xref: /linux/drivers/leds/trigger/ledtrig-netdev.c (revision 1b78070aaef63512688aebfbc82365ef9d6660f1)
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 <net/netdev_lock.h>
30 #include "../leds.h"
31 
32 #define NETDEV_LED_DEFAULT_INTERVAL	50
33 
34 /*
35  * Configurable sysfs attributes:
36  *
37  * device_name - network device name to monitor
38  * interval - duration of LED blink, in milliseconds
39  * link -  LED's normal state reflects whether the link is up
40  *         (has carrier) or not
41  * tx -  LED blinks on transmitted data
42  * rx -  LED blinks on receive data
43  * tx_err -  LED blinks on transmit error
44  * rx_err -  LED blinks on receive error
45  *
46  * Note: If the user selects a mode that is not supported by hw, default
47  * behavior is to fall back to software control of the LED. However not every
48  * hw supports software control. LED callbacks brightness_set() and
49  * brightness_set_blocking() are NULL in this case. hw_control_is_supported()
50  * should use available means supported by hw to inform the user that selected
51  * mode isn't supported by hw. This could be switching off the LED or any
52  * hw blink mode. If software control fallback isn't possible, we return
53  * -EOPNOTSUPP to the user, but still store the selected mode. This is needed
54  * in case an intermediate unsupported mode is necessary to switch from one
55  * supported mode to another.
56  */
57 
58 struct led_netdev_data {
59 	struct mutex lock;
60 
61 	struct delayed_work work;
62 	struct notifier_block notifier;
63 
64 	struct led_classdev *led_cdev;
65 	struct net_device *net_dev;
66 
67 	char device_name[IFNAMSIZ];
68 	atomic_t interval;
69 	unsigned int last_activity;
70 
71 	unsigned long mode;
72 	int link_speed;
73 	__ETHTOOL_DECLARE_LINK_MODE_MASK(supported_link_modes);
74 	u8 duplex;
75 
76 	bool carrier_link_up;
77 	bool hw_control;
78 };
79 
80 static const struct attribute_group netdev_trig_link_speed_attrs_group;
81 
82 static void set_baseline_state(struct led_netdev_data *trigger_data)
83 {
84 	int current_brightness;
85 	struct led_classdev *led_cdev = trigger_data->led_cdev;
86 
87 	/* Already validated, hw control is possible with the requested mode */
88 	if (trigger_data->hw_control) {
89 		led_cdev->hw_control_set(led_cdev, trigger_data->mode);
90 
91 		return;
92 	}
93 
94 	current_brightness = led_cdev->brightness;
95 	if (current_brightness)
96 		led_cdev->blink_brightness = current_brightness;
97 	if (!led_cdev->blink_brightness)
98 		led_cdev->blink_brightness = led_cdev->max_brightness;
99 
100 	if (!trigger_data->carrier_link_up) {
101 		led_set_brightness(led_cdev, LED_OFF);
102 	} else {
103 		bool blink_on = false;
104 
105 		if (test_bit(TRIGGER_NETDEV_LINK, &trigger_data->mode))
106 			blink_on = true;
107 
108 		if (test_bit(TRIGGER_NETDEV_LINK_10, &trigger_data->mode) &&
109 		    trigger_data->link_speed == SPEED_10)
110 			blink_on = true;
111 
112 		if (test_bit(TRIGGER_NETDEV_LINK_100, &trigger_data->mode) &&
113 		    trigger_data->link_speed == SPEED_100)
114 			blink_on = true;
115 
116 		if (test_bit(TRIGGER_NETDEV_LINK_1000, &trigger_data->mode) &&
117 		    trigger_data->link_speed == SPEED_1000)
118 			blink_on = true;
119 
120 		if (test_bit(TRIGGER_NETDEV_LINK_2500, &trigger_data->mode) &&
121 		    trigger_data->link_speed == SPEED_2500)
122 			blink_on = true;
