--- /dev/null
+/*
+ * LED Kernel Netdev Trigger
+ *
+ * Toggles the LED to reflect the link and traffic state of a named net device
+ *
+ * Copyright 2007 Oliver Jowett <oliver@opencloud.com>
+ *
+ * Derived from ledtrig-timer.c which is:
+ * 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/netdevice.h>
+#include <linux/timer.h>
+#include <linux/ctype.h>
+#include <linux/leds.h>
+#include "leds.h"
+
+/*
+ * Configurable sysfs attributes:
+ *
+ * device_name - network device name to monitor
+ *
+ * interval - duration of LED blink, in milliseconds
+ *
+ * mode - either "none" (LED is off) or a space separated list of one or more of:
+ * link: LED's normal state reflects whether the link is up (has carrier) or not
+ * tx: LED blinks on transmitted data
+ * rx: LED blinks on receive data
+ *
+ * Some suggestions:
+ *
+ * Simple link status LED:
+ * $ echo netdev >someled/trigger
+ * $ echo eth0 >someled/device_name
+ * $ echo link >someled/mode
+ *
+ * Ethernet-style link/activity LED:
+ * $ echo netdev >someled/trigger
+ * $ echo eth0 >someled/device_name
+ * $ echo "link tx rx" >someled/mode
+ *
+ * Modem-style tx/rx LEDs:
+ * $ echo netdev >led1/trigger
+ * $ echo ppp0 >led1/device_name
+ * $ echo tx >led1/mode
+ * $ echo netdev >led2/trigger
+ * $ echo ppp0 >led2/device_name
+ * $ echo rx >led2/mode
+ *
+ */
+
+#define MODE_LINK 1
+#define MODE_TX 2
+#define MODE_RX 4
+
+struct led_netdev_data {
+ rwlock_t lock;
+
+ struct timer_list timer;
+ struct notifier_block notifier;
+
+ struct led_classdev *led_cdev;
+ struct net_device *net_dev;
+
+ char device_name[IFNAMSIZ];
+ unsigned interval;
+ unsigned mode;
+ unsigned link_up;
+ unsigned last_activity;
+};
+
+static void set_baseline_state(struct led_netdev_data *trigger_data)
+{
+ if ((trigger_data->mode & MODE_LINK) != 0 && trigger_data->link_up)
+ led_set_brightness(trigger_data->led_cdev, LED_FULL);
+ else
+ led_set_brightness(trigger_data->led_cdev, LED_OFF);
+
+ if ((trigger_data->mode & (MODE_TX | MODE_RX)) != 0 && trigger_data->link_up)
+ mod_timer(&trigger_data->timer, jiffies + trigger_data->interval);
+ else
+ del_timer(&trigger_data->timer);
+}
+
+static ssize_t led_device_name_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_netdev_data *trigger_data = led_cdev->trigger_data;
+
+ read_lock(&trigger_data->lock);
+ sprintf(buf, "%s\n", trigger_data->device_name);
+ read_unlock(&trigger_data->lock);
+
+ return strlen(buf) + 1;
+}
+
+static ssize_t led_device_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 led_netdev_data *trigger_data = led_cdev->trigger_data;
+
+ if (size < 0 || size >= IFNAMSIZ)
+ return -EINVAL;
+
+ write_lock(&trigger_data->lock);
+
+ strcpy(trigger_data->device_name, buf);
+ if (size > 0 && trigger_data->device_name[size-1] == '\n')
+ trigger_data->device_name[size-1] = 0;
+
+ if (trigger_data->device_name[0] != 0) {
+ /* check for existing device to update from */
+ trigger_data->net_dev = dev_get_by_name(trigger_data->device_name);
+ if (trigger_data->net_dev != NULL)
+ trigger_data->link_up = (dev_get_flags(trigger_data->net_dev) & IFF_LOWER_UP) != 0;
+ set_baseline_state(trigger_data); /* updates LEDs, may start timers */
+ }
+
+ write_unlock(&trigger_data->lock);
+ return size;
+}
+
+static DEVICE_ATTR(device_name, 0644, led_device_name_show, led_device_name_store);
+
+static ssize_t led_mode_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_netdev_data *trigger_data = led_cdev->trigger_data;
+
+ read_lock(&trigger_data->lock);
+
+ if (trigger_data->mode == 0) {
+ strcpy(buf, "none\n");
+ } else {
+ if (trigger_data->mode & MODE_LINK)
+ strcat(buf, "link ");
+ if (trigger_data->mode & MODE_TX)
