- 根目录:
- drivers
- gpio
- gpio-davinci.c
/*
* TI DaVinci GPIO Support
*
* Copyright (c) 2006-2007 David Brownell
* Copyright (c) 2007, MontaVista Software, Inc. <source@mvista.com>
*
* 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.
*/
#include <linux/gpio.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <asm/mach/irq.h>
struct davinci_gpio_regs {
u32 dir;
u32 out_data;
u32 set_data;
u32 clr_data;
u32 in_data;
u32 set_rising;
u32 clr_rising;
u32 set_falling;
u32 clr_falling;
u32 intstat;
};
#define chip2controller(chip) \
container_of(chip, struct davinci_gpio_controller, chip)
static struct davinci_gpio_controller chips[DIV_ROUND_UP(DAVINCI_N_GPIO, 32)];
static void __iomem *gpio_base;
static struct davinci_gpio_regs __iomem __init *gpio2regs(unsigned gpio)
{
void __iomem *ptr;
if (gpio < 32 * 1)
ptr = gpio_base + 0x10;
else if (gpio < 32 * 2)
ptr = gpio_base + 0x38;
else if (gpio < 32 * 3)
ptr = gpio_base + 0x60;
else if (gpio < 32 * 4)
ptr = gpio_base + 0x88;
else if (gpio < 32 * 5)
ptr = gpio_base + 0xb0;
else
ptr = NULL;
return ptr;
}
static inline struct davinci_gpio_regs __iomem *irq2regs(int irq)
{
struct davinci_gpio_regs __iomem *g;
g = (__force struct davinci_gpio_regs __iomem *)irq_get_chip_data(irq);
return g;
}
static int __init davinci_gpio_irq_setup(void);
/*--------------------------------------------------------------------------*/
/* board setup code *MUST* setup pinmux and enable the GPIO clock. */
static inline int __davinci_direction(struct gpio_chip *chip,
unsigned offset, bool out, int value)
{
struct davinci_gpio_controller *d = chip2controller(chip);
struct davinci_gpio_regs __iomem *g = d->regs;
unsigned long flags;
u32 temp;
u32 mask = 1 << offset;
spin_lock_irqsave(&d->lock, flags);
temp = __raw_readl(&g->dir);
if (out) {
temp &= ~mask;
__raw_writel(mask, value ? &g->set_data : &g->clr_data);
} else {
temp |= mask;
}
__raw_writel(temp, &g->dir);
spin_unlock_irqrestore(&d->lock, flags);
return 0;
}
static int davinci_direction_in(struct gpio_chip *chip, unsigned offset)
{
return __davinci_direction(chip, offset, false, 0);
}
static int
davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value)
{
return __davinci_direction(chip, offset, true, value);
}
/*
* Read the pin's value (works even if it's set up as output);
* returns zero/nonzero.
*
* Note that changes are synched to the GPIO clock, so reading values back
* right after you've set them may give old values.
*/
static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct davinci_gpio_controller *d = chip2controller(chip);
struct davinci_gpio_regs __iomem *g = d->regs;
return (1 << offset) & __raw_readl(&g->in_data);
}
/*
* Assuming the pin is muxed as a gpio output, set its output value.
*/
static void
davinci_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct davinci_gpio_controller *d = chip2controller(chip);
struct davinci_gpio_regs __iomem *g = d->regs;
__raw_writel((1 << offset), value ? &g->set_data : &g->clr_data);
}
static int __init davinci_gpio_setup(void)
{
int i, base;
unsigned ngpio;
struct davinci_soc_info *soc_info = &davinci_soc_info;
struct davinci_gpio_regs *regs;
if (soc_info->gpio_type != GPIO_TYPE_DAVINCI)
return 0;
/*
* The gpio banks conceptually expose a segmented bitmap,
* and "ngpio" is one more than the largest zero-based
* bit index that's valid.
*/
ngpio = soc_info->gpio_num;
if (ngpio == 0) {
pr_err("GPIO setup: how many GPIOs?\n");
return -EINVAL;
}
if (WARN_ON(DAVINCI_N_GPIO < ngpio))
ngpio = DAVINCI_N_GPIO;
gpio_base = ioremap(soc_info->gpio_base, SZ_4K);
if (WARN_ON(!gpio_base))
return -ENOMEM;
for (i = 0, base = 0; base < ngpio; i++, base += 32) {
chips[i].chip.label = "DaVinci";
chips[i].chip.direction_input = davinci_direction_in;
chips[i].chip.get = davinci_gpio_get;
chips[i].chip.direction_output = davinci_direction_out;
chips[i].chip.set = davinci_gpio_set;
chips[i].chip.base = base;
chips[i].chip.ngpio = ngpio - base;
if (chips[i].chip.ngpio > 32)
chips[i].chip.ngpio = 32;
spin_lock_init(&chips[i].lock);
regs = gpio2regs(base);
chips[i].regs = regs;
chips[i].set_data = ®s->set_data;
chips[i].clr_data = ®s->clr_data;
chips[i].in_data = ®s->in_data;
gpiochip_add(&chips[i].chip);
}
soc_info->gpio_ctlrs = chips;
soc_info->gpio_ctlrs_num = DIV_ROUND_UP(ngpio, 32);
davinci_gpio_irq_setup();
return 0;
}
pure_initcall(davinci_gpio_setup);
/*--------------------------------------------------------------------------*/
/*
* We expect irqs will normally be set up as input pins, but they can also be
* used as output pins ... which is convenient for testing.
