linux/arch/arm/mach-pxa/gpio.c

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/*
* linux/arch/arm/mach-pxa/gpio.c
*
* Generic PXA GPIO handling
*
* Author: Nicolas Pitre
* Created: Jun 15, 2001
* Copyright: MontaVista Software Inc.
*
* 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/irq.h>
#include <linux/sysdev.h>
#include <linux/io.h>
#include <asm/gpio.h>
#include <mach/hardware.h>
#include <mach/pxa-regs.h>
#include <mach/pxa2xx-gpio.h>
#include "generic.h"
struct pxa_gpio_chip {
struct gpio_chip chip;
void __iomem *regbase;
};
int pxa_last_gpio;
/*
* Configure pins for GPIO or other functions
*/
int pxa_gpio_mode(int gpio_mode)
{
unsigned long flags;
int gpio = gpio_mode & GPIO_MD_MASK_NR;
int fn = (gpio_mode & GPIO_MD_MASK_FN) >> 8;
int gafr;
if (gpio > pxa_last_gpio)
return -EINVAL;
local_irq_save(flags);
if (gpio_mode & GPIO_DFLT_LOW)
GPCR(gpio) = GPIO_bit(gpio);
else if (gpio_mode & GPIO_DFLT_HIGH)
GPSR(gpio) = GPIO_bit(gpio);
if (gpio_mode & GPIO_MD_MASK_DIR)
GPDR(gpio) |= GPIO_bit(gpio);
else
GPDR(gpio) &= ~GPIO_bit(gpio);
gafr = GAFR(gpio) & ~(0x3 << (((gpio) & 0xf)*2));
GAFR(gpio) = gafr | (fn << (((gpio) & 0xf)*2));
local_irq_restore(flags);
return 0;
}
EXPORT_SYMBOL(pxa_gpio_mode);
static int pxa_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
unsigned long flags;
u32 mask = 1 << offset;
u32 value;
struct pxa_gpio_chip *pxa;
void __iomem *gpdr;
pxa = container_of(chip, struct pxa_gpio_chip, chip);
gpdr = pxa->regbase + GPDR_OFFSET;
local_irq_save(flags);
value = __raw_readl(gpdr);
value &= ~mask;
__raw_writel(value, gpdr);
local_irq_restore(flags);
return 0;
}
static int pxa_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int value)
{
unsigned long flags;
u32 mask = 1 << offset;
u32 tmp;
struct pxa_gpio_chip *pxa;
void __iomem *gpdr;
pxa = container_of(chip, struct pxa_gpio_chip, chip);
__raw_writel(mask,
pxa->regbase + (value ? GPSR_OFFSET : GPCR_OFFSET));
gpdr = pxa->regbase + GPDR_OFFSET;
local_irq_save(flags);
tmp = __raw_readl(gpdr);
tmp |= mask;
__raw_writel(tmp, gpdr);
local_irq_restore(flags);
return 0;
}
/*
* Return GPIO level
*/
static int pxa_gpio_get(struct gpio_chip *chip, unsigned offset)
{
u32 mask = 1 << offset;
struct pxa_gpio_chip *pxa;
pxa = container_of(chip, struct pxa_gpio_chip, chip);
return __raw_readl(pxa->regbase + GPLR_OFFSET) & mask;
}
/*
* Set output GPIO level
*/
static void pxa_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
u32 mask = 1 << offset;
struct pxa_gpio_chip *pxa;
pxa = container_of(chip, struct pxa_gpio_chip, chip);
if (value)
__raw_writel(mask, pxa->regbase + GPSR_OFFSET);
else
__raw_writel(mask, pxa->regbase + GPCR_OFFSET);
}
#define GPIO_CHIP(_n) \
[_n] = { \
.regbase = GPIO##_n##_BASE, \
.chip = { \
.label = "gpio-" #_n, \
.direction_input = pxa_gpio_direction_input, \
.direction_output = pxa_gpio_direction_output, \
.get = pxa_gpio_get, \
.set = pxa_gpio_set, \
.base = (_n) * 32, \
.ngpio = 32, \
}, \
}
static struct pxa_gpio_chip pxa_gpio_chip[] = {
GPIO_CHIP(0),
GPIO_CHIP(1),
GPIO_CHIP(2),
#if defined(CONFIG_PXA27x) || defined(CONFIG_PXA3xx)
GPIO_CHIP(3),
#endif
};
/*
* PXA GPIO edge detection for IRQs:
* IRQs are generated on Falling-Edge, Rising-Edge, or both.
