+++ /dev/null
-/*
- * LED USB device Trigger
- *
- * Toggles the LED to reflect the presence and activity of an USB device
- * Copyright (C) Gabor Juhos <juhosg@openwrt.org>
- *
- * derived from ledtrig-netdev.c:
- * Copyright 2007 Oliver Jowett <oliver@opencloud.com>
- *
- * ledtrig-netdev.c derived from ledtrig-timer.c:
- * Copyright 2005-2006 Openedhand Ltd.
- * Author: Richard Purdie <rpurdie@openedhand.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- */
-
-#include <linux/module.h>
-#include <linux/jiffies.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/list.h>
-#include <linux/spinlock.h>
-#include <linux/device.h>
-#include <linux/sysdev.h>
-#include <linux/timer.h>
-#include <linux/ctype.h>
-#include <linux/slab.h>
-#include <linux/leds.h>
-#include <linux/usb.h>
-
-#include "leds.h"
-
-#define DEV_BUS_ID_SIZE 32
-
-/*
- * Configurable sysfs attributes:
- *
- * device_name - name of the USB device to monitor
- * activity_interval - duration of LED blink, in milliseconds
- */
-
-struct usbdev_trig_data {
- rwlock_t lock;
-
- struct timer_list timer;
- struct notifier_block notifier;
-
- struct led_classdev *led_cdev;
- struct usb_device *usb_dev;
-
- char device_name[DEV_BUS_ID_SIZE];
- unsigned interval;
- int last_urbnum;
-};
-
-static void usbdev_trig_update_state(struct usbdev_trig_data *td)
-{
- if (td->usb_dev)
- led_set_brightness(td->led_cdev, LED_FULL);
- else
- led_set_brightness(td->led_cdev, LED_OFF);
-
- if (td->interval && td->usb_dev)
- mod_timer(&td->timer, jiffies + td->interval);
- else
- del_timer(&td->timer);
-}
-
-static ssize_t usbdev_trig_name_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct led_classdev *led_cdev = dev_get_drvdata(dev);
- struct usbdev_trig_data *td = led_cdev->trigger_data;
-
- read_lock(&td->lock);
- sprintf(buf, "%s\n", td->device_name);
- read_unlock(&td->lock);
-
- return strlen(buf) + 1;
-}
-
-struct usbdev_trig_match {
- char *device_name;
- struct usb_device *usb_dev;
-};
-
-static int usbdev_trig_find_usb_dev(struct usb_device *usb_dev, void *data)
-{
- struct usbdev_trig_match *match = data;
-
- if (strcmp(dev_name(&usb_dev->dev), match->device_name) != 0)
- return 0;
-
- if (WARN_ON(match->usb_dev))
- return 0;
-
- dev_dbg(&usb_dev->dev, "matched this device!\n");
- match->usb_dev = usb_get_dev(usb_dev);
-
- return 0;
-}
-
-static ssize_t usbdev_trig_name_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t size)
-{
- struct led_classdev *led_cdev = dev_get_drvdata(dev);
- struct usbdev_trig_data *td = led_cdev->trigger_data;
-
- if (size < 0 || size >= DEV_BUS_ID_SIZE)
- return -EINVAL;
-
- write_lock(&td->lock);
-
- strcpy(td->device_name, buf);
- if (size > 0 && td->device_name[size - 1] == '\n')
- td->device_name[size - 1] = 0;
-
- if (td->device_name[0] != 0) {
- struct usbdev_trig_match match = {
- .device_name = td->device_name,
- };
-
- /* check for existing device to update from */
- usb_for_each_dev(&match, usbdev_trig_find_usb_dev);
- if (match.usb_dev) {
- if (td->usb_dev)
- usb_put_dev(td->usb_dev);
-
- td->usb_dev = match.usb_dev;
- td->last_urbnum = atomic_read(&match.usb_dev->urbnum);
- }
-
- /* updates LEDs, may start timers */
- usbdev_trig_update_state(td);
- }
-
- write_unlock(&td->lock);
- return size;
-}
-
-static DEVICE_ATTR(device_name, 0644, usbdev_trig_name_show,
- usbdev_trig_name_store);
-
-static ssize_t usbdev_trig_interval_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct led_classdev *led_cdev = dev_get_drvdata(dev);
- struct usbdev_trig_data *td = led_cdev->trigger_data;
-
- read_lock(&td->lock);
- sprintf(buf, "%u\n", jiffies_to_msecs(td->interval));
- read_unlock(&td->lock);
-
- return strlen(buf) + 1;
-}
-
-static ssize_t usbdev_trig_interval_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t size)
-{
- struct led_classdev *led_cdev = dev_get_drvdata(dev);
- struct usbdev_trig_data *td = led_cdev->trigger_data;
- int ret = -EINVAL;
- char *after;
- unsigned long value = simple_strtoul(buf, &after, 10);
- size_t count = after - buf;
-
- if (*after && isspace(*after))
- count++;
-
- if (count == size && value <= 10000) {
- write_lock(&td->lock);
- td->interval = msecs_to_jiffies(value);
- usbdev_trig_update_state(td); /* resets timer */
