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1// SPDX-License-Identifier: GPL-2.0
2// Copyright 2017 Ben Whitten <ben.whitten@gmail.com>
3// Copyright 2007 Oliver Jowett <oliver@opencloud.com>
4//
5// LED Kernel Netdev Trigger
6//
7// Toggles the LED to reflect the link and traffic state of a named net device
8//
9// Derived from ledtrig-timer.c which is:
10// Copyright 2005-2006 Openedhand Ltd.
11// Author: Richard Purdie <rpurdie@openedhand.com>
12
13#include <linux/atomic.h>
14#include <linux/ctype.h>
15#include <linux/device.h>
16#include <linux/ethtool.h>
17#include <linux/init.h>
18#include <linux/jiffies.h>
19#include <linux/kernel.h>
20#include <linux/leds.h>
21#include <linux/linkmode.h>
22#include <linux/list.h>
23#include <linux/module.h>
24#include <linux/netdevice.h>
25#include <linux/mutex.h>
26#include <linux/phy.h>
27#include <linux/rtnetlink.h>
28#include <linux/timer.h>
29#include "../leds.h"
30
31#define NETDEV_LED_DEFAULT_INTERVAL 50
32
33/*
34 * Configurable sysfs attributes:
35 *
36 * device_name - network device name to monitor
37 * interval - duration of LED blink, in milliseconds
38 * link - LED's normal state reflects whether the link is up
39 * (has carrier) or not
40 * tx - LED blinks on transmitted data
41 * rx - LED blinks on receive data
42 * tx_err - LED blinks on transmit error
43 * rx_err - LED blinks on receive error
44 *
45 * Note: If the user selects a mode that is not supported by hw, default
46 * behavior is to fall back to software control of the LED. However not every
47 * hw supports software control. LED callbacks brightness_set() and
48 * brightness_set_blocking() are NULL in this case. hw_control_is_supported()
49 * should use available means supported by hw to inform the user that selected
50 * mode isn't supported by hw. This could be switching off the LED or any
51 * hw blink mode. If software control fallback isn't possible, we return
52 * -EOPNOTSUPP to the user, but still store the selected mode. This is needed
53 * in case an intermediate unsupported mode is necessary to switch from one
54 * supported mode to another.
55 */
56
57struct led_netdev_data {
58 struct mutex lock;
59
60 struct delayed_work work;
61 struct notifier_block notifier;
62
63 struct led_classdev *led_cdev;
64 struct net_device *net_dev;
65
66 char device_name[IFNAMSIZ];
67 atomic_t interval;
68 unsigned int last_activity;
69
70 unsigned long mode;
71 int link_speed;
72 __ETHTOOL_DECLARE_LINK_MODE_MASK(supported_link_modes);
73 u8 duplex;
74
75 bool carrier_link_up;
76 bool hw_control;
77};
78
79static const struct attribute_group netdev_trig_link_speed_attrs_group;
80
81static void set_baseline_state(struct led_netdev_data *trigger_data)
82{
83 int current_brightness;
84 struct led_classdev *led_cdev = trigger_data->led_cdev;
85
86 /* Already validated, hw control is possible with the requested mode */
87 if (trigger_data->hw_control) {
88 led_cdev->hw_control_set(led_cdev, trigger_data->mode);
89
90 return;
91 }
92
93 current_brightness = led_cdev->brightness;
94 if (current_brightness)
95 led_cdev->blink_brightness = current_brightness;
96 if (!led_cdev->blink_brightness)
97 led_cdev->blink_brightness = led_cdev->max_brightness;
98
99 if (!trigger_data->carrier_link_up) {
100 led_set_brightness(led_cdev, LED_OFF);
101 } else {
102 bool blink_on = false;
103
104 if (test_bit(TRIGGER_NETDEV_LINK, &trigger_data->mode))
105 blink_on = true;
106
107 if (test_bit(TRIGGER_NETDEV_LINK_10, &trigger_data->mode) &&
108 trigger_data->link_speed == SPEED_10)
109 blink_on = true;
110
111 if (test_bit(TRIGGER_NETDEV_LINK_100, &trigger_data->mode) &&
112 trigger_data->link_speed == SPEED_100)
113 blink_on = true;
114
115 if (test_bit(TRIGGER_NETDEV_LINK_1000, &trigger_data->mode) &&
116 trigger_data->link_speed == SPEED_1000)
117 blink_on = true;
118
119 if (test_bit(TRIGGER_NETDEV_LINK_2500, &trigger_data->mode) &&
120 trigger_data->link_speed == SPEED_2500)
121 blink_on = true;
122
123 if (test_bit(TRIGGER_NETDEV_LINK_5000, &trigger_data->mode) &&
124 trigger_data->link_speed == SPEED_5000)
125 blink_on = true;
126
127 if (test_bit(TRIGGER_NETDEV_LINK_10000, &trigger_data->mode) &&
128 trigger_data->link_speed == SPEED_10000)
129 blink_on = true;
130
131 if (test_bit(TRIGGER_NETDEV_HALF_DUPLEX, &trigger_data->mode) &&
132 trigger_data->duplex == DUPLEX_HALF)
133 blink_on = true;
134
135 if (test_bit(TRIGGER_NETDEV_FULL_DUPLEX, &trigger_data->mode) &&
136 trigger_data->duplex == DUPLEX_FULL)
137 blink_on = true;
138
139 if (blink_on)
140 led_set_brightness(led_cdev,
141 led_cdev->blink_brightness);
142 else
143 led_set_brightness(led_cdev, LED_OFF);
144
145 /* If we are looking for RX/TX start periodically
146 * checking stats
147 */
148 if (test_bit(TRIGGER_NETDEV_TX, &trigger_data->mode) ||
149 test_bit(TRIGGER_NETDEV_RX, &trigger_data->mode) ||
150 test_bit(TRIGGER_NETDEV_TX_ERR, &trigger_data->mode) ||
151 test_bit(TRIGGER_NETDEV_RX_ERR, &trigger_data->mode))
152 schedule_delayed_work(&trigger_data->work, 0);
153 }
154}
155
156static bool supports_hw_control(struct led_classdev *led_cdev)
157{
158 if (!led_cdev->hw_control_get || !led_cdev->hw_control_set ||
159 !led_cdev->hw_control_is_supported)
160 return false;
161
162 return !strcmp(led_cdev->hw_control_trigger, led_cdev->trigger->name);
163}
164
165/*
166 * Validate the configured netdev is the same as the one associated with
167 * the LED driver in hw control.
