summaryrefslogtreecommitdiffstats
path: root/drivers/leds/trigger/ledtrig-netdev.c
blob: 79719fc8a08fb495ab1ca50d7a401011d2f062d1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
// SPDX-License-Identifier: GPL-2.0
// Copyright 2017 Ben Whitten <ben.whitten@gmail.com>
// Copyright 2007 Oliver Jowett <oliver@opencloud.com>
//
// LED Kernel Netdev Trigger
//
// Toggles the LED to reflect the link and traffic state of a named net device
//
// Derived from ledtrig-timer.c which is:
//  Copyright 2005-2006 Openedhand Ltd.
//  Author: Richard Purdie <rpurdie@openedhand.com>

#include <linux/atomic.h>
#include <linux/ctype.h>
#include <linux/device.h>
#include <linux/ethtool.h>
#include <linux/init.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/leds.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/mutex.h>
#include <linux/rtnetlink.h>
#include <linux/timer.h>
#include "../leds.h"

#define NETDEV_LED_DEFAULT_INTERVAL	50

/*
 * Configurable sysfs attributes:
 *
 * device_name - network device name to monitor
 * interval - duration of LED blink, in milliseconds
 * link -  LED's normal state reflects whether the link is up
 *         (has carrier) or not
 * tx -  LED blinks on transmitted data
 * rx -  LED blinks on receive data
 *
 */

struct led_netdev_data {
	struct mutex lock;

	struct delayed_work work;
	struct notifier_block notifier;

	struct led_classdev *led_cdev;
	struct net_device *net_dev;

	char device_name[IFNAMSIZ];
	atomic_t interval;
	unsigned int last_activity;

	unsigned long mode;
	int link_speed;
	u8 duplex;

	bool carrier_link_up;
	bool hw_control;
};

static void set_baseline_state(struct led_netdev_data *trigger_data)
{
	int current_brightness;
	struct led_classdev *led_cdev = trigger_data->led_cdev;

	/* Already validated, hw control is possible with the requested mode */
	if (trigger_data->hw_control) {
		led_cdev->hw_control_set(led_cdev, trigger_data->mode);

		return;
	}

	current_brightness = led_cdev->brightness;
	if (current_brightness)
		led_cdev->blink_brightness = current_brightness;
	if (!led_cdev->blink_brightness)
		led_cdev->blink_brightness = led_cdev->max_brightness;

	if (!trigger_data->carrier_link_up) {
		led_set_brightness(led_cdev, LED_OFF);
	} else {
		bool blink_on = false;

		if (test_bit(TRIGGER_NETDEV_LINK, &trigger_data->mode))
			blink_on = true;

		if (test_bit(TRIGGER_NETDEV_LINK_10, &trigger_data->mode) &&
		    trigger_data->link_speed == SPEED_10)
			blink_on = true;

		if (test_bit(TRIGGER_NETDEV_LINK_100, &trigger_data->mode) &&
		    trigger_data->link_speed == SPEED_100)
			blink_on = true;

		if (test_bit(TRIGGER_NETDEV_LINK_1000, &trigger_data->mode) &&
		    trigger_data->link_speed == SPEED_1000)
			blink_on = true;

		if (test_bit(TRIGGER_NETDEV_HALF_DUPLEX, &trigger_data->mode) &&
		    trigger_data->duplex == DUPLEX_HALF)
			blink_on = true;

		if (test_bit(TRIGGER_NETDEV_FULL_DUPLEX, &trigger_data->mode) &&
		    trigger_data->duplex == DUPLEX_FULL)
			blink_on = true;

		if (blink_on)
			led_set_brightness(led_cdev,
					   led_cdev->blink_brightness);
		else
			led_set_brightness(led_cdev, LED_OFF);

