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linux/arch/arm/mach-orion/gpio.c

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/*
* arch/arm/mach-orion/gpio.c
*
* GPIO functions for Marvell Orion System On Chip
*
* Maintainer: Tzachi Perelstein <tzachi@marvell.com>
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/bitops.h>
#include <asm/gpio.h>
#include <asm/arch/orion.h>
#include "common.h"
static DEFINE_SPINLOCK(gpio_lock);
static unsigned long gpio_valid[BITS_TO_LONGS(GPIO_MAX)];
static const char *gpio_label[GPIO_MAX]; /* non null for allocated GPIOs */
void __init orion_gpio_set_valid_pins(u32 pins)
{
gpio_valid[0] = pins;
}
/*
* GENERIC_GPIO primitives
*/
int gpio_direction_input(unsigned pin)
{
unsigned long flags;
if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) {
pr_debug("%s: invalid GPIO %d\n", __FUNCTION__, pin);
return -EINVAL;
}
spin_lock_irqsave(&gpio_lock, flags);
/*
* Some callers might have not used the gpio_request(),
* so flag this pin as requested now.
*/
if (!gpio_label[pin])
gpio_label[pin] = "?";
orion_setbits(GPIO_IO_CONF, 1 << pin);
spin_unlock_irqrestore(&gpio_lock, flags);
return 0;
}
EXPORT_SYMBOL(gpio_direction_input);
int gpio_direction_output(unsigned pin, int value)
{
unsigned long flags;
int mask;
if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) {
pr_debug("%s: invalid GPIO %d\n", __FUNCTION__, pin);
return -EINVAL;
}
spin_lock_irqsave(&gpio_lock, flags);
/*
* Some callers might have not used the gpio_request(),
* so flag this pin as requested now.
*/
if (!gpio_label[pin])
gpio_label[pin] = "?";
mask = 1 << pin;
orion_clrbits(GPIO_BLINK_EN, mask);
if (value)
orion_setbits(GPIO_OUT, mask);
else
orion_clrbits(GPIO_OUT, mask);
orion_clrbits(GPIO_IO_CONF, mask);
spin_unlock_irqrestore(&gpio_lock, flags);
return 0;
}
EXPORT_SYMBOL(gpio_direction_output);
int gpio_get_value(unsigned pin)
{
int val, mask = 1 << pin;
if (orion_read(GPIO_IO_CONF) & mask)
val = orion_read(GPIO_DATA_IN) ^ orion_read(GPIO_IN_POL);
else
val = orion_read(GPIO_OUT);
return val & mask;
}
EXPORT_SYMBOL(gpio_get_value);
void gpio_set_value(unsigned pin, int value)
{
unsigned long flags;
int mask = 1 << pin;
spin_lock_irqsave(&gpio_lock, flags);
orion_clrbits(GPIO_BLINK_EN, mask);
if (value)
orion_setbits(GPIO_OUT, mask);
else
orion_clrbits(GPIO_OUT, mask);
spin_unlock_irqrestore(&gpio_lock, flags);
}
EXPORT_SYMBOL(gpio_set_value);
void orion_gpio_set_blink(unsigned pin, int blink)
{
unsigned long flags;
int mask = 1 << pin;
spin_lock_irqsave(&gpio_lock, flags);
orion_clrbits(GPIO_OUT, mask);
if (blink)
orion_setbits(GPIO_BLINK_EN, mask);
else
orion_clrbits(GPIO_BLINK_EN, mask);
