Openwrt/target/linux/xburst/files-2.6.32/arch/mips/jz4740/gpio.c
Lars-Peter Clausen c0b9c9d4a9 jz4740-gpio: Fix potential race condition
SVN-Revision: 20071
2010-03-08 20:34:40 +00:00

541 lines
14 KiB
C

/*
* Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
* JZ4740 platform GPIO support
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/sysdev.h>
#include <linux/io.h>
#include <linux/gpio.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/bitops.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#define JZ_GPIO_BASE_A (32*0)
#define JZ_GPIO_BASE_B (32*1)
#define JZ_GPIO_BASE_C (32*2)
#define JZ_GPIO_BASE_D (32*3)
#define JZ_GPIO_NUM_A 32
#define JZ_GPIO_NUM_B 32
#define JZ_GPIO_NUM_C 31
#define JZ_GPIO_NUM_D 32
#define JZ_IRQ_GPIO_BASE_A (JZ_IRQ_GPIO(0) + JZ_GPIO_BASE_A)
#define JZ_IRQ_GPIO_BASE_B (JZ_IRQ_GPIO(0) + JZ_GPIO_BASE_B)
#define JZ_IRQ_GPIO_BASE_C (JZ_IRQ_GPIO(0) + JZ_GPIO_BASE_C)
#define JZ_IRQ_GPIO_BASE_D (JZ_IRQ_GPIO(0) + JZ_GPIO_BASE_D)
#define JZ_IRQ_GPIO_A(num) (JZ_IRQ_GPIO_BASE_A + num)
#define JZ_IRQ_GPIO_B(num) (JZ_IRQ_GPIO_BASE_B + num)
#define JZ_IRQ_GPIO_C(num) (JZ_IRQ_GPIO_BASE_C + num)
#define JZ_IRQ_GPIO_D(num) (JZ_IRQ_GPIO_BASE_D + num)
#define JZ_REG_GPIO_PIN 0x00
#define JZ_REG_GPIO_DATA 0x10
#define JZ_REG_GPIO_DATA_SET 0x14
#define JZ_REG_GPIO_DATA_CLEAR 0x18
#define JZ_REG_GPIO_MASK 0x20
#define JZ_REG_GPIO_MASK_SET 0x24
#define JZ_REG_GPIO_MASK_CLEAR 0x28
#define JZ_REG_GPIO_PULL 0x30
#define JZ_REG_GPIO_PULL_SET 0x34
#define JZ_REG_GPIO_PULL_CLEAR 0x38
#define JZ_REG_GPIO_FUNC 0x40
#define JZ_REG_GPIO_FUNC_SET 0x44
#define JZ_REG_GPIO_FUNC_CLEAR 0x48
#define JZ_REG_GPIO_SELECT 0x50
#define JZ_REG_GPIO_SELECT_SET 0x54
#define JZ_REG_GPIO_SELECT_CLEAR 0x58
#define JZ_REG_GPIO_DIRECTION 0x60
#define JZ_REG_GPIO_DIRECTION_SET 0x64
#define JZ_REG_GPIO_DIRECTION_CLEAR 0x68
#define JZ_REG_GPIO_TRIGGER 0x70
#define JZ_REG_GPIO_TRIGGER_SET 0x74
#define JZ_REG_GPIO_TRIGGER_CLEAR 0x78
#define JZ_REG_GPIO_FLAG 0x80
#define JZ_REG_GPIO_FLAG_CLEAR 0x14
#define CHIP_TO_REG(chip, reg) (jz_gpio_base + (((chip)->base) << 3) + reg)
#define GPIO_TO_BIT(gpio) BIT(gpio & 0x1f)
#define GPIO_TO_REG(gpio, reg) (jz_gpio_base + ((gpio >> 5) << 8) + reg)
static void __iomem *jz_gpio_base;
struct jz_gpio_chip {
unsigned int irq;
unsigned int irq_base;
uint32_t wakeup;
uint32_t suspend_mask;
uint32_t edge_trigger_both;
spinlock_t lock;
struct gpio_chip gpio_chip;
struct irq_chip irq_chip;
};
static struct jz_gpio_chip *jz_irq_to_chip(unsigned int irq)
{
return get_irq_chip_data(irq);
}
static inline void jz_gpio_write_bit(unsigned int gpio, unsigned int reg)
{
writel(GPIO_TO_BIT(gpio), GPIO_TO_REG(gpio, reg));
}
int jz_gpio_set_function(int gpio, enum jz_gpio_function function)
{
