linux-sg2042/arch/arm/plat-orion/gpio.c

589 lines
14 KiB
C

/*
* arch/arm/plat-orion/gpio.c
*
* Marvell Orion SoC GPIO handling.
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#define DEBUG
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/bitops.h>
#include <linux/io.h>
#include <linux/gpio.h>
#include <linux/leds.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/of_address.h>
#include <plat/orion-gpio.h>
/*
* GPIO unit register offsets.
*/
#define GPIO_OUT_OFF 0x0000
#define GPIO_IO_CONF_OFF 0x0004
#define GPIO_BLINK_EN_OFF 0x0008
#define GPIO_IN_POL_OFF 0x000c
#define GPIO_DATA_IN_OFF 0x0010
#define GPIO_EDGE_CAUSE_OFF 0x0014
#define GPIO_EDGE_MASK_OFF 0x0018
#define GPIO_LEVEL_MASK_OFF 0x001c
struct orion_gpio_chip {
struct gpio_chip chip;
spinlock_t lock;
void __iomem *base;
unsigned long valid_input;
unsigned long valid_output;
int mask_offset;
int secondary_irq_base;
struct irq_domain *domain;
};
static void __iomem *GPIO_OUT(struct orion_gpio_chip *ochip)
{
return ochip->base + GPIO_OUT_OFF;
}
static void __iomem *GPIO_IO_CONF(struct orion_gpio_chip *ochip)
{
return ochip->base + GPIO_IO_CONF_OFF;
}
static void __iomem *GPIO_BLINK_EN(struct orion_gpio_chip *ochip)
{
return ochip->base + GPIO_BLINK_EN_OFF;
}
static void __iomem *GPIO_IN_POL(struct orion_gpio_chip *ochip)
{
return ochip->base + GPIO_IN_POL_OFF;
}
static void __iomem *GPIO_DATA_IN(struct orion_gpio_chip *ochip)
{
return ochip->base + GPIO_DATA_IN_OFF;
}
static void __iomem *GPIO_EDGE_CAUSE(struct orion_gpio_chip *ochip)
{
return ochip->base + GPIO_EDGE_CAUSE_OFF;
}
static void __iomem *GPIO_EDGE_MASK(struct orion_gpio_chip *ochip)
{
return ochip->base + ochip->mask_offset + GPIO_EDGE_MASK_OFF;
}
static void __iomem *GPIO_LEVEL_MASK(struct orion_gpio_chip *ochip)
{
return ochip->base + ochip->mask_offset + GPIO_LEVEL_MASK_OFF;
}
static struct orion_gpio_chip orion_gpio_chips[2];
static int orion_gpio_chip_count;
static inline void
__set_direction(struct orion_gpio_chip *ochip, unsigned pin, int input)
{
u32 u;
u = readl(GPIO_IO_CONF(ochip));
if (input)
u |= 1 << pin;
else
u &= ~(1 << pin);
writel(u, GPIO_IO_CONF(ochip));
}
static void __set_level(struct orion_gpio_chip *ochip, unsigned pin, int high)
{
u32 u;
u = readl(GPIO_OUT(ochip));
if (high)
u |= 1 << pin;
else
u &= ~(1 << pin);
writel(u, GPIO_OUT(ochip));
}
static inline void
__set_blinking(struct orion_gpio_chip *ochip, unsigned pin, int blink)
{
u32 u;
u = readl(GPIO_BLINK_EN(ochip));
if (blink)
u |= 1 << pin;
else
u &= ~(1 << pin);
writel(u, GPIO_BLINK_EN(ochip));
}
static inline int
orion_gpio_is_valid(struct orion_gpio_chip *ochip, unsigned pin, int mode)
{
if (pin >= ochip->chip.ngpio)
goto err_out;
if ((mode & GPIO_INPUT_OK) && !test_bit(pin, &ochip->valid_input))
goto err_out;
if ((mode & GPIO_OUTPUT_OK) && !test_bit(pin, &ochip->valid_output))
goto err_out;
return 1;
err_out:
pr_debug("%s: invalid GPIO %d\n", __func__, pin);
return false;
}
/*
* GENERIC_GPIO primitives.
