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kernel-hacking-2024-linux-s.../arch/arm/mach-tegra/gpio.c
Olof Johansson 632095ea15 ARM: tegra: add tegra_gpio_table and tegra_gpio_config 
To give one place to setup the pins that are used as GPIOs instead
of as their pinmuxed functions. Specifying enabled as false explicitly
disables the gpio mode of that pin (if left on by firmware).

This should remove the need for calling these from specific drivers and
thus reduce tegra-specific code from them.

Signed-off-by: Olof Johansson <olof@lixom.net>
Acked-by: Erik Gilling <konkers@android.com>
2011-02-22 17:27:11 -08:00

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/*
* 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/init.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/gpio.h>
#include <mach/iomap.h>
#include <mach/suspend.h>
#define GPIO_BANK(x) ((x) >> 5)
#define GPIO_PORT(x) (((x) >> 3) & 0x3)
#define GPIO_BIT(x) ((x) & 0x7)
#define GPIO_REG(x) (IO_TO_VIRT(TEGRA_GPIO_BASE) + \
GPIO_BANK(x) * 0x80 + \
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) + 0x800)
#define GPIO_MSK_OE(x) (GPIO_REG(x) + 0x810)
#define GPIO_MSK_OUT(x) (GPIO_REG(x) + 0X820)
#define GPIO_MSK_INT_STA(x) (GPIO_REG(x) + 0x840)
#define GPIO_MSK_INT_ENB(x) (GPIO_REG(x) + 0x850)
#define GPIO_MSK_INT_LVL(x) (GPIO_REG(x) + 0x860)
#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
u32 cnf[4];
u32 out[4];
u32 oe[4];
u32 int_enb[4];
u32 int_lvl[4];
#endif
};
static struct tegra_gpio_bank tegra_gpio_banks[] = {
{.bank = 0, .irq = INT_GPIO1},
{.bank = 1, .irq = INT_GPIO2},
{.bank = 2, .irq = INT_GPIO3},
{.bank = 3, .irq = INT_GPIO4},
{.bank = 4, .irq = INT_GPIO5},
{.bank = 5, .irq = INT_GPIO6},
{.bank = 6, .irq = INT_GPIO7},
};
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);
__raw_writel(val, reg);
}
void tegra_gpio_enable(int gpio)
{
tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 1);
}
void tegra_gpio_disable(int gpio)
{
tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 0);
}
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)
{
return (__raw_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);
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);
return 0;
}
static struct gpio_chip tegra_gpio_chip = {
.label = "tegra-gpio",
.direction_input = tegra_gpio_direction_input,
.get = tegra_gpio_get,
.direction_output = tegra_gpio_direction_output,
.set = tegra_gpio_set,
.base = 0,
.ngpio = TEGRA_NR_GPIOS,
};
static void tegra_gpio_irq_ack(struct irq_data *d)
{
int gpio = d->irq - INT_GPIO_BASE;
__raw_writel(1 << GPIO_BIT(gpio), GPIO_INT_CLR(gpio));
}
static void tegra_gpio_irq_mask(struct irq_data *d)
{
int gpio = d->irq - INT_GPIO_BASE;
tegra_gpio_mask_write(GPIO_MSK_INT_ENB(gpio), gpio, 0);
}
static void tegra_gpio_irq_unmask(struct irq_data *d)
{
int gpio = d->irq - INT_GPIO_BASE;
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->irq - INT_GPIO_BASE;
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;
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;
}
spin_lock_irqsave(&bank->lvl_lock[port], flags);
val = __raw_readl(GPIO_INT_LVL(gpio));
val &= ~(GPIO_INT_LVL_MASK << GPIO_BIT(gpio));
val |= lvl_type << GPIO_BIT(gpio);
__raw_writel(val, GPIO_INT_LVL(gpio));
spin_unlock_irqrestore(&bank->lvl_lock[port], flags);
if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
__set_irq_handler_unlocked(d->irq, handle_level_irq);
else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
__set_irq_handler_unlocked(d->irq, handle_edge_irq);
return 0;
}
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;
desc->irq_data.chip->irq_ack(&desc->irq_data);
bank = get_irq_data(irq);
