/*
* Driver for NEC VR4100 series General-purpose I/O Unit.
*/
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/gpio.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include <asm/vr41xx/giu.h>
#include <asm/vr41xx/irq.h>
#include <asm/vr41xx/vr41xx.h>
MODULE_AUTHOR("Yoichi Yuasa <yuasa@linux-mips.org>");
MODULE_DESCRIPTION("NEC VR4100 series General-purpose I/O Unit driver");
MODULE_LICENSE("GPL");
#define GIUIOSELL 0x00
#define GIUIOSELH 0x02
#define GIUPIODL 0x04
#define GIUPIODH 0x06
#define GIUINTSTATL 0x08
#define GIUINTSTATH 0x0a
#define GIUINTENL 0x0c
#define GIUINTENH 0x0e
#define GIUINTTYPL 0x10
#define GIUINTTYPH 0x12
#define GIUINTALSELL 0x14
#define GIUINTALSELH 0x16
#define GIUINTHTSELL 0x18
#define GIUINTHTSELH 0x1a
#define GIUPODATL 0x1c
#define GIUPODATEN 0x1c
#define GIUPODATH 0x1e
#define PIOEN0 0x0100
#define PIOEN1 0x0200
#define GIUPODAT 0x1e
#define GIUFEDGEINHL 0x20
#define GIUFEDGEINHH 0x22
#define GIUREDGEINHL 0x24
#define GIUREDGEINHH 0x26
#define GIUUSEUPDN 0x1e0
#define GIUTERMUPDN 0x1e2
#define GPIO_HAS_PULLUPDOWN_IO 0x0001
#define GPIO_HAS_OUTPUT_ENABLE 0x0002
#define GPIO_HAS_INTERRUPT_EDGE_SELECT 0x0100
enum {
GPIO_INPUT,
GPIO_OUTPUT,
};
static DEFINE_SPINLOCK(giu_lock);
static unsigned long giu_flags;
static void __iomem *giu_base;
#define giu_read(offset) readw(giu_base + (offset))
#define giu_write(offset, value) writew((value), giu_base + (offset))
#define GPIO_PIN_OF_IRQ(irq) ((irq) - GIU_IRQ_BASE)
#define GIUINT_HIGH_OFFSET 16
#define GIUINT_HIGH_MAX 32
static inline u16 giu_set(u16 offset, u16 set)
{
u16 data;
data = giu_read(offset);
data |= set;
giu_write(offset, data);
return data;
}
static inline u16 giu_clear(u16 offset, u16 clear)
{
u16 data;
data = giu_read(offset);
data &= ~clear;
giu_write(offset, data);
return data;
}
static void ack_giuint_low(struct irq_data *d)
{
giu_write(GIUINTSTATL, 1 << GPIO_PIN_OF_IRQ(d->irq));
}
static void mask_giuint_low(struct irq_data *d)
{
giu_clear(GIUINTENL, 1 << GPIO_PIN_OF_IRQ(d->irq));
}
static void mask_ack_giuint_low(struct irq_data *d)
{
unsigned int pin;
pin = GPIO_PIN_OF_IRQ(d->irq);
giu_clear(GIUINTENL, 1 << pin);
giu_write(GIUINTSTATL, 1 << pin);
}
static void unmask_giuint_low(struct irq_data *d)
{
giu_set(GIUINTENL, 1 << GPIO_PIN_OF_IRQ(d->irq));
}
static struct irq_chip giuint_low_irq_chip = {
.name = "GIUINTL",
.irq_ack = ack_giuint_low,
.irq_mask = mask_giuint_low,
.irq_mask_ack = mask_ack_giuint_low,
.irq_unmask = unmask_giuint_low,
};
static void ack_giuint_high(struct irq_data *d)
{
giu_write(GIUINTSTATH,
1 << (GPIO_PIN_OF_IRQ(d->irq) - GIUINT_HIGH_OFFSET));
}
static void mask_giuint_high(struct irq_data *d)
{
giu_clear(GIUINTENH, 1 << (GPIO_PIN_OF_IRQ(d->irq) - GIUINT_HIGH_OFFSET));
}
static void mask_ack_giuint_high(struct irq_data *d)
{
unsigned int pin;
pin = GPIO_PIN_OF_IRQ(d->irq) - GIUINT_HIGH_OFFSET;
giu_clear(GIUINTENH, 1 << pin);
giu_write(GIUINTSTATH, 1 << pin);
}
static void unmask_giuint_high(struct irq_data *d)
{
giu_set(GIUINTENH, 1 << (GPIO_PIN_OF_IRQ(d->irq) - GIUINT_HIGH_OFFSET));
}
static struct irq_chip giuint_high_irq_chip = {
.name = "GIUINTH",
.irq_ack = ack_giuint_high,
.irq_mask = mask_giuint_high,
.irq_mask_ack = mask_ack_giuint_high,
.irq_unmask = unmask_giuint_high,
};
static int giu_get_irq(unsigned int irq)
{
u16 pendl, pendh, maskl, maskh;
int i;
pendl = giu_read(GIUINTSTATL);
pendh = giu_read(GIUINTSTATH);
maskl = giu_read(GIUINTENL);
maskh = giu_read(GIUINTENH);
maskl &= pendl;
maskh &= pendh;
if (maskl) {
for (i = 0; i < 16; i++) {
if (maskl & (1 << i))
return GIU_IRQ(i);
}
} else if (maskh) {
for (i = 0; i < 16; i++) {