*/
static int orion_gpio_request(struct gpio_chip *chip, unsigned pin)
{
struct orion_gpio_chip *ochip =
container_of(chip, struct orion_gpio_chip, chip);
if (orion_gpio_is_valid(ochip, pin, GPIO_INPUT_OK) ||
orion_gpio_is_valid(ochip, pin, GPIO_OUTPUT_OK))
return 0;
return -EINVAL;
}
static int orion_gpio_direction_input(struct gpio_chip *chip, unsigned pin)
{
struct orion_gpio_chip *ochip =
container_of(chip, struct orion_gpio_chip, chip);
unsigned long flags;
if (!orion_gpio_is_valid(ochip, pin, GPIO_INPUT_OK))
return -EINVAL;
spin_lock_irqsave(&ochip->lock, flags);
__set_direction(ochip, pin, 1);
spin_unlock_irqrestore(&ochip->lock, flags);
return 0;
}
static int orion_gpio_get(struct gpio_chip *chip, unsigned pin)
{
struct orion_gpio_chip *ochip =
container_of(chip, struct orion_gpio_chip, chip);
int val;
if (readl(GPIO_IO_CONF(ochip)) & (1 << pin)) {
val = readl(GPIO_DATA_IN(ochip)) ^ readl(GPIO_IN_POL(ochip));
} else {
val = readl(GPIO_OUT(ochip));
}
return (val >> pin) & 1;
}
static int
orion_gpio_direction_output(struct gpio_chip *chip, unsigned pin, int value)
{
struct orion_gpio_chip *ochip =
container_of(chip, struct orion_gpio_chip, chip);
unsigned long flags;
if (!orion_gpio_is_valid(ochip, pin, GPIO_OUTPUT_OK))
return -EINVAL;
spin_lock_irqsave(&ochip->lock, flags);
__set_blinking(ochip, pin, 0);
__set_level(ochip, pin, value);
__set_direction(ochip, pin, 0);
spin_unlock_irqrestore(&ochip->lock, flags);
return 0;
}
static void orion_gpio_set(struct gpio_chip *chip, unsigned pin, int value)
{
struct orion_gpio_chip *ochip =
container_of(chip, struct orion_gpio_chip, chip);
unsigned long flags;
spin_lock_irqsave(&ochip->lock, flags);
__set_level(ochip, pin, value);
spin_unlock_irqrestore(&ochip->lock, flags);
}
static int orion_gpio_to_irq(struct gpio_chip *chip, unsigned pin)
{
struct orion_gpio_chip *ochip =
container_of(chip, struct orion_gpio_chip, chip);
return irq_create_mapping(ochip->domain,
ochip->secondary_irq_base + pin);
}
/*
* Orion-specific GPIO API extensions.
*/
static struct orion_gpio_chip *orion_gpio_chip_find(int pin)
{
int i;
for (i = 0; i < orion_gpio_chip_count; i++) {
struct orion_gpio_chip *ochip = orion_gpio_chips + i;
struct gpio_chip *chip = &ochip->chip;
if (pin >= chip->base && pin < chip->base + chip->ngpio)
return ochip;
}
return NULL;
}
void __init orion_gpio_set_unused(unsigned pin)
{
struct orion_gpio_chip *ochip = orion_gpio_chip_find(pin);
if (ochip == NULL)
return;
pin -= ochip->chip.base;
/* Configure as output, drive low. */
__set_level(ochip, pin, 0);
__set_direction(ochip, pin, 0);
}
void __init orion_gpio_set_valid(unsigned pin, int mode)
{
struct orion_gpio_chip *ochip = orion_gpio_chip_find(pin);
if (ochip == NULL)
return;
pin -= ochip->chip.base;
if (mode == 1)
mode = GPIO_INPUT_OK | GPIO_OUTPUT_OK;
if (mode & GPIO_INPUT_OK)
__set_bit(pin, &ochip->valid_input);
else
__clear_bit(pin, &ochip->valid_input);
if (mode & GPIO_OUTPUT_OK)
__set_bit(pin, &ochip->valid_output);
else
__clear_bit(pin, &ochip->valid_output);
}
void orion_gpio_set_blink(unsigned pin, int blink)
{
struct orion_gpio_chip *ochip = orion_gpio_chip_find(pin);
unsigned long flags;
if (ochip == NULL)
return;
spin_lock_irqsave(&ochip->lock, flags);
__set_level(ochip, pin & 31, 0);
__set_blinking(ochip, pin & 31, blink);
spin_unlock_irqrestore(&ochip->lock, flags);
}
EXPORT_SYMBOL(orion_gpio_set_blink);
#define ORION_BLINK_HALF_PERIOD 100 /* ms */
int orion_gpio_led_blink_set(unsigned gpio, int state,
unsigned long *delay_on, unsigned long *delay_off)
{
if (delay_on && delay_off && !*delay_on && !*delay_off)
*delay_on = *delay_off = ORION_BLINK_HALF_PERIOD;
switch (state) {
case GPIO_LED_NO_BLINK_LOW:
case GPIO_LED_NO_BLINK_HIGH:
orion_gpio_set_blink(gpio, 0);
gpio_set_value(gpio, state);
break;
case GPIO_LED_BLINK:
orion_gpio_set_blink(gpio, 1);
}
return 0;
}
EXPORT_SYMBOL_GPL(orion_gpio_led_blink_set);
/*****************************************************************************
* Orion GPIO IRQ
*
* GPIO_IN_POL register controls whether GPIO_DATA_IN will hold the same
* value of the line or the opposite value.