spin_unlock_irqrestore(&gpio_lock, flags);
}
EXPORT_SYMBOL(orion_gpio_set_blink);
int gpio_request(unsigned pin, const char *label)
{
int ret = 0;
unsigned long flags;
if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) {
pr_debug("%s: invalid GPIO %d\n", __FUNCTION__, pin);
return -EINVAL;
}
spin_lock_irqsave(&gpio_lock, flags);
if (gpio_label[pin]) {
pr_debug("%s: GPIO %d already used as %s\n",
__FUNCTION__, pin, gpio_label[pin]);
ret = -EBUSY;
} else
gpio_label[pin] = label ? label : "?";
spin_unlock_irqrestore(&gpio_lock, flags);
return ret;
}
EXPORT_SYMBOL(gpio_request);
void gpio_free(unsigned pin)
{
if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) {
pr_debug("%s: invalid GPIO %d\n", __FUNCTION__, pin);
return;
}
if (!gpio_label[pin])
pr_warning("%s: GPIO %d already freed\n", __FUNCTION__, pin);
else
gpio_label[pin] = NULL;
}
EXPORT_SYMBOL(gpio_free);
/* Debug helper */
void gpio_display(void)
{
int i;
for (i = 0; i < GPIO_MAX; i++) {
printk(KERN_DEBUG "Pin-%d: ", i);
if (!test_bit(i, gpio_valid)) {
printk("non-GPIO\n");
} else if (!gpio_label[i]) {
printk("GPIO, free\n");
} else {
printk("GPIO, used by %s, ", gpio_label[i]);
if (orion_read(GPIO_IO_CONF) & (1 << i)) {
printk("input, active %s, level %s, edge %s\n",
((orion_read(GPIO_IN_POL) >> i) & 1) ? "low" : "high",
((orion_read(GPIO_LEVEL_MASK) >> i) & 1) ? "enabled" : "masked",
((orion_read(GPIO_EDGE_MASK) >> i) & 1) ? "enabled" : "masked");
} else {
printk("output, val=%d\n", (orion_read(GPIO_OUT) >> i) & 1);
}
}
}
printk(KERN_DEBUG "MPP_0_7_CTRL (0x%08x) = 0x%08x\n",
MPP_0_7_CTRL, orion_read(MPP_0_7_CTRL));
printk(KERN_DEBUG "MPP_8_15_CTRL (0x%08x) = 0x%08x\n",
MPP_8_15_CTRL, orion_read(MPP_8_15_CTRL));
printk(KERN_DEBUG "MPP_16_19_CTRL (0x%08x) = 0x%08x\n",
MPP_16_19_CTRL, orion_read(MPP_16_19_CTRL));
printk(KERN_DEBUG "MPP_DEV_CTRL (0x%08x) = 0x%08x\n",
MPP_DEV_CTRL, orion_read(MPP_DEV_CTRL));
printk(KERN_DEBUG "GPIO_OUT (0x%08x) = 0x%08x\n",
GPIO_OUT, orion_read(GPIO_OUT));
printk(KERN_DEBUG "GPIO_IO_CONF (0x%08x) = 0x%08x\n",
GPIO_IO_CONF, orion_read(GPIO_IO_CONF));
printk(KERN_DEBUG "GPIO_BLINK_EN (0x%08x) = 0x%08x\n",
GPIO_BLINK_EN, orion_read(GPIO_BLINK_EN));
printk(KERN_DEBUG "GPIO_IN_POL (0x%08x) = 0x%08x\n",
GPIO_IN_POL, orion_read(GPIO_IN_POL));
printk(KERN_DEBUG "GPIO_DATA_IN (0x%08x) = 0x%08x\n",
GPIO_DATA_IN, orion_read(GPIO_DATA_IN));
printk(KERN_DEBUG "GPIO_LEVEL_MASK (0x%08x) = 0x%08x\n",
GPIO_LEVEL_MASK, orion_read(GPIO_LEVEL_MASK));
printk(KERN_DEBUG "GPIO_EDGE_CAUSE (0x%08x) = 0x%08x\n",
GPIO_EDGE_CAUSE, orion_read(GPIO_EDGE_CAUSE));
printk(KERN_DEBUG "GPIO_EDGE_MASK (0x%08x) = 0x%08x\n",
GPIO_EDGE_MASK, orion_read(GPIO_EDGE_MASK));
}