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 
57 struct 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 	unsigned long blink_delay;
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 
set_baseline_state(struct led_netdev_data * trigger_data)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 		if (led_cdev->blink_set) {
91 			led_cdev->blink_set(led_cdev, &trigger_data->blink_delay,
92 					    &trigger_data->blink_delay);
93 		}
94 
95 		return;
96 	}
97 
98 	current_brightness = led_cdev->brightness;
99 	if (current_brightness)
100 		led_cdev->blink_brightness = current_brightness;
101 	if (!led_cdev->blink_brightness)
102 		led_cdev->blink_brightness = led_cdev->max_brightness;
103 
104 	if (!trigger_data->carrier_link_up) {
105 		led_set_brightness(led_cdev, LED_OFF);
106 	} else {
107 		bool blink_on = false;
108 
109 		if (test_bit(TRIGGER_NETDEV_LINK, &trigger_data->mode))
110 			blink_on = true;
111 
112 		if (test_bit(TRIGGER_NETDEV_LINK_10, &trigger_data->mode) &&
113 		    trigger_data->link_speed == SPEED_10)
114 			blink_on = true;
115 
116 		if (test_bit(TRIGGER_NETDEV_LINK_100, &trigger_data->mode) &&
117 		    trigger_data->link_speed == SPEED_100)
118 			blink_on = true;
119 
120 		if (test_bit(TRIGGER_NETDEV_LINK_1000, &trigger_data->mode) &&
121 		    trigger_data->link_speed == SPEED_1000)
122 			blink_on = true;
123 
124 		if (test_bit(TRIGGER_NETDEV_LINK_2500, &trigger_data->mode) &&
125 		    trigger_data->link_speed == SPEED_2500)
126 			blink_on = true;
127 
128 		if (test_bit(TRIGGER_NETDEV_LINK_5000, &trigger_data->mode) &&
129 		    trigger_data->link_speed == SPEED_5000)
130 			blink_on = true;
131 
132 		if (test_bit(TRIGGER_NETDEV_LINK_10000, &trigger_data->mode) &&
133 		    trigger_data->link_speed == SPEED_10000)
134 			blink_on = true;
135 
136 		if (test_bit(TRIGGER_NETDEV_HALF_DUPLEX, &trigger_data->mode) &&
137 		    trigger_data->duplex == DUPLEX_HALF)
138 			blink_on = true;
139 
140 		if (test_bit(TRIGGER_NETDEV_FULL_DUPLEX, &trigger_data->mode) &&
141 		    trigger_data->duplex == DUPLEX_FULL)
142 			blink_on = true;
143 
144 		if (blink_on)
145 			led_set_brightness(led_cdev,
146 					   led_cdev->blink_brightness);
147 		else
148 			led_set_brightness(led_cdev, LED_OFF);
149 
150 		/* If we are looking for RX/TX start periodically
151 		 * checking stats
152 		 */
153 		if (test_bit(TRIGGER_NETDEV_TX, &trigger_data->mode) ||
154 		    test_bit(TRIGGER_NETDEV_RX, &trigger_data->mode) ||
155 		    test_bit(TRIGGER_NETDEV_TX_ERR, &trigger_data->mode) ||
156 		    test_bit(TRIGGER_NETDEV_RX_ERR, &trigger_data->mode))
157 			schedule_delayed_work(&trigger_data->work, 0);
158 	}
159 }
160 
supports_hw_control(struct led_classdev * led_cdev)161 static bool supports_hw_control(struct led_classdev *led_cdev)
162 {
163 	if (!led_cdev->hw_control_get || !led_cdev->hw_control_set ||
164 	    !led_cdev->hw_control_is_supported)
165 		return false;
166 
167 	return !strcmp(led_cdev->hw_control_trigger, led_cdev->trigger->name);
168 }
169 
170 /*
171  * Validate the configured netdev is the same as the one associated with
172  * the LED driver in hw control.
