aboutsummaryrefslogtreecommitdiff
path: root/drivers/leds/leds-netxbig.c
blob: 77213b79f84d95d709709e8a24e052aa0eb750c1 (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
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * leds-netxbig.c - Driver for the 2Big and 5Big Network series LEDs
 *
 * Copyright (C) 2010 LaCie
 *
 * Author: Simon Guinot <sguinot@lacie.com>
 */

#include <linux/module.h>
#include <linux/irq.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/platform_device.h>
#include <linux/gpio/consumer.h>
#include <linux/leds.h>
#include <linux/of.h>
#include <linux/of_platform.h>

struct netxbig_gpio_ext {
	struct gpio_desc **addr;
	int		num_addr;
	struct gpio_desc **data;
	int		num_data;
	struct gpio_desc *enable;
};

enum netxbig_led_mode {
	NETXBIG_LED_OFF,
	NETXBIG_LED_ON,
	NETXBIG_LED_SATA,
	NETXBIG_LED_TIMER1,
	NETXBIG_LED_TIMER2,
	NETXBIG_LED_MODE_NUM,
};

#define NETXBIG_LED_INVALID_MODE NETXBIG_LED_MODE_NUM

struct netxbig_led_timer {
	unsigned long		delay_on;
	unsigned long		delay_off;
	enum netxbig_led_mode	mode;
};

struct netxbig_led {
	const char	*name;
	const char	*default_trigger;
	int		mode_addr;
	int		*mode_val;
	int		bright_addr;
	int		bright_max;
};

struct netxbig_led_platform_data {
	struct netxbig_gpio_ext	*gpio_ext;
	struct netxbig_led_timer *timer;
	int			num_timer;
	struct netxbig_led	*leds;
	int			num_leds;
};

/*
 * GPIO extension bus.
 */

static DEFINE_SPINLOCK(gpio_ext_lock);

static void gpio_ext_set_addr(struct netxbig_gpio_ext *gpio_ext, int addr)
{
	int pin;

	for (pin = 0; pin < gpio_ext->num_addr; pin++)
		gpiod_set_value(gpio_ext->addr[pin], (addr >> pin) & 1);
}

static void gpio_ext_set_data(struct netxbig_gpio_ext *gpio_ext, int data)
{
	int pin;

	for (pin = 0; pin < gpio_ext->num_data; pin++)
		gpiod_set_value(gpio_ext->data[pin], (data >> pin) & 1);
}

static void gpio_ext_enable_select(struct netxbig_gpio_ext *gpio_ext)
{
	/* Enable select is done on the raising edge. */
	gpiod_set_value(gpio_ext->enable, 0);
	gpiod_set_value(gpio_ext->enable, 1);
}

static void gpio_ext_set_value(struct netxbig_gpio_ext *gpio_ext,
			       int addr, int value)
{
	unsigned long flags;

	spin_lock_irqsave(&gpio_ext_lock, flags);
	gpio_ext_set_addr(gpio_ext, addr);
	gpio_ext_set_data(gpio_ext, value);
	gpio_ext_enable_select(gpio_ext);
	spin_unlock_irqrestore(&gpio_ext_lock, flags);
}

/*
 * Class LED driver.
 */

struct netxbig_led_data {
	struct netxbig_gpio_ext	*gpio_ext;
	struct led_classdev	cdev;
	int			mode_addr;
	int			*mode_val;
	int			bright_addr;
	struct			netxbig_led_timer *timer;
	int			num_timer;
	enum netxbig_led_mode	mode;
	int			sata;
	spinlock_t		lock;
};

static int netxbig_led_get_timer_mode(enum netxbig_led_mode *mode,
				      unsigned long delay_on,
				      unsigned long delay_off,
				      struct netxbig_led_timer *timer,
				      int num_timer)
{
	int i;

	for (i = 0; i < num_timer; i++) {
		if (timer[i].delay_on == delay_on &&
		    timer[i].delay_off == delay_off) {
			*mode = timer[i].mode;
			return 0;
		}
	}
	return -EINVAL;
}

static int netxbig_led_blink_set(struct led_classdev *led_cdev,
				 unsigned long *delay_on,
				 unsigned long *delay_off)
{
	struct netxbig_led_data *led_dat =
		container_of(led_cdev, struct netxbig_led_data, cdev);
	enum netxbig_led_mode mode;
	int mode_val;
	int ret;

