- 根目录:
- drivers
- gpio
- gpio-pxa.c
/*
* linux/arch/arm/plat-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/clk.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/gpio-pxa.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/syscore_ops.h>
#include <linux/slab.h>
/*
* We handle the GPIOs by banks, each bank covers up to 32 GPIOs with
* one set of registers. The register offsets are organized below:
*
* GPLR GPDR GPSR GPCR GRER GFER GEDR
* BANK 0 - 0x0000 0x000C 0x0018 0x0024 0x0030 0x003C 0x0048
* BANK 1 - 0x0004 0x0010 0x001C 0x0028 0x0034 0x0040 0x004C
* BANK 2 - 0x0008 0x0014 0x0020 0x002C 0x0038 0x0044 0x0050
*
* BANK 3 - 0x0100 0x010C 0x0118 0x0124 0x0130 0x013C 0x0148
* BANK 4 - 0x0104 0x0110 0x011C 0x0128 0x0134 0x0140 0x014C
* BANK 5 - 0x0108 0x0114 0x0120 0x012C 0x0138 0x0144 0x0150
*
* NOTE:
* BANK 3 is only available on PXA27x and later processors.
* BANK 4 and 5 are only available on PXA935
*/
#define GPLR_OFFSET 0x00
#define GPDR_OFFSET 0x0C
#define GPSR_OFFSET 0x18
#define GPCR_OFFSET 0x24
#define GRER_OFFSET 0x30
#define GFER_OFFSET 0x3C
#define GEDR_OFFSET 0x48
#define GAFR_OFFSET 0x54
#define ED_MASK_OFFSET 0x9C /* GPIO edge detection for AP side */
#define BANK_OFF(n) (((n) < 3) ? (n) << 2 : 0x100 + (((n) - 3) << 2))
int pxa_last_gpio;
struct pxa_gpio_chip {
struct gpio_chip chip;
void __iomem *regbase;
char label[10];
unsigned long irq_mask;
unsigned long irq_edge_rise;
unsigned long irq_edge_fall;
#ifdef CONFIG_PM
unsigned long saved_gplr;
unsigned long saved_gpdr;
unsigned long saved_grer;
unsigned long saved_gfer;
#endif
};
enum {
PXA25X_GPIO = 0,
PXA26X_GPIO,
PXA27X_GPIO,
PXA3XX_GPIO,
PXA93X_GPIO,
MMP_GPIO = 0x10,
MMP2_GPIO,
};
static DEFINE_SPINLOCK(gpio_lock);
static struct pxa_gpio_chip *pxa_gpio_chips;
static int gpio_type;
static void __iomem *gpio_reg_base;
#define for_each_gpio_chip(i, c) \
for (i = 0, c = &pxa_gpio_chips[0]; i <= pxa_last_gpio; i += 32, c++)
static inline void __iomem *gpio_chip_base(struct gpio_chip *c)
{
return container_of(c, struct pxa_gpio_chip, chip)->regbase;
}
static inline struct pxa_gpio_chip *gpio_to_pxachip(unsigned gpio)
{
return &pxa_gpio_chips[gpio_to_bank(gpio)];
}
static inline int gpio_is_pxa_type(int type)
{
return (type & MMP_GPIO) == 0;
}
static inline int gpio_is_mmp_type(int type)
{
return (type & MMP_GPIO) != 0;
}
/* GPIO86/87/88/89 on PXA26x have their direction bits in PXA_GPDR(2 inverted,
* as well as their Alternate Function value being '1' for GPIO in GAFRx.
