Logo Search packages:      
Sourcecode: linux version File versions  Download package

ext-gpio.c

/*
 * GPIOLIB interface for BF538/9 PORT C, D, and E GPIOs
 *
 * Copyright 2009 Analog Devices Inc.
 *
 * Licensed under the GPL-2 or later.
 */

#include <linux/module.h>
#include <linux/err.h>
#include <asm/blackfin.h>
#include <asm/gpio.h>
#include <asm/portmux.h>

#define DEFINE_REG(reg, off) \
static inline u16 read_##reg(void __iomem *port) \
      { return bfin_read16(port + off); } \
static inline void write_##reg(void __iomem *port, u16 v) \
      { bfin_write16(port + off, v); }

DEFINE_REG(PORTIO, 0x00)
DEFINE_REG(PORTIO_CLEAR, 0x10)
DEFINE_REG(PORTIO_SET, 0x20)
DEFINE_REG(PORTIO_DIR, 0x40)
DEFINE_REG(PORTIO_INEN, 0x50)

static void __iomem *gpio_chip_to_mmr(struct gpio_chip *chip)
{
      switch (chip->base) {
      default: /* not really needed, but keeps gcc happy */
      case GPIO_PC0: return (void __iomem *)PORTCIO;
      case GPIO_PD0: return (void __iomem *)PORTDIO;
      case GPIO_PE0: return (void __iomem *)PORTEIO;
      }
}

static int bf538_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
{
      void __iomem *port = gpio_chip_to_mmr(chip);
      return !!(read_PORTIO(port) & (1u << gpio));
}

static void bf538_gpio_set_value(struct gpio_chip *chip, unsigned gpio, int value)
{
      void __iomem *port = gpio_chip_to_mmr(chip);
      if (value)
            write_PORTIO_SET(port, (1u << gpio));
      else
            write_PORTIO_CLEAR(port, (1u << gpio));
}

static int bf538_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
{
      void __iomem *port = gpio_chip_to_mmr(chip);
      write_PORTIO_DIR(port, read_PORTIO_DIR(port) & ~(1u << gpio));
      write_PORTIO_INEN(port, read_PORTIO_INEN(port) | (1u << gpio));
      return 0;
}

static int bf538_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, int value)
{
      void __iomem *port = gpio_chip_to_mmr(chip);
      write_PORTIO_INEN(port, read_PORTIO_INEN(port) & ~(1u << gpio));
      bf538_gpio_set_value(port, gpio, value);
      write_PORTIO_DIR(port, read_PORTIO_DIR(port) | (1u << gpio));
      return 0;
}

static int bf538_gpio_request(struct gpio_chip *chip, unsigned gpio)
{
      return bfin_special_gpio_request(chip->base + gpio, chip->label);
}

static void bf538_gpio_free(struct gpio_chip *chip, unsigned gpio)
{
      return bfin_special_gpio_free(chip->base + gpio);
}

/* We don't set the irq fields as these banks cannot generate interrupts */

static struct gpio_chip bf538_portc_chip = {
      .label = "GPIO-PC",
      .direction_input = bf538_gpio_direction_input,
      .get = bf538_gpio_get_value,
      .direction_output = bf538_gpio_direction_output,
      .set = bf538_gpio_set_value,
      .request = bf538_gpio_request,
      .free = bf538_gpio_free,
      .base = GPIO_PC0,
      .ngpio = GPIO_PC9 - GPIO_PC0 + 1,
};

static struct gpio_chip bf538_portd_chip = {
      .label = "GPIO-PD",
      .direction_input = bf538_gpio_direction_input,
      .get = bf538_gpio_get_value,
      .direction_output = bf538_gpio_direction_output,
      .set = bf538_gpio_set_value,
      .request = bf538_gpio_request,
      .free = bf538_gpio_free,
      .base = GPIO_PD0,
      .ngpio = GPIO_PD13 - GPIO_PD0 + 1,
};

static struct gpio_chip bf538_porte_chip = {
      .label = "GPIO-PE",
      .direction_input = bf538_gpio_direction_input,
      .get = bf538_gpio_get_value,
      .direction_output = bf538_gpio_direction_output,
      .set = bf538_gpio_set_value,
      .request = bf538_gpio_request,
      .free = bf538_gpio_free,
      .base = GPIO_PE0,
      .ngpio = GPIO_PE15 - GPIO_PE0 + 1,
};

static int __init bf538_extgpio_setup(void)
{
      return gpiochip_add(&bf538_portc_chip) |
            gpiochip_add(&bf538_portd_chip) |
            gpiochip_add(&bf538_porte_chip);
}
arch_initcall(bf538_extgpio_setup);

Generated by  Doxygen 1.6.0   Back to index