- 根目录:
- drivers
- gpio
- gpio-tegra.c
/*
* arch/arm/mach-tegra/gpio.c
*
* Copyright (c) 2010 Google, Inc
*
* Author:
* Erik Gilling <konkers@google.com>
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#include <linux/err.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/gpio.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/irqdomain.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pm.h>
#define GPIO_BANK(x) ((x) >> 5)
#define GPIO_PORT(x) (((x) >> 3) & 0x3)
#define GPIO_BIT(x) ((x) & 0x7)
#define GPIO_REG(x) (GPIO_BANK(x) * tegra_gpio_bank_stride + \
GPIO_PORT(x) * 4)
#define GPIO_CNF(x) (GPIO_REG(x) + 0x00)
#define GPIO_OE(x) (GPIO_REG(x) + 0x10)
#define GPIO_OUT(x) (GPIO_REG(x) + 0X20)
#define GPIO_IN(x) (GPIO_REG(x) + 0x30)
#define GPIO_INT_STA(x) (GPIO_REG(x) + 0x40)
#define GPIO_INT_ENB(x) (GPIO_REG(x) + 0x50)
#define GPIO_INT_LVL(x) (GPIO_REG(x) + 0x60)
#define GPIO_INT_CLR(x) (GPIO_REG(x) + 0x70)
#define GPIO_MSK_CNF(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x00)
#define GPIO_MSK_OE(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x10)
#define GPIO_MSK_OUT(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0X20)
#define GPIO_MSK_INT_STA(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x40)
#define GPIO_MSK_INT_ENB(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x50)
#define GPIO_MSK_INT_LVL(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x60)
#define GPIO_INT_LVL_MASK 0x010101
#define GPIO_INT_LVL_EDGE_RISING 0x000101
#define GPIO_INT_LVL_EDGE_FALLING 0x000100
#define GPIO_INT_LVL_EDGE_BOTH 0x010100
#define GPIO_INT_LVL_LEVEL_HIGH 0x000001
#define GPIO_INT_LVL_LEVEL_LOW 0x000000
struct tegra_gpio_bank {
int bank;
int irq;
spinlock_t lvl_lock[4];
#ifdef CONFIG_PM_SLEEP
u32 cnf[4];
u32 out[4];
u32 oe[4];
u32 int_enb[4];
u32 int_lvl[4];
u32 wake_enb[4];
#endif
};
static struct device *dev;
static struct irq_domain *irq_domain;
static void __iomem *regs;
static u32 tegra_gpio_bank_count;
static u32 tegra_gpio_bank_stride;
static u32 tegra_gpio_upper_offset;
static struct tegra_gpio_bank *tegra_gpio_banks;
static inline void tegra_gpio_writel(u32 val, u32 reg)
{
__raw_writel(val, regs + reg);
}
static inline u32 tegra_gpio_readl(u32 reg)
{
return __raw_readl(regs + reg);
}
static int tegra_gpio_compose(int bank, int port, int bit)
{
return (bank << 5) | ((port & 0x3) << 3) | (bit & 0x7);
}
static void tegra_gpio_mask_write(u32 reg, int gpio, int value)
{
u32 val;
val = 0x100 << GPIO_BIT(gpio);
if (value)
val |= 1 << GPIO_BIT(gpio);
tegra_gpio_writel(val, reg);
}
static void tegra_gpio_enable(int gpio)
{
tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 1);
}
static void tegra_gpio_disable(int gpio)
{
tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 0);
}
static int tegra_gpio_request(struct gpio_chip *chip, unsigned offset)
{
return pinctrl_request_gpio(offset);
}
static void tegra_gpio_free(struct gpio_chip *chip, unsigned offset)
{
pinctrl_free_gpio(offset);
tegra_gpio_disable(offset);
}
static void tegra_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
tegra_gpio_mask_write(GPIO_MSK_OUT(offset), offset, value);
}
static int tegra_gpio_get(struct gpio_chip *chip, unsigned offset)
{
/* If gpio is in output mode then read from the out value */