123 
124 		if (test_bit(TRIGGER_NETDEV_LINK_5000, &trigger_data->mode) &&
125 		    trigger_data->link_speed == SPEED_5000)
126 			blink_on = true;
127 
128 		if (test_bit(TRIGGER_NETDEV_LINK_10000, &trigger_data->mode) &&
129 		    trigger_data->link_speed == SPEED_10000)
130 			blink_on = true;
131 
132 		if (test_bit(TRIGGER_NETDEV_LINK_25000, &trigger_data->mode) &&
133 		    trigger_data->link_speed == SPEED_25000)
134 			blink_on = true;
135 
136 		if (test_bit(TRIGGER_NETDEV_LINK_40000, &trigger_data->mode) &&
137 		    trigger_data->link_speed == SPEED_40000)
138 			blink_on = true;
139 
140 		if (test_bit(TRIGGER_NETDEV_LINK_50000, &trigger_data->mode) &&
141 		    trigger_data->link_speed == SPEED_50000)
142 			blink_on = true;
143 
144 		if (test_bit(TRIGGER_NETDEV_LINK_100000, &trigger_data->mode) &&
145 		    trigger_data->link_speed == SPEED_100000)
146 			blink_on = true;
147 
148 		if (test_bit(TRIGGER_NETDEV_HALF_DUPLEX, &trigger_data->mode) &&
149 		    trigger_data->duplex == DUPLEX_HALF)
150 			blink_on = true;
151 
152 		if (test_bit(TRIGGER_NETDEV_FULL_DUPLEX, &trigger_data->mode) &&
153 		    trigger_data->duplex == DUPLEX_FULL)
154 			blink_on = true;
155 
156 		if (blink_on)
157 			led_set_brightness(led_cdev,
158 					   led_cdev->blink_brightness);
159 		else
160 			led_set_brightness(led_cdev, LED_OFF);
161 
162 		/* If we are looking for RX/TX start periodically
163 		 * checking stats
164 		 */
165 		if (test_bit(TRIGGER_NETDEV_TX, &trigger_data->mode) ||
166 		    test_bit(TRIGGER_NETDEV_RX, &trigger_data->mode) ||
167 		    test_bit(TRIGGER_NETDEV_TX_ERR, &trigger_data->mode) ||
168 		    test_bit(TRIGGER_NETDEV_RX_ERR, &trigger_data->mode))
169 			schedule_delayed_work(&trigger_data->work, 0);
170 	}
171 }
172 
173 static bool supports_hw_control(struct led_classdev *led_cdev)
174 {
175 	if (!led_cdev->hw_control_get || !led_cdev->hw_control_set ||
176 	    !led_cdev->hw_control_is_supported)
177 		return false;
178 
179 	return !strcmp(led_cdev->hw_control_trigger, led_cdev->trigger->name);
180 }
181 
182 /*
183  * Validate the configured netdev is the same as the one associated with
184  * the LED driver in hw control.
185  */
186 static bool validate_net_dev(struct led_classdev *led_cdev,
187 			     struct net_device *net_dev)
188 {
189 	struct device *dev = led_cdev->hw_control_get_device(led_cdev);
190 	struct net_device *ndev;
191 
192 	if (!dev)
193 		return false;
194 
195 	ndev = to_net_dev(dev);
196 
197 	return ndev == net_dev;
198 }
199 
200 static bool can_hw_control(struct led_netdev_data *trigger_data)
201 {
202 	unsigned long default_interval = msecs_to_jiffies(NETDEV_LED_DEFAULT_INTERVAL);
203 	unsigned int interval = atomic_read(&trigger_data->interval);
204 	struct led_classdev *led_cdev = trigger_data->led_cdev;
205 	int ret;
206 
207 	if (!supports_hw_control(led_cdev))
208 		return false;
209 
210 	/*
211 	 * Interval must be set to the default
212 	 * value. Any different value is rejected if in hw
213 	 * control.
214 	 */
215 	if (interval != default_interval)
216 		return false;
217 
218 	/*
219 	 * net_dev must be set with hw control, otherwise no
220 	 * blinking can be happening and there is nothing to
221 	 * offloaded. Additionally, for hw control to be
222 	 * valid, the configured netdev must be the same as
223 	 * netdev associated to the LED.
