// SPDX-License-Identifier: GPL-2.0 // Copyright 2017 Ben Whitten // Copyright 2007 Oliver Jowett // // LED Kernel Netdev Trigger // // Toggles the LED to reflect the link and traffic state of a named net device // // Derived from ledtrig-timer.c which is: // Copyright 2005-2006 Openedhand Ltd. // Author: Richard Purdie #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "../leds.h" #define NETDEV_LED_DEFAULT_INTERVAL 50 /* * 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 * * Note: If the user selects a mode that is not supported by hw, default * behavior is to fall back to software control of the LED. However not every * hw supports software control. LED callbacks brightness_set() and * brightness_set_blocking() are NULL in this case. hw_control_is_supported() * should use available means supported by hw to inform the user that selected * mode isn't supported by hw. This could be switching off the LED or any * hw blink mode. If software control fallback isn't possible, we return * -EOPNOTSUPP to the user, but still store the selected mode. This is needed * in case an intermediate unsupported mode is necessary to switch from one * supported mode to another. */ struct led_netdev_data { struct mutex 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; int link_speed; __ETHTOOL_DECLARE_LINK_MODE_MASK(supported_link_modes); u8 duplex; bool carrier_link_up; bool hw_control; }; static const struct attribute_group netdev_trig_link_speed_attrs_group; static void set_baseline_state(struct led_netdev_data *trigger_data) { int current_brightness; struct led_classdev *led_cdev = trigger_data->led_cdev; /* Already validated, hw control is possible with the requested mode */ if (trigger_data->hw_control) { led_cdev->hw_control_set(led_cdev, trigger_data->mode); return; } current_brightness = led_cdev->brightness; if (current_brightness) led_cdev->blink_brightness = current_brightness; if (!led_cdev->blink_brightness) led_cdev->blink_brightness = led_cdev->max_brightness; if (!trigger_data->carrier_link_up) { led_set_brightness(led_cdev, LED_OFF); } else { bool blink_on = false; if (test_bit(TRIGGER_NETDEV_LINK, &trigger_data->mode)) blink_on = true; if (test_bit(TRIGGER_NETDEV_LINK_10, &trigger_data->mode) && trigger_data->link_speed == SPEED_10) blink_on = true; if (test_bit(TRIGGER_NETDEV_LINK_100, &trigger_data->mode) && trigger_data->link_speed == SPEED_100) blink_on = true; if (test_bit(TRIGGER_NETDEV_LINK_1000, &trigger_data->mode) && trigger_data->link_speed == SPEED_1000) blink_on = true; if (test_bit(TRIGGER_NETDEV_LINK_2500, &trigger_data->mode) && trigger_data->link_speed == SPEED_2500) blink_on = true; if (test_bit(TRIGGER_NETDEV_LINK_5000, &trigger_data->mode) && trigger_data->link_speed == SPEED_5000) blink_on = true; if (test_bit(TRIGGER_NETDEV_LINK_10000, &trigger_data->mode) && trigger_data->link_speed == SPEED_10000) blink_on = true; if (test_bit(TRIGGER_NETDEV_HALF_DUPLEX, &trigger_data->mode) && trigger_data->duplex == DUPLEX_HALF) blink_on = true; if (test_bit(TRIGGER_NETDEV_FULL_DUPLEX, &trigger_data->mode) && trigger_data->duplex == DUPLEX_FULL) blink_on = true; if (blink_on) led_set_brightness(led_cdev, led_cdev->blink_brightness); else led_set_brightness(led_cdev, LED_OFF); /* If we are looking for RX/TX start periodically * checking stats */ if (test_bit(TRIGGER_NETDEV_TX, &trigger_data->mode) || test_bit(TRIGGER_NETDEV_RX, &trigger_data->mode)) schedule_delayed_work(&trigger_data->work, 0); } } static bool