	/* Look for a LED mode with the requested timer frequency. */
	ret = netxbig_led_get_timer_mode(&mode, *delay_on, *delay_off,
					 led_dat->timer, led_dat->num_timer);
	if (ret < 0)
		return ret;

	mode_val = led_dat->mode_val[mode];
	if (mode_val == NETXBIG_LED_INVALID_MODE)
		return -EINVAL;

	spin_lock_irq(&led_dat->lock);

	gpio_ext_set_value(led_dat->gpio_ext, led_dat->mode_addr, mode_val);
	led_dat->mode = mode;

	spin_unlock_irq(&led_dat->lock);

	return 0;
}

static void netxbig_led_set(struct led_classdev *led_cdev,
			    enum led_brightness value)
{
	struct netxbig_led_data *led_dat =
		container_of(led_cdev, struct netxbig_led_data, cdev);
	enum netxbig_led_mode mode;
	int mode_val;
	int set_brightness = 1;
	unsigned long flags;

	spin_lock_irqsave(&led_dat->lock, flags);

	if (value == LED_OFF) {
		mode = NETXBIG_LED_OFF;
		set_brightness = 0;
	} else {
		if (led_dat->sata)
			mode = NETXBIG_LED_SATA;
		else if (led_dat->mode == NETXBIG_LED_OFF)
			mode = NETXBIG_LED_ON;
		else /* Keep 'timer' mode. */
			mode = led_dat->mode;
	}
	mode_val = led_dat->mode_val[mode];

	gpio_ext_set_value(led_dat->gpio_ext, led_dat->mode_addr, mode_val);
	led_dat->mode = mode;
	/*
	 * Note that the brightness register is shared between all the
	 * SATA LEDs. So, change the brightness setting for a single
	 * SATA LED will affect all the others.
	 */
	if (set_brightness)
		gpio_ext_set_value(led_dat->gpio_ext,
				   led_dat->bright_addr, value);

	spin_unlock_irqrestore(&led_dat->lock, flags);
}

static ssize_t sata_store(struct device *dev,
			  struct device_attribute *attr,
			  const char *buff, size_t count)
{
	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	struct netxbig_led_data *led_dat =
		container_of(led_cdev, struct netxbig_led_data, cdev);
	unsigned long enable;
	enum netxbig_led_mode mode;
	int mode_val;
	int ret;

	ret = kstrtoul(buff, 10, &enable);
	if (ret < 0)
		return ret;

	enable = !!enable;

	spin_lock_irq(&led_dat->lock);

	if (led_dat->sata == enable) {
		ret = count;
		goto exit_unlock;
	}

	if (led_dat->mode != NETXBIG_LED_ON &&
	    led_dat->mode != NETXBIG_LED_SATA)
		mode = led_dat->mode; /* Keep modes 'off' and 'timer'. */
	else if (enable)
		mode = NETXBIG_LED_SATA;
	else
		mode = NETXBIG_LED_ON;

	mode_val = led_dat->mode_val[mode];
	if (mode_val == NETXBIG_LED_INVALID_MODE) {
		ret = -EINVAL;
		goto exit_unlock;
	}

	gpio_ext_set_value(led_dat->gpio_ext, led_dat->mode_addr, mode_val);
	led_dat->mode = mode;
	led_dat->sata = enable;

	ret = count;

exit_unlock:
	spin_unlock_irq(&led_dat->lock);

	return ret;
}

static ssize_t sata_show(struct device *dev,
			 struct device_attribute *attr, char *buf)
{
	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	struct netxbig_led_data *led_dat =
		container_of(led_cdev, struct netxbig_led_data, cdev);

	return sprintf(buf, "%d\n", led_dat->sata);
}

static DEVICE_ATTR_RW(sata);