if ((tegra_gpio_readl(GPIO_OE(offset)) >> GPIO_BIT(offset)) & 1)
return (tegra_gpio_readl(GPIO_OUT(offset)) >>
GPIO_BIT(offset)) & 0x1;
return (tegra_gpio_readl(GPIO_IN(offset)) >> GPIO_BIT(offset)) & 0x1;
}
static int tegra_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
tegra_gpio_mask_write(GPIO_MSK_OE(offset), offset, 0);
tegra_gpio_enable(offset);
return 0;
}
static int tegra_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
int value)
{
tegra_gpio_set(chip, offset, value);
tegra_gpio_mask_write(GPIO_MSK_OE(offset), offset, 1);
tegra_gpio_enable(offset);
return 0;
}
static int tegra_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
return irq_find_mapping(irq_domain, offset);
}
static struct gpio_chip tegra_gpio_chip = {
.label = "tegra-gpio",
.request = tegra_gpio_request,
.free = tegra_gpio_free,
.direction_input = tegra_gpio_direction_input,
.get = tegra_gpio_get,
.direction_output = tegra_gpio_direction_output,
.set = tegra_gpio_set,
.to_irq = tegra_gpio_to_irq,
.base = 0,
};
static void tegra_gpio_irq_ack(struct irq_data *d)
{
int gpio = d->hwirq;
tegra_gpio_writel(1 << GPIO_BIT(gpio), GPIO_INT_CLR(gpio));
}
static void tegra_gpio_irq_mask(struct irq_data *d)
{
int gpio = d->hwirq;
tegra_gpio_mask_write(GPIO_MSK_INT_ENB(gpio), gpio, 0);
}
static void tegra_gpio_irq_unmask(struct irq_data *d)
{
int gpio = d->hwirq;
tegra_gpio_mask_write(GPIO_MSK_INT_ENB(gpio), gpio, 1);
}
static int tegra_gpio_irq_set_type(struct irq_data *d, unsigned int type)
{
int gpio = d->hwirq;
struct tegra_gpio_bank *bank = irq_data_get_irq_chip_data(d);
int port = GPIO_PORT(gpio);
int lvl_type;
int val;
unsigned long flags;
int ret;
switch (type & IRQ_TYPE_SENSE_MASK) {
case IRQ_TYPE_EDGE_RISING:
lvl_type = GPIO_INT_LVL_EDGE_RISING;
break;
case IRQ_TYPE_EDGE_FALLING:
lvl_type = GPIO_INT_LVL_EDGE_FALLING;
break;
case IRQ_TYPE_EDGE_BOTH:
lvl_type = GPIO_INT_LVL_EDGE_BOTH;
break;
case IRQ_TYPE_LEVEL_HIGH:
lvl_type = GPIO_INT_LVL_LEVEL_HIGH;
break;
case IRQ_TYPE_LEVEL_LOW:
lvl_type = GPIO_INT_LVL_LEVEL_LOW;
break;
default:
return -EINVAL;
}
ret = gpio_lock_as_irq(&tegra_gpio_chip, gpio);
if (ret) {
dev_err(dev, "unable to lock Tegra GPIO %d as IRQ\n", gpio);
return ret;
}
spin_lock_irqsave(&bank->lvl_lock[port], flags);
val = tegra_gpio_readl(GPIO_INT_LVL(gpio));
val &= ~(GPIO_INT_LVL_MASK << GPIO_BIT(gpio));
val |= lvl_type << GPIO_BIT(gpio);
tegra_gpio_writel(val, GPIO_INT_LVL(gpio));
spin_unlock_irqrestore(&bank->lvl_lock[port], flags);
tegra_gpio_mask_write(GPIO_MSK_OE(gpio), gpio, 0);
tegra_gpio_enable(gpio);
if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
__irq_set_handler_locked(d->irq, handle_level_irq);
else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
__irq_set_handler_locked(d->irq, handle_edge_irq);
return 0;
}
static void tegra_gpio_irq_shutdown(struct irq_data *d)
{
int gpio = d->hwirq;
gpio_unlock_as_irq(&tegra_gpio_chip, gpio);
}
static void tegra_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
{
struct tegra_gpio_bank *bank;
int port;
int pin;
int unmasked = 0;
struct irq_chip *chip = irq_desc_get_chip(desc);
chained_irq_enter(chip, desc);
bank = irq_get_handler_data(irq);
for (port = 0; port < 4; port++) {
int gpio = tegra_gpio_compose(bank->bank, port, 0);
