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---
arch/avr32/mach-at32ap/pio.c | 113 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 113 insertions(+)
Index: linux-2.6.18-avr32/arch/avr32/mach-at32ap/pio.c
===================================================================
--- linux-2.6.18-avr32.orig/arch/avr32/mach-at32ap/pio.c 2006-11-30 13:16:43.000000000 +0100
+++ linux-2.6.18-avr32/arch/avr32/mach-at32ap/pio.c 2006-11-30 17:15:24.000000000 +0100
@@ -250,7 +250,11 @@ EXPORT_SYMBOL(gpio_set_value);
#ifdef CONFIG_PIO_DEV
#include <linux/configfs.h>
#include <linux/cdev.h>
+#include <linux/fs.h>
+#include <linux/interrupt.h>
+#include <linux/poll.h>
#include <linux/uaccess.h>
+#include <linux/wait.h>
#define GPIO_DEV_MAX 8
@@ -267,6 +271,13 @@ struct gpio_item {
u32 pin_mask;
u32 oe_mask;
+ /* Pin state last time we read it (for blocking reads) */
+ u32 pin_state;
+ int changed;
+
+ wait_queue_head_t change_wq;
+ struct fasync_struct *async_queue;
+
int id;
struct class_device *gpio_dev;
struct cdev char_dev;
@@ -279,36 +290,135 @@ struct gpio_attribute {
ssize_t (*store)(struct gpio_item *, const char *, size_t);
};
+static irqreturn_t gpio_dev_interrupt(int irq, void *dev_id,
+ struct pt_regs *regs)
+{
+ struct gpio_item *gpio = dev_id;
+ u32 old_state, new_state;
+
+ old_state = gpio->pin_state;
+ new_state = pio_readl(gpio->pio, PDSR);
+ gpio->pin_state = new_state;
+
+ if (new_state != old_state) {
+ gpio->changed = 1;
+ wake_up_interruptible(&gpio->change_wq);
+
+ if (gpio->async_queue)
+ kill_fasync(&gpio->async_queue, SIGIO, POLL_IN);
+ }
+
+ return IRQ_HANDLED;
+}
+
static int gpio_dev_open(struct inode *inode, struct file *file)
{
struct gpio_item *gpio = container_of(inode->i_cdev,
struct gpio_item,
char_dev);
+ unsigned int irq;
+ unsigned int i;
+ int ret;
+ nonseekable_open(inode, file);
config_item_get(&gpio->item);
file->private_data = gpio;
+
+ gpio->pin_state = pio_readl(gpio->pio, PDSR) & gpio->pin_mask;
+ gpio->changed = 1;
+
+ for (i = 0; i < 32; i++) {
+ if (gpio->pin_mask & (1 << i)) {
+ irq = gpio_to_irq(32 * pio_id(gpio->pio) + i);
+ ret = request_irq(irq, gpio_dev_interrupt, 0,
+ "gpio-dev", gpio);
+ if (ret)
+ goto err_irq;
+ }
+ }
+
return 0;
+
+err_irq:
+ while (i--) {
+ if (gpio->pin_mask & (1 << i)) {
+ irq = gpio_to_irq(32 * pio_id(gpio->pio) + i);
+ free_irq(irq, gpio);
+ }
+ }
+
+ config_item_put(&gpio->item);
+
+ return ret;
+}
+
+static int gpio_dev_fasync(int fd, struct file *file, int mode)
+{
+ struct gpio_item *gpio = file->private_data;
+
+ return fasync_helper(fd, file, mode, &gpio->async_queue);
}
static int gpio_dev_release(struct inode *inode, struct file *file)
{
struct gpio_item *gpio = file->private_data;
+ unsigned int irq;
+ unsigned int i;
+
+ gpio_dev_fasync(-1, file, 0);
+
+ for (i = 0; i < 32; i++) {
+ if (gpio->pin_mask & (1 << i)) {
+ irq = gpio_to_irq(32 * pio_id(gpio->pio) + i);
+ free_irq(irq, gpio);
+ }
+ }
config_item_put(&gpio->item);
+
return 0;
}
+static unsigned int gpio_dev_poll(struct file *file, poll_table *wait)
+{
+ struct gpio_item *gpio = file->private_data;
+ unsigned int mask = 0;
+
+ poll_wait(file, &gpio->change_wq, wait);
+ if (gpio->changed)
+ mask |= POLLIN | POLLRDNORM;
+
+ return mask;
+}
+
static ssize_t gpio_dev_read(struct file *file, char __user *buf,
size_t count, loff_t *offset)
{
struct gpio_item *gpio = file->private_data;
u32 value;
+ spin_lock_irq(&gpio->lock);
+ while (!gpio->changed) {
+ spin_unlock_irq(&gpio->lock);
+
+ if (file->f_flags & O_NONBLOCK)
+ return -EAGAIN;
+
+ if (wait_event_interruptible(gpio->change_wq, gpio->changed))
+ return -ERESTARTSYS;
+
+ spin_lock_irq(&gpio->lock);
+ }
+
+ gpio->changed = 0;
value = pio_readl(gpio->pio, PDSR) & gpio->pin_mask;
+ spin_unlock_irq(&gpio->lock);
+
count = min(count, (size_t)4);
if (copy_to_user(buf, &value, count))
return -EFAULT;
+
return count;
}
@@ -338,6 +448,8 @@ static struct file_operations gpio_dev_f
.llseek = no_llseek,
.open = gpio_dev_open,
.release = gpio_dev_release,
+ .fasync = gpio_dev_fasync,
+ .poll = gpio_dev_poll,
.read = gpio_dev_read,
.write = gpio_dev_write,
};
@@ -632,6 +744,7 @@ static struct config_item *gpio_make_ite
gpio->id = next_id++;
config_item_init_type_name(&gpio->item, name, &gpio_item_type);
spin_lock_init(&gpio->lock);
+ init_waitqueue_head(&gpio->change_wq);
return &gpio->item;
}
|