168 */
169static bool validate_net_dev(struct led_classdev *led_cdev,
170 struct net_device *net_dev)
171{
172 struct device *dev = led_cdev->hw_control_get_device(led_cdev);
173 struct net_device *ndev;
174
175 if (!dev)
176 return false;
177
178 ndev = to_net_dev(dev);
179
180 return ndev == net_dev;
181}
182
183static bool can_hw_control(struct led_netdev_data *trigger_data)
184{
185 unsigned long default_interval = msecs_to_jiffies(NETDEV_LED_DEFAULT_INTERVAL);
186 unsigned int interval = atomic_read(&trigger_data->interval);
187 struct led_classdev *led_cdev = trigger_data->led_cdev;
188 int ret;
189
190 if (!supports_hw_control(led_cdev))
191 return false;
192
193 /*
194 * Interval must be set to the default
195 * value. Any different value is rejected if in hw
196 * control.
197 */
198 if (interval != default_interval)
199 return false;
200
201 /*
202 * net_dev must be set with hw control, otherwise no
203 * blinking can be happening and there is nothing to
204 * offloaded. Additionally, for hw control to be
205 * valid, the configured netdev must be the same as
206 * netdev associated to the LED.
207 */
208 if (!validate_net_dev(led_cdev, trigger_data->net_dev))
209 return false;
210
211 /* Check if the requested mode is supported */
212 ret = led_cdev->hw_control_is_supported(led_cdev, trigger_data->mode);
213 /* Fall back to software blinking if not supported */
214 if (ret == -EOPNOTSUPP)
215 return false;
216 if (ret) {
217 dev_warn(led_cdev->dev,
218 "Current mode check failed with error %d\n", ret);
219 return false;
220 }
221
222 return true;
223}
224
225static void get_device_state(struct led_netdev_data *trigger_data)
226{
227 struct ethtool_link_ksettings cmd;
228
229 trigger_data->carrier_link_up = netif_carrier_ok(trigger_data->net_dev);
230
231 if (__ethtool_get_link_ksettings(trigger_data->net_dev, &cmd))
232 return;
233
234 if (trigger_data->carrier_link_up) {
235 trigger_data->link_speed = cmd.base.speed;
236 trigger_data->duplex = cmd.base.duplex;
237 }
238
239 /*
240 * Have a local copy of the link speed supported to avoid rtnl lock every time
241 * modes are refreshed on any change event
242 */
243 linkmode_copy(trigger_data->supported_link_modes, cmd.link_modes.supported);
244}
245
246static ssize_t device_name_show(struct device *dev,
247 struct device_attribute *attr, char *buf)
248{
249 struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
250 ssize_t len;
251
252 mutex_lock(&trigger_data->lock);
253 len = sprintf(buf, "%s\n", trigger_data->device_name);
254 mutex_unlock(&trigger_data->lock);
255
256 return len;
257}
258
259static int set_device_name(struct led_netdev_data *trigger_data,
260 const char *name, size_t size)
261{
262 if (size >= IFNAMSIZ)
263 return -EINVAL;
264
265 cancel_delayed_work_sync(&trigger_data->work);
266
267 /*
268 * Take RTNL lock before trigger_data lock to prevent potential
269 * deadlock with netdev notifier registration.
