/*
* 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/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/cputype.h>
#include <mach/irqs.h>
#include <mach/hardware.h>
#include <mach/common.h>
#include <mach/gpio.h>
#include <asm/mach/irq.h>
static DEFINE_SPINLOCK(gpio_lock);
struct davinci_gpio {
struct gpio_chip chip;
struct gpio_controller *__iomem regs;
};
static struct davinci_gpio chips[DIV_ROUND_UP(DAVINCI_N_GPIO, 32)];
/* create a non-inlined version */
static struct gpio_controller __iomem * __init gpio2controller(unsigned gpio)
{
return __gpio_to_controller(gpio);
}
static int __init davinci_gpio_irq_setup(void);
/*--------------------------------------------------------------------------*/
/*
* board setup code *MUST* set PINMUX0 and PINMUX1 as
* needed, and enable the GPIO clock.
*/
static int davinci_direction_in(struct gpio_chip *chip, unsigned offset)
{
struct davinci_gpio *d = container_of(chip, struct davinci_gpio, chip);
struct gpio_controller *__iomem g = d->regs;
u32 temp;
spin_lock(&gpio_lock);
temp = __raw_readl(&g->dir);
temp |= (1 << offset);
__raw_writel(temp, &g->dir);
spin_unlock(&gpio_lock);
return 0;
}
/*
* 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 *d = container_of(chip, struct davinci_gpio, chip);
struct gpio_controller *__iomem g = d->regs;
return (1 << offset) & __raw_readl(&g->in_data);
}
static int
davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value)
{
struct davinci_gpio *d = container_of(chip, struct davinci_gpio, chip);
struct gpio_controller *__iomem g = d->regs;
u32 temp;
u32 mask = 1 << offset;
spin_lock(&gpio_lock);
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;
}
/*
* 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 *d = container_of(chip, struct davinci_gpio, chip);
struct gpio_controller *__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;
/*
* 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;
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;
chips[i].regs = gpio2controller(base);
gpiochip_add(&chips[i].chip);
}
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 but less flexibility
* on triggering (e.g. no edge options). We don't try to use those.
*
* All those INTC hookups (direct, plus several 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));
unsigned status = irq_desc[irq].status;
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(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;
/* don't enable the IRQ if it's currently disabled */
if (irq_desc[irq].depth == 0) {
__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->mask(irq);
desc->chip->ack(irq);
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);
if (irq & 1)
status >>= 16;
/* now demux them to the right lowlevel handler */
n = (int)get_irq_data(irq);
while (status) {
res = ffs(status);
n += res;
generic_handle_irq(n - 1);
status >>= res;
}
}
desc->chip->unmask(irq);
/* now it may re-trigger */
}
/*
* 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;
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_enable(clk);
for (gpio = 0, irq = gpio_to_irq(0), bank = 0;
gpio < ngpio;
bank++, bank_irq++) {
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_irq, gpio_irq_handler);
set_irq_chip_data(bank_irq, g);
set_irq_data(bank_irq, (void *)irq);
for (i = 0; i < 16 && gpio < ngpio; 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 |= BIT(bank);
}
/* BINTEN -- per-bank interrupt enable. genirq would also let these
* bits be set/cleared dynamically.
*/
__raw_writel(binten, soc_info->gpio_base + 0x08);
printk(KERN_INFO "DaVinci: %d gpio irqs\n", irq - gpio_to_irq(0));
return 0;
}