if (function == JZ_GPIO_FUNC_NONE) {
jz_gpio_write_bit(gpio, JZ_REG_GPIO_FUNC_CLEAR);
jz_gpio_write_bit(gpio, JZ_REG_GPIO_SELECT_CLEAR);
jz_gpio_write_bit(gpio, JZ_REG_GPIO_TRIGGER_CLEAR);
} else {
jz_gpio_write_bit(gpio, JZ_REG_GPIO_FUNC_SET);
jz_gpio_write_bit(gpio, JZ_REG_GPIO_TRIGGER_CLEAR);
switch (function) {
case JZ_GPIO_FUNC1:
jz_gpio_write_bit(gpio, JZ_REG_GPIO_SELECT_CLEAR);
break;
case JZ_GPIO_FUNC3:
jz_gpio_write_bit(gpio, JZ_REG_GPIO_TRIGGER_SET);
case JZ_GPIO_FUNC2: /* Falltrough */
jz_gpio_write_bit(gpio, JZ_REG_GPIO_SELECT_SET);
break;
default:
BUG();
break;
}
}
return 0;
}
EXPORT_SYMBOL_GPL(jz_gpio_set_function);
int jz_gpio_bulk_request(const struct jz_gpio_bulk_request *request, size_t num)
{
size_t i;
int ret;
for (i = 0; i < num; ++i, ++request) {
ret = gpio_request(request->gpio, request->name);
if (ret)
goto err;
jz_gpio_set_function(request->gpio, request->function);
}
return 0;
err:
for (--request; i > 0; --i, --request)
gpio_free(request->gpio);
return ret;
}
EXPORT_SYMBOL_GPL(jz_gpio_bulk_request);
void jz_gpio_bulk_free(const struct jz_gpio_bulk_request *request, size_t num)
{
size_t i;
for (i = 0; i < num; ++i, ++request) {
gpio_free(request->gpio);
jz_gpio_set_function(request->gpio, JZ_GPIO_FUNC_NONE);
}
}
EXPORT_SYMBOL_GPL(jz_gpio_bulk_free);
void jz_gpio_bulk_suspend(const struct jz_gpio_bulk_request *request, size_t num)
{
size_t i;
for (i = 0; i < num; ++i, ++request) {
jz_gpio_set_function(request->gpio, JZ_GPIO_FUNC_NONE);
jz_gpio_write_bit(request->gpio, JZ_REG_GPIO_DIRECTION_CLEAR);
jz_gpio_write_bit(request->gpio, JZ_REG_GPIO_PULL_SET);
}
}
EXPORT_SYMBOL_GPL(jz_gpio_bulk_suspend);
void jz_gpio_bulk_resume(const struct jz_gpio_bulk_request *request, size_t num)
{
size_t i;
for (i = 0; i < num; ++i, ++request) {
jz_gpio_set_function(request->gpio, request->function);
}
}
EXPORT_SYMBOL_GPL(jz_gpio_bulk_resume);
void jz_gpio_enable_pullup(unsigned gpio)
{
jz_gpio_write_bit(gpio, JZ_REG_GPIO_PULL_CLEAR);
}
EXPORT_SYMBOL_GPL(jz_gpio_enable_pullup);
void jz_gpio_disable_pullup(unsigned gpio)
{
jz_gpio_write_bit(gpio, JZ_REG_GPIO_PULL_SET);
}
EXPORT_SYMBOL_GPL(jz_gpio_disable_pullup);
static int jz_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
{
return !!(readl(CHIP_TO_REG(chip, JZ_REG_GPIO_PIN)) & BIT(gpio));
}
static void jz_gpio_set_value(struct gpio_chip *chip, unsigned gpio, int value)
{
uint32_t __iomem *reg = CHIP_TO_REG(chip, JZ_REG_GPIO_DATA_SET);
reg += !value;
writel(BIT(gpio), reg);
}
static int jz_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, int value)
{
writel(BIT(gpio), CHIP_TO_REG(chip, JZ_REG_GPIO_DIRECTION_SET));
jz_gpio_set_value(chip, gpio, value);
return 0;
}
static int jz_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
{