if (maskh & (1 << i))
return GIU_IRQ(i + GIUINT_HIGH_OFFSET);
}
}
printk(KERN_ERR "spurious GIU interrupt: %04x(%04x),%04x(%04x)\n",
maskl, pendl, maskh, pendh);
atomic_inc(&irq_err_count);
return -EINVAL;
}
void vr41xx_set_irq_trigger(unsigned int pin, irq_trigger_t trigger,
irq_signal_t signal)
{
u16 mask;
if (pin < GIUINT_HIGH_OFFSET) {
mask = 1 << pin;
if (trigger != IRQ_TRIGGER_LEVEL) {
giu_set(GIUINTTYPL, mask);
if (signal == IRQ_SIGNAL_HOLD)
giu_set(GIUINTHTSELL, mask);
else
giu_clear(GIUINTHTSELL, mask);
if (giu_flags & GPIO_HAS_INTERRUPT_EDGE_SELECT) {
switch (trigger) {
case IRQ_TRIGGER_EDGE_FALLING:
giu_set(GIUFEDGEINHL, mask);
giu_clear(GIUREDGEINHL, mask);
break;
case IRQ_TRIGGER_EDGE_RISING:
giu_clear(GIUFEDGEINHL, mask);
giu_set(GIUREDGEINHL, mask);
break;
default:
giu_set(GIUFEDGEINHL, mask);
giu_set(GIUREDGEINHL, mask);
break;
}
}
irq_set_chip_and_handler(GIU_IRQ(pin),
&giuint_low_irq_chip,
handle_edge_irq);
} else {
giu_clear(GIUINTTYPL, mask);
giu_clear(GIUINTHTSELL, mask);
irq_set_chip_and_handler(GIU_IRQ(pin),
&giuint_low_irq_chip,
handle_level_irq);
}
giu_write(GIUINTSTATL, mask);
} else if (pin < GIUINT_HIGH_MAX) {
mask = 1 << (pin - GIUINT_HIGH_OFFSET);
if (trigger != IRQ_TRIGGER_LEVEL) {
giu_set(GIUINTTYPH, mask);
if (signal == IRQ_SIGNAL_HOLD)
giu_set(GIUINTHTSELH, mask);
else
giu_clear(GIUINTHTSELH, mask);
if (giu_flags & GPIO_HAS_INTERRUPT_EDGE_SELECT) {
switch (trigger) {
case IRQ_TRIGGER_EDGE_FALLING:
giu_set(GIUFEDGEINHH, mask);
giu_clear(GIUREDGEINHH, mask);
break;
case IRQ_TRIGGER_EDGE_RISING:
giu_clear(GIUFEDGEINHH, mask);
giu_set(GIUREDGEINHH, mask);
break;
default:
giu_set(GIUFEDGEINHH, mask);
giu_set(GIUREDGEINHH, mask);
break;
}
}
irq_set_chip_and_handler(GIU_IRQ(pin),
&giuint_high_irq_chip,
handle_edge_irq);
} else {
giu_clear(GIUINTTYPH, mask);
giu_clear(GIUINTHTSELH, mask);
irq_set_chip_and_handler(GIU_IRQ(pin),
&giuint_high_irq_chip,
handle_level_irq);
}
giu_write(GIUINTSTATH, mask);
}
}
EXPORT_SYMBOL_GPL(vr41xx_set_irq_trigger);
void vr41xx_set_irq_level(unsigned int pin, irq_level_t level)
{
u16 mask;
if (pin < GIUINT_HIGH_OFFSET) {
mask = 1 << pin;
if (level == IRQ_LEVEL_HIGH)
giu_set(GIUINTALSELL, mask);
else
giu_clear(GIUINTALSELL, mask);
giu_write(GIUINTSTATL, mask);
} else if (pin < GIUINT_HIGH_MAX) {
mask = 1 << (pin - GIUINT_HIGH_OFFSET);
if (level == IRQ_LEVEL_HIGH)
giu_set(GIUINTALSELH, mask);
else
giu_clear(GIUINTALSELH, mask);
giu_write(GIUINTSTATH, mask);
}
}
EXPORT_SYMBOL_GPL(vr41xx_set_irq_level);
static int giu_set_direction(struct gpio_chip *chip, unsigned pin, int dir)
{
u16 offset, mask, reg;
unsigned long flags;
if (pin >= chip->ngpio)
return -EINVAL;
if (pin < 16) {
offset = GIUIOSELL;
mask = 1 << pin;
} else if (pin < 32) {
offset = GIUIOSELH;
mask = 1 << (pin - 16);
} else {
if (giu_flags & GPIO_HAS_OUTPUT_ENABLE) {
offset = GIUPODATEN;
mask = 1 << (pin - 32);
} else {
switch (pin) {
case 48:
offset = GIUPODATH;
mask = PIOEN0;
break;
case 49:
offset = GIUPODATH;
mask = PIOEN1;
break;
default:
return -EINVAL;
}
}
}
spin_lock_irqsave(&giu_lock, flags);
reg = giu_read(offset);
if (dir == GPIO_OUTPUT)
reg |= mask;
else
reg &= ~mask;
giu_write(offset, reg);
spin_unlock_irqrestore(&giu_lock, flags);
return 0;
}
int vr41xx_gpio_pullupdown(unsigned int pin, gpio_pull_t pull)
{
u16 reg, mask;
unsigned long flags;
if ((giu_flags & GPIO_HAS_PULLUPDOWN_IO) != GPIO_HAS_PULLUPDOWN_IO)
return -EPERM;
if (pin >= 15)
return -EINVAL;
mask = 1 << pin;
spin_lock_irqsave(&giu_lock, flags);
if (pull == GPIO_PULL_UP || pull == GPIO_PULL_DOWN) {
reg = giu_read(GIUTERMUPDN);
if (pull == GPIO_PULL_UP)
