https://github.com/torvalds/linux
Tip revision: 455c6fdbd219161bd09b1165f11699d6d73de11c authored by Linus Torvalds on 31 March 2014, 03:40:15 UTC
Linux 3.14
Linux 3.14
Tip revision: 455c6fd
gpio.c
/*
* linux/arch/arm/mach-at91/gpio.c
*
* Copyright (C) 2005 HP Labs
*
* 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/clk.h>
#include <linux/errno.h>
#include <linux/device.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/irqdomain.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/of_address.h>
#include <mach/hardware.h>
#include <mach/at91_pio.h>
#include "generic.h"
#define MAX_NB_GPIO_PER_BANK 32
struct at91_gpio_chip {
struct gpio_chip chip;
struct at91_gpio_chip *next; /* Bank sharing same clock */
int pioc_hwirq; /* PIO bank interrupt identifier on AIC */
int pioc_virq; /* PIO bank Linux virtual interrupt */
int pioc_idx; /* PIO bank index */
void __iomem *regbase; /* PIO bank virtual address */
struct clk *clock; /* associated clock */
struct irq_domain *domain; /* associated irq domain */
};
#define to_at91_gpio_chip(c) container_of(c, struct at91_gpio_chip, chip)
static int at91_gpiolib_request(struct gpio_chip *chip, unsigned offset);
static void at91_gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip);
static void at91_gpiolib_set(struct gpio_chip *chip, unsigned offset, int val);
static int at91_gpiolib_get(struct gpio_chip *chip, unsigned offset);
static int at91_gpiolib_direction_output(struct gpio_chip *chip,
unsigned offset, int val);
static int at91_gpiolib_direction_input(struct gpio_chip *chip,
unsigned offset);
static int at91_gpiolib_to_irq(struct gpio_chip *chip, unsigned offset);
#define AT91_GPIO_CHIP(name) \
{ \
.chip = { \
.label = name, \
.request = at91_gpiolib_request, \
.direction_input = at91_gpiolib_direction_input, \
.direction_output = at91_gpiolib_direction_output, \
.get = at91_gpiolib_get, \
.set = at91_gpiolib_set, \
.dbg_show = at91_gpiolib_dbg_show, \
.to_irq = at91_gpiolib_to_irq, \
.ngpio = MAX_NB_GPIO_PER_BANK, \
}, \
}
static struct at91_gpio_chip gpio_chip[] = {
AT91_GPIO_CHIP("pioA"),
AT91_GPIO_CHIP("pioB"),
AT91_GPIO_CHIP("pioC"),
AT91_GPIO_CHIP("pioD"),
AT91_GPIO_CHIP("pioE"),
};
static int gpio_banks;
static unsigned long at91_gpio_caps;
/* All PIO controllers support PIO3 features */
#define AT91_GPIO_CAP_PIO3 (1 << 0)
#define has_pio3() (at91_gpio_caps & AT91_GPIO_CAP_PIO3)
/*--------------------------------------------------------------------------*/
static inline void __iomem *pin_to_controller(unsigned pin)
{
pin /= MAX_NB_GPIO_PER_BANK;
if (likely(pin < gpio_banks))
return gpio_chip[pin].regbase;
return NULL;
}
static inline unsigned pin_to_mask(unsigned pin)
{
return 1 << (pin % MAX_NB_GPIO_PER_BANK);
}
static char peripheral_function(void __iomem *pio, unsigned mask)
{
char ret = 'X';
u8 select;
if (pio) {
if (has_pio3()) {
select = !!(__raw_readl(pio + PIO_ABCDSR1) & mask);
select |= (!!(__raw_readl(pio + PIO_ABCDSR2) & mask) << 1);
ret = 'A' + select;
} else {
ret = __raw_readl(pio + PIO_ABSR) & mask ?
'B' : 'A';
}
}
return ret;
}
/*--------------------------------------------------------------------------*/
/* Not all hardware capabilities are exposed through these calls; they
* only encapsulate the most common features and modes. (So if you
* want to change signals in groups, do it directly.)