270 */
271 rtnl_lock();
272 mutex_lock(&trigger_data->lock);
273
274 if (trigger_data->net_dev) {
275 dev_put(trigger_data->net_dev);
276 trigger_data->net_dev = NULL;
277 }
278
279 memcpy(trigger_data->device_name, name, size);
280 trigger_data->device_name[size] = 0;
281 if (size > 0 && trigger_data->device_name[size - 1] == '\n')
282 trigger_data->device_name[size - 1] = 0;
283
284 if (trigger_data->device_name[0] != 0)
285 trigger_data->net_dev =
286 dev_get_by_name(&init_net, trigger_data->device_name);
287
288 trigger_data->carrier_link_up = false;
289 trigger_data->link_speed = SPEED_UNKNOWN;
290 trigger_data->duplex = DUPLEX_UNKNOWN;
291 if (trigger_data->net_dev)
292 get_device_state(trigger_data);
293
294 trigger_data->last_activity = 0;
295
296 /* Skip if we're called from netdev_trig_activate() and hw_control is true */
297 if (!trigger_data->hw_control || led_get_trigger_data(trigger_data->led_cdev))
298 set_baseline_state(trigger_data);
299
300 mutex_unlock(&trigger_data->lock);
301 rtnl_unlock();
302
303 return 0;
304}
305
306static ssize_t device_name_store(struct device *dev,
307 struct device_attribute *attr, const char *buf,
308 size_t size)
309{
310 struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
311 int ret;
312
313 ret = set_device_name(trigger_data, buf, size);
314
315 if (ret < 0)
316 return ret;
317
318 /* Refresh link_speed visibility */
319 sysfs_update_group(&dev->kobj, &netdev_trig_link_speed_attrs_group);
320
321 return size;
322}
323
324static DEVICE_ATTR_RW(device_name);
325
326static ssize_t netdev_led_attr_show(struct device *dev, char *buf,
327 enum led_trigger_netdev_modes attr)
328{
329 struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
330 int bit;
331
332 switch (attr) {
333 case TRIGGER_NETDEV_LINK:
334 case TRIGGER_NETDEV_LINK_10:
335 case TRIGGER_NETDEV_LINK_100:
336 case TRIGGER_NETDEV_LINK_1000:
337 case TRIGGER_NETDEV_LINK_2500:
338 case TRIGGER_NETDEV_LINK_5000:
339 case TRIGGER_NETDEV_LINK_10000:
340 case TRIGGER_NETDEV_HALF_DUPLEX:
341 case TRIGGER_NETDEV_FULL_DUPLEX:
342 case TRIGGER_NETDEV_TX:
343 case TRIGGER_NETDEV_RX:
344 case TRIGGER_NETDEV_TX_ERR:
345 case TRIGGER_NETDEV_RX_ERR:
346 bit = attr;
347 break;
348 default:
349 return -EINVAL;
350 }
351
352 return sprintf(buf, "%u\n", test_bit(bit, &trigger_data->mode));
353}
354
355static ssize_t netdev_led_attr_store(struct device *dev, const char *buf,
356 size_t size, enum led_trigger_netdev_modes attr)
357{
358 struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
359 struct led_classdev *led_cdev = trigger_data->led_cdev;
360 unsigned long state, mode = trigger_data->mode;
361 int ret;
362 int bit;
363
364 ret = kstrtoul(buf, 0, &state);
365 if (ret)
366 return ret;
367
368 switch (attr) {
369 case TRIGGER_NETDEV_LINK:
370 case TRIGGER_NETDEV_LINK_10:
371 case TRIGGER_NETDEV_LINK_100:
372 case TRIGGER_NETDEV_LINK_1000:
373 case TRIGGER_NETDEV_LINK_2500:
374 case TRIGGER_NETDEV_LINK_5000:
375 case TRIGGER_NETDEV_LINK_10000:
376 case TRIGGER_NETDEV_HALF_DUPLEX:
377 case TRIGGER_NETDEV_FULL_DUPLEX:
378 case TRIGGER_NETDEV_TX:
379 case TRIGGER_NETDEV_RX:
380 case TRIGGER_NETDEV_TX_ERR:
381 case TRIGGER_NETDEV_RX_ERR:
382 bit = attr;
383 break;
384 default:
385 return -EINVAL;
386 }
387
388 if (state)
389 set_bit(bit, &mode);
390 else
391 clear_bit(bit, &mode);
392
393 if (test_bit(TRIGGER_NETDEV_LINK, &mode) &&
394 (test_bit(TRIGGER_NETDEV_LINK_10, &mode) ||
395 test_bit(TRIGGER_NETDEV_LINK_100, &mode) ||
396 test_bit(TRIGGER_NETDEV_LINK_1000, &mode) ||
397 test_bit(TRIGGER_NETDEV_LINK_2500, &mode) ||
398 test_bit(TRIGGER_NETDEV_LINK_5000, &mode) ||
399 test_bit(TRIGGER_NETDEV_LINK_10000, &mode)))
400 return -EINVAL;
401
402 cancel_delayed_work_sync(&trigger_data->work);
403
404 trigger_data->mode = mode;
405 trigger_data->hw_control = can_hw_control(trigger_data);
406
407 if (!led_cdev->brightness_set && !led_cdev->brightness_set_blocking &&
408 !trigger_data->hw_control)
409 return -EOPNOTSUPP;
410
411 set_baseline_state(trigger_data);
412
413 return size;
414}
415
416#define DEFINE_NETDEV_TRIGGER(trigger_name, trigger) \
417 static ssize_t trigger_name##_show(struct device *dev, \
418 struct device_attribute *attr, char *buf) \
419 { \
420 return netdev_led_attr_show(dev, buf, trigger); \
421 } \
422 static ssize_t trigger_name##_store(struct device *dev, \
423 struct device_attribute *attr, const char *buf, size_t size) \
424 { \
425 return netdev_led_attr_store(dev, buf, size, trigger); \
426 } \
427 static DEVICE_ATTR_RW(trigger_name)
428
429DEFINE_NETDEV_TRIGGER(link, TRIGGER_NETDEV_LINK);