*
* Level IRQ handlers: DATA_IN is used directly as cause register.
* Interrupt are masked by LEVEL_MASK registers.
* Edge IRQ handlers: Change in DATA_IN are latched in EDGE_CAUSE.
* Interrupt are masked by EDGE_MASK registers.
* Both-edge handlers: Similar to regular Edge handlers, but also swaps
* the polarity to catch the next line transaction.
* This is a race condition that might not perfectly
* work on some use cases.
*
* Every eight GPIO lines are grouped (OR'ed) before going up to main
* cause register.
*
* EDGE cause mask
* data-in /--------| |-----| |----\
* -----| |----- ---- to main cause reg
* X \----------------| |----/
* polarity LEVEL mask
*
****************************************************************************/
static int gpio_irq_set_type(struct irq_data *d, u32 type)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct irq_chip_type *ct = irq_data_get_chip_type(d);
struct orion_gpio_chip *ochip = gc->private;
int pin;
u32 u;
pin = d->hwirq - ochip->secondary_irq_base;
u = readl(GPIO_IO_CONF(ochip)) & (1 << pin);
if (!u) {
return -EINVAL;
}
type &= IRQ_TYPE_SENSE_MASK;
if (type == IRQ_TYPE_NONE)
return -EINVAL;
/* Check if we need to change chip and handler */
if (!(ct->type & type))
if (irq_setup_alt_chip(d, type))
return -EINVAL;
/*
* Configure interrupt polarity.
*/
if (type == IRQ_TYPE_EDGE_RISING || type == IRQ_TYPE_LEVEL_HIGH) {
u = readl(GPIO_IN_POL(ochip));
u &= ~(1 << pin);
writel(u, GPIO_IN_POL(ochip));
} else if (type == IRQ_TYPE_EDGE_FALLING || type == IRQ_TYPE_LEVEL_LOW) {
u = readl(GPIO_IN_POL(ochip));
u |= 1 << pin;
writel(u, GPIO_IN_POL(ochip));
} else if (type == IRQ_TYPE_EDGE_BOTH) {
u32 v;
v = readl(GPIO_IN_POL(ochip)) ^ readl(GPIO_DATA_IN(ochip));
/*
* set initial polarity based on current input level
*/
u = readl(GPIO_IN_POL(ochip));
if (v & (1 << pin))
u |= 1 << pin; /* falling */
else
u &= ~(1 << pin); /* rising */
writel(u, GPIO_IN_POL(ochip));
}
return 0;
}
static void gpio_irq_handler(unsigned irq, struct irq_desc *desc)
{
struct orion_gpio_chip *ochip = irq_get_handler_data(irq);
u32 cause, type;
int i;
if (ochip == NULL)
return;
cause = readl(GPIO_DATA_IN(ochip)) & readl(GPIO_LEVEL_MASK(ochip));
cause |= readl(GPIO_EDGE_CAUSE(ochip)) & readl(GPIO_EDGE_MASK(ochip));
for (i = 0; i < ochip->chip.ngpio; i++) {
int irq;
irq = ochip->secondary_irq_base + i;
if (!(cause & (1 << i)))
continue;
type = irqd_get_trigger_type(irq_get_irq_data(irq));
if ((type & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH) {
/* Swap polarity (race with GPIO line) */
u32 polarity;
polarity = readl(GPIO_IN_POL(ochip));
polarity ^= 1 << i;
writel(polarity, GPIO_IN_POL(ochip));
}
generic_handle_irq(irq);
}
}
void __init orion_gpio_init(struct device_node *np,
int gpio_base, int ngpio,
void __iomem *base, int mask_offset,
int secondary_irq_base,
int irqs[4])
{
struct orion_gpio_chip *ochip;
struct irq_chip_generic *gc;
struct irq_chip_type *ct;
char gc_label[16];
int i;
if (orion_gpio_chip_count == ARRAY_SIZE(orion_gpio_chips))
return;
snprintf(gc_label, sizeof(gc_label), "orion_gpio%d",
orion_gpio_chip_count);
ochip = orion_gpio_chips + orion_gpio_chip_count;
ochip->chip.label = kstrdup(gc_label, GFP_KERNEL);
ochip->chip.request = orion_gpio_request;
ochip->chip.direction_input = orion_gpio_direction_input;
ochip->chip.get = orion_gpio_get;
ochip->chip.direction_output = orion_gpio_direction_output;
ochip->chip.set = orion_gpio_set;
ochip->chip.to_irq = orion_gpio_to_irq;
ochip->chip.base = gpio_base;
ochip->chip.ngpio = ngpio;
ochip->chip.can_sleep = 0;
#ifdef CONFIG_OF
ochip->chip.of_node = np;
#endif
spin_lock_init(&ochip->lock);
ochip->base = (void __iomem *)base;
ochip->valid_input = 0;
ochip->valid_output = 0;
ochip->mask_offset = mask_offset;
ochip->secondary_irq_base = secondary_irq_base;
gpiochip_add(&ochip->chip);
/*
* Mask and clear GPIO interrupts.