static struct attribute *netxbig_led_attrs[] = {
	&dev_attr_sata.attr,
	NULL
};
ATTRIBUTE_GROUPS(netxbig_led);

static int create_netxbig_led(struct platform_device *pdev,
			      struct netxbig_led_platform_data *pdata,
			      struct netxbig_led_data *led_dat,
			      const struct netxbig_led *template)
{
	spin_lock_init(&led_dat->lock);
	led_dat->gpio_ext = pdata->gpio_ext;
	led_dat->cdev.name = template->name;
	led_dat->cdev.default_trigger = template->default_trigger;
	led_dat->cdev.blink_set = netxbig_led_blink_set;
	led_dat->cdev.brightness_set = netxbig_led_set;
	/*
	 * Because the GPIO extension bus don't allow to read registers
	 * value, there is no way to probe the LED initial state.
	 * So, the initial sysfs LED value for the "brightness" and "sata"
	 * attributes are inconsistent.
	 *
	 * Note that the initial LED state can't be reconfigured.
	 * The reason is that the LED behaviour must stay uniform during
	 * the whole boot process (bootloader+linux).
	 */
	led_dat->sata = 0;
	led_dat->cdev.brightness = LED_OFF;
	led_dat->cdev.max_brightness = template->bright_max;
	led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
	led_dat->mode_addr = template->mode_addr;
	led_dat->mode_val = template->mode_val;
	led_dat->bright_addr = template->bright_addr;
	led_dat->timer = pdata->timer;
	led_dat->num_timer = pdata->num_timer;
	/*
	 * If available, expose the SATA activity blink capability through
	 * a "sata" sysfs attribute.
	 */
	if (led_dat->mode_val[NETXBIG_LED_SATA] != NETXBIG_LED_INVALID_MODE)
		led_dat->cdev.groups = netxbig_led_groups;

	return devm_led_classdev_register(&pdev->dev, &led_dat->cdev);
}

/**
 * netxbig_gpio_ext_remove() - Clean up GPIO extension data
 * @data: managed resource data to clean up
 *
 * Since we pick GPIO descriptors from another device than the device our
 * driver is probing to, we need to register a specific callback to free
 * these up using managed resources.
 */
static void netxbig_gpio_ext_remove(void *data)
{
	struct netxbig_gpio_ext *gpio_ext = data;
	int i;

	for (i = 0; i < gpio_ext->num_addr; i++)
		gpiod_put(gpio_ext->addr[i]);
	for (i = 0; i < gpio_ext->num_data; i++)
		gpiod_put(gpio_ext->data[i]);
	gpiod_put(gpio_ext->enable);
}

/**
 * netxbig_gpio_ext_get() - Obtain GPIO extension device data
 * @dev: main LED device
 * @gpio_ext_dev: the GPIO extension device
 * @gpio_ext: the data structure holding the GPIO extension data
 *
 * This function walks the subdevice that only contain GPIO line
 * handles in the device tree and obtains the GPIO descriptors from that
 * device.
 */
static int netxbig_gpio_ext_get(struct device *dev,
				struct device *gpio_ext_dev,
				struct netxbig_gpio_ext *gpio_ext)
{
	struct gpio_desc **addr, **data;
	int num_addr, num_data;
	struct gpio_desc *gpiod;
	int ret;
	int i;

	ret = gpiod_count(gpio_ext_dev, "addr");
	if (ret < 0) {
		dev_err(dev,
			"Failed to count GPIOs in DT property addr-gpios\n");
		return ret;
	}
	num_addr = ret;
	addr = devm_kcalloc(dev, num_addr, sizeof(*addr), GFP_KERNEL);
	if (!addr)
		return -ENOMEM;