430DEFINE_NETDEV_TRIGGER(link_10, TRIGGER_NETDEV_LINK_10);
431DEFINE_NETDEV_TRIGGER(link_100, TRIGGER_NETDEV_LINK_100);
432DEFINE_NETDEV_TRIGGER(link_1000, TRIGGER_NETDEV_LINK_1000);
433DEFINE_NETDEV_TRIGGER(link_2500, TRIGGER_NETDEV_LINK_2500);
434DEFINE_NETDEV_TRIGGER(link_5000, TRIGGER_NETDEV_LINK_5000);
435DEFINE_NETDEV_TRIGGER(link_10000, TRIGGER_NETDEV_LINK_10000);
436DEFINE_NETDEV_TRIGGER(half_duplex, TRIGGER_NETDEV_HALF_DUPLEX);
437DEFINE_NETDEV_TRIGGER(full_duplex, TRIGGER_NETDEV_FULL_DUPLEX);
438DEFINE_NETDEV_TRIGGER(tx, TRIGGER_NETDEV_TX);
439DEFINE_NETDEV_TRIGGER(rx, TRIGGER_NETDEV_RX);
440DEFINE_NETDEV_TRIGGER(tx_err, TRIGGER_NETDEV_TX_ERR);
441DEFINE_NETDEV_TRIGGER(rx_err, TRIGGER_NETDEV_RX_ERR);
442
443static ssize_t interval_show(struct device *dev,
444 struct device_attribute *attr, char *buf)
445{
446 struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
447
448 return sprintf(buf, "%u\n",
449 jiffies_to_msecs(atomic_read(&trigger_data->interval)));
450}
451
452static ssize_t interval_store(struct device *dev,
453 struct device_attribute *attr, const char *buf,
454 size_t size)
455{
456 struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
457 unsigned long value;
458 int ret;
459
460 if (trigger_data->hw_control)
461 return -EINVAL;
462
463 ret = kstrtoul(buf, 0, &value);
464 if (ret)
465 return ret;
466
467 /* impose some basic bounds on the timer interval */
468 if (value >= 5 && value <= 10000) {
469 cancel_delayed_work_sync(&trigger_data->work);
470
471 atomic_set(&trigger_data->interval, msecs_to_jiffies(value));
472 set_baseline_state(trigger_data); /* resets timer */
473 }
474
475 return size;
476}
477
478static DEVICE_ATTR_RW(interval);
479
480static ssize_t offloaded_show(struct device *dev,
481 struct device_attribute *attr, char *buf)
482{
483 struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
484
485 return sprintf(buf, "%d\n", trigger_data->hw_control);
486}
487
488static DEVICE_ATTR_RO(offloaded);
489
490#define CHECK_LINK_MODE_ATTR(link_speed) \
491 do { \
492 if (attr == &dev_attr_link_##link_speed.attr && \
493 link_ksettings.base.speed == SPEED_##link_speed) \
494 return attr->mode; \
495 } while (0)
496
497static umode_t netdev_trig_link_speed_visible(struct kobject *kobj,
498 struct attribute *attr, int n)
499{
500 struct device *dev = kobj_to_dev(kobj);
501 struct led_netdev_data *trigger_data;
502 unsigned long *supported_link_modes;
503 u32 mode;
504
505 trigger_data = led_trigger_get_drvdata(dev);
506 supported_link_modes = trigger_data->supported_link_modes;
507
508 /*
509 * Search in the supported link mode mask a matching supported mode.
510 * Stop at the first matching entry as we care only to check if a particular
511 * speed is supported and not the kind.
512 */
513 for_each_set_bit(mode, supported_link_modes, __ETHTOOL_LINK_MODE_MASK_NBITS) {
514 struct ethtool_link_ksettings link_ksettings;
515
516 ethtool_params_from_link_mode(&link_ksettings, mode);
517
518 CHECK_LINK_MODE_ATTR(10);
519 CHECK_LINK_MODE_ATTR(100);
520 CHECK_LINK_MODE_ATTR(1000);
521 CHECK_LINK_MODE_ATTR(2500);
522 CHECK_LINK_MODE_ATTR(5000);
523 CHECK_LINK_MODE_ATTR(10000);
524 }
525
526 return 0;
527}
528
529static struct attribute *netdev_trig_link_speed_attrs[] = {
530 &dev_attr_link_10.attr,
531 &dev_attr_link_100.attr,
532 &dev_attr_link_1000.attr,
533 &dev_attr_link_2500.attr,
534 &dev_attr_link_5000.attr,
535 &dev_attr_link_10000.attr,
536 NULL
537};
538
539static const struct attribute_group netdev_trig_link_speed_attrs_group = {
540 .attrs = netdev_trig_link_speed_attrs,
541 .is_visible = netdev_trig_link_speed_visible,
542};
543
544static struct attribute *netdev_trig_attrs[] = {
545 &dev_attr_device_name.attr,
546 &dev_attr_link.attr,
547 &dev_attr_full_duplex.attr,
548 &dev_attr_half_duplex.attr,
549 &dev_attr_rx.attr,
550 &dev_attr_tx.attr,
551 &dev_attr_rx_err.attr,
552 &dev_attr_tx_err.attr,
553 &dev_attr_interval.attr,
554 &dev_attr_offloaded.attr,
555 NULL
556};
557
558static const struct attribute_group netdev_trig_attrs_group = {
559 .attrs = netdev_trig_attrs,
560};
561
562static const struct attribute_group *netdev_trig_groups[] = {
563 &netdev_trig_attrs_group,
564 &netdev_trig_link_speed_attrs_group,
565 NULL,
566};
567
568static int netdev_trig_notify(struct notifier_block *nb,
569 unsigned long evt, void *dv)
570{
571 struct net_device *dev =
572 netdev_notifier_info_to_dev((struct netdev_notifier_info *)dv);
573 struct led_netdev_data *trigger_data =
574 container_of(nb, struct led_netdev_data, notifier);
575 struct led_classdev *led_cdev = trigger_data->led_cdev;