*/
static inline int __gpio_is_inverted(int gpio)
{
if ((gpio_type == PXA26X_GPIO) && (gpio > 85))
return 1;
return 0;
}
/*
* 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 inline int __gpio_is_occupied(unsigned gpio)
{
struct pxa_gpio_chip *pxachip;
void __iomem *base;
unsigned long gafr = 0, gpdr = 0;
int ret, af = 0, dir = 0;
pxachip = gpio_to_pxachip(gpio);
base = gpio_chip_base(&pxachip->chip);
gpdr = readl_relaxed(base + GPDR_OFFSET);
switch (gpio_type) {
case PXA25X_GPIO:
case PXA26X_GPIO:
case PXA27X_GPIO:
gafr = readl_relaxed(base + GAFR_OFFSET);
af = (gafr >> ((gpio & 0xf) * 2)) & 0x3;
dir = gpdr & GPIO_bit(gpio);
if (__gpio_is_inverted(gpio))
ret = (af != 1) || (dir == 0);
else
ret = (af != 0) || (dir != 0);
break;
default:
ret = gpdr & GPIO_bit(gpio);
break;
}
return ret;
}
#ifdef CONFIG_ARCH_PXA
static inline int __pxa_gpio_to_irq(int gpio)
{
if (gpio_is_pxa_type(gpio_type))
return PXA_GPIO_TO_IRQ(gpio);
return -1;
}
static inline int __pxa_irq_to_gpio(int irq)
{
if (gpio_is_pxa_type(gpio_type))
return irq - PXA_GPIO_TO_IRQ(0);
return -1;
}
#else
static inline int __pxa_gpio_to_irq(int gpio) { return -1; }
static inline int __pxa_irq_to_gpio(int irq) { return -1; }
#endif
#ifdef CONFIG_ARCH_MMP
static inline int __mmp_gpio_to_irq(int gpio)
{
if (gpio_is_mmp_type(gpio_type))
return MMP_GPIO_TO_IRQ(gpio);
return -1;
}
static inline int __mmp_irq_to_gpio(int irq)
{
if (gpio_is_mmp_type(gpio_type))
return irq - MMP_GPIO_TO_IRQ(0);
return -1;
}
#else
static inline int __mmp_gpio_to_irq(int gpio) { return -1; }
static inline int __mmp_irq_to_gpio(int irq) { return -1; }
#endif
static int pxa_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
int gpio, ret;
gpio = chip->base + offset;
ret = __pxa_gpio_to_irq(gpio);
if (ret >= 0)
return ret;
return __mmp_gpio_to_irq(gpio);
}
int pxa_irq_to_gpio(int irq)
{
int ret;
ret = __pxa_irq_to_gpio(irq);
if (ret >= 0)
return ret;
return __mmp_irq_to_gpio(irq);
}
static int pxa_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
void __iomem *base = gpio_chip_base(chip);
uint32_t value, mask = 1 << offset;
unsigned long flags;
spin_lock_irqsave(&gpio_lock, flags);
value = readl_relaxed(base + GPDR_OFFSET);
if (__gpio_is_inverted(chip->base + offset))
value |= mask;
else
value &= ~mask;
writel_relaxed(value, base + GPDR_OFFSET);
spin_unlock_irqrestore(&gpio_lock, flags);
return 0;
}
static int pxa_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int value)
{
void __iomem *base = gpio_chip_base(chip);
uint32_t tmp, mask = 1 << offset;
unsigned long flags;
writel_relaxed(mask, base + (value ? GPSR_OFFSET : GPCR_OFFSET));
spin_lock_irqsave(&gpio_lock, flags);
tmp = readl_relaxed(base + GPDR_OFFSET);
if (__gpio_is_inverted(chip->base + offset))
tmp &= ~mask;
else
tmp |= mask;
writel_relaxed(tmp, base + GPDR_OFFSET);
spin_unlock_irqrestore(&gpio_lock, flags);
