static int bf538_gpio_request(struct gpio_chip *chip, unsigned gpio)
  70 {
  71         return bfin_special_gpio_request(chip->base + gpio, chip->label);
  72 }
  73
  74 static void bf538_gpio_free(struct gpio_chip *chip, unsigned gpio)
  75 {
  76         return bfin_special_gpio_free(chip->base + gpio);
  77 }
  78
  79 /* We don't set the irq fields as these banks cannot generate interrupts */
  80
  81 static struct gpio_chip bf538_portc_chip = {
  82         .label = "GPIO-PC",
  83         .direction_input = bf538_gpio_direction_input,
  84         .get = bf538_gpio_get_value,
  85         .direction_output = bf538_gpio_direction_output,
  86         .set = bf538_gpio_set_value,
  87         .request = bf538_gpio_request,
  88         .free = bf538_gpio_free,
  89         .base = GPIO_PC0,
  90         .ngpio = GPIO_PC9 - GPIO_PC0 + 1,
  91 };
  92
  93 static struct gpio_chip bf538_portd_chip = {
  94         .label = "GPIO-PD",
  95         .direction_input = bf538_gpio_direction_input,
  96         .get = bf538_gpio_get_value,
  97         .direction_output = bf538_gpio_direction_output,
  98         .set = bf538_gpio_set_value,
  99         .request = bf538_gpio_request,
 100         .free = bf538_gpio_free,
 101         .base = GPIO_PD0,
 102         .ngpio = GPIO_PD13 - GPIO_PD0 + 1,
 103 };
 104
 105 static struct gpio_chip bf538_porte_chip = {
 106         .label = "GPIO-PE",
 107         .direction_input = bf538_gpio_direction_input,
 108         .get = bf538_gpio_get_value,
 109         .direction_output = bf538_gpio_direction_output,
 110         .set = bf538_gpio_set_value,
 111         .request = bf538_gpio_request,
 112         .free = bf538_gpio_free,
 113         .base = GPIO_PE0,
 114         .ngpio = GPIO_PE15 - GPIO_PE0 + 1,
 115 };
 116
 117 static int __init bf538_extgpio_setup(void)
 118 {
 119         return gpiochip_add(&bf538_portc_chip) |
 120                 gpiochip_add(&bf538_portd_chip) |
 121                 gpiochip_add(&bf538_porte_chip);
 122 }
 123 arch_initcall(bf538_extgpio_setup);