	/*
	 * We cannot use devm_ managed resources with these GPIO descriptors
	 * since they are associated with the "GPIO extension device" which
	 * does not probe any driver. The device tree parser will however
	 * populate a platform device for it so we can anyway obtain the
	 * GPIO descriptors from the device.
	 */
	for (i = 0; i < num_addr; i++) {
		gpiod = gpiod_get_index(gpio_ext_dev, "addr", i,
					GPIOD_OUT_LOW);
		if (IS_ERR(gpiod))
			return PTR_ERR(gpiod);
		gpiod_set_consumer_name(gpiod, "GPIO extension addr");
		addr[i] = gpiod;
	}
	gpio_ext->addr = addr;
	gpio_ext->num_addr = num_addr;

	ret = gpiod_count(gpio_ext_dev, "data");
	if (ret < 0) {
		dev_err(dev,
			"Failed to count GPIOs in DT property data-gpios\n");
		return ret;
	}
	num_data = ret;
	data = devm_kcalloc(dev, num_data, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	for (i = 0; i < num_data; i++) {
		gpiod = gpiod_get_index(gpio_ext_dev, "data", i,
					GPIOD_OUT_LOW);
		if (IS_ERR(gpiod))
			return PTR_ERR(gpiod);
		gpiod_set_consumer_name(gpiod, "GPIO extension data");
		data[i] = gpiod;
	}
	gpio_ext->data = data;
	gpio_ext->num_data = num_data;

	gpiod = gpiod_get(gpio_ext_dev, "enable", GPIOD_OUT_LOW);
	if (IS_ERR(gpiod)) {
		dev_err(dev,
			"Failed to get GPIO from DT property enable-gpio\n");
		return PTR_ERR(gpiod);
	}
	gpiod_set_consumer_name(gpiod, "GPIO extension enable");
	gpio_ext->enable = gpiod;

	return devm_add_action_or_reset(dev, netxbig_gpio_ext_remove, gpio_ext);
}

static int netxbig_leds_get_of_pdata(struct device *dev,
				     struct netxbig_led_platform_data *pdata)
{
	struct device_node *np = dev_of_node(dev);
	struct device_node *gpio_ext_np;
	struct platform_device *gpio_ext_pdev;
	struct device *gpio_ext_dev;
	struct device_node *child;
	struct netxbig_gpio_ext *gpio_ext;
	struct netxbig_led_timer *timers;
	struct netxbig_led *leds, *led;
	int num_timers;
	int num_leds = 0;
	int ret;
	int i;

	/* GPIO extension */
	gpio_ext_np = of_parse_phandle(np, "gpio-ext", 0);
	if (!gpio_ext_np) {
		dev_err(dev, "Failed to get DT handle gpio-ext\n");
		return -EINVAL;
	}
	gpio_ext_pdev = of_find_device_by_node(gpio_ext_np);
	if (!gpio_ext_pdev) {
		dev_err(dev, "Failed to find platform device for gpio-ext\n");
		return -ENODEV;
	}
	gpio_ext_dev = &gpio_ext_pdev->dev;

	gpio_ext = devm_kzalloc(dev, sizeof(*gpio_ext), GFP_KERNEL);
	if (!gpio_ext) {
		of_node_put(gpio_ext_np);
		ret = -ENOMEM;
		goto put_device;
	}
	ret = netxbig_gpio_ext_get(dev, gpio_ext_dev, gpio_ext);
	of_node_put(gpio_ext_np);
	if (ret)
		goto put_device;
	pdata->gpio_ext = gpio_ext;

	/* Timers (optional) */
	ret = of_property_count_u32_elems(np, "timers");
	if (ret > 0) {
		if (ret % 3) {
			ret = -EINVAL;
			goto put_device;
		}

		num_timers = ret / 3;
		timers = devm_kcalloc(dev, num_timers, sizeof(*timers),
				      GFP_KERNEL);
		if (!timers) {
			ret = -ENOMEM;
			goto put_device;
		}
		for (i = 0; i < num_timers; i++) {
			u32 tmp;

			of_property_read_u32_index(np, "timers", 3 * i,
						   &timers[i].mode);
			if (timers[i].mode >= NETXBIG_LED_MODE_NUM) {
				ret = -EINVAL;
				goto put_device;
			}
			of_property_read_u32_index(np, "timers",
						   3 * i + 1, &tmp);
			timers[i].delay_on = tmp;
			of_property_read_u32_index(np, "timers",
						   3 * i + 2, &tmp);
			timers[i].delay_off = tmp;
		}
		pdata->timer = timers;
		pdata->num_timer = num_timers;
	}