- write_unlock(&td->lock);
- ret = count;
- }
-
- return ret;
-}
-
-static DEVICE_ATTR(activity_interval, 0644, usbdev_trig_interval_show,
- usbdev_trig_interval_store);
-
-static int usbdev_trig_notify(struct notifier_block *nb,
- unsigned long evt,
- void *data)
-{
- struct usb_device *usb_dev;
- struct usbdev_trig_data *td;
-
- if (evt != USB_DEVICE_ADD && evt != USB_DEVICE_REMOVE)
- return NOTIFY_DONE;
-
- usb_dev = data;
- td = container_of(nb, struct usbdev_trig_data, notifier);
-
- write_lock(&td->lock);
-
- if (strcmp(dev_name(&usb_dev->dev), td->device_name))
- goto done;
-
- if (evt == USB_DEVICE_ADD) {
- usb_get_dev(usb_dev);
- if (td->usb_dev != NULL)
- usb_put_dev(td->usb_dev);
- td->usb_dev = usb_dev;
- td->last_urbnum = atomic_read(&usb_dev->urbnum);
- } else if (evt == USB_DEVICE_REMOVE) {
- if (td->usb_dev != NULL) {
- usb_put_dev(td->usb_dev);
- td->usb_dev = NULL;
- }
- }
-
- usbdev_trig_update_state(td);
-
-done:
- write_unlock(&td->lock);
- return NOTIFY_DONE;
-}
-
-/* here's the real work! */
-static void usbdev_trig_timer(unsigned long arg)
-{
- struct usbdev_trig_data *td = (struct usbdev_trig_data *)arg;
- int new_urbnum;
-
- write_lock(&td->lock);
-
- if (!td->usb_dev || td->interval == 0) {
- /*
- * we don't need to do timer work, just reflect device presence
- */
- if (td->usb_dev)
- led_set_brightness(td->led_cdev, LED_FULL);
- else
- led_set_brightness(td->led_cdev, LED_OFF);
-
- goto no_restart;
- }
-
- if (td->interval)
- new_urbnum = atomic_read(&td->usb_dev->urbnum);
- else
- new_urbnum = 0;
-
- if (td->usb_dev) {
- /*
- * Base state is ON (device is present). If there's no device,
- * we don't get this far and the LED is off.
- * OFF -> ON always
- * ON -> OFF on activity
- */
- if (td->led_cdev->brightness == LED_OFF)
- led_set_brightness(td->led_cdev, LED_FULL);
- else if (td->last_urbnum != new_urbnum)
- led_set_brightness(td->led_cdev, LED_OFF);
- } else {
- /*
- * base state is OFF
- * ON -> OFF always
- * OFF -> ON on activity
- */
- if (td->led_cdev->brightness == LED_FULL)
- led_set_brightness(td->led_cdev, LED_OFF);
- else if (td->last_urbnum != new_urbnum)
- led_set_brightness(td->led_cdev, LED_FULL);
- }
-
- td->last_urbnum = new_urbnum;
- mod_timer(&td->timer, jiffies + td->interval);
-
-no_restart:
- write_unlock(&td->lock);
-}
-
-static void usbdev_trig_activate(struct led_classdev *led_cdev)
-{
- struct usbdev_trig_data *td;
- int rc;
-
- td = kzalloc(sizeof(struct usbdev_trig_data), GFP_KERNEL);
- if (!td)
- return;
-
- rwlock_init(&td->lock);
-
- td->notifier.notifier_call = usbdev_trig_notify;
- td->notifier.priority = 10;
-
- setup_timer(&td->timer, usbdev_trig_timer, (unsigned long) td);
-
- td->led_cdev = led_cdev;
- td->interval = msecs_to_jiffies(50);
-
- led_cdev->trigger_data = td;
-
- rc = device_create_file(led_cdev->dev, &dev_attr_device_name);
- if (rc)
- goto err_out;
-
- rc = device_create_file(led_cdev->dev, &dev_attr_activity_interval);
- if (rc)
- goto err_out_device_name;
-
- usb_register_notify(&td->notifier);
- return;
-
-err_out_device_name:
- device_remove_file(led_cdev->dev, &dev_attr_device_name);
-err_out:
- led_cdev->trigger_data = NULL;
- kfree(td);
-}
-
-static void usbdev_trig_deactivate(struct led_classdev *led_cdev)
-{
- struct usbdev_trig_data *td = led_cdev->trigger_data;
-
- if (td) {
- usb_unregister_notify(&td->notifier);
-
- device_remove_file(led_cdev->dev, &dev_attr_device_name);
- device_remove_file(led_cdev->dev, &dev_attr_activity_interval);
-
- write_lock(&td->lock);
-
- if (td->usb_dev) {
- usb_put_dev(td->usb_dev);
- td->usb_dev = NULL;
- }
-
- write_unlock(&td->lock);
-
- del_timer_sync(&td->timer);
-
- kfree(td);
- }
-}
-
-static struct led_trigger usbdev_led_trigger = {
- .name = "usbdev",
- .activate = usbdev_trig_activate,
- .deactivate = usbdev_trig_deactivate,
-};
-
-static int __init usbdev_trig_init(void)
-{
- return led_trigger_register(&usbdev_led_trigger);
-}
-
-static void __exit usbdev_trig_exit(void)
-{
- led_trigger_unregister(&usbdev_led_trigger);
-}
-
-module_init(usbdev_trig_init);
-module_exit(usbdev_trig_exit);
-
-MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
-MODULE_DESCRIPTION("USB device LED trigger");
-MODULE_LICENSE("GPL v2");