*/
writel(0, GPIO_EDGE_CAUSE(ochip));
writel(0, GPIO_EDGE_MASK(ochip));
writel(0, GPIO_LEVEL_MASK(ochip));
/* Setup the interrupt handlers. Each chip can have up to 4
* interrupt handlers, with each handler dealing with 8 GPIO
* pins. */
for (i = 0; i < 4; i++) {
if (irqs[i]) {
irq_set_handler_data(irqs[i], ochip);
irq_set_chained_handler(irqs[i], gpio_irq_handler);
}
}
gc = irq_alloc_generic_chip("orion_gpio_irq", 2,
secondary_irq_base,
ochip->base, handle_level_irq);
gc->private = ochip;
ct = gc->chip_types;
ct->regs.mask = ochip->mask_offset + GPIO_LEVEL_MASK_OFF;
ct->type = IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW;
ct->chip.irq_mask = irq_gc_mask_clr_bit;
ct->chip.irq_unmask = irq_gc_mask_set_bit;
ct->chip.irq_set_type = gpio_irq_set_type;
ct->chip.name = ochip->chip.label;
ct++;
ct->regs.mask = ochip->mask_offset + GPIO_EDGE_MASK_OFF;
ct->regs.ack = GPIO_EDGE_CAUSE_OFF;
ct->type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
ct->chip.irq_ack = irq_gc_ack_clr_bit;
ct->chip.irq_mask = irq_gc_mask_clr_bit;
ct->chip.irq_unmask = irq_gc_mask_set_bit;
ct->chip.irq_set_type = gpio_irq_set_type;
ct->handler = handle_edge_irq;
ct->chip.name = ochip->chip.label;
irq_setup_generic_chip(gc, IRQ_MSK(ngpio), IRQ_GC_INIT_MASK_CACHE,
IRQ_NOREQUEST, IRQ_LEVEL | IRQ_NOPROBE);
/* Setup irq domain on top of the generic chip. */
ochip->domain = irq_domain_add_legacy(np,
ochip->chip.ngpio,
ochip->secondary_irq_base,
ochip->secondary_irq_base,
&irq_domain_simple_ops,
ochip);
if (!ochip->domain)
panic("%s: couldn't allocate irq domain (DT).\n",
ochip->chip.label);
orion_gpio_chip_count++;
}
#ifdef CONFIG_OF
static void __init orion_gpio_of_init_one(struct device_node *np,
int irq_gpio_base)
{
int ngpio, gpio_base, mask_offset;
void __iomem *base;
int ret, i;
int irqs[4];
int secondary_irq_base;
ret = of_property_read_u32(np, "ngpio", &ngpio);
if (ret)
goto out;
ret = of_property_read_u32(np, "mask-offset", &mask_offset);
if (ret == -EINVAL)
mask_offset = 0;
else
goto out;
base = of_iomap(np, 0);
if (!base)
goto out;
secondary_irq_base = irq_gpio_base + (32 * orion_gpio_chip_count);
gpio_base = 32 * orion_gpio_chip_count;
/* Get the interrupt numbers. Each chip can have up to 4
* interrupt handlers, with each handler dealing with 8 GPIO
* pins. */
for (i = 0; i < 4; i++)
irqs[i] = irq_of_parse_and_map(np, i);
orion_gpio_init(np, gpio_base, ngpio, base, mask_offset,
secondary_irq_base, irqs);
return;
out:
pr_err("%s: %s: missing mandatory property\n", __func__, np->name);
}
void __init orion_gpio_of_init(int irq_gpio_base)
{
struct device_node *np;
for_each_compatible_node(np, NULL, "marvell,orion-gpio")
orion_gpio_of_init_one(np, irq_gpio_base);
}
#endif