*
* NOTE: The first few GPIOs also have direct INTC hookups in addition
* to their GPIOBNK0 irq, with a bit less overhead.
*
* All those INTC hookups (direct, plus several IRQ banks) can also
* serve as EDMA event triggers.
*/
static void gpio_irq_disable(struct irq_data *d)
{
struct davinci_gpio_regs __iomem *g = irq2regs(d->irq);
u32 mask = (u32) irq_data_get_irq_handler_data(d);
__raw_writel(mask, &g->clr_falling);
__raw_writel(mask, &g->clr_rising);
}
static void gpio_irq_enable(struct irq_data *d)
{
struct davinci_gpio_regs __iomem *g = irq2regs(d->irq);
u32 mask = (u32) irq_data_get_irq_handler_data(d);
unsigned status = irqd_get_trigger_type(d);
status &= IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
if (!status)
status = IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
if (status & IRQ_TYPE_EDGE_FALLING)
__raw_writel(mask, &g->set_falling);
if (status & IRQ_TYPE_EDGE_RISING)
__raw_writel(mask, &g->set_rising);
}
static int gpio_irq_type(struct irq_data *d, unsigned trigger)
{
if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
return -EINVAL;
return 0;
}
static struct irq_chip gpio_irqchip = {
.name = "GPIO",
.irq_enable = gpio_irq_enable,
.irq_disable = gpio_irq_disable,
.irq_set_type = gpio_irq_type,
.flags = IRQCHIP_SET_TYPE_MASKED,
};
static void
gpio_irq_handler(unsigned irq, struct irq_desc *desc)
{
struct davinci_gpio_regs __iomem *g;
u32 mask = 0xffff;
struct davinci_gpio_controller *d;
d = (struct davinci_gpio_controller *)irq_desc_get_handler_data(desc);
g = (struct davinci_gpio_regs __iomem *)d->regs;
/* we only care about one bank */
if (irq & 1)
mask <<= 16;
/* temporarily mask (level sensitive) parent IRQ */
desc->irq_data.chip->irq_mask(&desc->irq_data);
desc->irq_data.chip->irq_ack(&desc->irq_data);
while (1) {
u32 status;
int n;
int res;
/* ack any irqs */
status = __raw_readl(&g->intstat) & mask;
if (!status)
break;
__raw_writel(status, &g->intstat);
/* now demux them to the right lowlevel handler */
n = d->irq_base;
if (irq & 1) {
n += 16;
status >>= 16;
}
while (status) {
res = ffs(status);
n += res;
generic_handle_irq(n - 1);
status >>= res;
}
}
desc->irq_data.chip->irq_unmask(&desc->irq_data);
/* now it may re-trigger */
}
static int gpio_to_irq_banked(struct gpio_chip *chip, unsigned offset)
{
struct davinci_gpio_controller *d = chip2controller(chip);
if (d->irq_base >= 0)
return d->irq_base + offset;
else
return -ENODEV;
}
static int gpio_to_irq_unbanked(struct gpio_chip *chip, unsigned offset)
{
struct davinci_soc_info *soc_info = &davinci_soc_info;
/* NOTE: we assume for now that only irqs in the first gpio_chip
* can provide direct-mapped IRQs to AINTC (up to 32 GPIOs).
*/
if (offset < soc_info->gpio_unbanked)
return soc_info->gpio_irq + offset;
else
return -ENODEV;
}
static int gpio_irq_type_unbanked(struct irq_data *data, unsigned trigger)
{
struct davinci_gpio_controller *d;
struct davinci_gpio_regs __iomem *g;
struct davinci_soc_info *soc_info = &davinci_soc_info;
u32 mask;
d = (struct davinci_gpio_controller *)data->handler_data;
g = (struct davinci_gpio_regs __iomem *)d->regs;
mask = __gpio_mask(data->irq - soc_info->gpio_irq);
if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
return -EINVAL;
__raw_writel(mask, (trigger & IRQ_TYPE_EDGE_FALLING)
? &g->set_falling : &g->clr_falling);
__raw_writel(mask, (trigger & IRQ_TYPE_EDGE_RISING)
? &g->set_rising : &g->clr_rising);
return 0;
}
/*
* NOTE: for suspend/resume, probably best to make a platform_device with
* suspend_late/resume_resume calls hooking into results of the set_wake()
* calls ... so if no gpios are wakeup events the clock can be disabled,
* with outputs left at previously set levels, and so that VDD3P3V.IOPWDN0
* (dm6446) can be set appropriately for GPIOV33 pins.