		/* If we are looking for RX/TX start periodically
		 * checking stats
		 */
		if (test_bit(TRIGGER_NETDEV_TX, &trigger_data->mode) ||
		    test_bit(TRIGGER_NETDEV_RX, &trigger_data->mode))
			schedule_delayed_work(&trigger_data->work, 0);
	}
}

static bool supports_hw_control(struct led_classdev *led_cdev)
{
	if (!led_cdev->hw_control_get || !led_cdev->hw_control_set ||
	    !led_cdev->hw_control_is_supported)
		return false;

	return !strcmp(led_cdev->hw_control_trigger, led_cdev->trigger->name);
}

/*
 * Validate the configured netdev is the same as the one associated with
 * the LED driver in hw control.
 */
static bool validate_net_dev(struct led_classdev *led_cdev,
			     struct net_device *net_dev)
{
	struct device *dev = led_cdev->hw_control_get_device(led_cdev);
	struct net_device *ndev;

	if (!dev)
		return false;

	ndev = to_net_dev(dev);

	return ndev == net_dev;
}

static bool can_hw_control(struct led_netdev_data *trigger_data)
{
	unsigned long default_interval = msecs_to_jiffies(NETDEV_LED_DEFAULT_INTERVAL);
	unsigned int interval = atomic_read(&trigger_data->interval);
	struct led_classdev *led_cdev = trigger_data->led_cdev;
	int ret;

	if (!supports_hw_control(led_cdev))
		return false;

	/*
	 * Interval must be set to the default
	 * value. Any different value is rejected if in hw
	 * control.
	 */
	if (interval != default_interval)
		return false;

	/*
	 * net_dev must be set with hw control, otherwise no
	 * blinking can be happening and there is nothing to
	 * offloaded. Additionally, for hw control to be
	 * valid, the configured netdev must be the same as
	 * netdev associated to the LED.
	 */
	if (!validate_net_dev(led_cdev, trigger_data->net_dev))
		return false;

	/* Check if the requested mode is supported */
	ret = led_cdev->hw_control_is_supported(led_cdev, trigger_data->mode);
	/* Fall back to software blinking if not supported */
	if (ret == -EOPNOTSUPP)
		return false;
	if (ret) {
		dev_warn(led_cdev->dev,
			 "Current mode check failed with error %d\n", ret);
		return false;
	}

	return true;
}

static void get_device_state(struct led_netdev_data *trigger_data)
{
	struct ethtool_link_ksettings cmd;

	trigger_data->carrier_link_up = netif_carrier_ok(trigger_data->net_dev);
	if (!trigger_data->carrier_link_up)
		return;

	if (!__ethtool_get_link_ksettings(trigger_data->net_dev, &cmd)) {
		trigger_data->link_speed = cmd.base.speed;
		trigger_data->duplex = cmd.base.duplex;
	}
}

static ssize_t device_name_show(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
	ssize_t len;

	mutex_lock(&trigger_data->lock);
	len = sprintf(buf, "%s\n", trigger_data->device_name);
	mutex_unlock(&trigger_data->lock);

	return len;
}

static int set_device_name(struct led_netdev_data *trigger_data,
			   const char *name, size_t size)
{
	if (size >= IFNAMSIZ)
		return -EINVAL;

	cancel_delayed_work_sync(&trigger_data->work);

	/*
	 * Take RTNL lock before trigger_data lock to prevent potential
	 * deadlock with netdev notifier registration.
	 */
	rtnl_lock();
	mutex_lock(&trigger_data->lock);

	if (trigger_data->net_dev) {
		dev_put(trigger_data->net_dev);
		trigger_data->net_dev = NULL;
	}

	memcpy(trigger_data->device_name, name, size);
	trigger_data->device_name[size] = 0;
	if (size > 0 && trigger_data->device_name[size - 1] == '\n')
		trigger_data->device_name[size - 1] = 0;

	if (trigger_data->device_name[0] != 0)
		trigger_data->net_dev =
		    dev_get_by_name(&init_net, trigger_data->device_name);

	trigger_data->carrier_link_up = false;
	trigger_data->link_speed = SPEED_UNKNOWN;
	trigger_data->duplex = DUPLEX_UNKNOWN;
	if (trigger_data->net_dev)
		get_device_state(trigger_data);

	trigger_data->last_activity = 0;

	set_baseline_state(trigger_data);
	mutex_unlock(&trigger_data->lock);
	rtnl_unlock();

	return 0;
}

static ssize_t device_name_store(struct device *dev,
				 struct device_attribute *attr, const char *buf,
				 size_t size)
{
	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
	int ret;