return 0;
}
static int pxa_gpio_get(struct gpio_chip *chip, unsigned offset)
{
return readl_relaxed(gpio_chip_base(chip) + GPLR_OFFSET) & (1 << offset);
}
static void pxa_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
writel_relaxed(1 << offset, gpio_chip_base(chip) +
(value ? GPSR_OFFSET : GPCR_OFFSET));
}
static int __devinit pxa_init_gpio_chip(int gpio_end)
{
int i, gpio, nbanks = gpio_to_bank(gpio_end) + 1;
struct pxa_gpio_chip *chips;
chips = kzalloc(nbanks * sizeof(struct pxa_gpio_chip), GFP_KERNEL);
if (chips == NULL) {
pr_err("%s: failed to allocate GPIO chips\n", __func__);
return -ENOMEM;
}
for (i = 0, gpio = 0; i < nbanks; i++, gpio += 32) {
struct gpio_chip *c = &chips[i].chip;
sprintf(chips[i].label, "gpio-%d", i);
chips[i].regbase = gpio_reg_base + BANK_OFF(i);
c->base = gpio;
c->label = chips[i].label;
c->direction_input = pxa_gpio_direction_input;
c->direction_output = pxa_gpio_direction_output;
c->get = pxa_gpio_get;
c->set = pxa_gpio_set;
c->to_irq = pxa_gpio_to_irq;
/* number of GPIOs on last bank may be less than 32 */
c->ngpio = (gpio + 31 > gpio_end) ? (gpio_end - gpio + 1) : 32;
gpiochip_add(c);
}
pxa_gpio_chips = chips;
return 0;
}
/* Update only those GRERx and GFERx edge detection register bits if those
* bits are set in c->irq_mask
*/
static inline void update_edge_detect(struct pxa_gpio_chip *c)
{
uint32_t grer, gfer;
grer = readl_relaxed(c->regbase + GRER_OFFSET) & ~c->irq_mask;
gfer = readl_relaxed(c->regbase + GFER_OFFSET) & ~c->irq_mask;
grer |= c->irq_edge_rise & c->irq_mask;
gfer |= c->irq_edge_fall & c->irq_mask;
writel_relaxed(grer, c->regbase + GRER_OFFSET);
writel_relaxed(gfer, c->regbase + GFER_OFFSET);
}
static int pxa_gpio_irq_type(struct irq_data *d, unsigned int type)
{
struct pxa_gpio_chip *c;
int gpio = pxa_irq_to_gpio(d->irq);
unsigned long gpdr, mask = GPIO_bit(gpio);
c = gpio_to_pxachip(gpio);
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 ((c->irq_edge_rise | c->irq_edge_fall) & GPIO_bit(gpio))
return 0;
if (__gpio_is_occupied(gpio))
return 0;
type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
}
gpdr = readl_relaxed(c->regbase + GPDR_OFFSET);
if (__gpio_is_inverted(gpio))
writel_relaxed(gpdr | mask, c->regbase + GPDR_OFFSET);
else
writel_relaxed(gpdr & ~mask, c->regbase + GPDR_OFFSET);
if (type & IRQ_TYPE_EDGE_RISING)
c->irq_edge_rise |= mask;
else
c->irq_edge_rise &= ~mask;
if (type & IRQ_TYPE_EDGE_FALLING)
c->irq_edge_fall |= mask;
else
c->irq_edge_fall &= ~mask;
update_edge_detect(c);
pr_debug("%s: IRQ%d (GPIO%d) - edge%s%s\n", __func__, d->irq, gpio,
((type & IRQ_TYPE_EDGE_RISING) ? " rising" : ""),
((type & IRQ_TYPE_EDGE_FALLING) ? " falling" : ""));
return 0;
}
static void pxa_gpio_demux_handler(unsigned int irq, struct irq_desc *desc)
{
struct pxa_gpio_chip *c;
int loop, gpio, gpio_base, n;
unsigned long gedr;
do {
loop = 0;