*/
static int __init davinci_gpio_irq_setup(void)
{
unsigned gpio, irq, bank;
struct clk *clk;
u32 binten = 0;
unsigned ngpio, bank_irq;
struct davinci_soc_info *soc_info = &davinci_soc_info;
struct davinci_gpio_regs __iomem *g;
ngpio = soc_info->gpio_num;
bank_irq = soc_info->gpio_irq;
if (bank_irq == 0) {
printk(KERN_ERR "Don't know first GPIO bank IRQ.\n");
return -EINVAL;
}
clk = clk_get(NULL, "gpio");
if (IS_ERR(clk)) {
printk(KERN_ERR "Error %ld getting gpio clock?\n",
PTR_ERR(clk));
return PTR_ERR(clk);
}
clk_prepare_enable(clk);
/* Arrange gpio_to_irq() support, handling either direct IRQs or
* banked IRQs. Having GPIOs in the first GPIO bank use direct
* IRQs, while the others use banked IRQs, would need some setup
* tweaks to recognize hardware which can do that.
*/
for (gpio = 0, bank = 0; gpio < ngpio; bank++, gpio += 32) {
chips[bank].chip.to_irq = gpio_to_irq_banked;
chips[bank].irq_base = soc_info->gpio_unbanked
? -EINVAL
: (soc_info->intc_irq_num + gpio);
}
/*
* AINTC can handle direct/unbanked IRQs for GPIOs, with the GPIO
* controller only handling trigger modes. We currently assume no
* IRQ mux conflicts; gpio_irq_type_unbanked() is only for GPIOs.
*/
if (soc_info->gpio_unbanked) {
static struct irq_chip_type gpio_unbanked;
/* pass "bank 0" GPIO IRQs to AINTC */
chips[0].chip.to_irq = gpio_to_irq_unbanked;
binten = BIT(0);
/* AINTC handles mask/unmask; GPIO handles triggering */
irq = bank_irq;
gpio_unbanked = *container_of(irq_get_chip(irq),
struct irq_chip_type, chip);
gpio_unbanked.chip.name = "GPIO-AINTC";
gpio_unbanked.chip.irq_set_type = gpio_irq_type_unbanked;
/* default trigger: both edges */
g = gpio2regs(0);
__raw_writel(~0, &g->set_falling);
__raw_writel(~0, &g->set_rising);
/* set the direct IRQs up to use that irqchip */
for (gpio = 0; gpio < soc_info->gpio_unbanked; gpio++, irq++) {
irq_set_chip(irq, &gpio_unbanked.chip);
irq_set_handler_data(irq, &chips[gpio / 32]);
irq_set_status_flags(irq, IRQ_TYPE_EDGE_BOTH);
}
goto done;
}
/*
* Or, AINTC can handle IRQs for banks of 16 GPIO IRQs, which we
* then chain through our own handler.
*/
for (gpio = 0, irq = gpio_to_irq(0), bank = 0;
gpio < ngpio;
bank++, bank_irq++) {
unsigned i;
/* disabled by default, enabled only as needed */
g = gpio2regs(gpio);
__raw_writel(~0, &g->clr_falling);
__raw_writel(~0, &g->clr_rising);
/* set up all irqs in this bank */
irq_set_chained_handler(bank_irq, gpio_irq_handler);
/*
* Each chip handles 32 gpios, and each irq bank consists of 16
* gpio irqs. Pass the irq bank's corresponding controller to
* the chained irq handler.
*/
irq_set_handler_data(bank_irq, &chips[gpio / 32]);
for (i = 0; i < 16 && gpio < ngpio; i++, irq++, gpio++) {
irq_set_chip(irq, &gpio_irqchip);
irq_set_chip_data(irq, (__force void *)g);
irq_set_handler_data(irq, (void *)__gpio_mask(gpio));
irq_set_handler(irq, handle_simple_irq);
set_irq_flags(irq, IRQF_VALID);
}
binten |= BIT(bank);
}
done:
/* BINTEN -- per-bank interrupt enable. genirq would also let these
* bits be set/cleared dynamically.
*/
__raw_writel(binten, gpio_base + 0x08);
printk(KERN_INFO "DaVinci: %d gpio irqs\n", irq - gpio_to_irq(0));
return 0;
}