*
* Bootloaders will usually handle some of the pin multiplexing setup.
* The intent is certainly that by the time Linux is fully booted, all
* pins should have been fully initialized. These setup calls should
* only be used by board setup routines, or possibly in driver probe().
*
* For bootloaders doing all that setup, these calls could be inlined
* as NOPs so Linux won't duplicate any setup code
*/
/*
* mux the pin to the "GPIO" peripheral role.
*/
int __init_or_module at91_set_GPIO_periph(unsigned pin, int use_pullup)
{
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
if (!pio)
return -EINVAL;
__raw_writel(mask, pio + PIO_IDR);
__raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
__raw_writel(mask, pio + PIO_PER);
return 0;
}
EXPORT_SYMBOL(at91_set_GPIO_periph);
/*
* mux the pin to the "A" internal peripheral role.
*/
int __init_or_module at91_set_A_periph(unsigned pin, int use_pullup)
{
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
if (!pio)
return -EINVAL;
__raw_writel(mask, pio + PIO_IDR);
__raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
if (has_pio3()) {
__raw_writel(__raw_readl(pio + PIO_ABCDSR1) & ~mask,
pio + PIO_ABCDSR1);
__raw_writel(__raw_readl(pio + PIO_ABCDSR2) & ~mask,
pio + PIO_ABCDSR2);
} else {
__raw_writel(mask, pio + PIO_ASR);
}
__raw_writel(mask, pio + PIO_PDR);
return 0;
}
EXPORT_SYMBOL(at91_set_A_periph);
/*
* mux the pin to the "B" internal peripheral role.
*/
int __init_or_module at91_set_B_periph(unsigned pin, int use_pullup)
{
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
if (!pio)
return -EINVAL;
__raw_writel(mask, pio + PIO_IDR);
__raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
if (has_pio3()) {
__raw_writel(__raw_readl(pio + PIO_ABCDSR1) | mask,
pio + PIO_ABCDSR1);
__raw_writel(__raw_readl(pio + PIO_ABCDSR2) & ~mask,
pio + PIO_ABCDSR2);
} else {
__raw_writel(mask, pio + PIO_BSR);
}
__raw_writel(mask, pio + PIO_PDR);
return 0;
}
EXPORT_SYMBOL(at91_set_B_periph);
/*
* mux the pin to the "C" internal peripheral role.
*/
int __init_or_module at91_set_C_periph(unsigned pin, int use_pullup)
{
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
if (!pio || !has_pio3())
return -EINVAL;
__raw_writel(mask, pio + PIO_IDR);
__raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
__raw_writel(__raw_readl(pio + PIO_ABCDSR1) & ~mask, pio + PIO_ABCDSR1);
__raw_writel(__raw_readl(pio + PIO_ABCDSR2) | mask, pio + PIO_ABCDSR2);
__raw_writel(mask, pio + PIO_PDR);
return 0;
}
EXPORT_SYMBOL(at91_set_C_periph);
/*
* mux the pin to the "D" internal peripheral role.
*/
int __init_or_module at91_set_D_periph(unsigned pin, int use_pullup)
{
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
if (!pio || !has_pio3())
return -EINVAL;
__raw_writel(mask, pio + PIO_IDR);
__raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
__raw_writel(__raw_readl(pio + PIO_ABCDSR1) | mask, pio + PIO_ABCDSR1);
__raw_writel(__raw_readl(pio + PIO_ABCDSR2) | mask, pio + PIO_ABCDSR2);
__raw_writel(mask, pio + PIO_PDR);
return 0;
}
EXPORT_SYMBOL(at91_set_D_periph);
/*
* mux the pin to the gpio controller (instead of "A", "B", "C"
* or "D" peripheral), and configure it for an input.
*/
int __init_or_module at91_set_gpio_input(unsigned pin, int use_pullup)
{
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
if (!pio)
return -EINVAL;
__raw_writel(mask, pio + PIO_IDR);
__raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
__raw_writel(mask, pio + PIO_ODR);
__raw_writel(mask, pio + PIO_PER);
return 0;
}
EXPORT_SYMBOL(at91_set_gpio_input);
/*
* mux the pin to the gpio controller (instead of "A", "B", "C"
* or "D" peripheral), and configure it for an output.