224 	 */
225 	if (!validate_net_dev(led_cdev, trigger_data->net_dev))
226 		return false;
227 
228 	/* Check if the requested mode is supported */
229 	ret = led_cdev->hw_control_is_supported(led_cdev, trigger_data->mode);
230 	/* Fall back to software blinking if not supported */
231 	if (ret == -EOPNOTSUPP)
232 		return false;
233 	if (ret) {
234 		dev_warn(led_cdev->dev,
235 			 "Current mode check failed with error %d\n", ret);
236 		return false;
237 	}
238 
239 	return true;
240 }
241 
242 static void get_device_state(struct led_netdev_data *trigger_data)
243 {
244 	struct ethtool_link_ksettings cmd;
245 
246 	trigger_data->carrier_link_up = netif_carrier_ok(trigger_data->net_dev);
247 
248 	if (netif_get_link_ksettings(trigger_data->net_dev, &cmd))
249 		return;
250 
251 	if (trigger_data->carrier_link_up) {
252 		trigger_data->link_speed = cmd.base.speed;
253 		trigger_data->duplex = cmd.base.duplex;
254 	}
255 
256 	/*
257 	 * Have a local copy of the link speed supported to avoid rtnl lock every time
258 	 * modes are refreshed on any change event
259 	 */
260 	linkmode_copy(trigger_data->supported_link_modes, cmd.link_modes.supported);
261 }
262 
263 static ssize_t device_name_show(struct device *dev,
264 				struct device_attribute *attr, char *buf)
265 {
266 	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
267 	ssize_t len;
268 
269 	mutex_lock(&trigger_data->lock);
270 	len = sprintf(buf, "%s\n", trigger_data->device_name);
271 	mutex_unlock(&trigger_data->lock);
272 
273 	return len;
274 }
275 
276 static int set_device_name(struct led_netdev_data *trigger_data,
277 			   const char *name, size_t size)
278 {
279 	struct net_device *new_dev = NULL;
280 	char device_name[IFNAMSIZ];
281 
282 	if (size >= IFNAMSIZ)
283 		return -EINVAL;
284 
285 	cancel_delayed_work_sync(&trigger_data->work);
286 
287 	memcpy(device_name, name, size);
288 	device_name[size] = 0;
289 	if (size > 0 && device_name[size - 1] == '\n')
290 		device_name[size - 1] = 0;
291 
292 	/*
293 	 * Lock order: rtnl_lock -> netdev instance lock -> trigger_data lock.
294 	 */
295 	rtnl_lock();
296 	if (device_name[0]) {
297 		new_dev = dev_get_by_name(&init_net, device_name);
298 		if (new_dev)
299 			netdev_lock_ops(new_dev);
300 	}
301 	mutex_lock(&trigger_data->lock);
302 
303 	dev_put(trigger_data->net_dev);
304 	trigger_data->net_dev = new_dev;
305 	strscpy(trigger_data->device_name, device_name);
306 
307 	trigger_data->carrier_link_up = false;
308 	trigger_data->link_speed = SPEED_UNKNOWN;
309 	trigger_data->duplex = DUPLEX_UNKNOWN;
310 	if (trigger_data->net_dev)
311 		get_device_state(trigger_data);
312 
313 	trigger_data->last_activity = 0;
314 
315 	/* Skip if we're called from netdev_trig_activate() and hw_control is true */
316 	if (!trigger_data->hw_control || led_get_trigger_data(trigger_data->led_cdev))
317 		set_baseline_state(trigger_data);
318 
319 	mutex_unlock(&trigger_data->lock);
320 	if (new_dev)
321 		netdev_unlock_ops(new_dev);
322 	rtnl_unlock();
323 
324 	return 0;
325 }
326 
327 static ssize_t device_name_store(struct device *dev,
328 				 struct device_attribute *attr, const char *buf,
329 				 size_t size)
330 {
331 	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
332 	int ret;
333 
334 	ret = set_device_name(trigger_data, buf, size);
335 
336 	if (ret < 0)
337 		return ret;
338 
339 	/* Refresh link_speed visibility */
