linux-stable-rt/arch/avr32/mach-at32ap/pio.c

413 lines
8.3 KiB
C

/*
* Atmel PIO2 Port Multiplexer support
*
* Copyright (C) 2004-2006 Atmel Corporation
*
* 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/clk.h>
#include <linux/debugfs.h>
#include <linux/fs.h>
#include <linux/platform_device.h>
#include <linux/irq.h>
#include <asm/gpio.h>
#include <asm/io.h>
#include <asm/arch/portmux.h>
#include "pio.h"
#define MAX_NR_PIO_DEVICES 8
struct pio_device {
void __iomem *regs;
const struct platform_device *pdev;
struct clk *clk;
u32 pinmux_mask;
u32 gpio_mask;
char name[8];
};
static struct pio_device pio_dev[MAX_NR_PIO_DEVICES];
static struct pio_device *gpio_to_pio(unsigned int gpio)
{
struct pio_device *pio;
unsigned int index;
index = gpio >> 5;
if (index >= MAX_NR_PIO_DEVICES)
return NULL;
pio = &pio_dev[index];
if (!pio->regs)
return NULL;
return pio;
}
/* Pin multiplexing API */
void __init at32_select_periph(unsigned int pin, unsigned int periph,
unsigned long flags)
{
struct pio_device *pio;
unsigned int pin_index = pin & 0x1f;
u32 mask = 1 << pin_index;
pio = gpio_to_pio(pin);
if (unlikely(!pio)) {
printk("pio: invalid pin %u\n", pin);
goto fail;
}
if (unlikely(test_and_set_bit(pin_index, &pio->pinmux_mask))) {
printk("%s: pin %u is busy\n", pio->name, pin_index);
goto fail;
}
pio_writel(pio, PUER, mask);
if (periph)
pio_writel(pio, BSR, mask);
else
pio_writel(pio, ASR, mask);
pio_writel(pio, PDR, mask);
if (!(flags & AT32_GPIOF_PULLUP))
pio_writel(pio, PUDR, mask);
/* gpio_request NOT allowed */
set_bit(pin_index, &pio->gpio_mask);
return;
fail:
dump_stack();
}
void __init at32_select_gpio(unsigned int pin, unsigned long flags)
{
struct pio_device *pio;
unsigned int pin_index = pin & 0x1f;
u32 mask = 1 << pin_index;
pio = gpio_to_pio(pin);
if (unlikely(!pio)) {
printk("pio: invalid pin %u\n", pin);
goto fail;
}
if (unlikely(test_and_set_bit(pin_index, &pio->pinmux_mask))) {
printk("%s: pin %u is busy\n", pio->name, pin_index);
goto fail;
}
if (flags & AT32_GPIOF_OUTPUT) {
if (flags & AT32_GPIOF_HIGH)
pio_writel(pio, SODR, mask);
else
pio_writel(pio, CODR, mask);
pio_writel(pio, PUDR, mask);
pio_writel(pio, OER, mask);
} else {
if (flags & AT32_GPIOF_PULLUP)
pio_writel(pio, PUER, mask);
else
pio_writel(pio, PUDR, mask);
if (flags & AT32_GPIOF_DEGLITCH)
pio_writel(pio, IFER, mask);
else
pio_writel(pio, IFDR, mask);
pio_writel(pio, ODR, mask);
}
pio_writel(pio, PER, mask);
/* gpio_request now allowed */
clear_bit(pin_index, &pio->gpio_mask);
return;
fail:
dump_stack();
}
/* Reserve a pin, preventing anyone else from changing its configuration. */
void __init at32_reserve_pin(unsigned int pin)
{
struct pio_device *pio;
unsigned int pin_index = pin & 0x1f;
pio = gpio_to_pio(pin);
if (unlikely(!pio)) {
printk("pio: invalid pin %u\n", pin);
goto fail;
}
if (unlikely(test_and_set_bit(pin_index, &pio->pinmux_mask))) {
printk("%s: pin %u is busy\n", pio->name, pin_index);
goto fail;
}
return;
fail:
dump_stack();
}
/*--------------------------------------------------------------------------*/
/* GPIO API */
int gpio_request(unsigned int gpio, const char *label)
{
struct pio_device *pio;
unsigned int pin;
pio = gpio_to_pio(gpio);
if (!pio)
return -ENODEV;
pin = gpio & 0x1f;
if (test_and_set_bit(pin, &pio->gpio_mask))
return -EBUSY;
return 0;
}
EXPORT_SYMBOL(gpio_request);
void gpio_free(unsigned int gpio)
{
struct pio_device *pio;
unsigned int pin;
pio = gpio_to_pio(gpio);
if (!pio) {
printk(KERN_ERR
"gpio: attempted to free invalid pin %u\n", gpio);
return;
}
pin = gpio & 0x1f;
if (!test_and_clear_bit(pin, &pio->gpio_mask))
printk(KERN_ERR "gpio: freeing free or non-gpio pin %s-%u\n",
pio->name, pin);
}
EXPORT_SYMBOL(gpio_free);
int gpio_direction_input(unsigned int gpio)
{
struct pio_device *pio;
unsigned int pin;
pio = gpio_to_pio(gpio);
if (!pio)
return -ENODEV;
pin = gpio & 0x1f;
pio_writel(pio, ODR, 1 << pin);
return 0;
}
EXPORT_SYMBOL(gpio_direction_input);