*/
int __init_or_module at91_set_gpio_output(unsigned pin, int value)
{
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
if (!pio)
return -EINVAL;
__raw_writel(mask, pio + PIO_IDR);
__raw_writel(mask, pio + PIO_PUDR);
__raw_writel(mask, pio + (value ? PIO_SODR : PIO_CODR));
__raw_writel(mask, pio + PIO_OER);
__raw_writel(mask, pio + PIO_PER);
return 0;
}
EXPORT_SYMBOL(at91_set_gpio_output);
/*
* enable/disable the glitch filter; mostly used with IRQ handling.
*/
int __init_or_module at91_set_deglitch(unsigned pin, int is_on)
{
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
if (!pio)
return -EINVAL;
if (has_pio3() && is_on)
__raw_writel(mask, pio + PIO_IFSCDR);
__raw_writel(mask, pio + (is_on ? PIO_IFER : PIO_IFDR));
return 0;
}
EXPORT_SYMBOL(at91_set_deglitch);
/*
* enable/disable the debounce filter;
*/
int __init_or_module at91_set_debounce(unsigned pin, int is_on, int div)
{
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
if (!pio || !has_pio3())
return -EINVAL;
if (is_on) {
__raw_writel(mask, pio + PIO_IFSCER);
__raw_writel(div & PIO_SCDR_DIV, pio + PIO_SCDR);
__raw_writel(mask, pio + PIO_IFER);
} else {
__raw_writel(mask, pio + PIO_IFDR);
}
return 0;
}
EXPORT_SYMBOL(at91_set_debounce);
/*
* enable/disable the multi-driver; This is only valid for output and
* allows the output pin to run as an open collector output.
*/
int __init_or_module at91_set_multi_drive(unsigned pin, int is_on)
{
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
if (!pio)
return -EINVAL;
__raw_writel(mask, pio + (is_on ? PIO_MDER : PIO_MDDR));
return 0;
}
EXPORT_SYMBOL(at91_set_multi_drive);
/*
* enable/disable the pull-down.
* If pull-up already enabled while calling the function, we disable it.
*/
int __init_or_module at91_set_pulldown(unsigned pin, int is_on)
{
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
if (!pio || !has_pio3())
return -EINVAL;
/* Disable pull-up anyway */
__raw_writel(mask, pio + PIO_PUDR);
__raw_writel(mask, pio + (is_on ? PIO_PPDER : PIO_PPDDR));
return 0;
}
EXPORT_SYMBOL(at91_set_pulldown);
/*
* disable Schmitt trigger
*/
int __init_or_module at91_disable_schmitt_trig(unsigned pin)
{
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
if (!pio || !has_pio3())
return -EINVAL;
__raw_writel(__raw_readl(pio + PIO_SCHMITT) | mask, pio + PIO_SCHMITT);
return 0;
}
EXPORT_SYMBOL(at91_disable_schmitt_trig);
/*
* assuming the pin is muxed as a gpio output, set its value.
*/
int at91_set_gpio_value(unsigned pin, int value)
{
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
if (!pio)
return -EINVAL;
__raw_writel(mask, pio + (value ? PIO_SODR : PIO_CODR));
return 0;
}
EXPORT_SYMBOL(at91_set_gpio_value);
/*
* read the pin's value (works even if it's not muxed as a gpio).
