USB: core: remove polling for /sys/kernel/debug/usb/devices

#include <linux/fs.h>

#include <linux/mm.h>

#include <linux/gfp.h>

#include <linux/poll.h>

#include <linux/usb.h>

#include <linux/usbdevice_fs.h>

#include <linux/usb/hcd.h>

/* E:  Ad=xx(s) Atr=xx(ssss) MxPS=dddd Ivl=D?s */

  "E:  Ad=%02x(%c) Atr=%02x(%-4s) MxPS=%4d Ivl=%d%cs\n";

/*

 * Wait for an connect/disconnect event to happen. We initialize

 * the event counter with an odd number, and each event will increment

 * the event counter by two, so it will always _stay_ odd. That means

 * that it will never be zero, so "event 0" will never match a current

 * event, and thus 'poll' will always trigger as readable for the first

 * time it gets called.

 */

static struct device_connect_event {

	atomic_t count;

	wait_queue_head_t wait;

} device_event = {

	.count = ATOMIC_INIT(1),

	.wait = __WAIT_QUEUE_HEAD_INITIALIZER(device_event.wait)

};

struct class_info {

	int class;

	char *class_name;

/*****************************************************************/

void usbfs_conn_disc_event(void)

{

	atomic_add(2, &device_event.count);

	wake_up(&device_event.wait);

}

static const char *class_decode(const int class)

{

	int ix;

	return total_written;

}

/* Kernel lock for "lastev" protection */

static __poll_t usb_device_poll(struct file *file,

				    struct poll_table_struct *wait)

{

	unsigned int event_count;

	poll_wait(file, &device_event.wait, wait);

	event_count = atomic_read(&device_event.count);

	if (file->f_version != event_count) {

		file->f_version = event_count;

		return EPOLLIN | EPOLLRDNORM;

	}

	return 0;

}

const struct file_operations usbfs_devices_fops = {

	.llseek =	no_seek_end_llseek,

	.read =		usb_device_read,

	.poll =		usb_device_poll,

};

extern struct usb_driver usbfs_driver;

extern const struct file_operations usbfs_devices_fops;

extern const struct file_operations usbdev_file_operations;

extern void usbfs_conn_disc_event(void);

extern int usb_devio_init(void);

extern void usb_devio_cleanup(void);