linux/arch/arm/mach-ep93xx/gpio.c
Ryan Mallon b685004f8d [ARM] 4988/1: Add GPIO lib support to the EP93xx
Adds support for the generic GPIO lib to the EP93xx family. The gpio
handling code has been moved from core.c to a new file called gpio.c.
The GPIO based IRQ code has not been changed.

Signed-off-by: Ryan Mallon <ryan@bluewatersys.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-04-19 14:01:43 +01:00

158 lines
3.9 KiB
C

/*
* linux/arch/arm/mach-ep93xx/gpio.c
*
* Generic EP93xx GPIO handling
*
* Copyright (c) 2008 Ryan Mallon <ryan@bluewatersys.com>
*
* Based on code originally from:
* linux/arch/arm/mach-ep93xx/core.c
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <asm/arch/ep93xx-regs.h>
#include <asm/io.h>
#include <asm/gpio.h>
struct ep93xx_gpio_chip {
struct gpio_chip chip;
unsigned int data_reg;
unsigned int data_dir_reg;
};
#define to_ep93xx_gpio_chip(c) container_of(c, struct ep93xx_gpio_chip, chip)
/* From core.c */
extern void ep93xx_gpio_int_mask(unsigned line);
extern void ep93xx_gpio_update_int_params(unsigned port);
static int ep93xx_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
unsigned long flags;
u8 v;
local_irq_save(flags);
v = __raw_readb(ep93xx_chip->data_dir_reg);
v &= ~(1 << offset);
__raw_writeb(v, ep93xx_chip->data_dir_reg);
local_irq_restore(flags);
return 0;
}
static int ep93xx_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int val)
{
struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
unsigned long flags;
int line;
u8 v;
local_irq_save(flags);
/* Set the value */
v = __raw_readb(ep93xx_chip->data_reg);
if (val)
v |= (1 << offset);
else
v &= ~(1 << offset);
__raw_writeb(v, ep93xx_chip->data_reg);
/* Drive as an output */
line = chip->base + offset;
if (line <= EP93XX_GPIO_LINE_MAX_IRQ) {
/* Ports A/B/F */
ep93xx_gpio_int_mask(line);
ep93xx_gpio_update_int_params(line >> 3);
}
v = __raw_readb(ep93xx_chip->data_dir_reg);
v |= (1 << offset);
__raw_writeb(v, ep93xx_chip->data_dir_reg);
local_irq_restore(flags);
return 0;
}
static int ep93xx_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
return !!(__raw_readb(ep93xx_chip->data_reg) & (1 << offset));
}
static void ep93xx_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
{
struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
unsigned long flags;
u8 v;
local_irq_save(flags);
v = __raw_readb(ep93xx_chip->data_reg);
if (val)
v |= (1 << offset);
else
v &= ~(1 << offset);
__raw_writeb(v, ep93xx_chip->data_reg);
local_irq_restore(flags);
}
static void ep93xx_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
u8 data_reg, data_dir_reg;
int i;
data_reg = __raw_readb(ep93xx_chip->data_reg);
data_dir_reg = __raw_readb(ep93xx_chip->data_dir_reg);
for (i = 0; i < chip->ngpio; i++)
seq_printf(s, "GPIO %s%d: %s %s\n", chip->label, i,
(data_reg & (1 << i)) ? "set" : "clear",
(data_dir_reg & (1 << i)) ? "out" : "in");
}
#define EP93XX_GPIO_BANK(name, dr, ddr, base_gpio) \
{ \
.chip = { \
.label = name, \
.direction_input = ep93xx_gpio_direction_input, \
.direction_output = ep93xx_gpio_direction_output, \
.get = ep93xx_gpio_get, \
.set = ep93xx_gpio_set, \
.dbg_show = ep93xx_gpio_dbg_show, \
.base = base_gpio, \
.ngpio = 8, \
}, \
.data_reg = EP93XX_GPIO_REG(dr), \
.data_dir_reg = EP93XX_GPIO_REG(ddr), \
}
static struct ep93xx_gpio_chip ep93xx_gpio_banks[] = {
EP93XX_GPIO_BANK("A", 0x00, 0x10, 0),
EP93XX_GPIO_BANK("B", 0x04, 0x14, 8),
EP93XX_GPIO_BANK("C", 0x30, 0x34, 40),
EP93XX_GPIO_BANK("D", 0x0c, 0x1c, 24),
EP93XX_GPIO_BANK("E", 0x20, 0x24, 32),
EP93XX_GPIO_BANK("F", 0x08, 0x18, 16),
EP93XX_GPIO_BANK("G", 0x38, 0x3c, 48),
EP93XX_GPIO_BANK("H", 0x40, 0x44, 56),
};
void __init ep93xx_gpio_init(void)
{
int i;
for (i = 0; i < ARRAY_SIZE(ep93xx_gpio_banks); i++)
gpiochip_add(&ep93xx_gpio_banks[i].chip);
}