*/
int at91_get_gpio_value(unsigned pin)
{
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
u32 pdsr;
if (!pio)
return -EINVAL;
pdsr = __raw_readl(pio + PIO_PDSR);
return (pdsr & mask) != 0;
}
EXPORT_SYMBOL(at91_get_gpio_value);
/*--------------------------------------------------------------------------*/
#ifdef CONFIG_PM
static u32 wakeups[MAX_GPIO_BANKS];
static u32 backups[MAX_GPIO_BANKS];
static int gpio_irq_set_wake(struct irq_data *d, unsigned state)
{
struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
unsigned mask = 1 << d->hwirq;
unsigned bank = at91_gpio->pioc_idx;
if (unlikely(bank >= MAX_GPIO_BANKS))
return -EINVAL;
if (state)
wakeups[bank] |= mask;
else
wakeups[bank] &= ~mask;
irq_set_irq_wake(at91_gpio->pioc_virq, state);
return 0;
}
void at91_gpio_suspend(void)
{
int i;
for (i = 0; i < gpio_banks; i++) {
void __iomem *pio = gpio_chip[i].regbase;
backups[i] = __raw_readl(pio + PIO_IMR);
__raw_writel(backups[i], pio + PIO_IDR);
__raw_writel(wakeups[i], pio + PIO_IER);
if (!wakeups[i]) {
clk_unprepare(gpio_chip[i].clock);
clk_disable(gpio_chip[i].clock);
} else {
#ifdef CONFIG_PM_DEBUG
printk(KERN_DEBUG "GPIO-%c may wake for %08x\n", 'A'+i, wakeups[i]);
#endif
}
}
}
void at91_gpio_resume(void)
{
int i;
for (i = 0; i < gpio_banks; i++) {
void __iomem *pio = gpio_chip[i].regbase;
if (!wakeups[i]) {
if (clk_prepare(gpio_chip[i].clock) == 0)
clk_enable(gpio_chip[i].clock);
}
__raw_writel(wakeups[i], pio + PIO_IDR);
__raw_writel(backups[i], pio + PIO_IER);
}
}
#else
#define gpio_irq_set_wake NULL
#endif
/* Several AIC controller irqs are dispatched through this GPIO handler.
* To use any AT91_PIN_* as an externally triggered IRQ, first call
* at91_set_gpio_input() then maybe enable its glitch filter.
* Then just request_irq() with the pin ID; it works like any ARM IRQ
* handler.
* First implementation always triggers on rising and falling edges
* whereas the newer PIO3 can be additionally configured to trigger on
* level, edge with any polarity.
*
* Alternatively, certain pins may be used directly as IRQ0..IRQ6 after
* configuring them with at91_set_a_periph() or at91_set_b_periph().
* IRQ0..IRQ6 should be configurable, e.g. level vs edge triggering.
*/
static void gpio_irq_mask(struct irq_data *d)
{
struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
void __iomem *pio = at91_gpio->regbase;
unsigned mask = 1 << d->hwirq;
if (pio)
__raw_writel(mask, pio + PIO_IDR);
}
static void gpio_irq_unmask(struct irq_data *d)
{
struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
void __iomem *pio = at91_gpio->regbase;
unsigned mask = 1 << d->hwirq;
if (pio)
__raw_writel(mask, pio + PIO_IER);
}
static int gpio_irq_type(struct irq_data *d, unsigned type)
{
switch (type) {
case IRQ_TYPE_NONE:
case IRQ_TYPE_EDGE_BOTH:
return 0;
default:
return -EINVAL;
}
}
/* Alternate irq type for PIO3 support */
static int alt_gpio_irq_type(struct irq_data *d, unsigned type)
{
struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
void __iomem *pio = at91_gpio->regbase;
unsigned mask = 1 << d->hwirq;
switch (type) {
case IRQ_TYPE_EDGE_RISING:
__raw_writel(mask, pio + PIO_ESR);
__raw_writel(mask, pio + PIO_REHLSR);
break;
case IRQ_TYPE_EDGE_FALLING:
__raw_writel(mask, pio + PIO_ESR);
__raw_writel(mask, pio + PIO_FELLSR);
break;
case IRQ_TYPE_LEVEL_LOW:
__raw_writel(mask, pio + PIO_LSR);
__raw_writel(mask, pio + PIO_FELLSR);
break;
case IRQ_TYPE_LEVEL_HIGH:
__raw_writel(mask, pio + PIO_LSR);
__raw_writel(mask, pio + PIO_REHLSR);
break;
case IRQ_TYPE_EDGE_BOTH:
/*
* disable additional interrupt modes:
* fall back to default behavior
*/
__raw_writel(mask, pio + PIO_AIMDR);
return 0;
case IRQ_TYPE_NONE:
default:
pr_warn("AT91: No type for irq %d\n", gpio_to_irq(d->irq));
return -EINVAL;
}
/* enable additional interrupt modes */
__raw_writel(mask, pio + PIO_AIMER);
return 0;
}
static struct irq_chip gpio_irqchip = {
.name = "GPIO",
.irq_disable = gpio_irq_mask,
.irq_mask = gpio_irq_mask,
.irq_unmask = gpio_irq_unmask,
/* .irq_set_type is set dynamically */
.irq_set_wake = gpio_irq_set_wake,
};
static void gpio_irq_handler(unsigned irq, struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
struct irq_data *idata = irq_desc_get_irq_data(desc);
struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(idata);
void __iomem *pio = at91_gpio->regbase;
unsigned long isr;
int n;
chained_irq_enter(chip, desc);
for (;;) {
/* Reading ISR acks pending (edge triggered) GPIO interrupts.