* Use this instead of directly setting GRER/GFER.
*/
static unsigned long GPIO_IRQ_rising_edge[4];
static unsigned long GPIO_IRQ_falling_edge[4];
static unsigned long GPIO_IRQ_mask[4];
/*
* On PXA25x and PXA27x, GAFRx and GPDRx together decide the alternate
* function of a GPIO, and GPDRx cannot be altered once configured. It
* is attributed as "occupied" here (I know this terminology isn't
* accurate, you are welcome to propose a better one :-)
*/
static int __gpio_is_occupied(unsigned gpio)
{
if (cpu_is_pxa25x() || cpu_is_pxa27x())
return GAFR(gpio) & (0x3 << (((gpio) & 0xf) * 2));
else
return 0;
}
static int pxa_gpio_irq_type(unsigned int irq, unsigned int type)
{
int gpio, idx;
gpio = IRQ_TO_GPIO(irq);
idx = gpio >> 5;
if (type == IRQ_TYPE_PROBE) {
/* Don't mess with enabled GPIOs using preconfigured edges or
* GPIOs set to alternate function or to output during probe
*/
if ((GPIO_IRQ_rising_edge[idx] |
GPIO_IRQ_falling_edge[idx] |
GPDR(gpio)) & GPIO_bit(gpio))
return 0;
if (__gpio_is_occupied(gpio))
return 0;
type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
}
GPDR(gpio) &= ~GPIO_bit(gpio);
if (type & IRQ_TYPE_EDGE_RISING)
__set_bit(gpio, GPIO_IRQ_rising_edge);
else
__clear_bit(gpio, GPIO_IRQ_rising_edge);
if (type & IRQ_TYPE_EDGE_FALLING)
__set_bit(gpio, GPIO_IRQ_falling_edge);
else
__clear_bit(gpio, GPIO_IRQ_falling_edge);
GRER(gpio) = GPIO_IRQ_rising_edge[idx] & GPIO_IRQ_mask[idx];
GFER(gpio) = GPIO_IRQ_falling_edge[idx] & GPIO_IRQ_mask[idx];
pr_debug("%s: IRQ%d (GPIO%d) - edge%s%s\n", __func__, irq, gpio,
((type & IRQ_TYPE_EDGE_RISING) ? " rising" : ""),
((type & IRQ_TYPE_EDGE_FALLING) ? " falling" : ""));
return 0;
}
/*
* GPIO IRQs must be acknowledged. This is for GPIO 0 and 1.
*/
static void pxa_ack_low_gpio(unsigned int irq)
{
GEDR0 = (1 << (irq - IRQ_GPIO0));
}
static void pxa_mask_low_gpio(unsigned int irq)
{
ICMR &= ~(1 << (irq - PXA_IRQ(0)));
}
static void pxa_unmask_low_gpio(unsigned int irq)
{
ICMR |= 1 << (irq - PXA_IRQ(0));
}
static struct irq_chip pxa_low_gpio_chip = {
.name = "GPIO-l",
.ack = pxa_ack_low_gpio,
.mask = pxa_mask_low_gpio,
.unmask = pxa_unmask_low_gpio,
.set_type = pxa_gpio_irq_type,
};
/*
* Demux handler for GPIO>=2 edge detect interrupts
*/
#define GEDR_BITS (sizeof(gedr) * BITS_PER_BYTE)
static void pxa_gpio_demux_handler(unsigned int irq, struct irq_desc *desc)
{
int loop, bit, n;
unsigned long gedr[4];
do {
gedr[0] = GEDR0 & GPIO_IRQ_mask[0] & ~3;
gedr[1] = GEDR1 & GPIO_IRQ_mask[1];
gedr[2] = GEDR2 & GPIO_IRQ_mask[2];
gedr[3] = GEDR3 & GPIO_IRQ_mask[3];
GEDR0 = gedr[0]; GEDR1 = gedr[1];
GEDR2 = gedr[2]; GEDR3 = gedr[3];
loop = 0;
bit = find_first_bit(gedr, GEDR_BITS);
while (bit < GEDR_BITS) {
loop = 1;
n = PXA_GPIO_IRQ_BASE + bit;
generic_handle_irq(n);
bit = find_next_bit(gedr, GEDR_BITS, bit + 1);
}
} while (loop);
}
static void pxa_ack_muxed_gpio(unsigned int irq)
{
int gpio = irq - IRQ_GPIO(2) + 2;