173  */
validate_net_dev(struct led_classdev * led_cdev,struct net_device * net_dev)174 static bool validate_net_dev(struct led_classdev *led_cdev,
175 			     struct net_device *net_dev)
176 {
177 	struct device *dev = led_cdev->hw_control_get_device(led_cdev);
178 	struct net_device *ndev;
179 
180 	if (!dev)
181 		return false;
182 
183 	ndev = to_net_dev(dev);
184 
185 	return ndev == net_dev;
186 }
187 
can_hw_control(struct led_netdev_data * trigger_data)188 static bool can_hw_control(struct led_netdev_data *trigger_data)
189 {
190 	unsigned long default_interval = msecs_to_jiffies(NETDEV_LED_DEFAULT_INTERVAL);
191 	unsigned int interval = atomic_read(&trigger_data->interval);
192 	struct led_classdev *led_cdev = trigger_data->led_cdev;
193 	int ret;
194 
195 	if (!supports_hw_control(led_cdev))
196 		return false;
197 
198 	/*
199 	 * Interval must be set to the default
200 	 * value. Any different value is rejected if in hw
201 	 * control.
202 	 */
203 	if (interval != default_interval)
204 		return false;
205 
206 	/*
207 	 * net_dev must be set with hw control, otherwise no
208 	 * blinking can be happening and there is nothing to
209 	 * offloaded. Additionally, for hw control to be
210 	 * valid, the configured netdev must be the same as
211 	 * netdev associated to the LED.
212 	 */
213 	if (!validate_net_dev(led_cdev, trigger_data->net_dev))
214 		return false;
215 
216 	/* Check if the requested mode is supported */
217 	ret = led_cdev->hw_control_is_supported(led_cdev, trigger_data->mode);
218 	/* Fall back to software blinking if not supported */
219 	if (ret == -EOPNOTSUPP)
220 		return false;
221 	if (ret) {
222 		dev_warn(led_cdev->dev,
223 			 "Current mode check failed with error %d\n", ret);
224 		return false;
225 	}
226 
227 	return true;
228 }
229 
get_device_state(struct led_netdev_data * trigger_data)230 static void get_device_state(struct led_netdev_data *trigger_data)
231 {
232 	struct ethtool_link_ksettings cmd;
233 
234 	trigger_data->carrier_link_up = netif_carrier_ok(trigger_data->net_dev);
235 
236 	if (__ethtool_get_link_ksettings(trigger_data->net_dev, &cmd))
237 		return;
238 
239 	if (trigger_data->carrier_link_up) {
240 		trigger_data->link_speed = cmd.base.speed;
241 		trigger_data->duplex = cmd.base.duplex;
242 	}
243 
244 	/*
245 	 * Have a local copy of the link speed supported to avoid rtnl lock every time
246 	 * modes are refreshed on any change event
247 	 */
248 	linkmode_copy(trigger_data->supported_link_modes, cmd.link_modes.supported);
249 }
250 
device_name_show(struct device * dev,struct device_attribute * attr,char * buf)251 static ssize_t device_name_show(struct device *dev,
252 				struct device_attribute *attr, char *buf)
253 {
254 	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
255 	ssize_t len;
256 
257 	mutex_lock(&trigger_data->lock);
258 	len = sprintf(buf, "%s\n", trigger_data->device_name);
259 	mutex_unlock(&trigger_data->lock);
260 
261 	return len;
262 }
263 
set_device_name(struct led_netdev_data * trigger_data,const char * name,size_t size)264 static int set_device_name(struct led_netdev_data *trigger_data,
265 			   const char *name, size_t size)
266 {
267 	if (size >= IFNAMSIZ)
268 		return -EINVAL;
269 
270 	cancel_delayed_work_sync(&trigger_data->work);
271 
272 	/*
273 	 * Take RTNL lock before trigger_data lock to prevent potential
274 	 * deadlock with netdev notifier registration.