* When there none are pending, we're finished unless we need
* to process multiple banks (like ID_PIOCDE on sam9263).
*/
isr = __raw_readl(pio + PIO_ISR) & __raw_readl(pio + PIO_IMR);
if (!isr) {
if (!at91_gpio->next)
break;
at91_gpio = at91_gpio->next;
pio = at91_gpio->regbase;
continue;
}
n = find_first_bit(&isr, BITS_PER_LONG);
while (n < BITS_PER_LONG) {
generic_handle_irq(irq_find_mapping(at91_gpio->domain, n));
n = find_next_bit(&isr, BITS_PER_LONG, n + 1);
}
}
chained_irq_exit(chip, desc);
/* now it may re-trigger */
}
/*--------------------------------------------------------------------------*/
#ifdef CONFIG_DEBUG_FS
static void gpio_printf(struct seq_file *s, void __iomem *pio, unsigned mask)
{
char *trigger = NULL;
char *polarity = NULL;
if (__raw_readl(pio + PIO_IMR) & mask) {
if (!has_pio3() || !(__raw_readl(pio + PIO_AIMMR) & mask )) {
trigger = "edge";
polarity = "both";
} else {
if (__raw_readl(pio + PIO_ELSR) & mask) {
trigger = "level";
polarity = __raw_readl(pio + PIO_FRLHSR) & mask ?
"high" : "low";
} else {
trigger = "edge";
polarity = __raw_readl(pio + PIO_FRLHSR) & mask ?
"rising" : "falling";
}
}
seq_printf(s, "IRQ:%s-%s\t", trigger, polarity);
} else {
seq_printf(s, "GPIO:%s\t\t",
__raw_readl(pio + PIO_PDSR) & mask ? "1" : "0");
}
}
static int at91_gpio_show(struct seq_file *s, void *unused)
{
int bank, j;
/* print heading */
seq_printf(s, "Pin\t");
for (bank = 0; bank < gpio_banks; bank++) {
seq_printf(s, "PIO%c\t\t", 'A' + bank);
};
seq_printf(s, "\n\n");
/* print pin status */
for (j = 0; j < 32; j++) {
seq_printf(s, "%i:\t", j);
for (bank = 0; bank < gpio_banks; bank++) {
unsigned pin = (32 * bank) + j;
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
if (__raw_readl(pio + PIO_PSR) & mask)
gpio_printf(s, pio, mask);
else
seq_printf(s, "%c\t\t",
peripheral_function(pio, mask));
}
seq_printf(s, "\n");
}
return 0;
}
static int at91_gpio_open(struct inode *inode, struct file *file)
{
return single_open(file, at91_gpio_show, NULL);
}
static const struct file_operations at91_gpio_operations = {
.open = at91_gpio_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int __init at91_gpio_debugfs_init(void)
{
/* /sys/kernel/debug/at91_gpio */
(void) debugfs_create_file("at91_gpio", S_IFREG | S_IRUGO, NULL, NULL, &at91_gpio_operations);
return 0;
}
postcore_initcall(at91_gpio_debugfs_init);
#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;
/*
* irqdomain initialization: pile up irqdomains on top of AIC range
*/
static void __init at91_gpio_irqdomain(struct at91_gpio_chip *at91_gpio)
{
int irq_base;
irq_base = irq_alloc_descs(-1, 0, at91_gpio->chip.ngpio, 0);
if (irq_base < 0)
panic("at91_gpio.%d: error %d: couldn't allocate IRQ numbers.\n",
at91_gpio->pioc_idx, irq_base);
at91_gpio->domain = irq_domain_add_legacy(NULL, at91_gpio->chip.ngpio,
irq_base, 0,
&irq_domain_simple_ops, NULL);
if (!at91_gpio->domain)
panic("at91_gpio.%d: couldn't allocate irq domain.\n",
at91_gpio->pioc_idx);
}
/*
* Called from the processor-specific init to enable GPIO interrupt support.