340 	sysfs_update_group(&dev->kobj, &netdev_trig_link_speed_attrs_group);
341 
342 	return size;
343 }
344 
345 static DEVICE_ATTR_RW(device_name);
346 
347 static ssize_t netdev_led_attr_show(struct device *dev, char *buf,
348 				    enum led_trigger_netdev_modes attr)
349 {
350 	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
351 	int bit;
352 
353 	switch (attr) {
354 	case TRIGGER_NETDEV_LINK:
355 	case TRIGGER_NETDEV_LINK_10:
356 	case TRIGGER_NETDEV_LINK_100:
357 	case TRIGGER_NETDEV_LINK_1000:
358 	case TRIGGER_NETDEV_LINK_2500:
359 	case TRIGGER_NETDEV_LINK_5000:
360 	case TRIGGER_NETDEV_LINK_10000:
361 	case TRIGGER_NETDEV_LINK_25000:
362 	case TRIGGER_NETDEV_LINK_40000:
363 	case TRIGGER_NETDEV_LINK_50000:
364 	case TRIGGER_NETDEV_LINK_100000:
365 	case TRIGGER_NETDEV_HALF_DUPLEX:
366 	case TRIGGER_NETDEV_FULL_DUPLEX:
367 	case TRIGGER_NETDEV_TX:
368 	case TRIGGER_NETDEV_RX:
369 	case TRIGGER_NETDEV_TX_ERR:
370 	case TRIGGER_NETDEV_RX_ERR:
371 		bit = attr;
372 		break;
373 	default:
374 		return -EINVAL;
375 	}
376 
377 	return sprintf(buf, "%u\n", test_bit(bit, &trigger_data->mode));
378 }
379 
380 static ssize_t netdev_led_attr_store(struct device *dev, const char *buf,
381 				     size_t size, enum led_trigger_netdev_modes attr)
382 {
383 	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
384 	struct led_classdev *led_cdev = trigger_data->led_cdev;
385 	unsigned long state, mode = trigger_data->mode;
386 	int ret;
387 	int bit;
388 
389 	ret = kstrtoul(buf, 0, &state);
390 	if (ret)
391 		return ret;
392 
393 	switch (attr) {
394 	case TRIGGER_NETDEV_LINK:
395 	case TRIGGER_NETDEV_LINK_10:
396 	case TRIGGER_NETDEV_LINK_100:
397 	case TRIGGER_NETDEV_LINK_1000:
398 	case TRIGGER_NETDEV_LINK_2500:
399 	case TRIGGER_NETDEV_LINK_5000:
400 	case TRIGGER_NETDEV_LINK_10000:
401 	case TRIGGER_NETDEV_LINK_25000:
402 	case TRIGGER_NETDEV_LINK_40000:
403 	case TRIGGER_NETDEV_LINK_50000:
404 	case TRIGGER_NETDEV_LINK_100000:
405 	case TRIGGER_NETDEV_HALF_DUPLEX:
406 	case TRIGGER_NETDEV_FULL_DUPLEX:
407 	case TRIGGER_NETDEV_TX:
408 	case TRIGGER_NETDEV_RX:
409 	case TRIGGER_NETDEV_TX_ERR:
410 	case TRIGGER_NETDEV_RX_ERR:
411 		bit = attr;
412 		break;
413 	default:
414 		return -EINVAL;
415 	}
416 
417 	if (state)
418 		set_bit(bit, &mode);
419 	else
420 		clear_bit(bit, &mode);
421 
422 	if (test_bit(TRIGGER_NETDEV_LINK, &mode) &&
423 	    (test_bit(TRIGGER_NETDEV_LINK_10, &mode) ||
424 	     test_bit(TRIGGER_NETDEV_LINK_100, &mode) ||
425 	     test_bit(TRIGGER_NETDEV_LINK_1000, &mode) ||
426 	     test_bit(TRIGGER_NETDEV_LINK_2500, &mode) ||
427 	     test_bit(TRIGGER_NETDEV_LINK_5000, &mode) ||
428 	     test_bit(TRIGGER_NETDEV_LINK_10000, &mode) ||
429 	     test_bit(TRIGGER_NETDEV_LINK_25000, &mode) ||
430 	     test_bit(TRIGGER_NETDEV_LINK_40000, &mode) ||
431 	     test_bit(TRIGGER_NETDEV_LINK_50000, &mode) ||
432 	     test_bit(TRIGGER_NETDEV_LINK_100000, &mode)))
433 		return -EINVAL;
434 
435 	cancel_delayed_work_sync(&trigger_data->work);
436 
437 	trigger_data->mode = mode;
438 	trigger_data->hw_control = can_hw_control(trigger_data);
439 
440 	if (!led_cdev->brightness_set && !led_cdev->brightness_set_blocking &&
441 	    !trigger_data->hw_control)
442 		return -EOPNOTSUPP;
443 
444 	set_baseline_state(trigger_data);
445 
446 	return size;
447 }
448 
449 #define DEFINE_NETDEV_TRIGGER(trigger_name, trigger) \