writel(BIT(gpio), CHIP_TO_REG(chip, JZ_REG_GPIO_DIRECTION_CLEAR));
return 0;
}
int jz_gpio_port_direction_input(int port, uint32_t mask)
{
writel(mask, GPIO_TO_REG(port, JZ_REG_GPIO_DIRECTION_CLEAR));
return 0;
}
EXPORT_SYMBOL(jz_gpio_port_direction_input);
int jz_gpio_port_direction_output(int port, uint32_t mask)
{
writel(mask, GPIO_TO_REG(port, JZ_REG_GPIO_DIRECTION_SET));
return 0;
}
EXPORT_SYMBOL(jz_gpio_port_direction_output);
void jz_gpio_port_set_value(int port, uint32_t value, uint32_t mask)
{
writel((~value) & mask, GPIO_TO_REG(port, JZ_REG_GPIO_DATA_CLEAR));
writel(value & mask, GPIO_TO_REG(port, JZ_REG_GPIO_DATA_SET));
}
EXPORT_SYMBOL(jz_gpio_port_set_value);
uint32_t jz_gpio_port_get_value(int port, uint32_t mask)
{
uint32_t value = readl(GPIO_TO_REG(port, JZ_REG_GPIO_PIN));
return value & mask;
}
EXPORT_SYMBOL(jz_gpio_port_get_value);
#define IRQ_TO_GPIO(irq) (irq - JZ_IRQ_GPIO(0))
#define IRQ_TO_BIT(irq) BIT(IRQ_TO_GPIO(irq) & 0x1f)
#define IRQ_TO_REG(irq, reg) GPIO_TO_REG(IRQ_TO_GPIO(irq), reg)
static void jz_gpio_irq_demux_handler(unsigned int irq, struct irq_desc *desc)
{
uint32_t flag;
unsigned int gpio_irq;
unsigned int gpio_bank;
struct jz_gpio_chip *chip = get_irq_desc_data(desc);
gpio_bank = JZ_IRQ_GPIO0 - irq;
flag = readl(jz_gpio_base + (gpio_bank << 8) + JZ_REG_GPIO_FLAG);
gpio_irq = ffs(flag) - 1;
if (chip->edge_trigger_both & BIT(gpio_irq)) {
uint32_t value = readl(CHIP_TO_REG(&chip->gpio_chip, JZ_REG_GPIO_PIN));
if (value & BIT(gpio_irq)) {
writel(BIT(gpio_irq),
CHIP_TO_REG(&chip->gpio_chip, JZ_REG_GPIO_DIRECTION_CLEAR));
} else {
writel(BIT(gpio_irq),
CHIP_TO_REG(&chip->gpio_chip, JZ_REG_GPIO_DIRECTION_SET));
}
}
gpio_irq += (gpio_bank << 5) + JZ_IRQ_GPIO(0);
generic_handle_irq(gpio_irq);
};
static inline void jz_gpio_set_irq_bit(unsigned int irq, unsigned int reg)
{
writel(IRQ_TO_BIT(irq), IRQ_TO_REG(irq, reg));
}
static void jz_gpio_irq_mask(unsigned int irq)
{
jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_MASK_SET);
};
static void jz_gpio_irq_unmask(unsigned int irq)
{
jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_MASK_CLEAR);
};
/* TODO: Check if function is gpio */
static unsigned int jz_gpio_irq_startup(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_SELECT_SET);
desc->status &= ~IRQ_MASKED;
jz_gpio_irq_unmask(irq);
return 0;
}
static void jz_gpio_irq_shutdown(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
jz_gpio_irq_mask(irq);
desc->status |= IRQ_MASKED;
/* Set direction to input */
jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_DIRECTION_CLEAR);
jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_SELECT_CLEAR);
}
static void jz_gpio_irq_ack(unsigned int irq)
{
jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_FLAG_CLEAR);