*/
void __init at91_gpio_irq_setup(void)
{
unsigned pioc;
int gpio_irqnbr = 0;
struct at91_gpio_chip *this, *prev;
/* Setup proper .irq_set_type function */
if (has_pio3())
gpio_irqchip.irq_set_type = alt_gpio_irq_type;
else
gpio_irqchip.irq_set_type = gpio_irq_type;
for (pioc = 0, this = gpio_chip, prev = NULL;
pioc++ < gpio_banks;
prev = this, this++) {
int offset;
__raw_writel(~0, this->regbase + PIO_IDR);
/* setup irq domain for this GPIO controller */
at91_gpio_irqdomain(this);
for (offset = 0; offset < this->chip.ngpio; offset++) {
unsigned int virq = irq_find_mapping(this->domain, offset);
irq_set_lockdep_class(virq, &gpio_lock_class);
/*
* Can use the "simple" and not "edge" handler since it's
* shorter, and the AIC handles interrupts sanely.
*/
irq_set_chip_and_handler(virq, &gpio_irqchip,
handle_simple_irq);
set_irq_flags(virq, IRQF_VALID);
irq_set_chip_data(virq, this);
gpio_irqnbr++;
}
/* The toplevel handler handles one bank of GPIOs, except
* on some SoC it can handles up to three...
* We only set up the handler for the first of the list.
*/
if (prev && prev->next == this)
continue;
this->pioc_virq = irq_create_mapping(NULL, this->pioc_hwirq);
irq_set_chip_data(this->pioc_virq, this);
irq_set_chained_handler(this->pioc_virq, gpio_irq_handler);
}
pr_info("AT91: %d gpio irqs in %d banks\n", gpio_irqnbr, gpio_banks);
}
/* gpiolib support */
static int at91_gpiolib_request(struct gpio_chip *chip, unsigned offset)
{
struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
void __iomem *pio = at91_gpio->regbase;
unsigned mask = 1 << offset;
__raw_writel(mask, pio + PIO_PER);
return 0;
}
static int at91_gpiolib_direction_input(struct gpio_chip *chip,
unsigned offset)
{
struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
void __iomem *pio = at91_gpio->regbase;
unsigned mask = 1 << offset;
__raw_writel(mask, pio + PIO_ODR);
return 0;
}
static int at91_gpiolib_direction_output(struct gpio_chip *chip,
unsigned offset, int val)
{
struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
void __iomem *pio = at91_gpio->regbase;
unsigned mask = 1 << offset;
__raw_writel(mask, pio + (val ? PIO_SODR : PIO_CODR));
__raw_writel(mask, pio + PIO_OER);
return 0;
}
static int at91_gpiolib_get(struct gpio_chip *chip, unsigned offset)
{
struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
void __iomem *pio = at91_gpio->regbase;
unsigned mask = 1 << offset;
u32 pdsr;
pdsr = __raw_readl(pio + PIO_PDSR);
return (pdsr & mask) != 0;
}
static void at91_gpiolib_set(struct gpio_chip *chip, unsigned offset, int val)
{
struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
void __iomem *pio = at91_gpio->regbase;
unsigned mask = 1 << offset;
__raw_writel(mask, pio + (val ? PIO_SODR : PIO_CODR));
}
static void at91_gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
int i;
for (i = 0; i < chip->ngpio; i++) {
unsigned pin = chip->base + i;
void __iomem *pio = pin_to_controller(pin);
unsigned mask = pin_to_mask(pin);
const char *gpio_label;
gpio_label = gpiochip_is_requested(chip, i);
if (gpio_label) {
seq_printf(s, "[%s] GPIO%s%d: ",
gpio_label, chip->label, i);
if (__raw_readl(pio + PIO_PSR) & mask)
seq_printf(s, "[gpio] %s\n",
at91_get_gpio_value(pin) ?