unsigned long sta = tegra_gpio_readl(GPIO_INT_STA(gpio)) &
tegra_gpio_readl(GPIO_INT_ENB(gpio));
u32 lvl = tegra_gpio_readl(GPIO_INT_LVL(gpio));
for_each_set_bit(pin, &sta, 8) {
tegra_gpio_writel(1 << pin, GPIO_INT_CLR(gpio));
/* if gpio is edge triggered, clear condition
* before executing the hander so that we don't
* miss edges
*/
if (lvl & (0x100 << pin)) {
unmasked = 1;
chained_irq_exit(chip, desc);
}
generic_handle_irq(gpio_to_irq(gpio + pin));
}
}
if (!unmasked)
chained_irq_exit(chip, desc);
}
#ifdef CONFIG_PM_SLEEP
static int tegra_gpio_resume(struct device *dev)
{
unsigned long flags;
int b;
int p;
local_irq_save(flags);
for (b = 0; b < tegra_gpio_bank_count; b++) {
struct tegra_gpio_bank *bank = &tegra_gpio_banks[b];
for (p = 0; p < ARRAY_SIZE(bank->oe); p++) {
unsigned int gpio = (b<<5) | (p<<3);
tegra_gpio_writel(bank->cnf[p], GPIO_CNF(gpio));
tegra_gpio_writel(bank->out[p], GPIO_OUT(gpio));
tegra_gpio_writel(bank->oe[p], GPIO_OE(gpio));
tegra_gpio_writel(bank->int_lvl[p], GPIO_INT_LVL(gpio));
tegra_gpio_writel(bank->int_enb[p], GPIO_INT_ENB(gpio));
}
}
local_irq_restore(flags);
return 0;
}
static int tegra_gpio_suspend(struct device *dev)
{
unsigned long flags;
int b;
int p;
local_irq_save(flags);
for (b = 0; b < tegra_gpio_bank_count; b++) {
struct tegra_gpio_bank *bank = &tegra_gpio_banks[b];
for (p = 0; p < ARRAY_SIZE(bank->oe); p++) {
unsigned int gpio = (b<<5) | (p<<3);
bank->cnf[p] = tegra_gpio_readl(GPIO_CNF(gpio));
bank->out[p] = tegra_gpio_readl(GPIO_OUT(gpio));
bank->oe[p] = tegra_gpio_readl(GPIO_OE(gpio));
bank->int_enb[p] = tegra_gpio_readl(GPIO_INT_ENB(gpio));
bank->int_lvl[p] = tegra_gpio_readl(GPIO_INT_LVL(gpio));
/* Enable gpio irq for wake up source */
tegra_gpio_writel(bank->wake_enb[p],
GPIO_INT_ENB(gpio));
}
}
local_irq_restore(flags);
return 0;
}
static int tegra_gpio_irq_set_wake(struct irq_data *d, unsigned int enable)
{
struct tegra_gpio_bank *bank = irq_data_get_irq_chip_data(d);
int gpio = d->hwirq;
u32 port, bit, mask;
port = GPIO_PORT(gpio);
bit = GPIO_BIT(gpio);
mask = BIT(bit);
if (enable)
bank->wake_enb[port] |= mask;
else
bank->wake_enb[port] &= ~mask;
return irq_set_irq_wake(bank->irq, enable);
}
#endif
static struct irq_chip tegra_gpio_irq_chip = {
.name = "GPIO",
.irq_ack = tegra_gpio_irq_ack,
.irq_mask = tegra_gpio_irq_mask,
.irq_unmask = tegra_gpio_irq_unmask,
.irq_set_type = tegra_gpio_irq_set_type,
.irq_shutdown = tegra_gpio_irq_shutdown,
#ifdef CONFIG_PM_SLEEP
.irq_set_wake = tegra_gpio_irq_set_wake,
#endif
};
static const struct dev_pm_ops tegra_gpio_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(tegra_gpio_suspend, tegra_gpio_resume)
};
struct tegra_gpio_soc_config {
u32 bank_stride;
u32 upper_offset;
};
static struct tegra_gpio_soc_config tegra20_gpio_config = {
.bank_stride = 0x80,
.upper_offset = 0x800,
};
static struct tegra_gpio_soc_config tegra30_gpio_config = {
.bank_stride = 0x100,
.upper_offset = 0x80,
};
static struct of_device_id tegra_gpio_of_match[] = {
{ .compatible = "nvidia,tegra30-gpio", .data = &tegra30_gpio_config },
{ .compatible = "nvidia,tegra20-gpio", .data = &tegra20_gpio_config },
{ },
};
/* This lock class tells lockdep that GPIO irqs are in a different
* category than their parents, so it won't report false recursion.