576
577 if (evt != NETDEV_UP && evt != NETDEV_DOWN && evt != NETDEV_CHANGE
578 && evt != NETDEV_REGISTER && evt != NETDEV_UNREGISTER
579 && evt != NETDEV_CHANGENAME)
580 return NOTIFY_DONE;
581
582 if (!(dev == trigger_data->net_dev ||
583 (evt == NETDEV_CHANGENAME && !strcmp(dev->name, trigger_data->device_name)) ||
584 (evt == NETDEV_REGISTER && !strcmp(dev->name, trigger_data->device_name))))
585 return NOTIFY_DONE;
586
587 cancel_delayed_work_sync(&trigger_data->work);
588
589 mutex_lock(&trigger_data->lock);
590
591 trigger_data->carrier_link_up = false;
592 trigger_data->link_speed = SPEED_UNKNOWN;
593 trigger_data->duplex = DUPLEX_UNKNOWN;
594 switch (evt) {
595 case NETDEV_CHANGENAME:
596 case NETDEV_REGISTER:
597 dev_put(trigger_data->net_dev);
598 dev_hold(dev);
599 trigger_data->net_dev = dev;
600 if (evt == NETDEV_CHANGENAME)
601 get_device_state(trigger_data);
602 break;
603 case NETDEV_UNREGISTER:
604 dev_put(trigger_data->net_dev);
605 trigger_data->net_dev = NULL;
606 break;
607 case NETDEV_UP:
608 case NETDEV_CHANGE:
609 get_device_state(trigger_data);
610 /* Refresh link_speed visibility */
611 if (evt == NETDEV_CHANGE)
612 sysfs_update_group(&led_cdev->dev->kobj,
613 &netdev_trig_link_speed_attrs_group);
614 break;
615 }
616
617 set_baseline_state(trigger_data);
618
619 mutex_unlock(&trigger_data->lock);
620
621 return NOTIFY_DONE;
622}
623
624/* here's the real work! */
625static void netdev_trig_work(struct work_struct *work)
626{
627 struct led_netdev_data *trigger_data =
628 container_of(work, struct led_netdev_data, work.work);
629 struct rtnl_link_stats64 *dev_stats;
630 unsigned int new_activity;
631 struct rtnl_link_stats64 temp;
632 unsigned long interval;
633 int invert;
634
635 /* If we dont have a device, insure we are off */
636 if (!trigger_data->net_dev) {
637 led_set_brightness(trigger_data->led_cdev, LED_OFF);
638 return;
639 }
640
641 /* If we are not looking for RX/TX then return */
642 if (!test_bit(TRIGGER_NETDEV_TX, &trigger_data->mode) &&
643 !test_bit(TRIGGER_NETDEV_RX, &trigger_data->mode) &&
644 !test_bit(TRIGGER_NETDEV_TX_ERR, &trigger_data->mode) &&
645 !test_bit(TRIGGER_NETDEV_RX_ERR, &trigger_data->mode))
646 return;
647
648 dev_stats = dev_get_stats(trigger_data->net_dev, &temp);
649 new_activity =
650 (test_bit(TRIGGER_NETDEV_TX, &trigger_data->mode) ?
651 dev_stats->tx_packets : 0) +
652 (test_bit(TRIGGER_NETDEV_RX, &trigger_data->mode) ?
653 dev_stats->rx_packets : 0) +
654 (test_bit(TRIGGER_NETDEV_TX_ERR, &trigger_data->mode) ?
655 dev_stats->tx_errors : 0) +
656 (test_bit(TRIGGER_NETDEV_RX_ERR, &trigger_data->mode) ?
657 dev_stats->rx_errors : 0);
658
659 if (trigger_data->last_activity != new_activity) {
660 led_stop_software_blink(trigger_data->led_cdev);
661
662 invert = test_bit(TRIGGER_NETDEV_LINK, &trigger_data->mode) ||
663 test_bit(TRIGGER_NETDEV_LINK_10, &trigger_data->mode) ||
664 test_bit(TRIGGER_NETDEV_LINK_100, &trigger_data->mode) ||
665 test_bit(TRIGGER_NETDEV_LINK_1000, &trigger_data->mode) ||
666 test_bit(TRIGGER_NETDEV_LINK_2500, &trigger_data->mode) ||
667 test_bit(TRIGGER_NETDEV_LINK_5000, &trigger_data->mode) ||
668 test_bit(TRIGGER_NETDEV_LINK_10000, &trigger_data->mode) ||
669 test_bit(TRIGGER_NETDEV_HALF_DUPLEX, &trigger_data->mode) ||
670 test_bit(TRIGGER_NETDEV_FULL_DUPLEX, &trigger_data->mode);
671 interval = jiffies_to_msecs(
672 atomic_read(&trigger_data->interval));
673 /* base state is ON (link present) */
674 led_blink_set_oneshot(trigger_data->led_cdev,
675 &interval,
676 &interval,
677 invert);
678 trigger_data->last_activity = new_activity;
679 }
680
681 schedule_delayed_work(&trigger_data->work,
682 (atomic_read(&trigger_data->interval)*2));
683}
684
685static int netdev_trig_activate(struct led_classdev *led_cdev)
686{
687 struct led_netdev_data *trigger_data;
688 unsigned long mode = 0;
689 struct device *dev;
690 int rc;
691
692 trigger_data = kzalloc(sizeof(struct led_netdev_data), GFP_KERNEL);
693 if (!trigger_data)
694 return -ENOMEM;
695
696 mutex_init(&trigger_data->lock);
697
698 trigger_data->notifier.notifier_call = netdev_trig_notify;
699 trigger_data->notifier.priority = 10;
700
701 INIT_DELAYED_WORK(&trigger_data->work, netdev_trig_work);
702
703 trigger_data->led_cdev = led_cdev;
704 trigger_data->net_dev = NULL;
705 trigger_data->device_name[0] = 0;
706
707 trigger_data->mode = 0;
708 atomic_set(&trigger_data->interval, msecs_to_jiffies(NETDEV_LED_DEFAULT_INTERVAL));
709 trigger_data->last_activity = 0;
710
711 /* Check if hw control is active by default on the LED.
712 * Init already enabled mode in hw control.