"set" : "clear");
else
seq_printf(s, "[periph %c]\n",
peripheral_function(pio, mask));
}
}
}
static int at91_gpiolib_to_irq(struct gpio_chip *chip, unsigned offset)
{
struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
int virq;
if (offset < chip->ngpio)
virq = irq_create_mapping(at91_gpio->domain, offset);
else
virq = -ENXIO;
dev_dbg(chip->dev, "%s: request IRQ for GPIO %d, return %d\n",
chip->label, offset + chip->base, virq);
return virq;
}
static int __init at91_gpio_setup_clk(int idx)
{
struct at91_gpio_chip *at91_gpio = &gpio_chip[idx];
/* retreive PIO controller's clock */
at91_gpio->clock = clk_get_sys(NULL, at91_gpio->chip.label);
if (IS_ERR(at91_gpio->clock)) {
pr_err("at91_gpio.%d, failed to get clock, ignoring.\n", idx);
goto err;
}
if (clk_prepare(at91_gpio->clock))
goto clk_prep_err;
/* enable PIO controller's clock */
if (clk_enable(at91_gpio->clock)) {
pr_err("at91_gpio.%d, failed to enable clock, ignoring.\n", idx);
goto clk_err;
}
return 0;
clk_err:
clk_unprepare(at91_gpio->clock);
clk_prep_err:
clk_put(at91_gpio->clock);
err:
return -EINVAL;
}
static void __init at91_gpio_init_one(int idx, u32 regbase, int pioc_hwirq)
{
struct at91_gpio_chip *at91_gpio = &gpio_chip[idx];
at91_gpio->chip.base = idx * MAX_NB_GPIO_PER_BANK;
at91_gpio->pioc_hwirq = pioc_hwirq;
at91_gpio->pioc_idx = idx;
at91_gpio->regbase = ioremap(regbase, 512);
if (!at91_gpio->regbase) {
pr_err("at91_gpio.%d, failed to map registers, ignoring.\n", idx);
return;
}
if (at91_gpio_setup_clk(idx))
goto ioremap_err;
gpio_banks = max(gpio_banks, idx + 1);
return;
ioremap_err:
iounmap(at91_gpio->regbase);
}
/*
* Called from the processor-specific init to enable GPIO pin support.
*/
void __init at91_gpio_init(struct at91_gpio_bank *data, int nr_banks)
{
unsigned i;
struct at91_gpio_chip *at91_gpio, *last = NULL;
BUG_ON(nr_banks > MAX_GPIO_BANKS);
if (of_have_populated_dt())
return;
for (i = 0; i < nr_banks; i++)
at91_gpio_init_one(i, data[i].regbase, data[i].id);
for (i = 0; i < gpio_banks; i++) {
at91_gpio = &gpio_chip[i];
/*
* GPIO controller are grouped on some SoC:
* PIOC, PIOD and PIOE can share the same IRQ line
*/
if (last && last->pioc_hwirq == at91_gpio->pioc_hwirq)
last->next = at91_gpio;
last = at91_gpio;
gpiochip_add(&at91_gpio->chip);
}
}