	ret = set_device_name(trigger_data, buf, size);

	if (ret < 0)
		return ret;
	return size;
}

static DEVICE_ATTR_RW(device_name);

static ssize_t netdev_led_attr_show(struct device *dev, char *buf,
				    enum led_trigger_netdev_modes attr)
{
	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
	int bit;

	switch (attr) {
	case TRIGGER_NETDEV_LINK:
	case TRIGGER_NETDEV_LINK_10:
	case TRIGGER_NETDEV_LINK_100:
	case TRIGGER_NETDEV_LINK_1000:
	case TRIGGER_NETDEV_HALF_DUPLEX:
	case TRIGGER_NETDEV_FULL_DUPLEX:
	case TRIGGER_NETDEV_TX:
	case TRIGGER_NETDEV_RX:
		bit = attr;
		break;
	default:
		return -EINVAL;
	}

	return sprintf(buf, "%u\n", test_bit(bit, &trigger_data->mode));
}

static ssize_t netdev_led_attr_store(struct device *dev, const char *buf,
				     size_t size, enum led_trigger_netdev_modes attr)
{
	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
	unsigned long state, mode = trigger_data->mode;
	int ret;
	int bit;

	ret = kstrtoul(buf, 0, &state);
	if (ret)
		return ret;

	switch (attr) {
	case TRIGGER_NETDEV_LINK:
	case TRIGGER_NETDEV_LINK_10:
	case TRIGGER_NETDEV_LINK_100:
	case TRIGGER_NETDEV_LINK_1000:
	case TRIGGER_NETDEV_HALF_DUPLEX:
	case TRIGGER_NETDEV_FULL_DUPLEX:
	case TRIGGER_NETDEV_TX:
	case TRIGGER_NETDEV_RX:
		bit = attr;
		break;
	default:
		return -EINVAL;
	}

	if (state)
		set_bit(bit, &mode);
	else
		clear_bit(bit, &mode);

	if (test_bit(TRIGGER_NETDEV_LINK, &mode) &&
	    (test_bit(TRIGGER_NETDEV_LINK_10, &mode) ||
	     test_bit(TRIGGER_NETDEV_LINK_100, &mode) ||
	     test_bit(TRIGGER_NETDEV_LINK_1000, &mode)))
		return -EINVAL;

	cancel_delayed_work_sync(&trigger_data->work);

	trigger_data->mode = mode;
	trigger_data->hw_control = can_hw_control(trigger_data);

	set_baseline_state(trigger_data);

	return size;
}

#define DEFINE_NETDEV_TRIGGER(trigger_name, trigger) \
	static ssize_t trigger_name##_show(struct device *dev, \
		struct device_attribute *attr, char *buf) \
	{ \
		return netdev_led_attr_show(dev, buf, trigger); \
	} \
	static ssize_t trigger_name##_store(struct device *dev, \
		struct device_attribute *attr, const char *buf, size_t size) \
	{ \
		return netdev_led_attr_store(dev, buf, size, trigger); \
	} \
	static DEVICE_ATTR_RW(trigger_name)

DEFINE_NETDEV_TRIGGER(link, TRIGGER_NETDEV_LINK);
DEFINE_NETDEV_TRIGGER(link_10, TRIGGER_NETDEV_LINK_10);
DEFINE_NETDEV_TRIGGER(link_100, TRIGGER_NETDEV_LINK_100);
DEFINE_NETDEV_TRIGGER(link_1000, TRIGGER_NETDEV_LINK_1000);
DEFINE_NETDEV_TRIGGER(half_duplex, TRIGGER_NETDEV_HALF_DUPLEX);
DEFINE_NETDEV_TRIGGER(full_duplex, TRIGGER_NETDEV_FULL_DUPLEX);
DEFINE_NETDEV_TRIGGER(tx, TRIGGER_NETDEV_TX);
DEFINE_NETDEV_TRIGGER(rx, TRIGGER_NETDEV_RX);

static ssize_t interval_show(struct device *dev,
			     struct device_attribute *attr, char *buf)
{
	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);

	return sprintf(buf, "%u\n",
		       jiffies_to_msecs(atomic_read(&trigger_data->interval)));
}

static ssize_t interval_store(struct device *dev,
			      struct device_attribute *attr, const char *buf,
			      size_t size)
{
	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
	unsigned long value;
	int ret;

	if (trigger_data->hw_control)
		return -EINVAL;

	ret = kstrtoul(buf, 0, &value);
	if (ret)
		return ret;