275 	 */
276 	rtnl_lock();
277 	mutex_lock(&trigger_data->lock);
278 
279 	if (trigger_data->net_dev) {
280 		dev_put(trigger_data->net_dev);
281 		trigger_data->net_dev = NULL;
282 	}
283 
284 	memcpy(trigger_data->device_name, name, size);
285 	trigger_data->device_name[size] = 0;
286 	if (size > 0 && trigger_data->device_name[size - 1] == '\n')
287 		trigger_data->device_name[size - 1] = 0;
288 
289 	if (trigger_data->device_name[0] != 0)
290 		trigger_data->net_dev =
291 		    dev_get_by_name(&init_net, trigger_data->device_name);
292 
293 	trigger_data->carrier_link_up = false;
294 	trigger_data->link_speed = SPEED_UNKNOWN;
295 	trigger_data->duplex = DUPLEX_UNKNOWN;
296 	if (trigger_data->net_dev)
297 		get_device_state(trigger_data);
298 
299 	trigger_data->last_activity = 0;
300 
301 	/* Skip if we're called from netdev_trig_activate() and hw_control is true */
302 	if (!trigger_data->hw_control || led_get_trigger_data(trigger_data->led_cdev))
303 		set_baseline_state(trigger_data);
304 
305 	mutex_unlock(&trigger_data->lock);
306 	rtnl_unlock();
307 
308 	return 0;
309 }
310 
device_name_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)311 static ssize_t device_name_store(struct device *dev,
312 				 struct device_attribute *attr, const char *buf,
313 				 size_t size)
314 {
315 	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
316 	int ret;
317 
318 	ret = set_device_name(trigger_data, buf, size);
319 
320 	if (ret < 0)
321 		return ret;
322 
323 	/* Refresh link_speed visibility */
324 	sysfs_update_group(&dev->kobj, &netdev_trig_link_speed_attrs_group);
325 
326 	return size;
327 }
328 
329 static DEVICE_ATTR_RW(device_name);
330 
netdev_led_attr_show(struct device * dev,char * buf,enum led_trigger_netdev_modes attr)331 static ssize_t netdev_led_attr_show(struct device *dev, char *buf,
332 				    enum led_trigger_netdev_modes attr)
333 {
334 	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
335 	int bit;
336 
337 	switch (attr) {
338 	case TRIGGER_NETDEV_LINK:
339 	case TRIGGER_NETDEV_LINK_10:
340 	case TRIGGER_NETDEV_LINK_100:
341 	case TRIGGER_NETDEV_LINK_1000:
342 	case TRIGGER_NETDEV_LINK_2500:
343 	case TRIGGER_NETDEV_LINK_5000:
344 	case TRIGGER_NETDEV_LINK_10000:
345 	case TRIGGER_NETDEV_HALF_DUPLEX:
346 	case TRIGGER_NETDEV_FULL_DUPLEX:
347 	case TRIGGER_NETDEV_TX:
348 	case TRIGGER_NETDEV_RX:
349 	case TRIGGER_NETDEV_TX_ERR:
350 	case TRIGGER_NETDEV_RX_ERR:
351 		bit = attr;
352 		break;
353 	default:
354 		return -EINVAL;
355 	}
356 
357 	return sprintf(buf, "%u\n", test_bit(bit, &trigger_data->mode));
358 }
359 
netdev_led_attr_store(struct device * dev,const char * buf,size_t size,enum led_trigger_netdev_modes attr)360 static ssize_t netdev_led_attr_store(struct device *dev, const char *buf,
361 				     size_t size, enum led_trigger_netdev_modes attr)
362 {
363 	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
364 	struct led_classdev *led_cdev = trigger_data->led_cdev;
365 	unsigned long state, mode = trigger_data->mode;
366 	int ret;
367 	int bit;
368 
369 	ret = kstrtoul(buf, 0, &state);
370 	if (ret)
371 		return ret;
372 
373 	switch (attr) {
374 	case TRIGGER_NETDEV_LINK:
375 	case TRIGGER_NETDEV_LINK_10:
376 	case TRIGGER_NETDEV_LINK_100:
377 	case TRIGGER_NETDEV_LINK_1000:
378 	case TRIGGER_NETDEV_LINK_2500:
379 	case TRIGGER_NETDEV_LINK_5000:
380 	case TRIGGER_NETDEV_LINK_10000:
381 	case TRIGGER_NETDEV_HALF_DUPLEX:
382 	case TRIGGER_NETDEV_FULL_DUPLEX:
383 	case TRIGGER_NETDEV_TX:
384 	case TRIGGER_NETDEV_RX:
385 	case TRIGGER_NETDEV_TX_ERR:
386 	case TRIGGER_NETDEV_RX_ERR:
387 		bit = attr;
388 		break;
389 	default:
390 		return -EINVAL;
391 	}
392 
393 	if (state)
394 		set_bit(bit, &mode);
395 	else
396 		clear_bit(bit, &mode);
397 
398 	if (test_bit(TRIGGER_NETDEV_LINK, &mode) &&
399 	    (test_bit(TRIGGER_NETDEV_LINK_10, &mode) ||
400 	     test_bit(TRIGGER_NETDEV_LINK_100, &mode) ||
401 	     test_bit(TRIGGER_NETDEV_LINK_1000, &mode) ||
402 	     test_bit(TRIGGER_NETDEV_LINK_2500, &mode) ||
403 	     test_bit(TRIGGER_NETDEV_LINK_5000, &mode) ||
404 	     test_bit(TRIGGER_NETDEV_LINK_10000, &mode)))
405 		return -EINVAL;
406 
407 	cancel_delayed_work_sync(&trigger_data->work);
408 
409 	trigger_data->mode = mode;
410 	trigger_data->hw_control = can_hw_control(trigger_data);
411 
412 	if (!led_cdev->brightness_set && !led_cdev->brightness_set_blocking &&
413 	    !trigger_data->hw_control)
414 		return -EOPNOTSUPP;
415 
416 	set_baseline_state(trigger_data);
417 
418 	return size;
419 }
420 
421 #define DEFINE_NETDEV_TRIGGER(trigger_name, trigger) \
422 	static ssize_t trigger_name##_show(struct device *dev, \
423 		struct device_attribute *attr, char *buf) \
424 	{ \
425 		return netdev_led_attr_show(dev, buf, trigger); \
426 	} \
427 	static ssize_t trigger_name##_store(struct device *dev, \
428 		struct device_attribute *attr, const char *buf, size_t size) \
429 	{ \
430 		return netdev_led_attr_store(dev, buf, size, trigger); \
431 	} \
432 	static DEVICE_ATTR_RW(trigger_name)
433 
434 DEFINE_NETDEV_TRIGGER(link, TRIGGER_NETDEV_LINK);
435 DEFINE_NETDEV_TRIGGER(link_10, TRIGGER_NETDEV_LINK_10);
436 DEFINE_NETDEV_TRIGGER(link_100, TRIGGER_NETDEV_LINK_100);
437 DEFINE_NETDEV_TRIGGER(link_1000, TRIGGER_NETDEV_LINK_1000);
438 DEFINE_NETDEV_TRIGGER(link_2500, TRIGGER_NETDEV_LINK_2500);
439 DEFINE_NETDEV_TRIGGER(link_5000, TRIGGER_NETDEV_LINK_5000);
440 DEFINE_NETDEV_TRIGGER(link_10000, TRIGGER_NETDEV_LINK_10000);
441 DEFINE_NETDEV_TRIGGER(half_duplex, TRIGGER_NETDEV_HALF_DUPLEX);
442 DEFINE_NETDEV_TRIGGER(full_duplex, TRIGGER_NETDEV_FULL_DUPLEX);
443 DEFINE_NETDEV_TRIGGER(tx, TRIGGER_NETDEV_TX);
444 DEFINE_NETDEV_TRIGGER(rx, TRIGGER_NETDEV_RX);
445 DEFINE_NETDEV_TRIGGER(tx_err, TRIGGER_NETDEV_TX_ERR);
446 DEFINE_NETDEV_TRIGGER(rx_err, TRIGGER_NETDEV_RX_ERR);
447 
interval_show(struct device * dev,struct device_attribute * attr,char * buf)448 static ssize_t interval_show(struct device *dev,
449 			     struct device_attribute *attr, char *buf)
450 {
451 	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
452 
453 	return sprintf(buf, "%u\n",
454 		       jiffies_to_msecs(atomic_read(&trigger_data->interval)));
455 }
456 
interval_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)457 static ssize_t interval_store(struct device *dev,
458 			      struct device_attribute *attr, const char *buf,
459 			      size_t size)
460 {
461 	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
462 	struct led_classdev *led_cdev = trigger_data->led_cdev;
463 	unsigned long value;
464 	int ret;
465 
466 	if (trigger_data->hw_control && !led_cdev->blink_set)
467 		return -EINVAL;
468 
469 	ret = kstrtoul(buf, 0, &value);
