This commit introduces a NETDEV trigger for named device
activity. Available triggers are link, rx, and tx.
Signed-off-by: Ben Whitten <ben.whit...@gmail.com>
---
.../ABI/testing/sysfs-class-led-trigger-netdev | 45 +++
drivers/leds/trigger/Kconfig | 7 +
drivers/leds/trigger/Makefile | 1 +
drivers/leds/trigger/ledtrig-netdev.c | 428 +++++++++++++++++++++
4 files changed, 481 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-class-led-trigger-netdev
create mode 100644 drivers/leds/trigger/ledtrig-netdev.c
diff --git a/Documentation/ABI/testing/sysfs-class-led-trigger-netdev
b/Documentation/ABI/testing/sysfs-class-led-trigger-netdev
new file mode 100644
index 0000000..2c917df
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-led-trigger-netdev
@@ -0,0 +1,45 @@
+What: /sys/class/leds/<led>/device_name
+Date: Nov 2017
+KernelVersion: 4.15
+Contact: linux-l...@vger.kernel.org
+Description:
+ Specifies the network device name to monitor.
+
+What: /sys/class/leds/<led>/interval
+Date: Nov 2017
+KernelVersion: 4.15
+Contact: linux-l...@vger.kernel.org
+Description:
+ Specifies the duration of the LED blink in milliseconds.
+ Defaults to 50 ms.
+
+What: /sys/class/leds/<led>/link
+Date: Nov 2017
+KernelVersion: 4.15
+Contact: linux-l...@vger.kernel.org
+Description:
+ Signal the link state of the named network device.
+ If set to 0 (default), the LED's normal state is off.
+ If set to 1, the LED's normal state reflects the link state
+ of the named network device.
+ Setting this value also immediately changes the LED state.
+
+What: /sys/class/leds/<led>/tx
+Date: Nov 2017
+KernelVersion: 4.15
+Contact: linux-l...@vger.kernel.org
+Description:
+ Signal transmission of data on the named network device.
+ If set to 0 (default), the LED will not blink on transmission.
+ If set to 1, the LED will blink for the milliseconds specified
+ in interval to signal transmission.
+
+What: /sys/class/leds/<led>/rx
+Date: Nov 2017
+KernelVersion: 4.15
+Contact: linux-l...@vger.kernel.org
+Description:
+ Signal reception of data on the named network device.
+ If set to 0 (default), the LED will not blink on reception.
+ If set to 1, the LED will blink for the milliseconds specified
+ in interval to signal reception.
diff --git a/drivers/leds/trigger/Kconfig b/drivers/leds/trigger/Kconfig
index 3f9ddb9..4ec1853 100644
--- a/drivers/leds/trigger/Kconfig
+++ b/drivers/leds/trigger/Kconfig
@@ -126,4 +126,11 @@ config LEDS_TRIGGER_PANIC
a different trigger.
If unsure, say Y.
+config LEDS_TRIGGER_NETDEV
+ tristate "LED Netdev Trigger"
+ depends on NET && LEDS_TRIGGERS
+ help
+ This allows LEDs to be controlled by network device activity.
+ If unsure, say Y.
+
endif # LEDS_TRIGGERS
diff --git a/drivers/leds/trigger/Makefile b/drivers/leds/trigger/Makefile
index 9f2e868..59e163d 100644
--- a/drivers/leds/trigger/Makefile
+++ b/drivers/leds/trigger/Makefile
@@ -11,3 +11,4 @@ obj-$(CONFIG_LEDS_TRIGGER_DEFAULT_ON) += ledtrig-default-on.o
obj-$(CONFIG_LEDS_TRIGGER_TRANSIENT) += ledtrig-transient.o
obj-$(CONFIG_LEDS_TRIGGER_CAMERA) += ledtrig-camera.o
obj-$(CONFIG_LEDS_TRIGGER_PANIC) += ledtrig-panic.o
+obj-$(CONFIG_LEDS_TRIGGER_NETDEV) += ledtrig-netdev.o
diff --git a/drivers/leds/trigger/ledtrig-netdev.c
b/drivers/leds/trigger/ledtrig-netdev.c
new file mode 100644
index 0000000..2953b41
--- /dev/null
+++ b/drivers/leds/trigger/ledtrig-netdev.c
@@ -0,0 +1,428 @@
+/*
+ * LED Kernel Netdev Trigger
+ *
+ * Toggles the LED to reflect the link and traffic state of a named net device
+ *
+ * Copyright 2017 Ben Whitten <ben.whit...@gmail.com>
+ *
+ * Copyright 2007 Oliver Jowett <oli...@opencloud.com>
+ *
+ * Derived from ledtrig-timer.c which is:
+ * Copyright 2005-2006 Openedhand Ltd.
