diff options
Diffstat (limited to 'drivers/leds/trigger/ledtrig-netdev.c')
-rw-r--r-- | drivers/leds/trigger/ledtrig-netdev.c | 620 |
1 files changed, 620 insertions, 0 deletions
diff --git a/drivers/leds/trigger/ledtrig-netdev.c b/drivers/leds/trigger/ledtrig-netdev.c new file mode 100644 index 0000000000..d76214fa9a --- /dev/null +++ b/drivers/leds/trigger/ledtrig-netdev.c @@ -0,0 +1,620 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright 2017 Ben Whitten <ben.whitten@gmail.com> +// Copyright 2007 Oliver Jowett <oliver@opencloud.com> +// +// 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 <rpurdie@openedhand.com> + +#include <linux/atomic.h> +#include <linux/ctype.h> +#include <linux/device.h> +#include <linux/ethtool.h> +#include <linux/init.h> +#include <linux/jiffies.h> +#include <linux/kernel.h> +#include <linux/leds.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/netdevice.h> +#include <linux/mutex.h> +#include <linux/rtnetlink.h> +#include <linux/timer.h> +#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 + * + */ + +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; + u8 duplex; + + bool carrier_link_up; + bool hw_control; +}; + +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_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 (!trigger_data->carrier_link_up) + return; + + if (!__ethtool_get_link_ksettings(trigger_data->net_dev, &cmd)) { + trigger_data->link_speed = cmd.base.speed; + trigger_data->duplex = cmd.base.duplex; + } +} + +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; + + 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; + 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_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); + 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_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))) + return -EINVAL; + + cancel_delayed_work_sync(&trigger_data->work); + + trigger_data->mode = mode; + trigger_data->hw_control = can_hw_control(trigger_data); + + 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(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); + +static struct attribute *netdev_trig_attrs[] = { + &dev_attr_device_name.attr, + &dev_attr_link.attr, + &dev_attr_link_10.attr, + &dev_attr_link_100.attr, + &dev_attr_link_1000.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 +}; +ATTRIBUTE_GROUPS(netdev_trig); + +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 (!(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); + 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_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); + + set_device_name(trigger_data, name, strlen(name)); + trigger_data->hw_control = true; + + 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 <ben.whitten@gmail.com>"); +MODULE_AUTHOR("Oliver Jowett <oliver@opencloud.com>"); +MODULE_DESCRIPTION("Netdev LED trigger"); +MODULE_LICENSE("GPL v2"); |