GEDR(gpio) = GPIO_bit(gpio);
}
static void pxa_mask_muxed_gpio(unsigned int irq)
{
int gpio = irq - IRQ_GPIO(2) + 2;
__clear_bit(gpio, GPIO_IRQ_mask);
GRER(gpio) &= ~GPIO_bit(gpio);
GFER(gpio) &= ~GPIO_bit(gpio);
}
static void pxa_unmask_muxed_gpio(unsigned int irq)
{
int gpio = irq - IRQ_GPIO(2) + 2;
int idx = gpio >> 5;
__set_bit(gpio, GPIO_IRQ_mask);
GRER(gpio) = GPIO_IRQ_rising_edge[idx] & GPIO_IRQ_mask[idx];
GFER(gpio) = GPIO_IRQ_falling_edge[idx] & GPIO_IRQ_mask[idx];
}
static struct irq_chip pxa_muxed_gpio_chip = {
.name = "GPIO",
.ack = pxa_ack_muxed_gpio,
.mask = pxa_mask_muxed_gpio,
.unmask = pxa_unmask_muxed_gpio,
.set_type = pxa_gpio_irq_type,
};
void __init pxa_init_gpio(int gpio_nr, set_wake_t fn)
{
int irq, i, gpio;
pxa_last_gpio = gpio_nr - 1;
/* clear all GPIO edge detects */
for (i = 0; i < gpio_nr; i += 32) {
GFER(i) = 0;
GRER(i) = 0;
GEDR(i) = GEDR(i);
}
/* GPIO 0 and 1 must have their mask bit always set */
GPIO_IRQ_mask[0] = 3;
for (irq = IRQ_GPIO0; irq <= IRQ_GPIO1; irq++) {
set_irq_chip(irq, &pxa_low_gpio_chip);
set_irq_handler(irq, handle_edge_irq);
set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
}
for (irq = IRQ_GPIO(2); irq < IRQ_GPIO(gpio_nr); irq++) {
set_irq_chip(irq, &pxa_muxed_gpio_chip);
set_irq_handler(irq, handle_edge_irq);
set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
}
/* Install handler for GPIO>=2 edge detect interrupts */
set_irq_chained_handler(IRQ_GPIO_2_x, pxa_gpio_demux_handler);
pxa_low_gpio_chip.set_wake = fn;
pxa_muxed_gpio_chip.set_wake = fn;
/* add a GPIO chip for each register bank.
* the last PXA25x register only contains 21 GPIOs
*/
for (gpio = 0, i = 0; gpio < gpio_nr; gpio += 32, i++) {
if (gpio + 32 > gpio_nr)
pxa_gpio_chip[i].chip.ngpio = gpio_nr - gpio;
gpiochip_add(&pxa_gpio_chip[i].chip);
}
}
#ifdef CONFIG_PM
static unsigned long saved_gplr[4];
static unsigned long saved_gpdr[4];
static unsigned long saved_grer[4];
static unsigned long saved_gfer[4];
static int pxa_gpio_suspend(struct sys_device *dev, pm_message_t state)
{
int i, gpio;
for (gpio = 0, i = 0; gpio < pxa_last_gpio; gpio += 32, i++) {
saved_gplr[i] = GPLR(gpio);
saved_gpdr[i] = GPDR(gpio);
saved_grer[i] = GRER(gpio);
saved_gfer[i] = GFER(gpio);
/* Clear GPIO transition detect bits */
GEDR(gpio) = GEDR(gpio);
}
return 0;
}
static int pxa_gpio_resume(struct sys_device *dev)
{
int i, gpio;
for (gpio = 0, i = 0; gpio < pxa_last_gpio; gpio += 32, i++) {
/* restore level with set/clear */
GPSR(gpio) = saved_gplr[i];
GPCR(gpio) = ~saved_gplr[i];
GRER(gpio) = saved_grer[i];
GFER(gpio) = saved_gfer[i];
GPDR(gpio) = saved_gpdr[i];
}
return 0;
}
#else
#define pxa_gpio_suspend NULL
#define pxa_gpio_resume NULL
#endif
struct sysdev_class pxa_gpio_sysclass = {
.name = "gpio",
.suspend = pxa_gpio_suspend,
.resume = pxa_gpio_resume,
};
static int __init pxa_gpio_init(void)
{
return sysdev_class_register(&pxa_gpio_sysclass);
}
core_initcall(pxa_gpio_init);