	/* impose some basic bounds on the timer interval */
	if (value >= 5 && value <= 10000) {
		cancel_delayed_work_sync(&trigger_data->work);

		atomic_set(&trigger_data->interval, msecs_to_jiffies(value));
		set_baseline_state(trigger_data);	/* resets timer */
	}

	return size;
}

static DEVICE_ATTR_RW(interval);

static ssize_t offloaded_show(struct device *dev,
			      struct device_attribute *attr, char *buf)
{
	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);

	return sprintf(buf, "%d\n", trigger_data->hw_control);
}

static DEVICE_ATTR_RO(offloaded);

static struct attribute *netdev_trig_attrs[] = {
	&dev_attr_device_name.attr,
	&dev_attr_link.attr,
	&dev_attr_link_10.attr,
	&dev_attr_link_100.attr,
	&dev_attr_link_1000.attr,
	&dev_attr_full_duplex.attr,
	&dev_attr_half_duplex.attr,
	&dev_attr_rx.attr,
	&dev_attr_tx.attr,
	&dev_attr_interval.attr,
	&dev_attr_offloaded.attr,
	NULL
};
ATTRIBUTE_GROUPS(netdev_trig);

static int netdev_trig_notify(struct notifier_block *nb,
			      unsigned long evt, void *dv)
{
	struct net_device *dev =
		netdev_notifier_info_to_dev((struct netdev_notifier_info *)dv);
	struct led_netdev_data *trigger_data =
		container_of(nb, struct led_netdev_data, notifier);

	if (evt != NETDEV_UP && evt != NETDEV_DOWN && evt != NETDEV_CHANGE
	    && evt != NETDEV_REGISTER && evt != NETDEV_UNREGISTER
	    && evt != NETDEV_CHANGENAME)
		return NOTIFY_DONE;

	if (!(dev == trigger_data->net_dev ||
	      (evt == NETDEV_CHANGENAME && !strcmp(dev->name, trigger_data->device_name)) ||
	      (evt == NETDEV_REGISTER && !strcmp(dev->name, trigger_data->device_name))))
		return NOTIFY_DONE;

	cancel_delayed_work_sync(&trigger_data->work);

	mutex_lock(&trigger_data->lock);

	trigger_data->carrier_link_up = false;
	trigger_data->link_speed = SPEED_UNKNOWN;
	trigger_data->duplex = DUPLEX_UNKNOWN;
	switch (evt) {
	case NETDEV_CHANGENAME:
	case NETDEV_REGISTER:
		dev_put(trigger_data->net_dev);
		dev_hold(dev);
		trigger_data->net_dev = dev;
		if (evt == NETDEV_CHANGENAME)
			get_device_state(trigger_data);
		break;
	case NETDEV_UNREGISTER:
		dev_put(trigger_data->net_dev);
		trigger_data->net_dev = NULL;
		break;
	case NETDEV_UP:
	case NETDEV_CHANGE:
		get_device_state(trigger_data);
		break;
	}

	set_baseline_state(trigger_data);

	mutex_unlock(&trigger_data->lock);

	return NOTIFY_DONE;
}

/* here's the real work! */
static void netdev_trig_work(struct work_struct *work)
{
	struct led_netdev_data *trigger_data =
		container_of(work, struct led_netdev_data, work.work);
	struct rtnl_link_stats64 *dev_stats;
	unsigned int new_activity;
	struct rtnl_link_stats64 temp;
	unsigned long interval;
	int invert;

	/* If we dont have a device, insure we are off */
	if (!trigger_data->net_dev) {
		led_set_brightness(trigger_data->led_cdev, LED_OFF);
		return;
	}