713 */
714 if (supports_hw_control(led_cdev)) {
715 dev = led_cdev->hw_control_get_device(led_cdev);
716 if (dev) {
717 const char *name = dev_name(dev);
718
719 trigger_data->hw_control = true;
720 set_device_name(trigger_data, name, strlen(name));
721
722 rc = led_cdev->hw_control_get(led_cdev, &mode);
723 if (!rc)
724 trigger_data->mode = mode;
725 }
726 }
727
728 led_set_trigger_data(led_cdev, trigger_data);
729
730 rc = register_netdevice_notifier(&trigger_data->notifier);
731 if (rc)
732 kfree(trigger_data);
733
734 return rc;
735}
736
737static void netdev_trig_deactivate(struct led_classdev *led_cdev)
738{
739 struct led_netdev_data *trigger_data = led_get_trigger_data(led_cdev);
740
741 unregister_netdevice_notifier(&trigger_data->notifier);
742
743 cancel_delayed_work_sync(&trigger_data->work);
744
745 dev_put(trigger_data->net_dev);
746
747 kfree(trigger_data);
748}
749
750static struct led_trigger netdev_led_trigger = {
751 .name = "netdev",
752 .activate = netdev_trig_activate,
753 .deactivate = netdev_trig_deactivate,
754 .groups = netdev_trig_groups,
755};
756
757module_led_trigger(netdev_led_trigger);
758
759MODULE_AUTHOR("Ben Whitten <ben.whitten@gmail.com>");
760MODULE_AUTHOR("Oliver Jowett <oliver@opencloud.com>");
761MODULE_DESCRIPTION("Netdev LED trigger");
762MODULE_LICENSE("GPL v2");
763MODULE_ALIAS("ledtrig:netdev");
1// SPDX-License-Identifier: GPL-2.0
2// Copyright 2017 Ben Whitten <ben.whitten@gmail.com>
3// Copyright 2007 Oliver Jowett <oliver@opencloud.com>
4//
5// LED Kernel Netdev Trigger
6//
7// Toggles the LED to reflect the link and traffic state of a named net device
8//
9// Derived from ledtrig-timer.c which is:
10// Copyright 2005-2006 Openedhand Ltd.
11// Author: Richard Purdie <rpurdie@openedhand.com>
12
13#include <linux/atomic.h>
14#include <linux/ctype.h>
15#include <linux/device.h>
16#include <linux/init.h>
17#include <linux/jiffies.h>
18#include <linux/kernel.h>
19#include <linux/leds.h>
20#include <linux/list.h>
21#include <linux/module.h>
22#include <linux/netdevice.h>
23#include <linux/spinlock.h>
24#include <linux/timer.h>
25#include "../leds.h"
26
27/*
28 * Configurable sysfs attributes:
29 *
30 * device_name - network device name to monitor
31 * interval - duration of LED blink, in milliseconds
32 * link - LED's normal state reflects whether the link is up
33 * (has carrier) or not
34 * tx - LED blinks on transmitted data
35 * rx - LED blinks on receive data
36 *
37 */
38
39struct led_netdev_data {
40 spinlock_t lock;
41
42 struct delayed_work work;
43 struct notifier_block notifier;
44
45 struct led_classdev *led_cdev;
46 struct net_device *net_dev;
47
48 char device_name[IFNAMSIZ];
49 atomic_t interval;
50 unsigned int last_activity;
51
52 unsigned long mode;
53#define NETDEV_LED_LINK 0
54#define NETDEV_LED_TX 1
55#define NETDEV_LED_RX 2
56#define NETDEV_LED_MODE_LINKUP 3
57};
58
59enum netdev_led_attr {
60 NETDEV_ATTR_LINK,
61 NETDEV_ATTR_TX,
62 NETDEV_ATTR_RX
63};
64
65static void set_baseline_state(struct led_netdev_data *trigger_data)
66{
67 int current_brightness;
68 struct led_classdev *led_cdev = trigger_data->led_cdev;
69
70 current_brightness = led_cdev->brightness;
71 if (current_brightness)
72 led_cdev->blink_brightness = current_brightness;
73 if (!led_cdev->blink_brightness)
74 led_cdev->blink_brightness = led_cdev->max_brightness;
75
76 if (!test_bit(NETDEV_LED_MODE_LINKUP, &trigger_data->mode))
77 led_set_brightness(led_cdev, LED_OFF);
78 else {
79 if (test_bit(NETDEV_LED_LINK, &trigger_data->mode))
80 led_set_brightness(led_cdev,
81 led_cdev->blink_brightness);
82 else
83 led_set_brightness(led_cdev, LED_OFF);
84
85 /* If we are looking for RX/TX start periodically
86 * checking stats
87 */
88 if (test_bit(NETDEV_LED_TX, &trigger_data->mode) ||
89 test_bit(NETDEV_LED_RX, &trigger_data->mode))
90 schedule_delayed_work(&trigger_data->work, 0);
91 }
92}
93
94static ssize_t device_name_show(struct device *dev,
95 struct device_attribute *attr, char *buf)
96{
97 struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
98 ssize_t len;
99
100 spin_lock_bh(&trigger_data->lock);
101 len = sprintf(buf, "%s\n", trigger_data->device_name);
102 spin_unlock_bh(&trigger_data->lock);
103
104 return len;
105}
106
107static ssize_t device_name_store(struct device *dev,
108 struct device_attribute *attr, const char *buf,
109 size_t size)
110{
111 struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
112
113 if (size >= IFNAMSIZ)
114 return -EINVAL;
115
116 cancel_delayed_work_sync(&trigger_data->work);
117
118 spin_lock_bh(&trigger_data->lock);
119
120 if (trigger_data->net_dev) {
121 dev_put(trigger_data->net_dev);