450 	static ssize_t trigger_name##_show(struct device *dev, \
451 		struct device_attribute *attr, char *buf) \
452 	{ \
453 		return netdev_led_attr_show(dev, buf, trigger); \
454 	} \
455 	static ssize_t trigger_name##_store(struct device *dev, \
456 		struct device_attribute *attr, const char *buf, size_t size) \
457 	{ \
458 		return netdev_led_attr_store(dev, buf, size, trigger); \
459 	} \
460 	static DEVICE_ATTR_RW(trigger_name)
461 
462 DEFINE_NETDEV_TRIGGER(link, TRIGGER_NETDEV_LINK);
463 DEFINE_NETDEV_TRIGGER(link_10, TRIGGER_NETDEV_LINK_10);
464 DEFINE_NETDEV_TRIGGER(link_100, TRIGGER_NETDEV_LINK_100);
465 DEFINE_NETDEV_TRIGGER(link_1000, TRIGGER_NETDEV_LINK_1000);
466 DEFINE_NETDEV_TRIGGER(link_2500, TRIGGER_NETDEV_LINK_2500);
467 DEFINE_NETDEV_TRIGGER(link_5000, TRIGGER_NETDEV_LINK_5000);
468 DEFINE_NETDEV_TRIGGER(link_10000, TRIGGER_NETDEV_LINK_10000);
469 DEFINE_NETDEV_TRIGGER(link_25000, TRIGGER_NETDEV_LINK_25000);
470 DEFINE_NETDEV_TRIGGER(link_40000, TRIGGER_NETDEV_LINK_40000);
471 DEFINE_NETDEV_TRIGGER(link_50000, TRIGGER_NETDEV_LINK_50000);
472 DEFINE_NETDEV_TRIGGER(link_100000, TRIGGER_NETDEV_LINK_100000);
473 DEFINE_NETDEV_TRIGGER(half_duplex, TRIGGER_NETDEV_HALF_DUPLEX);
474 DEFINE_NETDEV_TRIGGER(full_duplex, TRIGGER_NETDEV_FULL_DUPLEX);
475 DEFINE_NETDEV_TRIGGER(tx, TRIGGER_NETDEV_TX);
476 DEFINE_NETDEV_TRIGGER(rx, TRIGGER_NETDEV_RX);
477 DEFINE_NETDEV_TRIGGER(tx_err, TRIGGER_NETDEV_TX_ERR);
478 DEFINE_NETDEV_TRIGGER(rx_err, TRIGGER_NETDEV_RX_ERR);
479 
480 static ssize_t interval_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, "%u\n",
486 		       jiffies_to_msecs(atomic_read(&trigger_data->interval)));
487 }
488 
489 static ssize_t interval_store(struct device *dev,
490 			      struct device_attribute *attr, const char *buf,
491 			      size_t size)
492 {
493 	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
494 	unsigned long value;
495 	int ret;
496 
497 	if (trigger_data->hw_control)
498 		return -EINVAL;
499 
500 	ret = kstrtoul(buf, 0, &value);
501 	if (ret)
502 		return ret;
503 
504 	/* impose some basic bounds on the timer interval */
505 	if (value >= 5 && value <= 10000) {
506 		cancel_delayed_work_sync(&trigger_data->work);
507 
508 		atomic_set(&trigger_data->interval, msecs_to_jiffies(value));
509 		set_baseline_state(trigger_data);	/* resets timer */
510 	}
511 
512 	return size;
513 }
514 
515 static DEVICE_ATTR_RW(interval);
516 
517 static ssize_t offloaded_show(struct device *dev,
518 			      struct device_attribute *attr, char *buf)
519 {
520 	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
521 
522 	return sprintf(buf, "%d\n", trigger_data->hw_control);
523 }
524 
525 static DEVICE_ATTR_RO(offloaded);
526 
527 #define CHECK_LINK_MODE_ATTR(link_speed) \
528 	do { \
529 		if (attr == &dev_attr_link_##link_speed.attr && \
530 		    link_ksettings.base.speed == SPEED_##link_speed) \
531 			return attr->mode; \
532 	} while (0)
533 
534 static umode_t netdev_trig_link_speed_visible(struct kobject *kobj,
535 					      struct attribute *attr, int n)
536 {
537 	struct device *dev = kobj_to_dev(kobj);
538 	struct led_netdev_data *trigger_data;
539 	unsigned long *supported_link_modes;
540 	u32 mode;
541 
542 	trigger_data = led_trigger_get_drvdata(dev);
543 	supported_link_modes = trigger_data->supported_link_modes;
544 
545 	/*
546 	 * Search in the supported link mode mask a matching supported mode.