	/* If we are not looking for RX/TX then return  */
	if (!test_bit(TRIGGER_NETDEV_TX, &trigger_data->mode) &&
	    !test_bit(TRIGGER_NETDEV_RX, &trigger_data->mode))
		return;

	dev_stats = dev_get_stats(trigger_data->net_dev, &temp);
	new_activity =
	    (test_bit(TRIGGER_NETDEV_TX, &trigger_data->mode) ?
		dev_stats->tx_packets : 0) +
	    (test_bit(TRIGGER_NETDEV_RX, &trigger_data->mode) ?
		dev_stats->rx_packets : 0);

	if (trigger_data->last_activity != new_activity) {
		led_stop_software_blink(trigger_data->led_cdev);

		invert = test_bit(TRIGGER_NETDEV_LINK, &trigger_data->mode) ||
			 test_bit(TRIGGER_NETDEV_LINK_10, &trigger_data->mode) ||
			 test_bit(TRIGGER_NETDEV_LINK_100, &trigger_data->mode) ||
			 test_bit(TRIGGER_NETDEV_LINK_1000, &trigger_data->mode) ||
			 test_bit(TRIGGER_NETDEV_HALF_DUPLEX, &trigger_data->mode) ||
			 test_bit(TRIGGER_NETDEV_FULL_DUPLEX, &trigger_data->mode);
		interval = jiffies_to_msecs(
				atomic_read(&trigger_data->interval));
		/* base state is ON (link present) */
		led_blink_set_oneshot(trigger_data->led_cdev,
				      &interval,
				      &interval,
				      invert);
		trigger_data->last_activity = new_activity;
	}

	schedule_delayed_work(&trigger_data->work,
			(atomic_read(&trigger_data->interval)*2));
}

static int netdev_trig_activate(struct led_classdev *led_cdev)
{
	struct led_netdev_data *trigger_data;
	unsigned long mode = 0;
	struct device *dev;
	int rc;

	trigger_data = kzalloc(sizeof(struct led_netdev_data), GFP_KERNEL);
	if (!trigger_data)
		return -ENOMEM;

	mutex_init(&trigger_data->lock);

	trigger_data->notifier.notifier_call = netdev_trig_notify;
	trigger_data->notifier.priority = 10;

	INIT_DELAYED_WORK(&trigger_data->work, netdev_trig_work);

	trigger_data->led_cdev = led_cdev;
	trigger_data->net_dev = NULL;
	trigger_data->device_name[0] = 0;

	trigger_data->mode = 0;
	atomic_set(&trigger_data->interval, msecs_to_jiffies(NETDEV_LED_DEFAULT_INTERVAL));
	trigger_data->last_activity = 0;

	/* Check if hw control is active by default on the LED.
	 * Init already enabled mode in hw control.
	 */
	if (supports_hw_control(led_cdev)) {
		dev = led_cdev->hw_control_get_device(led_cdev);
		if (dev) {
			const char *name = dev_name(dev);

			set_device_name(trigger_data, name, strlen(name));
			trigger_data->hw_control = true;

			rc = led_cdev->hw_control_get(led_cdev, &mode);
			if (!rc)
				trigger_data->mode = mode;
		}
	}

	led_set_trigger_data(led_cdev, trigger_data);

	rc = register_netdevice_notifier(&trigger_data->notifier);
	if (rc)
		kfree(trigger_data);

	return rc;
}

static void netdev_trig_deactivate(struct led_classdev *led_cdev)
{
	struct led_netdev_data *trigger_data = led_get_trigger_data(led_cdev);

	unregister_netdevice_notifier(&trigger_data->notifier);

	cancel_delayed_work_sync(&trigger_data->work);

	led_set_brightness(led_cdev, LED_OFF);

	dev_put(trigger_data->net_dev);

	kfree(trigger_data);
}

static struct led_trigger netdev_led_trigger = {
	.name = "netdev",
	.activate = netdev_trig_activate,
	.deactivate = netdev_trig_deactivate,
	.groups = netdev_trig_groups,
};

module_led_trigger(netdev_led_trigger);

MODULE_AUTHOR("Ben Whitten <ben.whitten@gmail.com>");
MODULE_AUTHOR("Oliver Jowett <oliver@opencloud.com>");
MODULE_DESCRIPTION("Netdev LED trigger");
MODULE_LICENSE("GPL v2");