*/
static struct lock_class_key gpio_lock_class;
static int tegra_gpio_probe(struct platform_device *pdev)
{
const struct of_device_id *match;
struct tegra_gpio_soc_config *config;
struct resource *res;
struct tegra_gpio_bank *bank;
int ret;
int gpio;
int i;
int j;
dev = &pdev->dev;
match = of_match_device(tegra_gpio_of_match, &pdev->dev);
if (!match) {
dev_err(&pdev->dev, "Error: No device match found\n");
return -ENODEV;
}
config = (struct tegra_gpio_soc_config *)match->data;
tegra_gpio_bank_stride = config->bank_stride;
tegra_gpio_upper_offset = config->upper_offset;
for (;;) {
res = platform_get_resource(pdev, IORESOURCE_IRQ, tegra_gpio_bank_count);
if (!res)
break;
tegra_gpio_bank_count++;
}
if (!tegra_gpio_bank_count) {
dev_err(&pdev->dev, "Missing IRQ resource\n");
return -ENODEV;
}
tegra_gpio_chip.ngpio = tegra_gpio_bank_count * 32;
tegra_gpio_banks = devm_kzalloc(&pdev->dev,
tegra_gpio_bank_count * sizeof(*tegra_gpio_banks),
GFP_KERNEL);
if (!tegra_gpio_banks) {
dev_err(&pdev->dev, "Couldn't allocate bank structure\n");
return -ENODEV;
}
irq_domain = irq_domain_add_linear(pdev->dev.of_node,
tegra_gpio_chip.ngpio,
&irq_domain_simple_ops, NULL);
if (!irq_domain)
return -ENODEV;
for (i = 0; i < tegra_gpio_bank_count; i++) {
res = platform_get_resource(pdev, IORESOURCE_IRQ, i);
if (!res) {
dev_err(&pdev->dev, "Missing IRQ resource\n");
return -ENODEV;
}
bank = &tegra_gpio_banks[i];
bank->bank = i;
bank->irq = res->start;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
regs = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(regs))
return PTR_ERR(regs);
for (i = 0; i < tegra_gpio_bank_count; i++) {
for (j = 0; j < 4; j++) {
int gpio = tegra_gpio_compose(i, j, 0);
tegra_gpio_writel(0x00, GPIO_INT_ENB(gpio));
}
}
tegra_gpio_chip.of_node = pdev->dev.of_node;
ret = gpiochip_add(&tegra_gpio_chip);
if (ret < 0) {
irq_domain_remove(irq_domain);
return ret;
}
for (gpio = 0; gpio < tegra_gpio_chip.ngpio; gpio++) {
int irq = irq_create_mapping(irq_domain, gpio);
/* No validity check; all Tegra GPIOs are valid IRQs */
bank = &tegra_gpio_banks[GPIO_BANK(gpio)];
irq_set_lockdep_class(irq, &gpio_lock_class);
irq_set_chip_data(irq, bank);
irq_set_chip_and_handler(irq, &tegra_gpio_irq_chip,
handle_simple_irq);
set_irq_flags(irq, IRQF_VALID);
}
for (i = 0; i < tegra_gpio_bank_count; i++) {
bank = &tegra_gpio_banks[i];
irq_set_chained_handler(bank->irq, tegra_gpio_irq_handler);
irq_set_handler_data(bank->irq, bank);
for (j = 0; j < 4; j++)
spin_lock_init(&bank->lvl_lock[j]);
}
return 0;
}
static struct platform_driver tegra_gpio_driver = {
.driver = {
.name = "tegra-gpio",
.owner = THIS_MODULE,
.pm = &tegra_gpio_pm_ops,
.of_match_table = tegra_gpio_of_match,
},
.probe = tegra_gpio_probe,
};
static int __init tegra_gpio_init(void)
{
return platform_driver_register(&tegra_gpio_driver);
}
postcore_initcall(tegra_gpio_init);
#ifdef CONFIG_DEBUG_FS
#include <linux/debugfs.h>
#include <linux/seq_file.h>
static int dbg_gpio_show(struct seq_file *s, void *unused)
{
int i;
int j;
for (i = 0; i < tegra_gpio_bank_count; i++) {
for (j = 0; j < 4; j++) {
int gpio = tegra_gpio_compose(i, j, 0);
seq_printf(s,
"%d:%d %02x %02x %02x %02x %02x %02x %06x\n",
i, j,
tegra_gpio_readl(GPIO_CNF(gpio)),
tegra_gpio_readl(GPIO_OE(gpio)),
tegra_gpio_readl(GPIO_OUT(gpio)),
tegra_gpio_readl(GPIO_IN(gpio)),
tegra_gpio_readl(GPIO_INT_STA(gpio)),
tegra_gpio_readl(GPIO_INT_ENB(gpio)),
tegra_gpio_readl(GPIO_INT_LVL(gpio)));
}
}
return 0;
}
static int dbg_gpio_open(struct inode *inode, struct file *file)
{
return single_open(file, dbg_gpio_show, &inode->i_private);
}
static const struct file_operations debug_fops = {
.open = dbg_gpio_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int __init tegra_gpio_debuginit(void)
{
(void) debugfs_create_file("tegra_gpio", S_IRUGO,
NULL, NULL, &debug_fops);
return 0;
}
late_initcall(tegra_gpio_debuginit);
#endif