};
static int jz_gpio_irq_set_type(unsigned int irq, unsigned int flow_type)
{
struct jz_gpio_chip *chip = jz_irq_to_chip(irq);
struct irq_desc *desc = irq_to_desc(irq);
jz_gpio_irq_mask(irq);
if (flow_type == IRQ_TYPE_EDGE_BOTH) {
uint32_t value = readl(IRQ_TO_REG(irq, JZ_REG_GPIO_PIN));
if (value & IRQ_TO_BIT(irq))
flow_type = IRQ_TYPE_EDGE_FALLING;
else
flow_type = IRQ_TYPE_EDGE_RISING;
chip->edge_trigger_both |= IRQ_TO_BIT(irq);
} else {
chip->edge_trigger_both &= ~IRQ_TO_BIT(irq);
}
switch(flow_type) {
case IRQ_TYPE_EDGE_RISING:
jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_DIRECTION_SET);
jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_TRIGGER_SET);
break;
case IRQ_TYPE_EDGE_FALLING:
jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_DIRECTION_CLEAR);
jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_TRIGGER_SET);
break;
case IRQ_TYPE_LEVEL_HIGH:
jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_DIRECTION_SET);
jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_TRIGGER_CLEAR);
break;
case IRQ_TYPE_LEVEL_LOW:
jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_DIRECTION_CLEAR);
jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_TRIGGER_CLEAR);
break;
default:
return -EINVAL;
}
if (!(desc->status & IRQ_MASKED))
jz_gpio_irq_unmask(irq);
return 0;
}
static int jz_gpio_irq_set_wake(unsigned int irq, unsigned int on)
{
struct jz_gpio_chip *chip = jz_irq_to_chip(irq);
spin_lock(&chip->lock);
if (on)
chip->wakeup |= IRQ_TO_BIT(irq);
else
chip->wakeup &= ~IRQ_TO_BIT(irq);
spin_unlock(&chip->lock);
set_irq_wake(chip->irq, !!(chip->wakeup));
return 0;
}
int gpio_to_irq(unsigned gpio)
{
return JZ_IRQ_GPIO(0) + gpio;
}
EXPORT_SYMBOL_GPL(gpio_to_irq);
int irq_to_gpio(unsigned gpio)
{
return IRQ_TO_GPIO(gpio);
}
EXPORT_SYMBOL_GPL(irq_to_gpio);
#define JZ_GPIO_CHIP(_bank) { \
.irq_base = JZ_IRQ_GPIO_BASE_ ## _bank, \
.gpio_chip = { \
.label = "Bank " # _bank, \
.owner = THIS_MODULE, \
.set = jz_gpio_set_value, \
.get = jz_gpio_get_value, \
.direction_output = jz_gpio_direction_output, \
.direction_input = jz_gpio_direction_input, \
.base = JZ_GPIO_BASE_ ## _bank, \
.ngpio = JZ_GPIO_NUM_ ## _bank, \
}, \
.irq_chip = { \
.name = "GPIO Bank " # _bank, \
.mask = jz_gpio_irq_mask, \
.unmask = jz_gpio_irq_unmask, \
.ack = jz_gpio_irq_ack, \
.startup = jz_gpio_irq_startup, \
.shutdown = jz_gpio_irq_shutdown, \
.set_type = jz_gpio_irq_set_type, \
.set_wake = jz_gpio_irq_set_wake, \
}, \
}
static struct jz_gpio_chip jz_gpio_chips[] = {
JZ_GPIO_CHIP(A),
JZ_GPIO_CHIP(B),
JZ_GPIO_CHIP(C),
JZ_GPIO_CHIP(D),
};
int jz_gpio_suspend(void)
{
struct jz_gpio_chip *chip = jz_gpio_chips;
int i, gpio;
for (i = 0; i < ARRAY_SIZE(jz_gpio_chips); ++i, ++chip) {
gpio = chip->gpio_chip.base;