+ * Author: Richard Purdie <rpur...@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/netdevice.h>
+#include <linux/timer.h>
+#include <linux/ctype.h>
+#include <linux/atomic.h>
+#include <linux/leds.h>
+
+/*
+ * Configurable sysfs attributes:
+ *
+ * device_name - network device name to monitor
+ *
+ * interval - duration of LED blink, in milliseconds
+ *
+ * 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
+ *
+ */
+
+struct led_netdev_data {
+ spinlock_t lock;
+
+ struct delayed_work work;
+ struct notifier_block notifier;
+
+ struct led_classdev *led_cdev;
+ struct net_device *net_dev;
+
+ char device_name[IFNAMSIZ];
+ atomic_t interval;
+ unsigned int last_activity;
+
+ unsigned long mode;
+#define LED_BLINK_link 0
+#define LED_BLINK_tx 1
+#define LED_BLINK_rx 2
+#define LED_MODE_LINKUP 3
+};
+
+static void set_baseline_state(struct led_netdev_data *trigger_data)
+{
+ if (!test_bit(LED_MODE_LINKUP, &trigger_data->mode))
+ led_set_brightness(trigger_data->led_cdev, LED_OFF);
+ else {
+ if (test_bit(LED_BLINK_link, &trigger_data->mode))
+ led_set_brightness(trigger_data->led_cdev, LED_FULL);
+
+ if (test_bit(LED_BLINK_tx, &trigger_data->mode) ||
+ test_bit(LED_BLINK_rx, &trigger_data->mode))
+ schedule_delayed_work(&trigger_data->work,
+ atomic_read(&trigger_data->interval));
+ }
+}
+
+static ssize_t 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;
+ ssize_t len;
+
+ spin_lock_bh(&trigger_data->lock);
+ len = sprintf(buf, "%s\n", trigger_data->device_name);
+ spin_unlock_bh(&trigger_data->lock);
+
+ return len;
+}
+
+static ssize_t 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 >= IFNAMSIZ)
+ return -EINVAL;
+
+ cancel_delayed_work_sync(&trigger_data->work);
+
+ spin_lock_bh(&trigger_data->lock);
+
+ if (trigger_data->net_dev) {
+ dev_put(trigger_data->net_dev);
+ trigger_data->net_dev = NULL;
+ }
+
+ strncpy(trigger_data->device_name, buf, size);
+ if (size > 0 && trigger_data->device_name[size - 1] == '\n')
+ trigger_data->device_name[size - 1] = 0;
+
+ if (trigger_data->device_name[0] != 0)
+ trigger_data->net_dev =
+ dev_get_by_name(&init_net, trigger_data->device_name);
+
+ clear_bit(LED_MODE_LINKUP, &trigger_data->mode);
+ if (trigger_data->net_dev != NULL)
+ if (netif_carrier_ok(trigger_data->net_dev))
+ set_bit(LED_MODE_LINKUP, &trigger_data->mode);
+
+ trigger_data->last_activity = 0;
+
+ set_baseline_state(trigger_data);
+ spin_unlock_bh(&trigger_data->lock);
+
+ return size;
+}
+
+static DEVICE_ATTR_RW(device_name);
+
+#define led_mode_flags_attr(field) \
+static ssize_t field##_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; \
+ \
+ return sprintf(buf, "%u\n", test_bit(LED_BLINK_##field, \
+ &trigger_data->mode)); \
+} \
+static ssize_t field##_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; \
+ unsigned long state; \
+ int ret; \
+ \
+ ret = kstrtoul(buf, 0, &state); \
+ if (ret) \
+ return ret; \
+ \
+ cancel_delayed_work_sync(&trigger_data->work); \
+ \
+ if (state) \
+ set_bit(LED_BLINK_##field, &trigger_data->mode); \
+ else \
+ clear_bit(LED_BLINK_##field, &trigger_data->mode); \
+ \
+ set_baseline_state(trigger_data); \
+ \
+ return size; \
+} \
+static DEVICE_ATTR_RW(field);
+
+led_mode_flags_attr(link);
+led_mode_flags_attr(rx);
+led_mode_flags_attr(tx);
+
+static ssize_t 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;
+
+ return sprintf(buf, "%u\n",
+ jiffies_to_msecs(atomic_read(&trigger_data->interval)));
+}
+
+static ssize_t 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;
+ unsigned long value;
+ int ret;
+
+ ret = kstrtoul(buf, 0, &value);
+ if (ret)
+ return ret;
+
+ /* impose some basic bounds on the timer interval */
+ if (value >= 5 && value <= 10000) {
+ cancel_delayed_work_sync(&trigger_data->work);
+
+ atomic_set(&trigger_data->interval, msecs_to_jiffies(value));
+ set_baseline_state(trigger_data); /* resets timer */
+ }
+
+ return size;
+}
+
+static DEVICE_ATTR_RW(interval);
+
+static int netdev_trig_notify(struct notifier_block *nb,