for_each_gpio_chip(gpio, c) {
gpio_base = c->chip.base;
gedr = readl_relaxed(c->regbase + GEDR_OFFSET);
gedr = gedr & c->irq_mask;
writel_relaxed(gedr, c->regbase + GEDR_OFFSET);
n = find_first_bit(&gedr, BITS_PER_LONG);
while (n < BITS_PER_LONG) {
loop = 1;
generic_handle_irq(gpio_to_irq(gpio_base + n));
n = find_next_bit(&gedr, BITS_PER_LONG, n + 1);
}
}
} while (loop);
}
static void pxa_ack_muxed_gpio(struct irq_data *d)
{
int gpio = pxa_irq_to_gpio(d->irq);
struct pxa_gpio_chip *c = gpio_to_pxachip(gpio);
writel_relaxed(GPIO_bit(gpio), c->regbase + GEDR_OFFSET);
}
static void pxa_mask_muxed_gpio(struct irq_data *d)
{
int gpio = pxa_irq_to_gpio(d->irq);
struct pxa_gpio_chip *c = gpio_to_pxachip(gpio);
uint32_t grer, gfer;
c->irq_mask &= ~GPIO_bit(gpio);
grer = readl_relaxed(c->regbase + GRER_OFFSET) & ~GPIO_bit(gpio);
gfer = readl_relaxed(c->regbase + GFER_OFFSET) & ~GPIO_bit(gpio);
writel_relaxed(grer, c->regbase + GRER_OFFSET);
writel_relaxed(gfer, c->regbase + GFER_OFFSET);
}
static void pxa_unmask_muxed_gpio(struct irq_data *d)
{
int gpio = pxa_irq_to_gpio(d->irq);
struct pxa_gpio_chip *c = gpio_to_pxachip(gpio);
c->irq_mask |= GPIO_bit(gpio);
update_edge_detect(c);
}
static struct irq_chip pxa_muxed_gpio_chip = {
.name = "GPIO",
.irq_ack = pxa_ack_muxed_gpio,
.irq_mask = pxa_mask_muxed_gpio,
.irq_unmask = pxa_unmask_muxed_gpio,
.irq_set_type = pxa_gpio_irq_type,
};
static int pxa_gpio_nums(void)
{
int count = 0;
#ifdef CONFIG_ARCH_PXA
if (cpu_is_pxa25x()) {
#ifdef CONFIG_CPU_PXA26x
count = 89;
gpio_type = PXA26X_GPIO;
#elif defined(CONFIG_PXA25x)
count = 84;
gpio_type = PXA26X_GPIO;
#endif /* CONFIG_CPU_PXA26x */
} else if (cpu_is_pxa27x()) {
count = 120;
gpio_type = PXA27X_GPIO;
} else if (cpu_is_pxa93x() || cpu_is_pxa95x()) {
count = 191;
gpio_type = PXA93X_GPIO;
} else if (cpu_is_pxa3xx()) {
count = 127;
gpio_type = PXA3XX_GPIO;
}
#endif /* CONFIG_ARCH_PXA */
#ifdef CONFIG_ARCH_MMP
if (cpu_is_pxa168() || cpu_is_pxa910()) {
count = 127;
gpio_type = MMP_GPIO;
} else if (cpu_is_mmp2()) {
count = 191;
gpio_type = MMP2_GPIO;
}
#endif /* CONFIG_ARCH_MMP */
return count;
}
static int __devinit pxa_gpio_probe(struct platform_device *pdev)
{
struct pxa_gpio_chip *c;
struct resource *res;
struct clk *clk;
int gpio, irq, ret;
int irq0 = 0, irq1 = 0, irq_mux, gpio_offset = 0;
pxa_last_gpio = pxa_gpio_nums();
if (!pxa_last_gpio)
return -EINVAL;
irq0 = platform_get_irq_byname(pdev, "gpio0");
irq1 = platform_get_irq_byname(pdev, "gpio1");
irq_mux = platform_get_irq_byname(pdev, "gpio_mux");
if ((irq0 > 0 && irq1 <= 0) || (irq0 <= 0 && irq1 > 0)
|| (irq_mux <= 0))
return -EINVAL;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -EINVAL;
gpio_reg_base = ioremap(res->start, resource_size(res));
if (!gpio_reg_base)
return -EINVAL;
if (irq0 > 0)
gpio_offset = 2;
clk = clk_get(&pdev->dev, NULL);
if (IS_ERR(clk)) {
