blob: 6478eb10691aafcc85ef4290fe1780802ef0025d [file] [log] [blame]
/*
* GPIOs on MPC8349/8572/8610 and compatible
*
* Copyright (C) 2008 Peter Korsgaard <jacmet@sunsite.dk>
*
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/gpio.h>
#include <linux/slab.h>
#define MPC8XXX_GPIO_PINS 32
#define GPIO_DIR 0x00
#define GPIO_ODR 0x04
#define GPIO_DAT 0x08
#define GPIO_IER 0x0c
#define GPIO_IMR 0x10
#define GPIO_ICR 0x14
struct mpc8xxx_gpio_chip {
struct of_mm_gpio_chip mm_gc;
spinlock_t lock;
/*
* shadowed data register to be able to clear/set output pins in
* open drain mode safely
*/
u32 data;
};
static inline u32 mpc8xxx_gpio2mask(unsigned int gpio)
{
return 1u << (MPC8XXX_GPIO_PINS - 1 - gpio);
}
static inline struct mpc8xxx_gpio_chip *
to_mpc8xxx_gpio_chip(struct of_mm_gpio_chip *mm)
{
return container_of(mm, struct mpc8xxx_gpio_chip, mm_gc);
}
static void mpc8xxx_gpio_save_regs(struct of_mm_gpio_chip *mm)
{
struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
mpc8xxx_gc->data = in_be32(mm->regs + GPIO_DAT);
}
/* Workaround GPIO 1 errata on MPC8572/MPC8536. The status of GPIOs
* defined as output cannot be determined by reading GPDAT register,
* so we use shadow data register instead. The status of input pins
* is determined by reading GPDAT register.
*/
static int mpc8572_gpio_get(struct gpio_chip *gc, unsigned int gpio)
{
u32 val;
struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
val = in_be32(mm->regs + GPIO_DAT) & ~in_be32(mm->regs + GPIO_DIR);
return (val | mpc8xxx_gc->data) & mpc8xxx_gpio2mask(gpio);
}
static int mpc8xxx_gpio_get(struct gpio_chip *gc, unsigned int gpio)
{
struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
return in_be32(mm->regs + GPIO_DAT) & mpc8xxx_gpio2mask(gpio);
}
static void mpc8xxx_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
{
struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
unsigned long flags;
spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
if (val)
mpc8xxx_gc->data |= mpc8xxx_gpio2mask(gpio);
else
mpc8xxx_gc->data &= ~mpc8xxx_gpio2mask(gpio);
out_be32(mm->regs + GPIO_DAT, mpc8xxx_gc->data);
spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
}
static int mpc8xxx_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
{
struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
unsigned long flags;
spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
clrbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio));
spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
return 0;
}
static int mpc8xxx_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
{
struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
unsigned long flags;
mpc8xxx_gpio_set(gc, gpio, val);
spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
setbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio));
spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
return 0;
}
static void __init mpc8xxx_add_controller(struct device_node *np)
{
struct mpc8xxx_gpio_chip *mpc8xxx_gc;
struct of_mm_gpio_chip *mm_gc;
struct of_gpio_chip *of_gc;
struct gpio_chip *gc;
int ret;
mpc8xxx_gc = kzalloc(sizeof(*mpc8xxx_gc), GFP_KERNEL);
if (!mpc8xxx_gc) {
ret = -ENOMEM;
goto err;
}
spin_lock_init(&mpc8xxx_gc->lock);
mm_gc = &mpc8xxx_gc->mm_gc;
of_gc = &mm_gc->of_gc;
gc = &of_gc->gc;
mm_gc->save_regs = mpc8xxx_gpio_save_regs;
of_gc->gpio_cells = 2;
gc->ngpio = MPC8XXX_GPIO_PINS;
gc->direction_input = mpc8xxx_gpio_dir_in;
gc->direction_output = mpc8xxx_gpio_dir_out;
if (of_device_is_compatible(np, "fsl,mpc8572-gpio"))
gc->get = mpc8572_gpio_get;
else
gc->get = mpc8xxx_gpio_get;
gc->set = mpc8xxx_gpio_set;
ret = of_mm_gpiochip_add(np, mm_gc);
if (ret)
goto err;
return;
err:
pr_err("%s: registration failed with status %d\n",
np->full_name, ret);
kfree(mpc8xxx_gc);
return;
}
static int __init mpc8xxx_add_gpiochips(void)
{
struct device_node *np;
for_each_compatible_node(np, NULL, "fsl,mpc8349-gpio")
mpc8xxx_add_controller(np);
for_each_compatible_node(np, NULL, "fsl,mpc8572-gpio")
mpc8xxx_add_controller(np);
for_each_compatible_node(np, NULL, "fsl,mpc8610-gpio")
mpc8xxx_add_controller(np);
return 0;
}
arch_initcall(mpc8xxx_add_gpiochips);