int gpio_direction_output(unsigned int gpio)
{
struct pio_device *pio;
unsigned int pin;
pio = gpio_to_pio(gpio);
if (!pio)
return -ENODEV;
pin = gpio & 0x1f;
pio_writel(pio, OER, 1 << pin);
return 0;
}
EXPORT_SYMBOL(gpio_direction_output);
int gpio_get_value(unsigned int gpio)
{
struct pio_device *pio = &pio_dev[gpio >> 5];
return (pio_readl(pio, PDSR) >> (gpio & 0x1f)) & 1;
}
EXPORT_SYMBOL(gpio_get_value);
void gpio_set_value(unsigned int gpio, int value)
{
struct pio_device *pio = &pio_dev[gpio >> 5];
u32 mask;
mask = 1 << (gpio & 0x1f);
if (value)
pio_writel(pio, SODR, mask);
else
pio_writel(pio, CODR, mask);
}
EXPORT_SYMBOL(gpio_set_value);
/*--------------------------------------------------------------------------*/
/* GPIO IRQ support */
static void gpio_irq_mask(unsigned irq)
{
unsigned gpio = irq_to_gpio(irq);
struct pio_device *pio = &pio_dev[gpio >> 5];
pio_writel(pio, IDR, 1 << (gpio & 0x1f));
}
static void gpio_irq_unmask(unsigned irq)
{
unsigned gpio = irq_to_gpio(irq);
struct pio_device *pio = &pio_dev[gpio >> 5];
pio_writel(pio, IER, 1 << (gpio & 0x1f));
}
static int gpio_irq_type(unsigned irq, unsigned type)
{
if (type != IRQ_TYPE_EDGE_BOTH && type != IRQ_TYPE_NONE)
return -EINVAL;
return 0;
}
static struct irq_chip gpio_irqchip = {
.name = "gpio",
.mask = gpio_irq_mask,
.unmask = gpio_irq_unmask,
.set_type = gpio_irq_type,
};
static void gpio_irq_handler(unsigned irq, struct irq_desc *desc)
{
struct pio_device *pio = get_irq_chip_data(irq);
unsigned gpio_irq;
gpio_irq = (unsigned) get_irq_data(irq);
for (;;) {
u32 isr;
struct irq_desc *d;
/* ack pending GPIO interrupts */
isr = pio_readl(pio, ISR) & pio_readl(pio, IMR);
if (!isr)
break;
do {
int i;
i = ffs(isr) - 1;
isr &= ~(1 << i);
i += gpio_irq;
d = &irq_desc[i];
d->handle_irq(i, d);
} while (isr);
}
}
static void __init
gpio_irq_setup(struct pio_device *pio, int irq, int gpio_irq)
{
unsigned i;
set_irq_chip_data(irq, pio);
set_irq_data(irq, (void *) gpio_irq);
for (i = 0; i < 32; i++, gpio_irq++) {
set_irq_chip_data(gpio_irq, pio);
set_irq_chip_and_handler(gpio_irq, &gpio_irqchip,
handle_simple_irq);
}
set_irq_chained_handler(irq, gpio_irq_handler);
}
/*--------------------------------------------------------------------------*/
static int __init pio_probe(struct platform_device *pdev)
{
struct pio_device *pio = NULL;
int irq = platform_get_irq(pdev, 0);
int gpio_irq_base = GPIO_IRQ_BASE + pdev->id * 32;
BUG_ON(pdev->id >= MAX_NR_PIO_DEVICES);
pio = &pio_dev[pdev->id];
BUG_ON(!pio->regs);
gpio_irq_setup(pio, irq, gpio_irq_base);
platform_set_drvdata(pdev, pio);
printk(KERN_DEBUG "%s: base 0x%p, irq %d chains %d..%d\n",
pio->name, pio->regs, irq, gpio_irq_base, gpio_irq_base + 31);
return 0;
}
static struct platform_driver pio_driver = {
.probe = pio_probe,
.driver = {
.name = "pio",
},
};
static int __init pio_init(void)
{
return platform_driver_register(&pio_driver);
}
postcore_initcall(pio_init);
void __init at32_init_pio(struct platform_device *pdev)
{
struct resource *regs;
struct pio_device *pio;
if (pdev->id > MAX_NR_PIO_DEVICES) {
dev_err(&pdev->dev, "only %d PIO devices supported\n",
MAX_NR_PIO_DEVICES);
return;
}
pio = &pio_dev[pdev->id];
snprintf(pio->name, sizeof(pio->name), "pio%d", pdev->id);
regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!regs) {
dev_err(&pdev->dev, "no mmio resource defined\n");
return;
}
pio->clk = clk_get(&pdev->dev, "mck");
if (IS_ERR(pio->clk))
/*
* This is a fatal error, but if we continue we might
* be so lucky that we manage to initialize the
* console and display this message...
*/
dev_err(&pdev->dev, "no mck clock defined\n");
else
clk_enable(pio->clk);
pio->pdev = pdev;
pio->regs = ioremap(regs->start, regs->end - regs->start + 1);
/*
* request_gpio() is only valid for pins that have been
* explicitly configured as GPIO and not previously requested
*/
pio->gpio_mask = ~0UL;
/* start with irqs disabled and acked */
pio_writel(pio, IDR, ~0UL);
(void) pio_readl(pio, ISR);
}