blob: 8e5475819590e056142dae6ac1dd8c0dbe186d84 [file] [log] [blame]
// 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
*
* 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;
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_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 (!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_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);
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_link_2500.attr,
&dev_attr_link_5000.attr,
&dev_attr_link_10000.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_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);
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");