chip->suspend_mask = readl(GPIO_TO_REG(gpio, JZ_REG_GPIO_MASK));
writel(~(chip->wakeup), GPIO_TO_REG(gpio, JZ_REG_GPIO_MASK_SET));
writel(chip->wakeup, GPIO_TO_REG(gpio, JZ_REG_GPIO_MASK_CLEAR));
}
chip = jz_gpio_chips;
return 0;
}
int jz_gpio_resume(void)
{
struct jz_gpio_chip *chip = jz_gpio_chips;
int i;
for (i = 0; i < ARRAY_SIZE(jz_gpio_chips); ++i, ++chip) {
writel(~(chip->suspend_mask), GPIO_TO_REG(chip->gpio_chip.base,
JZ_REG_GPIO_MASK_CLEAR));
writel(chip->suspend_mask, GPIO_TO_REG(chip->gpio_chip.base,
JZ_REG_GPIO_MASK_SET));
}
return 0;
}
int __init jz_gpiolib_init(void)
{
struct jz_gpio_chip *chip = jz_gpio_chips;
int i, irq;
jz_gpio_base = ioremap(0x10010000, 0x400);
for (i = 0; i < ARRAY_SIZE(jz_gpio_chips); ++i, ++chip) {
gpiochip_add(&chip->gpio_chip);
spin_lock_init(&chip->lock);
chip->irq = JZ_IRQ_INTC_GPIO(i);
set_irq_data(chip->irq, chip);
set_irq_chained_handler(chip->irq, jz_gpio_irq_demux_handler);
for (irq = chip->irq_base; irq < chip->irq_base + chip->gpio_chip.ngpio; ++irq) {
set_irq_chip_and_handler(irq, &chip->irq_chip, handle_level_irq);
set_irq_chip_data(irq, chip);
}
}
printk("JZ GPIO initalized\n");
return 0;
}
#ifdef CONFIG_DEBUG_FS
static int gpio_regs_show(struct seq_file *s, void *unused)
{
struct jz_gpio_chip *chip = jz_gpio_chips;
int i;
for (i = 0; i < ARRAY_SIZE(jz_gpio_chips); ++i, ++chip) {
seq_printf(s, "GPIO %d: \n", i);
seq_printf(s, "\tPin: %.8x\n", readl(CHIP_TO_REG(&chip->gpio_chip, JZ_REG_GPIO_PIN)));
seq_printf(s, "\tData: %.8x\n", readl(CHIP_TO_REG(&chip->gpio_chip, JZ_REG_GPIO_DATA)));
seq_printf(s, "\tMask: %.8x\n", readl(CHIP_TO_REG(&chip->gpio_chip, JZ_REG_GPIO_MASK)));
seq_printf(s, "\tData: %.8x\n", readl(CHIP_TO_REG(&chip->gpio_chip, JZ_REG_GPIO_DATA)));
seq_printf(s, "\tPull: %.8x\n", readl(CHIP_TO_REG(&chip->gpio_chip, JZ_REG_GPIO_PULL)));
seq_printf(s, "\tFunc: %.8x\n", readl(CHIP_TO_REG(&chip->gpio_chip, JZ_REG_GPIO_FUNC)));
seq_printf(s, "\tSelect: %.8x\n", readl(CHIP_TO_REG(&chip->gpio_chip, JZ_REG_GPIO_SELECT)));
seq_printf(s, "\tDirection: %.8x\n", readl(CHIP_TO_REG(&chip->gpio_chip, JZ_REG_GPIO_DIRECTION)));
seq_printf(s, "\tTrigger: %.8x\n", readl(CHIP_TO_REG(&chip->gpio_chip, JZ_REG_GPIO_TRIGGER)));
seq_printf(s, "\tFlag: %.8x\n", readl(CHIP_TO_REG(&chip->gpio_chip, JZ_REG_GPIO_FLAG)));
}
return 0;
}
static int gpio_regs_open(struct inode *inode, struct file *file)
{
return single_open(file, gpio_regs_show, NULL);
}
static const struct file_operations gpio_regs_operations = {
.open = gpio_regs_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int __init gpio_debugfs_init(void)
{
(void) debugfs_create_file("jz_regs_gpio", S_IFREG | S_IRUGO,
NULL, NULL, &gpio_regs_operations);
return 0;
}
subsys_initcall(gpio_debugfs_init);
#endif