diff options
Diffstat (limited to 'packages/linux/linux-2.6.18/gpio-dev-blocking-read.patch')
| -rw-r--r-- | packages/linux/linux-2.6.18/gpio-dev-blocking-read.patch | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/packages/linux/linux-2.6.18/gpio-dev-blocking-read.patch b/packages/linux/linux-2.6.18/gpio-dev-blocking-read.patch new file mode 100644 index 0000000000..9508d9e3aa --- /dev/null +++ b/packages/linux/linux-2.6.18/gpio-dev-blocking-read.patch @@ -0,0 +1,187 @@ +--- + 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; + } |