	/* LEDs */
	num_leds = of_get_available_child_count(np);
	if (!num_leds) {
		dev_err(dev, "No LED subnodes found in DT\n");
		ret = -ENODEV;
		goto put_device;
	}

	leds = devm_kcalloc(dev, num_leds, sizeof(*leds), GFP_KERNEL);
	if (!leds) {
		ret = -ENOMEM;
		goto put_device;
	}

	led = leds;
	for_each_available_child_of_node(np, child) {
		const char *string;
		int *mode_val;
		int num_modes;

		ret = of_property_read_u32(child, "mode-addr",
					   &led->mode_addr);
		if (ret)
			goto err_node_put;

		ret = of_property_read_u32(child, "bright-addr",
					   &led->bright_addr);
		if (ret)
			goto err_node_put;

		ret = of_property_read_u32(child, "max-brightness",
					   &led->bright_max);
		if (ret)
			goto err_node_put;

		mode_val =
			devm_kcalloc(dev,
				     NETXBIG_LED_MODE_NUM, sizeof(*mode_val),
				     GFP_KERNEL);
		if (!mode_val) {
			ret = -ENOMEM;
			goto err_node_put;
		}

		for (i = 0; i < NETXBIG_LED_MODE_NUM; i++)
			mode_val[i] = NETXBIG_LED_INVALID_MODE;

		ret = of_property_count_u32_elems(child, "mode-val");
		if (ret < 0 || ret % 2) {
			ret = -EINVAL;
			goto err_node_put;
		}
		num_modes = ret / 2;
		if (num_modes > NETXBIG_LED_MODE_NUM) {
			ret = -EINVAL;
			goto err_node_put;
		}

		for (i = 0; i < num_modes; i++) {
			int mode;
			int val;

			of_property_read_u32_index(child,
						   "mode-val", 2 * i, &mode);
			of_property_read_u32_index(child,
						   "mode-val", 2 * i + 1, &val);
			if (mode >= NETXBIG_LED_MODE_NUM) {
				ret = -EINVAL;
				goto err_node_put;
			}
			mode_val[mode] = val;
		}
		led->mode_val = mode_val;

		if (!of_property_read_string(child, "label", &string))
			led->name = string;
		else
			led->name = child->name;

		if (!of_property_read_string(child,
					     "linux,default-trigger", &string))
			led->default_trigger = string;

		led++;
	}

	pdata->leds = leds;
	pdata->num_leds = num_leds;

	return 0;

err_node_put:
	of_node_put(child);
put_device:
	put_device(gpio_ext_dev);
	return ret;
}

static const struct of_device_id of_netxbig_leds_match[] = {
	{ .compatible = "lacie,netxbig-leds", },
	{},
};
MODULE_DEVICE_TABLE(of, of_netxbig_leds_match);

static int netxbig_led_probe(struct platform_device *pdev)
{
	struct netxbig_led_platform_data *pdata;
	struct netxbig_led_data *leds_data;
	int i;
	int ret;

	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata)
		return -ENOMEM;
	ret = netxbig_leds_get_of_pdata(&pdev->dev, pdata);
	if (ret)
		return ret;

	leds_data = devm_kcalloc(&pdev->dev,
				 pdata->num_leds, sizeof(*leds_data),
				 GFP_KERNEL);
	if (!leds_data)
		return -ENOMEM;

	for (i = 0; i < pdata->num_leds; i++) {
		ret = create_netxbig_led(pdev, pdata,
					 &leds_data[i], &pdata->leds[i]);
		if (ret < 0)
			return ret;
	}

	return 0;
}

static struct platform_driver netxbig_led_driver = {
	.probe		= netxbig_led_probe,
	.driver		= {
		.name		= "leds-netxbig",
		.of_match_table	= of_netxbig_leds_match,
	},
};

module_platform_driver(netxbig_led_driver);

MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>");
MODULE_DESCRIPTION("LED driver for LaCie xBig Network boards");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:leds-netxbig");