supports_hw_control(struct led_classdev *led_cdev) { if (!led_cdev->hw_control_get || !led_cdev->hw_control_set || !led_cdev->hw_control_is_supported) return false; return !strcmp(led_cdev->hw_control_trigger, led_cdev->trigger->name); } /* * Validate the configured netdev is the same as the one associated with * the LED driver in hw control. */ static bool validate_net_dev(struct led_classdev *led_cdev, struct net_device *net_dev) { struct device *dev = led_cdev->hw_control_get_device(led_cdev); struct net_device *ndev; if (!dev) return false; ndev = to_net_dev(dev); return ndev == net_dev; } static bool can_hw_control(struct led_netdev_data *trigger_data) { unsigned long default_interval = msecs_to_jiffies(NETDEV_LED_DEFAULT_INTERVAL); unsigned int interval = atomic_read(&trigger_data->interval); struct led_classdev *led_cdev = trigger_data->led_cdev; int ret; if (!supports_hw_control(led_cdev)) return false; /* * Interval must be set to the default * value. Any different value is rejected if in hw * control. */ if (interval != default_interval) return false; /* * net_dev must be set with hw control, otherwise no * blinking can be happening and there is nothing to * offloaded. Additionally, for hw control to be * valid, the configured netdev must be the same as * netdev associated to the LED. */ if (!validate_net_dev(led_cdev, trigger_data->net_dev)) return false; /* Check if the requested mode is supported */ ret = led_cdev->hw_control_is_supported(led_cdev, trigger_data->mode); /* Fall back to software blinking if not supported */ if (ret == -EOPNOTSUPP) return false; if (ret) { dev_warn(led_cdev->dev, "Current mode check failed with error %d\n", ret); return false; } return true; } static void get_device_state(struct led_netdev_data *trigger_data) { struct ethtool_link_ksettings cmd; trigger_data->carrier_link_up = netif_carrier_ok(trigger_data->net_dev); if (__ethtool_get_link_ksettings(trigger_data->net_dev, &cmd)) return; if (trigger_data->carrier_link_up) { trigger_data->link_speed = cmd.base.speed; trigger_data->duplex = cmd.base.duplex; } /* * Have a local copy of the link speed supported to avoid rtnl lock every time * modes are refreshed on any change event */ linkmode_copy(trigger_data->supported_link_modes, cmd.link_modes.supported); } static ssize_t device_name_show(struct device *dev, struct device_attribute *attr, char *buf) { struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev); ssize_t len; mutex_lock(&trigger_data->lock); len = sprintf(buf, "%s\n", trigger_data->device_name); mutex_unlock(&trigger_data->lock); return len; } static int set_device_name(struct led_netdev_data *trigger_data, const char *name, size_t size) { if (size >= IFNAMSIZ) return -EINVAL; cancel_delayed_work_sync(&trigger_data->work); /* * Take RTNL lock before trigger_data lock to prevent potential * deadlock with netdev notifier registration. */ rtnl_lock(); mutex_lock(&trigger_data->lock); if (trigger_data->net_dev) { dev_put(trigger_data->net_dev); trigger_data->net_dev = NULL; } memcpy(trigger_data->device_name, name, size); trigger_data->device_name[size] = 0; 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); trigger_data->carrier_link_up = false; trigger_data->link_speed = SPEED_UNKNOWN; trigger_data->duplex = DUPLEX_UNKNOWN; if (trigger_data->net_dev) get_device_state(trigger_data); trigger_data->last_activity = 0; /* Skip if we're called from netdev_trig_activate() and hw_control is true */ if (!trigger_data->hw_control || led_get_trigger_data(trigger_data->led_cdev)) set_baseline_state(trigger_data); mutex_unlock(&trigger_data->lock); rtnl_unlock(); return 0; } static ssize_t device_name_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev); int ret; ret = set_device_name(trigger_data, buf, size); if (ret < 0) return ret; /* Refresh link_speed visibility */ sysfs_update_group(&dev->kobj, &netdev_trig_link_speed_attrs_group); return size; } static DEVICE_ATTR_RW(device_name); static ssize_t netdev_led_attr_show(struct device *dev, char *buf, enum led_trigger_netdev_modes attr) { struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev); int bit; switch (attr) { case TRIGGER_NETDEV_LINK: case TRIGGER_NETDEV_LINK_10: case TRIGGER_NETDEV_LINK_100: case TRIGGER_NETDEV_LINK_1000: case TRIGGER_NETDEV_LINK_2500: case TRIGGER_NETDEV_LINK_5000: case TRIGGER_NETDEV_LINK_10000: case TRIGGER_NETDEV_HALF_DUPLEX: case TRIGGER_NETDEV_FULL_DUPLEX: case TRIGGER_NETDEV_TX: case TRIGGER_NETDEV_RX: bit = attr; break; default: return -EINVAL; } return sprintf(buf, "%u\n", test_bit(bit, &trigger_data->mode)); } static ssize_t netdev_led_attr_store(struct device *dev, const char *buf, size_t size, enum led_trigger_netdev_modes attr) { struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev); struct led_classdev *led_cdev = trigger_data->led_cdev; unsigned long state, mode = trigger_data->mode; int ret; int bit; ret = kstrtoul(buf, 0, &state); if (ret) return ret; switch (attr) { case TRIGGER_NETDEV_LINK: case TRIGGER_NETDEV_LINK_10: case TRIGGER_NETDEV_LINK_100: case TRIGGER_NETDEV_LINK_1000: case TRIGGER_NETDEV_LINK_2500: case TRIGGER_NETDEV_LINK_5000: case TRIGGER_NETDEV_LINK_10000: case TRIGGER_NETDEV_HALF_DUPLEX: case TRIGGER_NETDEV_FULL_DUPLEX: case TRIGGER_NETDEV_TX: case TRIGGER_NETDEV_RX: bit = attr; break; default: return -EINVAL; } if (state) set_bit(bit, &mode); else clear_bit(bit, &mode); if (test_bit(TRIGGER_NETDEV_LINK, &mode) && (test_bit(TRIGGER_NETDEV_LINK_10, &mode) || test_bit(TRIGGER_NETDEV_LINK_100, &mode) || test_bit(TRIGGER_NETDEV_LINK_1000, &mode) || test_bit(TRIGGER_NETDEV_LINK_2500, &mode) || test_bit(TRIGGER_NETDEV_LINK_5000, &mode) || test_bit(TRIGGER_NETDEV_LINK_10000, &mode))) return -EINVAL; cancel_delayed_work_sync(&trigger_data->work); trigger_data->mode = mode; trigger_data->hw_control = can_hw_control(trigger_data); if (!led_cdev->brightness_set && !led_cdev->brightness_set_blocking && !trigger_data->hw_control) return -EOPNOTSUPP; set_baseline_state(trigger_data); return size; } #define DEFINE_NETDEV_TRIGGER(trigger_name, trigger) \ static ssize_t trigger_name##_show(struct device *dev, \ struct device_attribute *attr, char *buf) \ { \ return netdev_led_attr_show(dev, buf, trigger); \ } \ static ssize_t trigger_name##_store(struct device *dev, \ struct device_attribute *attr, const char *buf, size_t size) \ { \ return netdev_led_attr_store(dev, buf, size, trigger); \ } \ static DEVICE_ATTR_RW(trigger_name) DEFINE_NETDEV_TRIGGER(link, TRIGGER_NETDEV_LINK); DEFINE_NETDEV_TRIGGER(link_10, TRIGGER_NETDEV_LINK_10); DEFINE_NETDEV_TRIGGER(link_100, TRIGGER_NETDEV_LINK_100); DEFINE_NETDEV_TRIGGER(link_1000, TRIGGER_NETDEV_LINK_1000); DEFINE_NETDEV_TRIGGER(link_2500, TRIGGER_NETDEV_LINK_2500); DEFINE_NETDEV_TRIGGER(link_5000, TRIGGER_NETDEV_LINK_5000); DEFINE_NETDEV_TRIGGER(link_10000, TRIGGER_NETDEV_LINK_10000); DEFINE_NETDEV_TRIGGER(half_duplex, TRIGGER_NETDEV_HALF_DUPLEX); DEFINE_NETDEV_TRIGGER(full_duplex, TRIGGER_NETDEV_FULL_DUPLEX); DEFINE_NETDEV_TRIGGER(tx, TRIGGER_NETDEV_TX); DEFINE_NETDEV_TRIGGER(rx, TRIGGER_NETDEV_RX); static