547 	 * Stop at the first matching entry as we care only to check if a particular
548 	 * speed is supported and not the kind.
549 	 */
550 	for_each_set_bit(mode, supported_link_modes, __ETHTOOL_LINK_MODE_MASK_NBITS) {
551 		struct ethtool_link_ksettings link_ksettings;
552 
553 		ethtool_params_from_link_mode(&link_ksettings, mode);
554 
555 		CHECK_LINK_MODE_ATTR(10);
556 		CHECK_LINK_MODE_ATTR(100);
557 		CHECK_LINK_MODE_ATTR(1000);
558 		CHECK_LINK_MODE_ATTR(2500);
559 		CHECK_LINK_MODE_ATTR(5000);
560 		CHECK_LINK_MODE_ATTR(10000);
561 		CHECK_LINK_MODE_ATTR(25000);
562 		CHECK_LINK_MODE_ATTR(40000);
563 		CHECK_LINK_MODE_ATTR(50000);
564 		CHECK_LINK_MODE_ATTR(100000);
565 	}
566 
567 	return 0;
568 }
569 
570 static struct attribute *netdev_trig_link_speed_attrs[] = {
571 	&dev_attr_link_10.attr,
572 	&dev_attr_link_100.attr,
573 	&dev_attr_link_1000.attr,
574 	&dev_attr_link_2500.attr,
575 	&dev_attr_link_5000.attr,
576 	&dev_attr_link_10000.attr,
577 	&dev_attr_link_25000.attr,
578 	&dev_attr_link_40000.attr,
579 	&dev_attr_link_50000.attr,
580 	&dev_attr_link_100000.attr,
581 	NULL
582 };
583 
584 static const struct attribute_group netdev_trig_link_speed_attrs_group = {
585 	.attrs = netdev_trig_link_speed_attrs,
586 	.is_visible = netdev_trig_link_speed_visible,
587 };
588 
589 static struct attribute *netdev_trig_attrs[] = {
590 	&dev_attr_device_name.attr,
591 	&dev_attr_link.attr,
592 	&dev_attr_full_duplex.attr,
593 	&dev_attr_half_duplex.attr,
594 	&dev_attr_rx.attr,
595 	&dev_attr_tx.attr,
596 	&dev_attr_rx_err.attr,
597 	&dev_attr_tx_err.attr,
598 	&dev_attr_interval.attr,
599 	&dev_attr_offloaded.attr,
600 	NULL
601 };
602 
603 static const struct attribute_group netdev_trig_attrs_group = {
604 	.attrs = netdev_trig_attrs,
605 };
606 
607 static const struct attribute_group *netdev_trig_groups[] = {
608 	&netdev_trig_attrs_group,
609 	&netdev_trig_link_speed_attrs_group,
610 	NULL,
611 };
612 
613 static int netdev_trig_notify(struct notifier_block *nb,
614 			      unsigned long evt, void *dv)
615 {
616 	struct net_device *dev =
617 		netdev_notifier_info_to_dev((struct netdev_notifier_info *)dv);
618 	struct led_netdev_data *trigger_data =
619 		container_of(nb, struct led_netdev_data, notifier);
620 	struct led_classdev *led_cdev = trigger_data->led_cdev;
621 
622 	if (evt != NETDEV_UP && evt != NETDEV_DOWN && evt != NETDEV_CHANGE
623 	    && evt != NETDEV_REGISTER && evt != NETDEV_UNREGISTER
624 	    && evt != NETDEV_CHANGENAME)
625 		return NOTIFY_DONE;
626 
627 	if (!(dev == trigger_data->net_dev ||