for (port = 0; port < 4; port++) {
int gpio = tegra_gpio_compose(bank->bank, port, 0);
unsigned long sta = __raw_readl(GPIO_INT_STA(gpio)) &
__raw_readl(GPIO_INT_ENB(gpio));
u32 lvl = __raw_readl(GPIO_INT_LVL(gpio));
for_each_set_bit(pin, &sta, 8) {
__raw_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;
desc->irq_data.chip->irq_unmask(&desc->irq_data);
}
generic_handle_irq(gpio_to_irq(gpio + pin));
}
}
if (!unmasked)
desc->irq_data.chip->irq_unmask(&desc->irq_data);
}
#ifdef CONFIG_PM
void tegra_gpio_resume(void)
{
unsigned long flags;
int b, p, i;
local_irq_save(flags);
for (b = 0; b < ARRAY_SIZE(tegra_gpio_banks); 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);
__raw_writel(bank->cnf[p], GPIO_CNF(gpio));
__raw_writel(bank->out[p], GPIO_OUT(gpio));
__raw_writel(bank->oe[p], GPIO_OE(gpio));
__raw_writel(bank->int_lvl[p], GPIO_INT_LVL(gpio));
__raw_writel(bank->int_enb[p], GPIO_INT_ENB(gpio));
}
}
local_irq_restore(flags);
for (i = INT_GPIO_BASE; i < (INT_GPIO_BASE + TEGRA_NR_GPIOS); i++) {
struct irq_desc *desc = irq_to_desc(i);
if (!desc || (desc->status & IRQ_WAKEUP))
continue;
enable_irq(i);
}
}
void tegra_gpio_suspend(void)
{
unsigned long flags;
int b, p, i;
for (i = INT_GPIO_BASE; i < (INT_GPIO_BASE + TEGRA_NR_GPIOS); i++) {
struct irq_desc *desc = irq_to_desc(i);
if (!desc)
continue;
if (desc->status & IRQ_WAKEUP) {
int gpio = i - INT_GPIO_BASE;
pr_debug("gpio %d.%d is wakeup\n", gpio/8, gpio&7);
continue;
}
disable_irq(i);
}
local_irq_save(flags);
for (b = 0; b < ARRAY_SIZE(tegra_gpio_banks); 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] = __raw_readl(GPIO_CNF(gpio));
bank->out[p] = __raw_readl(GPIO_OUT(gpio));
bank->oe[p] = __raw_readl(GPIO_OE(gpio));
bank->int_enb[p] = __raw_readl(GPIO_INT_ENB(gpio));
bank->int_lvl[p] = __raw_readl(GPIO_INT_LVL(gpio));
}
}
local_irq_restore(flags);
}
static int tegra_gpio_wake_enable(struct irq_data *d, unsigned int enable)
{
struct tegra_gpio_bank *bank = irq_data_get_irq_chip_data(d);
return 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,
#ifdef CONFIG_PM
.irq_set_wake = tegra_gpio_wake_enable,
#endif
};
/* 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 __init tegra_gpio_init(void)
{
struct tegra_gpio_bank *bank;
int i;
int j;
for (i = 0; i < 7; i++) {
for (j = 0; j < 4; j++) {
int gpio = tegra_gpio_compose(i, j, 0);
__raw_writel(0x00, GPIO_INT_ENB(gpio));
}
}
gpiochip_add(&tegra_gpio_chip);
for (i = INT_GPIO_BASE; i < (INT_GPIO_BASE + TEGRA_NR_GPIOS); i++) {
bank = &tegra_gpio_banks[GPIO_BANK(irq_to_gpio(i))];
lockdep_set_class(&irq_desc[i].lock, &gpio_lock_class);
set_irq_chip_data(i, bank);
set_irq_chip(i, &tegra_gpio_irq_chip);
set_irq_handler(i, handle_simple_irq);
set_irq_flags(i, IRQF_VALID);
}
for (i = 0; i < ARRAY_SIZE(tegra_gpio_banks); i++) {
bank = &tegra_gpio_banks[i];
set_irq_chained_handler(bank->irq, tegra_gpio_irq_handler);
set_irq_data(bank->irq, bank);
for (j = 0; j < 4; j++)
spin_lock_init(&bank->lvl_lock[j]);
}
return 0;
}
postcore_initcall(tegra_gpio_init);
void __init tegra_gpio_config(struct tegra_gpio_table *table, int num)
{
int i;
for (i = 0; i < num; i++) {
int gpio = table[i].gpio;
if (table[i].enable)
tegra_gpio_enable(gpio);
else
tegra_gpio_disable(gpio);
}
}
#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 < 7; 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,
__raw_readl(GPIO_CNF(gpio)),
__raw_readl(GPIO_OE(gpio)),
__raw_readl(GPIO_OUT(gpio)),
__raw_readl(GPIO_IN(gpio)),
__raw_readl(GPIO_INT_STA(gpio)),
__raw_readl(GPIO_INT_ENB(gpio)),
__raw_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
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