122 trigger_data->net_dev = NULL;
123 }
124
125 memcpy(trigger_data->device_name, buf, size);
126 trigger_data->device_name[size] = 0;
127 if (size > 0 && trigger_data->device_name[size - 1] == '\n')
128 trigger_data->device_name[size - 1] = 0;
129
130 if (trigger_data->device_name[0] != 0)
131 trigger_data->net_dev =
132 dev_get_by_name(&init_net, trigger_data->device_name);
133
134 clear_bit(NETDEV_LED_MODE_LINKUP, &trigger_data->mode);
135 if (trigger_data->net_dev != NULL)
136 if (netif_carrier_ok(trigger_data->net_dev))
137 set_bit(NETDEV_LED_MODE_LINKUP, &trigger_data->mode);
138
139 trigger_data->last_activity = 0;
140
141 set_baseline_state(trigger_data);
142 spin_unlock_bh(&trigger_data->lock);
143
144 return size;
145}
146
147static DEVICE_ATTR_RW(device_name);
148
149static ssize_t netdev_led_attr_show(struct device *dev, char *buf,
150 enum netdev_led_attr attr)
151{
152 struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
153 int bit;
154
155 switch (attr) {
156 case NETDEV_ATTR_LINK:
157 bit = NETDEV_LED_LINK;
158 break;
159 case NETDEV_ATTR_TX:
160 bit = NETDEV_LED_TX;
161 break;
162 case NETDEV_ATTR_RX:
163 bit = NETDEV_LED_RX;
164 break;
165 default:
166 return -EINVAL;
167 }
168
169 return sprintf(buf, "%u\n", test_bit(bit, &trigger_data->mode));
170}
171
172static ssize_t netdev_led_attr_store(struct device *dev, const char *buf,
173 size_t size, enum netdev_led_attr attr)
174{
175 struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
176 unsigned long state;
177 int ret;
178 int bit;
179
180 ret = kstrtoul(buf, 0, &state);
181 if (ret)
182 return ret;
183
184 switch (attr) {
185 case NETDEV_ATTR_LINK:
186 bit = NETDEV_LED_LINK;
187 break;
188 case NETDEV_ATTR_TX:
189 bit = NETDEV_LED_TX;
190 break;
191 case NETDEV_ATTR_RX:
192 bit = NETDEV_LED_RX;
193 break;
194 default:
195 return -EINVAL;
196 }
197
198 cancel_delayed_work_sync(&trigger_data->work);
199
200 if (state)
201 set_bit(bit, &trigger_data->mode);
202 else
203 clear_bit(bit, &trigger_data->mode);
204
205 set_baseline_state(trigger_data);
206
207 return size;
208}
209
210static ssize_t link_show(struct device *dev,
211 struct device_attribute *attr, char *buf)
212{
213 return netdev_led_attr_show(dev, buf, NETDEV_ATTR_LINK);
214}
215
216static ssize_t link_store(struct device *dev,
217 struct device_attribute *attr, const char *buf, size_t size)
218{
219 return netdev_led_attr_store(dev, buf, size, NETDEV_ATTR_LINK);
220}
221
222static DEVICE_ATTR_RW(link);
223
224static ssize_t tx_show(struct device *dev,
225 struct device_attribute *attr, char *buf)
226{
227 return netdev_led_attr_show(dev, buf, NETDEV_ATTR_TX);
228}
229
230static ssize_t tx_store(struct device *dev,
231 struct device_attribute *attr, const char *buf, size_t size)
232{
233 return netdev_led_attr_store(dev, buf, size, NETDEV_ATTR_TX);
234}
235
236static DEVICE_ATTR_RW(tx);
237
238static ssize_t rx_show(struct device *dev,
239 struct device_attribute *attr, char *buf)
240{
241 return netdev_led_attr_show(dev, buf, NETDEV_ATTR_RX);
242}
243
244static ssize_t rx_store(struct device *dev,
245 struct device_attribute *attr, const char *buf, size_t size)
246{
247 return netdev_led_attr_store(dev, buf, size, NETDEV_ATTR_RX);
248}
249
250static DEVICE_ATTR_RW(rx);
251
252static ssize_t interval_show(struct device *dev,
253 struct device_attribute *attr, char *buf)
254{
255 struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
256
257 return sprintf(buf, "%u\n",
258 jiffies_to_msecs(atomic_read(&trigger_data->interval)));
259}
260
261static ssize_t interval_store(struct device *dev,
262 struct device_attribute *attr, const char *buf,
263 size_t size)
264{
265 struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
266 unsigned long value;
267 int ret;
268
269 ret = kstrtoul(buf, 0, &value);
270 if (ret)
271 return ret;
272
273 /* impose some basic bounds on the timer interval */
274 if (value >= 5 && value <= 10000) {
275 cancel_delayed_work_sync(&trigger_data->work);
276
277 atomic_set(&trigger_data->interval, msecs_to_jiffies(value));
278 set_baseline_state(trigger_data); /* resets timer */
279 }
280
281 return size;
282}
283
284static DEVICE_ATTR_RW(interval);
285
286static struct attribute *netdev_trig_attrs[] = {
287 &dev_attr_device_name.attr,
288 &dev_attr_link.attr,
289 &dev_attr_rx.attr,
290 &dev_attr_tx.attr,
291 &dev_attr_interval.attr,
292 NULL
293};
294ATTRIBUTE_GROUPS(netdev_trig);
295
296static int netdev_trig_notify(struct notifier_block *nb,
297 unsigned long evt, void *dv)
298{
299 struct net_device *dev =
300 netdev_notifier_info_to_dev((struct netdev_notifier_info *)dv);
301 struct led_netdev_data *trigger_data =