470 	if (ret)
471 		return ret;
472 
473 	/* impose some basic bounds on the timer interval */
474 	if (value >= 5 && value <= 10000) {
475 		if (trigger_data->hw_control) {
476 			trigger_data->blink_delay = value;
477 		} else {
478 			cancel_delayed_work_sync(&trigger_data->work);
479 
480 			atomic_set(&trigger_data->interval, msecs_to_jiffies(value));
481 		}
482 		set_baseline_state(trigger_data);	/* resets timer */
483 	}
484 
485 	return size;
486 }
487 
488 static DEVICE_ATTR_RW(interval);
489 
offloaded_show(struct device * dev,struct device_attribute * attr,char * buf)490 static ssize_t offloaded_show(struct device *dev,
491 			      struct device_attribute *attr, char *buf)
492 {
493 	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
494 
495 	return sprintf(buf, "%d\n", trigger_data->hw_control);
496 }
497 
498 static DEVICE_ATTR_RO(offloaded);
499 
500 #define CHECK_LINK_MODE_ATTR(link_speed) \
501 	do { \
502 		if (attr == &dev_attr_link_##link_speed.attr && \
503 		    link_ksettings.base.speed == SPEED_##link_speed) \
504 			return attr->mode; \
505 	} while (0)
506 
netdev_trig_link_speed_visible(struct kobject * kobj,struct attribute * attr,int n)507 static umode_t netdev_trig_link_speed_visible(struct kobject *kobj,
508 					      struct attribute *attr, int n)
509 {
510 	struct device *dev = kobj_to_dev(kobj);
511 	struct led_netdev_data *trigger_data;
512 	unsigned long *supported_link_modes;
513 	u32 mode;
514 
515 	trigger_data = led_trigger_get_drvdata(dev);
516 	supported_link_modes = trigger_data->supported_link_modes;
517 
518 	/*
519 	 * Search in the supported link mode mask a matching supported mode.
520 	 * Stop at the first matching entry as we care only to check if a particular
521 	 * speed is supported and not the kind.
522 	 */
523 	for_each_set_bit(mode, supported_link_modes, __ETHTOOL_LINK_MODE_MASK_NBITS) {
524 		struct ethtool_link_ksettings link_ksettings;
525 
526 		ethtool_params_from_link_mode(&link_ksettings, mode);
527 
528 		CHECK_LINK_MODE_ATTR(10);
529 		CHECK_LINK_MODE_ATTR(100);
530 		CHECK_LINK_MODE_ATTR(1000);
531 		CHECK_LINK_MODE_ATTR(2500);
532 		CHECK_LINK_MODE_ATTR(5000);
533 		CHECK_LINK_MODE_ATTR(10000);
534 	}
535 
536 	return 0;
537 }
538 
539 static struct attribute *netdev_trig_link_speed_attrs[] = {
540 	&dev_attr_link_10.attr,
541 	&dev_attr_link_100.attr,
542 	&dev_attr_link_1000.attr,
543 	&dev_attr_link_2500.attr,
544 	&dev_attr_link_5000.attr,
545 	&dev_attr_link_10000.attr,
546 	NULL
547 };
548 
549 static const struct attribute_group netdev_trig_link_speed_attrs_group = {
550 	.attrs = netdev_trig_link_speed_attrs,
551 	.is_visible = netdev_trig_link_speed_visible,
552 };
553 
554 static struct attribute *netdev_trig_attrs[] = {
555 	&dev_attr_device_name.attr,
556 	&dev_attr_link.attr,
557 	&dev_attr_full_duplex.attr,
558 	&dev_attr_half_duplex.attr,
559 	&dev_attr_rx.attr,
560 	&dev_attr_tx.attr,
561 	&dev_attr_rx_err.attr,
562 	&dev_attr_tx_err.attr,
563 	&dev_attr_interval.attr,
564 	&dev_attr_offloaded.attr,
565 	NULL
566 };
567 
568 static const struct attribute_group netdev_trig_attrs_group = {
569 	.attrs = netdev_trig_attrs,
570 };
571 
572 static const struct attribute_group *netdev_trig_groups[] = {
573 	&netdev_trig_attrs_group,
574 	&netdev_trig_link_speed_attrs_group,
575 	NULL,
576 };
577 
