linux/arch/arm/mach-davinci/gpio.c
David Brownell 7a36071e79 davinci: dm365 gpio irq support
Support DM365 GPIOs ... primarily by handling non-banked GPIO IRQs:

 - Flag DM365 chips as using non-banked GPIO interrupts, using a
   new soc_info field.

 - Replace the gpio_to_irq() mapping logic.  This now uses some
   runtime infrastructure, keyed off that new soc_info field,
   which doesn't handle irq_to_gpio().

 - Provide a new irq_chip ... GPIO IRQs handled directly by AINTC
   still need edge triggering managed by the GPIO controller.

DM365 chips no longer falsely report 104 GPIO IRQs as they boot.

Intelligence about IRQ muxing is missing, so for the moment this
only exposes the first eight DM365 GPIOs, which are never muxed.
The next eight are muxed, half with Ethernet (which uses most of
those pins anyway).

Tested on DM355 (10 unbanked IRQs _or_ 104 banked ones) and also
on DM365 (16 unbanked ones, only 8 made available).

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-08-26 10:57:00 +03:00

421 lines
11 KiB
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/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;
int irq_base;
};
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.
*
* 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 = (u32) get_irq_data(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 = (u32) get_irq_data(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 = (u32) get_irq_data(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 */
}
static int gpio_to_irq_banked(struct gpio_chip *chip, unsigned offset)
{
struct davinci_gpio *d = container_of(chip, struct davinci_gpio, 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(unsigned irq, unsigned trigger)
{
struct gpio_controller *__iomem g = get_irq_chip_data(irq);
u32 mask = (u32) get_irq_data(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 gpio_controller *__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_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 gpio_irqchip_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_irqchip_unbanked = *get_irq_desc_chip(irq_to_desc(irq));
gpio_irqchip_unbanked.name = "GPIO-AINTC";
gpio_irqchip_unbanked.set_type = gpio_irq_type_unbanked;
/* default trigger: both edges */
g = gpio2controller(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++) {
set_irq_chip(irq, &gpio_irqchip_unbanked);
set_irq_data(irq, (void *) __gpio_mask(gpio));
set_irq_chip_data(irq, g);
irq_desc[irq].status |= 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 = gpio2controller(gpio);
__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_data(irq, (void *) __gpio_mask(gpio));
set_irq_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, soc_info->gpio_base + 0x08);
printk(KERN_INFO "DaVinci: %d gpio irqs\n", irq - gpio_to_irq(0));
return 0;
}