+ unsigned long evt, void *dv)
+{
+ struct net_device *dev =
+ netdev_notifier_info_to_dev((struct netdev_notifier_info *)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
+ && evt != NETDEV_CHANGENAME)
+ return NOTIFY_DONE;
+
+ if (strcmp(dev->name, trigger_data->device_name))
+ return NOTIFY_DONE;
+
+ cancel_delayed_work_sync(&trigger_data->work);
+
+ spin_lock_bh(&trigger_data->lock);
+
+ clear_bit(LED_MODE_LINKUP, &trigger_data->mode);
+ switch (evt) {
+ case NETDEV_REGISTER:
+ if (trigger_data->net_dev)
+ dev_put(trigger_data->net_dev);
+ dev_hold(dev);
+ trigger_data->net_dev = dev;
+ break;
+ case NETDEV_CHANGENAME:
+ case NETDEV_UNREGISTER:
+ if (trigger_data->net_dev) {
+ dev_put(trigger_data->net_dev);
+ trigger_data->net_dev = NULL;
+ }
+ break;
+ case NETDEV_UP:
+ case NETDEV_CHANGE:
+ if (netif_carrier_ok(dev))
+ set_bit(LED_MODE_LINKUP, &trigger_data->mode);
+ break;
+ }
+
+ set_baseline_state(trigger_data);
+
+ spin_unlock_bh(&trigger_data->lock);
+
+ return NOTIFY_DONE;
+}
+
+/* here's the real work! */
+static void netdev_trig_work(struct work_struct *work)
+{
+ struct led_netdev_data *trigger_data = container_of(work,
+ struct
+ led_netdev_data,
+ work.work);
+ struct rtnl_link_stats64 *dev_stats;
+ unsigned int new_activity;
+ struct rtnl_link_stats64 temp;
+
+ if (!test_bit(LED_MODE_LINKUP, &trigger_data->mode) ||
+ !trigger_data->net_dev ||
+ (!test_bit(LED_BLINK_tx, &trigger_data->mode) &&
+ !test_bit(LED_BLINK_rx, &trigger_data->mode))) {
+ /* we don't need to do timer work, just reflect link state. */
+ led_set_brightness(trigger_data->led_cdev,
+ (test_bit
+ (LED_BLINK_link, &trigger_data->mode)
+ && test_bit(LED_MODE_LINKUP,
+ &trigger_data->mode
+ ) ? LED_FULL : LED_OFF));
+ return;
+ }
+
+ dev_stats = dev_get_stats(trigger_data->net_dev, &temp);
+ new_activity =
+ (test_bit(LED_BLINK_tx, &trigger_data->mode) ?
+ dev_stats->tx_packets : 0) +
+ (test_bit(LED_BLINK_rx, &trigger_data->mode) ?
+ dev_stats->rx_packets : 0);
+
+ if (test_bit(LED_BLINK_link, &trigger_data->mode)) {
+ /* 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;
+ schedule_delayed_work(&trigger_data->work,
+ atomic_read(&trigger_data->interval));
+}
+
+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;
+
+ spin_lock_init(&trigger_data->lock);
+
+ trigger_data->notifier.notifier_call = netdev_trig_notify;
+ trigger_data->notifier.priority = 10;
+
+ INIT_DELAYED_WORK(&trigger_data->work, netdev_trig_work);
+
+ trigger_data->led_cdev = led_cdev;
+ trigger_data->net_dev = NULL;
+ trigger_data->device_name[0] = 0;
+
+ trigger_data->mode = 0;
+ atomic_set(&trigger_data->interval, msecs_to_jiffies(50));
+ 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_link);
+ if (rc)
+ goto err_out_device_name;
+ rc = device_create_file(led_cdev->dev, &dev_attr_rx);
+ if (rc)
+ goto err_out_link;
+ rc = device_create_file(led_cdev->dev, &dev_attr_tx);
+ if (rc)
+ goto err_out_rx;
+ rc = device_create_file(led_cdev->dev, &dev_attr_interval);
+ if (rc)
+ goto err_out_tx;
+ rc = register_netdevice_notifier(&trigger_data->notifier);
+ if (rc)
+ goto err_out_interval;
+ return;
+
+err_out_interval:
+ device_remove_file(led_cdev->dev, &dev_attr_interval);
+err_out_tx:
+ device_remove_file(led_cdev->dev, &dev_attr_tx);
+err_out_rx:
+ device_remove_file(led_cdev->dev, &dev_attr_rx);
+err_out_link:
+ device_remove_file(led_cdev->dev, &dev_attr_link);
+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_link);
+ device_remove_file(led_cdev->dev, &dev_attr_rx);
+ device_remove_file(led_cdev->dev, &dev_attr_tx);
+ device_remove_file(led_cdev->dev, &dev_attr_interval);
+
+ cancel_delayed_work_sync(&trigger_data->work);
+
+ if (trigger_data->net_dev)
+ dev_put(trigger_data->net_dev);
+
+ 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("Ben Whitten <ben.whit...@gmail.com>");
+MODULE_AUTHOR("Oliver Jowett <oli...@opencloud.com>");
+MODULE_DESCRIPTION("Netdev LED trigger");
+MODULE_LICENSE("GPL");
--
2.7.4
