/*
* TI DaVinci GPIO Support
*
* Copyright (c) 2006 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/errno.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/bitops.h>
#include <mach/irqs.h>
#include <mach/hardware.h>
#include <mach/gpio.h>
#include <asm/mach/irq.h>
static DEFINE_SPINLOCK(gpio_lock);
static DECLARE_BITMAP(gpio_in_use, DAVINCI_N_GPIO);
int gpio_request(unsigned gpio, const char *tag)
{
if (gpio >= DAVINCI_N_GPIO)
return -EINVAL;
if (test_and_set_bit(gpio, gpio_in_use))
return -EBUSY;
return 0;
}
EXPORT_SYMBOL(gpio_request);
void gpio_free(unsigned gpio)
{
if (gpio >= DAVINCI_N_GPIO)
return;
clear_bit(gpio, gpio_in_use);
}
EXPORT_SYMBOL(gpio_free);
/* create a non-inlined version */
static struct gpio_controller *__iomem gpio2controller(unsigned gpio)
{
return __gpio_to_controller(gpio);
}
/*
* Assuming the pin is muxed as a gpio output, set its output value.
*/
void __gpio_set(unsigned gpio, int value)
{
struct gpio_controller *__iomem g = gpio2controller(gpio);
__raw_writel(__gpio_mask(gpio), value ? &g->set_data : &g->clr_data);
}
EXPORT_SYMBOL(__gpio_set);
/*
* 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.
*/
int __gpio_get(unsigned gpio)
{
struct gpio_controller *__iomem g = gpio2controller(gpio);
return !!(__gpio_mask(gpio) & __raw_readl(&g->in_data));
}
EXPORT_SYMBOL(__gpio_get);
/*--------------------------------------------------------------------------*/
/*
* board setup code *MUST* set PINMUX0 and PINMUX1 as
* needed, and enable the GPIO clock.
*/
int gpio_direction_input(unsigned gpio)
{
struct gpio_controller *__iomem g = gpio2controller(gpio);
u32 temp;
u32 mask;
if (!g)
return -EINVAL;
spin_lock(&gpio_lock);
mask = __gpio_mask(gpio);
temp = __raw_readl(&g->dir);
temp |= mask;
__raw_writel(temp, &g->dir);
spin_unlock(&gpio_lock);
return 0;
}
EXPORT_SYMBOL(gpio_direction_input);
int gpio_direction_output(unsigned gpio, int value)
{
struct gpio_controller *__iomem g = gpio2controller(gpio);
u32 temp;
u32 mask;
if (!g)
return -EINVAL;
spin_lock(&gpio_lock);
mask = __gpio_mask(gpio);
temp = __raw_readl(&g->dir);
temp &= ~mask;
__raw_writel(mask, value ? &g->set_data : &g->clr_data);
__raw_writel(temp, &g->dir);
spin_unlock(&gpio_lock);
return 0;
}
EXPORT_SYMBOL(gpio_direction_output);
/*
* 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: GPIO0..GPIO7 also have direct INTC hookups, which work in addition
* to their GPIOBNK0 irq (but with a bit less overhead). But we don't have
* a good way to hook those up ...
*
* All those INTC hookups (GPIO0..GPIO7 plus five IRQ banks) can also
* serve as EDMA event triggers.
*/
static void gpio_irq_disable(unsigned irq)
{
struct gpio_controller *__iomem g = get_irq_chip_data(irq);
u32 mask = __gpio_mask(irq_to_gpio(irq));
__raw_writel(mask, &g->clr_falling);
__raw_writel(mask, &g->clr_rising);
}
static void gpio_irq_enable(unsigned irq)
{
struct gpio_controller *__iomem g = get_irq_chip_data(irq);
u32 mask = __gpio_mask(irq_to_gpio(irq));
if (irq_desc[irq].status & IRQ_TYPE_EDGE_FALLING)
__raw_writel(mask, &g->set_falling);
if (irq_desc[irq].status & IRQ_TYPE_EDGE_RISING)
__raw_writel(mask, &g->set_rising);
}
static int gpio_irq_type(unsigned irq, unsigned trigger)
{
struct gpio_controller *__iomem g = get_irq_chip_data(irq);
u32 mask = __gpio_mask(irq_to_gpio(irq));
if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
return -EINVAL;
irq_desc[irq].status &= ~IRQ_TYPE_SENSE_MASK;
irq_desc[irq].status |= trigger;
__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;
}
static struct irq_chip gpio_irqchip = {
.name = "GPIO",
.enable = gpio_irq_enable,
.disable = gpio_irq_disable,
.set_type = gpio_irq_type,
};
static void
gpio_irq_handler(unsigned irq, struct irq_desc *desc)
{
struct gpio_controller *__iomem g = get_irq_chip_data(irq);
u32 mask = 0xffff;
/* we only care about one bank */
if (irq & 1)
mask <<= 16;
/* temporarily mask (level sensitive) parent IRQ */
desc->chip->ack(irq);
while (1) {
u32 status;
struct irq_desc *gpio;
int n;
int res;
/* ack any irqs */
status = __raw_readl(&g->intstat) & mask;
if (!status)
break;
__raw_writel(status, &g->intstat);
if (irq & 1)
status >>= 16;
/* now demux them to the right lowlevel handler */
n = (int)get_irq_data(irq);
gpio = &irq_desc[n];
while (status) {
res = ffs(status);
n += res;
gpio += res;
desc_handle_irq(n - 1, gpio - 1);
status >>= res;
}
}
desc->chip->unmask(irq);
/* now it may re-trigger */
}
/*
* NOTE: for suspend/resume, probably best to make a sysdev (and class)
* with its suspend/resume calls hooking into the 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
* can be set appropriately for GPIOV33 pins.
*/
static int __init davinci_gpio_irq_setup(void)
{
unsigned gpio, irq, bank;
struct clk *clk;
clk = clk_get(NULL, "gpio");
if (IS_ERR(clk)) {
printk(KERN_ERR "Error %ld getting gpio clock?\n",
PTR_ERR(clk));
return 0;
}
clk_enable(clk);
for (gpio = 0, irq = gpio_to_irq(0), bank = IRQ_GPIOBNK0;
gpio < DAVINCI_N_GPIO; bank++) {
struct gpio_controller *__iomem g = gpio2controller(gpio);
unsigned i;
__raw_writel(~0, &g->clr_falling);
__raw_writel(~0, &g->clr_rising);
/* set up all irqs in this bank */
set_irq_chained_handler(bank, gpio_irq_handler);
set_irq_chip_data(bank, g);
set_irq_data(bank, (void *)irq);
for (i = 0; i < 16 && gpio < DAVINCI_N_GPIO;
i++, irq++, gpio++) {
set_irq_chip(irq, &gpio_irqchip);
set_irq_chip_data(irq, g);
set_irq_handler(irq, handle_simple_irq);
set_irq_flags(irq, IRQF_VALID);
}
}
/* BINTEN -- per-bank interrupt enable. genirq would also let these
* bits be set/cleared dynamically.
*/
__raw_writel(0x1f, (void *__iomem)
IO_ADDRESS(DAVINCI_GPIO_BASE + 0x08));
printk(KERN_INFO "DaVinci: %d gpio irqs\n", irq - gpio_to_irq(0));
return 0;
}
arch_initcall(davinci_gpio_irq_setup);