dev_err(&pdev->dev, "Error %ld to get gpio clock\n",
PTR_ERR(clk));
iounmap(gpio_reg_base);
return PTR_ERR(clk);
}
ret = clk_prepare(clk);
if (ret) {
clk_put(clk);
iounmap(gpio_reg_base);
return ret;
}
ret = clk_enable(clk);
if (ret) {
clk_unprepare(clk);
clk_put(clk);
iounmap(gpio_reg_base);
return ret;
}
/* Initialize GPIO chips */
pxa_init_gpio_chip(pxa_last_gpio);
/* clear all GPIO edge detects */
for_each_gpio_chip(gpio, c) {
writel_relaxed(0, c->regbase + GFER_OFFSET);
writel_relaxed(0, c->regbase + GRER_OFFSET);
writel_relaxed(~0,c->regbase + GEDR_OFFSET);
/* unmask GPIO edge detect for AP side */
if (gpio_is_mmp_type(gpio_type))
writel_relaxed(~0, c->regbase + ED_MASK_OFFSET);
}
#ifdef CONFIG_ARCH_PXA
irq = gpio_to_irq(0);
irq_set_chip_and_handler(irq, &pxa_muxed_gpio_chip,
handle_edge_irq);
set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
irq_set_chained_handler(IRQ_GPIO0, pxa_gpio_demux_handler);
irq = gpio_to_irq(1);
irq_set_chip_and_handler(irq, &pxa_muxed_gpio_chip,
handle_edge_irq);
set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
irq_set_chained_handler(IRQ_GPIO1, pxa_gpio_demux_handler);
#endif
for (irq = gpio_to_irq(gpio_offset);
irq <= gpio_to_irq(pxa_last_gpio); irq++) {
irq_set_chip_and_handler(irq, &pxa_muxed_gpio_chip,
handle_edge_irq);
set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
}
irq_set_chained_handler(irq_mux, pxa_gpio_demux_handler);
return 0;
}
static struct platform_driver pxa_gpio_driver = {
.probe = pxa_gpio_probe,
.driver = {
.name = "pxa-gpio",
},
};
static int __init pxa_gpio_init(void)
{
return platform_driver_register(&pxa_gpio_driver);
}
postcore_initcall(pxa_gpio_init);
#ifdef CONFIG_PM
static int pxa_gpio_suspend(void)
{
struct pxa_gpio_chip *c;
int gpio;
for_each_gpio_chip(gpio, c) {
c->saved_gplr = readl_relaxed(c->regbase + GPLR_OFFSET);
c->saved_gpdr = readl_relaxed(c->regbase + GPDR_OFFSET);
c->saved_grer = readl_relaxed(c->regbase + GRER_OFFSET);
c->saved_gfer = readl_relaxed(c->regbase + GFER_OFFSET);
/* Clear GPIO transition detect bits */
writel_relaxed(0xffffffff, c->regbase + GEDR_OFFSET);
}
return 0;
}
static void pxa_gpio_resume(void)
{
struct pxa_gpio_chip *c;
int gpio;
for_each_gpio_chip(gpio, c) {
/* restore level with set/clear */
writel_relaxed( c->saved_gplr, c->regbase + GPSR_OFFSET);
writel_relaxed(~c->saved_gplr, c->regbase + GPCR_OFFSET);
writel_relaxed(c->saved_grer, c->regbase + GRER_OFFSET);
writel_relaxed(c->saved_gfer, c->regbase + GFER_OFFSET);
writel_relaxed(c->saved_gpdr, c->regbase + GPDR_OFFSET);
}
}
#else
#define pxa_gpio_suspend NULL
#define pxa_gpio_resume NULL
#endif
struct syscore_ops pxa_gpio_syscore_ops = {
.suspend = pxa_gpio_suspend,
.resume = pxa_gpio_resume,
};
static int __init pxa_gpio_sysinit(void)
{
register_syscore_ops(&pxa_gpio_syscore_ops);
return 0;
}
postcore_initcall(pxa_gpio_sysinit);