628 	      (evt == NETDEV_CHANGENAME && !strcmp(dev->name, trigger_data->device_name)) ||
629 	      (evt == NETDEV_REGISTER && !strcmp(dev->name, trigger_data->device_name))))
630 		return NOTIFY_DONE;
631 
632 	cancel_delayed_work_sync(&trigger_data->work);
633 
634 	mutex_lock(&trigger_data->lock);
635 
636 	trigger_data->carrier_link_up = false;
637 	trigger_data->link_speed = SPEED_UNKNOWN;
638 	trigger_data->duplex = DUPLEX_UNKNOWN;
639 	switch (evt) {
640 	case NETDEV_CHANGENAME:
641 	case NETDEV_REGISTER:
642 		dev_put(trigger_data->net_dev);
643 		dev_hold(dev);
644 		trigger_data->net_dev = dev;
645 		if (evt == NETDEV_CHANGENAME)
646 			get_device_state(trigger_data);
647 		break;
648 	case NETDEV_UNREGISTER:
649 		dev_put(trigger_data->net_dev);
650 		trigger_data->net_dev = NULL;
651 		break;
652 	case NETDEV_UP:
653 		trigger_data->hw_control = can_hw_control(trigger_data);
654 		fallthrough;
655 	case NETDEV_CHANGE:
656 		get_device_state(trigger_data);
657 		/* Refresh link_speed visibility */
658 		if (evt == NETDEV_CHANGE)
659 			sysfs_update_group(&led_cdev->dev->kobj,
660 					   &netdev_trig_link_speed_attrs_group);
661 		break;
662 	}
663 
664 	set_baseline_state(trigger_data);
665 
666 	mutex_unlock(&trigger_data->lock);
667 
668 	return NOTIFY_DONE;
669 }
670 
671 /* here's the real work! */
672 static void netdev_trig_work(struct work_struct *work)
673 {
674 	struct led_netdev_data *trigger_data =
675 		container_of(work, struct led_netdev_data, work.work);
676 	struct rtnl_link_stats64 *dev_stats;
677 	unsigned int new_activity;
678 	struct rtnl_link_stats64 temp;
679 	unsigned long interval;
680 	int invert;
681 
682 	/* If we dont have a device, insure we are off */
683 	if (!trigger_data->net_dev) {
684 		led_set_brightness(trigger_data->led_cdev, LED_OFF);
685 		return;
686 	}
687 
688 	/* If we are not looking for RX/TX then return  */
689 	if (!test_bit(TRIGGER_NETDEV_TX, &trigger_data->mode) &&
690 	    !test_bit(TRIGGER_NETDEV_RX, &trigger_data->mode) &&
691 	    !test_bit(TRIGGER_NETDEV_TX_ERR, &trigger_data->mode) &&
692 	    !test_bit(TRIGGER_NETDEV_RX_ERR, &trigger_data->mode))
693 		return;
694 
695 	dev_stats = dev_get_stats(trigger_data->net_dev, &temp);
696 	new_activity =
697 	    (test_bit(TRIGGER_NETDEV_TX, &trigger_data->mode) ?
698 		dev_stats->tx_packets : 0) +
699 	    (test_bit(TRIGGER_NETDEV_RX, &trigger_data->mode) ?
700 		dev_stats->rx_packets : 0) +
701 	    (test_bit(TRIGGER_NETDEV_TX_ERR, &trigger_data->mode) ?
702 		dev_stats->tx_errors : 0) +
703 	    (test_bit(TRIGGER_NETDEV_RX_ERR, &trigger_data->mode) ?