+ strcat(buf, "tx ");
+ if (trigger_data->mode & MODE_RX)
+ strcat(buf, "rx ");
+ strcat(buf, "\n");
+ }
+
+ read_unlock(&trigger_data->lock);
+
+ return strlen(buf)+1;
+}
+
+static ssize_t led_mode_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t size)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_netdev_data *trigger_data = led_cdev->trigger_data;
+ char copybuf[1024];
+ int new_mode = -1;
+ char *p, *token;
+
+ /* take a copy since we don't want to trash the inbound buffer when using strsep */
+ strncpy(copybuf, buf, sizeof(copybuf));
+ copybuf[1023] = 0;
+ p = copybuf;
+
+ while ((token = strsep(&p, " \t\n")) != NULL) {
+ if (!*token)
+ continue;
+
+ if (new_mode == -1)
+ new_mode = 0;
+
+ if (!strcmp(token, "none"))
+ new_mode = 0;
+ else if (!strcmp(token, "tx"))
+ new_mode |= MODE_TX;
+ else if (!strcmp(token, "rx"))
+ new_mode |= MODE_RX;
+ else if (!strcmp(token, "link"))
+ new_mode |= MODE_LINK;
+ else
+ return -EINVAL;
+ }
+
+ if (new_mode == -1)
+ return -EINVAL;
+
+ write_lock(&trigger_data->lock);
+ trigger_data->mode = new_mode;
+ set_baseline_state(trigger_data);
+ write_unlock(&trigger_data->lock);
+
+ return size;
+}
+
+static DEVICE_ATTR(mode, 0644, led_mode_show, led_mode_store);
+
+static ssize_t led_interval_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_netdev_data *trigger_data = led_cdev->trigger_data;
+
+ read_lock(&trigger_data->lock);
+ sprintf(buf, "%u\n", jiffies_to_msecs(trigger_data->interval));
+ read_unlock(&trigger_data->lock);
+
+ return strlen(buf) + 1;
+}
+
+static ssize_t led_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 led_netdev_data *trigger_data = 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++;
+
+ /* impose some basic bounds on the timer interval */
+ if (count == size && value >= 5 && value <= 10000) {
+ write_lock(&trigger_data->lock);
+ trigger_data->interval = msecs_to_jiffies(value);
+ set_baseline_state(trigger_data); // resets timer
+ write_unlock(&trigger_data->lock);
+ ret = count;
+ }
+
+ return ret;
+}
+
+static DEVICE_ATTR(interval, 0644, led_interval_show, led_interval_store);
+
+static int netdev_trig_notify(struct notifier_block *nb,
+ unsigned long evt,
+ void *dv)
+{
+ struct net_device *dev = dv;
+ struct led_netdev_data *trigger_data = container_of(nb, struct led_netdev_data, notifier);
+
+ if (evt != NETDEV_UP && evt != NETDEV_DOWN && evt != NETDEV_CHANGE && evt != NETDEV_REGISTER && evt != NETDEV_UNREGISTER)
+ return NOTIFY_DONE;
+
+ write_lock(&trigger_data->lock);
+
+ if (strcmp(dev->name, trigger_data->device_name))
+ goto done;
+
+ if (evt == NETDEV_REGISTER) {
+ if (trigger_data->net_dev != NULL)
+ dev_put(trigger_data->net_dev);
+ dev_hold(dev);
+ trigger_data->net_dev = dev;
+ trigger_data->link_up = 0;
+ goto done;
+ }
+
+ if (evt == NETDEV_UNREGISTER && trigger_data->net_dev != NULL) {
+ dev_put(trigger_data->net_dev);
+ trigger_data->net_dev = NULL;
+ goto done;
+ }
+
+ /* UP / DOWN / CHANGE */
+
+ trigger_data->link_up = (evt != NETDEV_DOWN && netif_carrier_ok(dev));
+ set_baseline_state(trigger_data);
+
+done:
+ write_unlock(&trigger_data->lock);
+ return NOTIFY_DONE;
+}
+
+/* here's the real work! */
+static void netdev_trig_timer(unsigned long arg)
+{
+ struct led_netdev_data *trigger_data = (struct led_netdev_data *)arg;
+ struct net_device_stats *dev_stats;
+ unsigned new_activity;
+
+ write_lock(&trigger_data->lock);
+
+ if (!trigger_data->link_up || !trigger_data->net_dev || (trigger_data->mode & (MODE_TX | MODE_RX)) == 0) {
+ /* we don't need to do timer work, just reflect link state. */
+ led_set_brightness(trigger_data->led_cdev, ((trigger_data->mode & MODE_LINK) != 0 && trigger_data->link_up) ? LED_FULL : LED_OFF);