netdev_trig_notify(struct notifier_block * nb,unsigned long evt,void * dv)578 static int netdev_trig_notify(struct notifier_block *nb,
579 			      unsigned long evt, void *dv)
580 {
581 	struct net_device *dev =
582 		netdev_notifier_info_to_dev((struct netdev_notifier_info *)dv);
583 	struct led_netdev_data *trigger_data =
584 		container_of(nb, struct led_netdev_data, notifier);
585 	struct led_classdev *led_cdev = trigger_data->led_cdev;
586 
587 	if (evt != NETDEV_UP && evt != NETDEV_DOWN && evt != NETDEV_CHANGE
588 	    && evt != NETDEV_REGISTER && evt != NETDEV_UNREGISTER
589 	    && evt != NETDEV_CHANGENAME)
590 		return NOTIFY_DONE;
591 
592 	if (!(dev == trigger_data->net_dev ||
593 	      (evt == NETDEV_CHANGENAME && !strcmp(dev->name, trigger_data->device_name)) ||
594 	      (evt == NETDEV_REGISTER && !strcmp(dev->name, trigger_data->device_name))))
595 		return NOTIFY_DONE;
596 
597 	cancel_delayed_work_sync(&trigger_data->work);
598 
599 	mutex_lock(&trigger_data->lock);
600 
601 	trigger_data->carrier_link_up = false;
602 	trigger_data->link_speed = SPEED_UNKNOWN;
603 	trigger_data->duplex = DUPLEX_UNKNOWN;
604 	switch (evt) {
605 	case NETDEV_CHANGENAME:
606 	case NETDEV_REGISTER:
607 		dev_put(trigger_data->net_dev);
608 		dev_hold(dev);
609 		trigger_data->net_dev = dev;
610 		if (evt == NETDEV_CHANGENAME)
611 			get_device_state(trigger_data);
612 		break;
613 	case NETDEV_UNREGISTER:
614 		dev_put(trigger_data->net_dev);
615 		trigger_data->net_dev = NULL;
616 		break;
617 	case NETDEV_UP:
618 		trigger_data->hw_control = can_hw_control(trigger_data);
619 		fallthrough;
620 	case NETDEV_CHANGE:
621 		get_device_state(trigger_data);
622 		/* Refresh link_speed visibility */
623 		if (evt == NETDEV_CHANGE)
624 			sysfs_update_group(&led_cdev->dev->kobj,
625 					   &netdev_trig_link_speed_attrs_group);
626 		break;
627 	}
628 
629 	set_baseline_state(trigger_data);
630 
631 	mutex_unlock(&trigger_data->lock);
632 
633 	return NOTIFY_DONE;
634 }
635 
636 /* here's the real work! */
netdev_trig_work(struct work_struct * work)637 static void netdev_trig_work(struct work_struct *work)
638 {
639 	struct led_netdev_data *trigger_data =
640 		container_of(work, struct led_netdev_data, work.work);
641 	struct rtnl_link_stats64 *dev_stats;
642 	unsigned int new_activity;
643 	struct rtnl_link_stats64 temp;
644 	unsigned long interval;
645 	int invert;
646 
647 	/* If we dont have a device, insure we are off */
648 	if (!trigger_data->net_dev) {
649 		led_set_brightness(trigger_data->led_cdev, LED_OFF);
650 		return;
651 	}
652 
653 	/* If we are not looking for RX/TX then return  */
654 	if (!test_bit(TRIGGER_NETDEV_TX, &trigger_data->mode) &&
655 	    !test_bit(TRIGGER_NETDEV_RX, &trigger_data->mode) &&
656 	    !test_bit(TRIGGER_NETDEV_TX_ERR, &trigger_data->mode) &&
657 	    !test_bit(TRIGGER_NETDEV_RX_ERR, &trigger_data->mode))
658 		return;
659 
660 	dev_stats = dev_get_stats(trigger_data->net_dev, &temp);
661 	new_activity =
662 	    (test_bit(TRIGGER_NETDEV_TX, &trigger_data->mode) ?
663 		dev_stats->tx_packets : 0) +
664 	    (test_bit(TRIGGER_NETDEV_RX, &trigger_data->mode) ?
665 		dev_stats->rx_packets : 0) +
666 	    (test_bit(TRIGGER_NETDEV_TX_ERR, &trigger_data->mode) ?
667 		dev_stats->tx_errors : 0) +
668 	    (test_bit(TRIGGER_NETDEV_RX_ERR, &trigger_data->mode) ?