704 		dev_stats->rx_errors : 0);
705 
706 	if (trigger_data->last_activity != new_activity) {
707 		led_stop_software_blink(trigger_data->led_cdev);
708 
709 		invert = test_bit(TRIGGER_NETDEV_LINK, &trigger_data->mode) ||
710 			 test_bit(TRIGGER_NETDEV_LINK_10, &trigger_data->mode) ||
711 			 test_bit(TRIGGER_NETDEV_LINK_100, &trigger_data->mode) ||
712 			 test_bit(TRIGGER_NETDEV_LINK_1000, &trigger_data->mode) ||
713 			 test_bit(TRIGGER_NETDEV_LINK_2500, &trigger_data->mode) ||
714 			 test_bit(TRIGGER_NETDEV_LINK_5000, &trigger_data->mode) ||
715 			 test_bit(TRIGGER_NETDEV_LINK_10000, &trigger_data->mode) ||
716 			 test_bit(TRIGGER_NETDEV_LINK_25000, &trigger_data->mode) ||
717 			 test_bit(TRIGGER_NETDEV_LINK_40000, &trigger_data->mode) ||
718 			 test_bit(TRIGGER_NETDEV_LINK_50000, &trigger_data->mode) ||
719 			 test_bit(TRIGGER_NETDEV_LINK_100000, &trigger_data->mode) ||
720 			 test_bit(TRIGGER_NETDEV_HALF_DUPLEX, &trigger_data->mode) ||
721 			 test_bit(TRIGGER_NETDEV_FULL_DUPLEX, &trigger_data->mode);
722 		interval = jiffies_to_msecs(
723 				atomic_read(&trigger_data->interval));
724 		/* base state is ON (link present) */
725 		led_blink_set_oneshot(trigger_data->led_cdev,
726 				      &interval,
727 				      &interval,
728 				      invert);
729 		trigger_data->last_activity = new_activity;
730 	}
731 
732 	schedule_delayed_work(&trigger_data->work,
733 			(atomic_read(&trigger_data->interval)*2));
734 }
735 
736 static int netdev_trig_activate(struct led_classdev *led_cdev)
737 {
738 	struct led_netdev_data *trigger_data;
739 	unsigned long mode = 0;
740 	struct device *dev;
741 	int rc;
742 
743 	trigger_data = kzalloc_obj(struct led_netdev_data);
744 	if (!trigger_data)
745 		return -ENOMEM;
746 
747 	mutex_init(&trigger_data->lock);
748 
749 	trigger_data->notifier.notifier_call = netdev_trig_notify;
750 	trigger_data->notifier.priority = 10;
751 
752 	INIT_DELAYED_WORK(&trigger_data->work, netdev_trig_work);
753 
754 	trigger_data->led_cdev = led_cdev;
755 	trigger_data->net_dev = NULL;
756 	trigger_data->device_name[0] = 0;
757 
758 	trigger_data->mode = 0;
759 	atomic_set(&trigger_data->interval, msecs_to_jiffies(NETDEV_LED_DEFAULT_INTERVAL));
760 	trigger_data->last_activity = 0;
761 
762 	/* Check if hw control is active by default on the LED.
763 	 * Init already enabled mode in hw control.
764 	 */
765 	if (supports_hw_control(led_cdev)) {
766 		dev = led_cdev->hw_control_get_device(led_cdev);
767 		if (dev) {
768 			const char *name = dev_name(dev);
769 
770 			trigger_data->hw_control = true;
771 			set_device_name(trigger_data, name, strlen(name));
772 
773 			rc = led_cdev->hw_control_get(led_cdev, &mode);
774 			if (!rc)
775 				trigger_data->mode = mode;
776 		}
777 	}
778 
779 	led_set_trigger_data(led_cdev, trigger_data);
780 
781 	rc = register_netdevice_notifier(&trigger_data->notifier);
782 	if (rc)
783 		kfree(trigger_data);
784 
785 	return rc;
786 }
787 
788 static void netdev_trig_deactivate(struct led_classdev *led_cdev)
789 {
790 	struct led_netdev_data *trigger_data = led_get_trigger_data(led_cdev);
791 
792 	unregister_netdevice_notifier(&trigger_data->notifier);
793 
794 	cancel_delayed_work_sync(&trigger_data->work);
795 
796 	dev_put(trigger_data->net_dev);
797 
798 	kfree(trigger_data);
799 }
800 
801 static struct led_trigger netdev_led_trigger = {
802 	.name = "netdev",
803 	.activate = netdev_trig_activate,
804 	.deactivate = netdev_trig_deactivate,
805 	.groups = netdev_trig_groups,
806 };
807 
808 module_led_trigger(netdev_led_trigger);
809 
810 MODULE_AUTHOR("Ben Whitten <ben.whitten@gmail.com>");
811 MODULE_AUTHOR("Oliver Jowett <oliver@opencloud.com>");
812 MODULE_DESCRIPTION("Netdev LED trigger");
813 MODULE_LICENSE("GPL v2");
814 MODULE_ALIAS("ledtrig:netdev");
815