ssize_t interval_show(struct device *dev, struct device_attribute *attr, char *buf) { struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev); 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_netdev_data *trigger_data = led_trigger_get_drvdata(dev); unsigned long value; int ret; if (trigger_data->hw_control) return -EINVAL; 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 ssize_t offloaded_show(struct device *dev, struct device_attribute *attr, char *buf) { struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev); return sprintf(buf, "%d\n", trigger_data->hw_control); } static DEVICE_ATTR_RO(offloaded); #define CHECK_LINK_MODE_ATTR(link_speed) \ do { \ if (attr == &dev_attr_link_##link_speed.attr && \ link_ksettings.base.speed == SPEED_##link_speed) \ return attr->mode; \ } while (0) static umode_t netdev_trig_link_speed_visible(struct kobject *kobj, struct attribute *attr, int n) { struct device *dev = kobj_to_dev(kobj); struct led_netdev_data *trigger_data; unsigned long *supported_link_modes; u32 mode; trigger_data = led_trigger_get_drvdata(dev); supported_link_modes = trigger_data->supported_link_modes; /* * Search in the supported link mode mask a matching supported mode. * Stop at the first matching entry as we care only to check if a particular * speed is supported and not the kind. */ for_each_set_bit(mode, supported_link_modes, __ETHTOOL_LINK_MODE_MASK_NBITS) { struct ethtool_link_ksettings link_ksettings; ethtool_params_from_link_mode(&link_ksettings, mode); CHECK_LINK_MODE_ATTR(10); CHECK_LINK_MODE_ATTR(100); CHECK_LINK_MODE_ATTR(1000); CHECK_LINK_MODE_ATTR(2500); CHECK_LINK_MODE_ATTR(5000); CHECK_LINK_MODE_ATTR(10000); } return 0; } static struct attribute *netdev_trig_link_speed_attrs[] = { &dev_attr_link_10.attr, &dev_attr_link_100.attr, &dev_attr_link_1000.attr, &dev_attr_link_2500.attr, &dev_attr_link_5000.attr, &dev_attr_link_10000.attr, NULL }; static const struct attribute_group netdev_trig_link_speed_attrs_group = { .attrs = netdev_trig_link_speed_attrs, .is_visible = netdev_trig_link_speed_visible, }; static struct attribute *netdev_trig_attrs[] = { &dev_attr_device_name.attr, &dev_attr_link.attr, &dev_attr_full_duplex.attr, &dev_attr_half_duplex.attr, &dev_attr_rx.attr, &dev_attr_tx.attr, &dev_attr_interval.attr, &dev_attr_offloaded.attr, NULL }; static const struct attribute_group netdev_trig_attrs_group = { .attrs = netdev_trig_attrs, }; static const struct attribute_group *netdev_trig_groups[] = { &netdev_trig_attrs_group, &netdev_trig_link_speed_attrs_group, NULL, }; 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); struct led_classdev *led_cdev = trigger_data->led_cdev; if (evt != NETDEV_UP && evt != NETDEV_DOWN && evt != NETDEV_CHANGE && evt != NETDEV_REGISTER && evt != NETDEV_UNREGISTER && evt != NETDEV_CHANGENAME) return NOTIFY_DONE; if (!(dev == trigger_data->net_dev || (evt == NETDEV_CHANGENAME && !strcmp(dev->name, trigger_data->device_name)) || (evt == NETDEV_REGISTER && !strcmp(dev->name, trigger_data->device_name)))) return NOTIFY_DONE; cancel_delayed_work_sync(&trigger_data->work); mutex_lock(&trigger_data->lock); trigger_data->carrier_link_up = false; trigger_data->link_speed = SPEED_UNKNOWN; trigger_data->duplex = DUPLEX_UNKNOWN; switch (evt) { case NETDEV_CHANGENAME: get_device_state(trigger_data); fallthrough; case NETDEV_REGISTER: dev_put(trigger_data->net_dev); dev_hold(dev); trigger_data->net_dev = dev; break; case NETDEV_UNREGISTER: dev_put(trigger_data->net_dev); trigger_data->net_dev = NULL; break; case NETDEV_UP: case NETDEV_CHANGE: get_device_state(trigger_data); /* Refresh link_speed visibility */ if (evt == NETDEV_CHANGE) sysfs_update_group(&led_cdev->dev->kobj, &netdev_trig_link_speed_attrs_group); break; } set_baseline_state(trigger_data); mutex_unlock(&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; unsigned long interval; int invert; /* If we dont have a device, insure we are off */ if (!trigger_data->net_dev) { led_set_brightness(trigger_data->led_cdev, LED_OFF); return; } /* If we are not looking for RX/TX then return */ if (!test_bit(TRIGGER_NETDEV_TX, &trigger_data->mode) && !test_bit(TRIGGER_NETDEV_RX, &trigger_data->mode)) return; dev_stats = dev_get_stats(trigger_data->net_dev, &temp); new_activity = (test_bit(TRIGGER_NETDEV_TX, &trigger_data->mode) ? dev_stats->tx_packets : 0) + (test_bit(TRIGGER_NETDEV_RX, &trigger_data->mode) ? dev_stats->rx_packets : 0); if (trigger_data->last_activity != new_activity) { led_stop_software_blink(trigger_data->led_cdev); invert = test_bit(TRIGGER_NETDEV_LINK, &trigger_data->mode) || test_bit(TRIGGER_NETDEV_LINK_10, &trigger_data->mode) || test_bit(TRIGGER_NETDEV_LINK_100, &trigger_data->mode) || test_bit(TRIGGER_NETDEV_LINK_1000, &trigger_data->mode) || test_bit(TRIGGER_NETDEV_LINK_2500, &trigger_data->mode) || test_bit(TRIGGER_NETDEV_LINK_5000, &trigger_data->mode) || test_bit(TRIGGER_NETDEV_LINK_10000, &trigger_data->mode) || test_bit(TRIGGER_NETDEV_HALF_DUPLEX, &trigger_data->mode) || test_bit(TRIGGER_NETDEV_FULL_DUPLEX, &trigger_data->mode); interval = jiffies_to_msecs( atomic_read(&trigger_data->interval)); /* base state is ON (link present) */ led_blink_set_oneshot(trigger_data->led_cdev, &interval, &interval, invert); trigger_data->last_activity = new_activity; } schedule_delayed_work(&trigger_data->work, (atomic_read(&trigger_data->interval)*2)); } static int netdev_trig_activate(struct led_classdev *led_cdev) { struct led_netdev_data *trigger_data; unsigned long mode = 0; struct device *dev; int rc; trigger_data = kzalloc(sizeof(struct led_netdev_data), GFP_KERNEL); if (!trigger_data) return -ENOMEM; mutex_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(NETDEV_LED_DEFAULT_INTERVAL)); trigger_data->last_activity = 0; /* Check if hw control is active by default on the LED. * Init already enabled mode in hw control. */ if (supports_hw_control(led_cdev)) { dev = led_cdev->hw_control_get_device(led_cdev); if (dev) { const char *name = dev_name(dev); trigger_data->hw_control = true; set_device_name(trigger_data, name, strlen(name)); rc = led_cdev->hw_control_get(led_cdev, &mode); if (!rc) trigger_data->mode = mode; } } led_set_trigger_data(led_cdev, trigger_data); rc = register_netdevice_notifier(&trigger_data->notifier); if (rc) kfree(trigger_data); return rc; } static void netdev_trig_deactivate(struct led_classdev *led_cdev) { struct led_netdev_data *trigger_data = led_get_trigger_data(led_cdev); unregister_netdevice_notifier(&trigger_data->notifier); cancel_delayed_work_sync(&trigger_data->work); led_set_brightness(led_cdev, LED_OFF); 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, .groups = netdev_trig_groups, }; module_led_trigger(netdev_led_trigger); MODULE_AUTHOR("Ben Whitten "); MODULE_AUTHOR("Oliver Jowett "); MODULE_DESCRIPTION("Netdev LED trigger"); MODULE_LICENSE("GPL v2"); MODULE_ALIAS("ledtrig:netdev");