+ goto no_restart;
+ }
+
+ dev_stats = trigger_data->net_dev->get_stats(trigger_data->net_dev);
+ new_activity =
+ ((trigger_data->mode & MODE_TX) ? dev_stats->tx_packets : 0) +
+ ((trigger_data->mode & MODE_RX) ? dev_stats->rx_packets : 0);
+
+ if (trigger_data->mode & MODE_LINK) {
+ /* base state is ON (link present) */
+ /* if there's no link, we don't get this far and the LED is off */
+
+ /* OFF -> ON always */
+ /* ON -> OFF on activity */
+ if (trigger_data->led_cdev->brightness == LED_OFF) {
+ led_set_brightness(trigger_data->led_cdev, LED_FULL);
+ } else if (trigger_data->last_activity != new_activity) {
+ led_set_brightness(trigger_data->led_cdev, LED_OFF);
+ }
+ } else {
+ /* base state is OFF */
+ /* ON -> OFF always */
+ /* OFF -> ON on activity */
+ if (trigger_data->led_cdev->brightness == LED_FULL) {
+ led_set_brightness(trigger_data->led_cdev, LED_OFF);
+ } else if (trigger_data->last_activity != new_activity) {
+ led_set_brightness(trigger_data->led_cdev, LED_FULL);
+ }
+ }
+
+ trigger_data->last_activity = new_activity;
+ mod_timer(&trigger_data->timer, jiffies + trigger_data->interval);
+
+no_restart:
+ write_unlock(&trigger_data->lock);
+}
+
+static void netdev_trig_activate(struct led_classdev *led_cdev)
+{
+ struct led_netdev_data *trigger_data;
+ int rc;
+
+ trigger_data = kzalloc(sizeof(struct led_netdev_data), GFP_KERNEL);
+ if (!trigger_data)
+ return;
+
+ rwlock_init(&trigger_data->lock);
+
+ trigger_data->notifier.notifier_call = netdev_trig_notify;
+ trigger_data->notifier.priority = 10;
+
+ setup_timer(&trigger_data->timer, netdev_trig_timer, (unsigned long) trigger_data);
+
+ trigger_data->led_cdev = led_cdev;
+ trigger_data->net_dev = NULL;
+ trigger_data->device_name[0] = 0;
+
+ trigger_data->mode = 0;
+ trigger_data->interval = msecs_to_jiffies(50);
+ trigger_data->link_up = 0;
+ trigger_data->last_activity = 0;
+
+ led_cdev->trigger_data = trigger_data;
+
+ 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_mode);
+ if (rc)
+ goto err_out_device_name;
+ rc = device_create_file(led_cdev->dev, &dev_attr_interval);
+ if (rc)
+ goto err_out_mode;
+
+ register_netdevice_notifier(&trigger_data->notifier);
+ return;
+
+err_out_mode:
+ device_remove_file(led_cdev->dev, &dev_attr_mode);
+err_out_device_name:
+ device_remove_file(led_cdev->dev, &dev_attr_device_name);
+err_out:
+ led_cdev->trigger_data = NULL;
+ kfree(trigger_data);
+}
+
+static void netdev_trig_deactivate(struct led_classdev *led_cdev)
+{
+ struct led_netdev_data *trigger_data = led_cdev->trigger_data;
+
+ if (trigger_data) {
+ unregister_netdevice_notifier(&trigger_data->notifier);
+
+ device_remove_file(led_cdev->dev, &dev_attr_device_name);
+ device_remove_file(led_cdev->dev, &dev_attr_mode);
+ device_remove_file(led_cdev->dev, &dev_attr_interval);
+
+ write_lock(&trigger_data->lock);
+
+ if (trigger_data->net_dev) {
+ dev_put(trigger_data->net_dev);
+ trigger_data->net_dev = NULL;
+ }
+
+ write_unlock(&trigger_data->lock);
+
+ del_timer_sync(&trigger_data->timer);
+
+ kfree(trigger_data);
+ }
+}
+
+static struct led_trigger netdev_led_trigger = {
+ .name = "netdev",
+ .activate = netdev_trig_activate,
+ .deactivate = netdev_trig_deactivate,
+};
+
+static int __init netdev_trig_init(void)
+{
+ return led_trigger_register(&netdev_led_trigger);
+}
+
+static void __exit netdev_trig_exit(void)
+{
+ led_trigger_unregister(&netdev_led_trigger);
+}
+
+module_init(netdev_trig_init);
+module_exit(netdev_trig_exit);
+
+MODULE_AUTHOR("Oliver Jowett <oliver@opencloud.com>");
+MODULE_DESCRIPTION("Netdev LED trigger");
+MODULE_LICENSE("GPL");
projects / openwrt / openwrt.git / blobdiff