302 container_of(nb, struct led_netdev_data, notifier);
303
304 if (evt != NETDEV_UP && evt != NETDEV_DOWN && evt != NETDEV_CHANGE
305 && evt != NETDEV_REGISTER && evt != NETDEV_UNREGISTER
306 && evt != NETDEV_CHANGENAME)
307 return NOTIFY_DONE;
308
309 if (!(dev == trigger_data->net_dev ||
310 (evt == NETDEV_CHANGENAME && !strcmp(dev->name, trigger_data->device_name)) ||
311 (evt == NETDEV_REGISTER && !strcmp(dev->name, trigger_data->device_name))))
312 return NOTIFY_DONE;
313
314 cancel_delayed_work_sync(&trigger_data->work);
315
316 spin_lock_bh(&trigger_data->lock);
317
318 clear_bit(NETDEV_LED_MODE_LINKUP, &trigger_data->mode);
319 switch (evt) {
320 case NETDEV_CHANGENAME:
321 case NETDEV_REGISTER:
322 if (trigger_data->net_dev)
323 dev_put(trigger_data->net_dev);
324 dev_hold(dev);
325 trigger_data->net_dev = dev;
326 break;
327 case NETDEV_UNREGISTER:
328 dev_put(trigger_data->net_dev);
329 trigger_data->net_dev = NULL;
330 break;
331 case NETDEV_UP:
332 case NETDEV_CHANGE:
333 if (netif_carrier_ok(dev))
334 set_bit(NETDEV_LED_MODE_LINKUP, &trigger_data->mode);
335 break;
336 }
337
338 set_baseline_state(trigger_data);
339
340 spin_unlock_bh(&trigger_data->lock);
341
342 return NOTIFY_DONE;
343}
344
345/* here's the real work! */
346static void netdev_trig_work(struct work_struct *work)
347{
348 struct led_netdev_data *trigger_data =
349 container_of(work, struct led_netdev_data, work.work);
350 struct rtnl_link_stats64 *dev_stats;
351 unsigned int new_activity;
352 struct rtnl_link_stats64 temp;
353 unsigned long interval;
354 int invert;
355
356 /* If we dont have a device, insure we are off */
357 if (!trigger_data->net_dev) {
358 led_set_brightness(trigger_data->led_cdev, LED_OFF);
359 return;
360 }
361
362 /* If we are not looking for RX/TX then return */
363 if (!test_bit(NETDEV_LED_TX, &trigger_data->mode) &&
364 !test_bit(NETDEV_LED_RX, &trigger_data->mode))
365 return;
366
367 dev_stats = dev_get_stats(trigger_data->net_dev, &temp);
368 new_activity =
369 (test_bit(NETDEV_LED_TX, &trigger_data->mode) ?
370 dev_stats->tx_packets : 0) +
371 (test_bit(NETDEV_LED_RX, &trigger_data->mode) ?
372 dev_stats->rx_packets : 0);
373
374 if (trigger_data->last_activity != new_activity) {
375 led_stop_software_blink(trigger_data->led_cdev);
376
377 invert = test_bit(NETDEV_LED_LINK, &trigger_data->mode);
378 interval = jiffies_to_msecs(
379 atomic_read(&trigger_data->interval));
380 /* base state is ON (link present) */
381 led_blink_set_oneshot(trigger_data->led_cdev,
382 &interval,
383 &interval,
384 invert);
385 trigger_data->last_activity = new_activity;
386 }
387
388 schedule_delayed_work(&trigger_data->work,
389 (atomic_read(&trigger_data->interval)*2));
390}
391
392static int netdev_trig_activate(struct led_classdev *led_cdev)
393{
394 struct led_netdev_data *trigger_data;
395 int rc;
396
397 trigger_data = kzalloc(sizeof(struct led_netdev_data), GFP_KERNEL);
398 if (!trigger_data)
399 return -ENOMEM;
400
401 spin_lock_init(&trigger_data->lock);
402
403 trigger_data->notifier.notifier_call = netdev_trig_notify;
404 trigger_data->notifier.priority = 10;
405
406 INIT_DELAYED_WORK(&trigger_data->work, netdev_trig_work);
407
408 trigger_data->led_cdev = led_cdev;
409 trigger_data->net_dev = NULL;
410 trigger_data->device_name[0] = 0;
411
412 trigger_data->mode = 0;
413 atomic_set(&trigger_data->interval, msecs_to_jiffies(50));
414 trigger_data->last_activity = 0;
415
416 led_set_trigger_data(led_cdev, trigger_data);
417
418 rc = register_netdevice_notifier(&trigger_data->notifier);
419 if (rc)
420 kfree(trigger_data);
421
422 return rc;
423}
424
425static void netdev_trig_deactivate(struct led_classdev *led_cdev)
426{
427 struct led_netdev_data *trigger_data = led_get_trigger_data(led_cdev);
428
429 unregister_netdevice_notifier(&trigger_data->notifier);
430
431 cancel_delayed_work_sync(&trigger_data->work);
432
433 if (trigger_data->net_dev)
434 dev_put(trigger_data->net_dev);
435
436 kfree(trigger_data);
437}
438
439static struct led_trigger netdev_led_trigger = {
440 .name = "netdev",
441 .activate = netdev_trig_activate,
442 .deactivate = netdev_trig_deactivate,
443 .groups = netdev_trig_groups,
444};
445
446static int __init netdev_trig_init(void)
447{
448 return led_trigger_register(&netdev_led_trigger);
449}
450
451static void __exit netdev_trig_exit(void)
452{
453 led_trigger_unregister(&netdev_led_trigger);
454}
455
456module_init(netdev_trig_init);
457module_exit(netdev_trig_exit);
458
459MODULE_AUTHOR("Ben Whitten <ben.whitten@gmail.com>");
460MODULE_AUTHOR("Oliver Jowett <oliver@opencloud.com>");
461MODULE_DESCRIPTION("Netdev LED trigger");
462MODULE_LICENSE("GPL v2");