669 		dev_stats->rx_errors : 0);
670 
671 	if (trigger_data->last_activity != new_activity) {
672 		led_stop_software_blink(trigger_data->led_cdev);
673 
674 		invert = test_bit(TRIGGER_NETDEV_LINK, &trigger_data->mode) ||
675 			 test_bit(TRIGGER_NETDEV_LINK_10, &trigger_data->mode) ||
676 			 test_bit(TRIGGER_NETDEV_LINK_100, &trigger_data->mode) ||
677 			 test_bit(TRIGGER_NETDEV_LINK_1000, &trigger_data->mode) ||
678 			 test_bit(TRIGGER_NETDEV_LINK_2500, &trigger_data->mode) ||
679 			 test_bit(TRIGGER_NETDEV_LINK_5000, &trigger_data->mode) ||
680 			 test_bit(TRIGGER_NETDEV_LINK_10000, &trigger_data->mode) ||
681 			 test_bit(TRIGGER_NETDEV_HALF_DUPLEX, &trigger_data->mode) ||
682 			 test_bit(TRIGGER_NETDEV_FULL_DUPLEX, &trigger_data->mode);
683 		interval = jiffies_to_msecs(
684 				atomic_read(&trigger_data->interval));
685 		/* base state is ON (link present) */
686 		led_blink_set_oneshot(trigger_data->led_cdev,
687 				      &interval,
688 				      &interval,
689 				      invert);
690 		trigger_data->last_activity = new_activity;
691 	}
692 
693 	schedule_delayed_work(&trigger_data->work,
694 			(atomic_read(&trigger_data->interval)*2));
695 }
696 
netdev_trig_activate(struct led_classdev * led_cdev)697 static int netdev_trig_activate(struct led_classdev *led_cdev)
698 {
699 	struct led_netdev_data *trigger_data;
700 	unsigned long mode = 0;
701 	struct device *dev;
702 	int rc;
703 
704 	trigger_data = kzalloc(sizeof(struct led_netdev_data), GFP_KERNEL);
705 	if (!trigger_data)
706 		return -ENOMEM;
707 
708 	mutex_init(&trigger_data->lock);
709 
710 	trigger_data->notifier.notifier_call = netdev_trig_notify;
711 	trigger_data->notifier.priority = 10;
712 
713 	INIT_DELAYED_WORK(&trigger_data->work, netdev_trig_work);
714 
715 	trigger_data->led_cdev = led_cdev;
716 	trigger_data->net_dev = NULL;
717 	trigger_data->device_name[0] = 0;
718 
719 	trigger_data->mode = 0;
720 	atomic_set(&trigger_data->interval, msecs_to_jiffies(NETDEV_LED_DEFAULT_INTERVAL));
721 	trigger_data->last_activity = 0;
722 
723 	/* Check if hw control is active by default on the LED.
724 	 * Init already enabled mode in hw control.
725 	 */
726 	if (supports_hw_control(led_cdev)) {
727 		dev = led_cdev->hw_control_get_device(led_cdev);
728 		if (dev) {
729 			const char *name = dev_name(dev);
730 
731 			trigger_data->hw_control = true;
732 			set_device_name(trigger_data, name, strlen(name));
733 
734 			rc = led_cdev->hw_control_get(led_cdev, &mode);
735 			if (!rc)
736 				trigger_data->mode = mode;
737 		}
738 	}
739 
740 	led_set_trigger_data(led_cdev, trigger_data);
741 
742 	rc = register_netdevice_notifier(&trigger_data->notifier);
743 	if (rc)
744 		kfree(trigger_data);
745 
746 	return rc;
747 }
748 
netdev_trig_deactivate(struct led_classdev * led_cdev)749 static void netdev_trig_deactivate(struct led_classdev *led_cdev)
750 {
751 	struct led_netdev_data *trigger_data = led_get_trigger_data(led_cdev);
752 
753 	unregister_netdevice_notifier(&trigger_data->notifier);
754 
755 	cancel_delayed_work_sync(&trigger_data->work);
756 
757 	dev_put(trigger_data->net_dev);
758 
759 	kfree(trigger_data);
760 }
761 
762 static struct led_trigger netdev_led_trigger = {
763 	.name = "netdev",
764 	.activate = netdev_trig_activate,
765 	.deactivate = netdev_trig_deactivate,
766 	.groups = netdev_trig_groups,
767 };
768 
769 module_led_trigger(netdev_led_trigger);
770 
771 MODULE_AUTHOR("Ben Whitten <ben.whitten@gmail.com>");
772 MODULE_AUTHOR("Oliver Jowett <oliver@opencloud.com>");
773 MODULE_DESCRIPTION("Netdev LED trigger");
774 MODULE_LICENSE("GPL v2");
775 MODULE_ALIAS("ledtrig:netdev");
776