1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * leds-netxbig.c - Driver for the 2Big and 5Big Network series LEDs
4 *
5 * Copyright (C) 2010 LaCie
6 *
7 * Author: Simon Guinot <sguinot@lacie.com>
8 */
9
10 #include <linux/module.h>
11 #include <linux/irq.h>
12 #include <linux/slab.h>
13 #include <linux/spinlock.h>
14 #include <linux/platform_device.h>
15 #include <linux/gpio.h>
16 #include <linux/of_gpio.h>
17 #include <linux/leds.h>
18
19 struct netxbig_gpio_ext {
20 unsigned int *addr;
21 int num_addr;
22 unsigned int *data;
23 int num_data;
24 unsigned int enable;
25 };
26
27 enum netxbig_led_mode {
28 NETXBIG_LED_OFF,
29 NETXBIG_LED_ON,
30 NETXBIG_LED_SATA,
31 NETXBIG_LED_TIMER1,
32 NETXBIG_LED_TIMER2,
33 NETXBIG_LED_MODE_NUM,
34 };
35
36 #define NETXBIG_LED_INVALID_MODE NETXBIG_LED_MODE_NUM
37
38 struct netxbig_led_timer {
39 unsigned long delay_on;
40 unsigned long delay_off;
41 enum netxbig_led_mode mode;
42 };
43
44 struct netxbig_led {
45 const char *name;
46 const char *default_trigger;
47 int mode_addr;
48 int *mode_val;
49 int bright_addr;
50 int bright_max;
51 };
52
53 struct netxbig_led_platform_data {
54 struct netxbig_gpio_ext *gpio_ext;
55 struct netxbig_led_timer *timer;
56 int num_timer;
57 struct netxbig_led *leds;
58 int num_leds;
59 };
60
61 /*
62 * GPIO extension bus.
63 */
64
65 static DEFINE_SPINLOCK(gpio_ext_lock);
66
gpio_ext_set_addr(struct netxbig_gpio_ext * gpio_ext,int addr)67 static void gpio_ext_set_addr(struct netxbig_gpio_ext *gpio_ext, int addr)
68 {
69 int pin;
70
71 for (pin = 0; pin < gpio_ext->num_addr; pin++)
72 gpio_set_value(gpio_ext->addr[pin], (addr >> pin) & 1);
73 }
74
gpio_ext_set_data(struct netxbig_gpio_ext * gpio_ext,int data)75 static void gpio_ext_set_data(struct netxbig_gpio_ext *gpio_ext, int data)
76 {
77 int pin;
78
79 for (pin = 0; pin < gpio_ext->num_data; pin++)
80 gpio_set_value(gpio_ext->data[pin], (data >> pin) & 1);
81 }
82
gpio_ext_enable_select(struct netxbig_gpio_ext * gpio_ext)83 static void gpio_ext_enable_select(struct netxbig_gpio_ext *gpio_ext)
84 {
85 /* Enable select is done on the raising edge. */
86 gpio_set_value(gpio_ext->enable, 0);
87 gpio_set_value(gpio_ext->enable, 1);
88 }
89
gpio_ext_set_value(struct netxbig_gpio_ext * gpio_ext,int addr,int value)90 static void gpio_ext_set_value(struct netxbig_gpio_ext *gpio_ext,
91 int addr, int value)
92 {
93 unsigned long flags;
94
95 spin_lock_irqsave(&gpio_ext_lock, flags);
96 gpio_ext_set_addr(gpio_ext, addr);
97 gpio_ext_set_data(gpio_ext, value);
98 gpio_ext_enable_select(gpio_ext);
99 spin_unlock_irqrestore(&gpio_ext_lock, flags);
100 }
101
gpio_ext_init(struct platform_device * pdev,struct netxbig_gpio_ext * gpio_ext)102 static int gpio_ext_init(struct platform_device *pdev,
103 struct netxbig_gpio_ext *gpio_ext)
104 {
105 int err;
106 int i;
107
108 if (unlikely(!gpio_ext))
109 return -EINVAL;
110
111 /* Configure address GPIOs. */
112 for (i = 0; i < gpio_ext->num_addr; i++) {
113 err = devm_gpio_request_one(&pdev->dev, gpio_ext->addr[i],
114 GPIOF_OUT_INIT_LOW,
115 "GPIO extension addr");
116 if (err)
117 return err;
118 }
119 /* Configure data GPIOs. */
120 for (i = 0; i < gpio_ext->num_data; i++) {
121 err = devm_gpio_request_one(&pdev->dev, gpio_ext->data[i],
122 GPIOF_OUT_INIT_LOW,
123 "GPIO extension data");
124 if (err)
125 return err;
126 }
127 /* Configure "enable select" GPIO. */
128 err = devm_gpio_request_one(&pdev->dev, gpio_ext->enable,
129 GPIOF_OUT_INIT_LOW,
130 "GPIO extension enable");
131 if (err)
132 return err;
133
134 return 0;
135 }
136
137 /*
138 * Class LED driver.
139 */
140
141 struct netxbig_led_data {
142 struct netxbig_gpio_ext *gpio_ext;
143 struct led_classdev cdev;
144 int mode_addr;
145 int *mode_val;
146 int bright_addr;
147 struct netxbig_led_timer *timer;
148 int num_timer;
149 enum netxbig_led_mode mode;
150 int sata;
151 spinlock_t lock;
152 };
153
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)154 static int netxbig_led_get_timer_mode(enum netxbig_led_mode *mode,
155 unsigned long delay_on,
156 unsigned long delay_off,
157 struct netxbig_led_timer *timer,
158 int num_timer)
159 {
160 int i;
161
162 for (i = 0; i < num_timer; i++) {
163 if (timer[i].delay_on == delay_on &&
164 timer[i].delay_off == delay_off) {
165 *mode = timer[i].mode;
166 return 0;
167 }
168 }
169 return -EINVAL;
170 }
171
netxbig_led_blink_set(struct led_classdev * led_cdev,unsigned long * delay_on,unsigned long * delay_off)172 static int netxbig_led_blink_set(struct led_classdev *led_cdev,
173 unsigned long *delay_on,
174 unsigned long *delay_off)
175 {
176 struct netxbig_led_data *led_dat =
177 container_of(led_cdev, struct netxbig_led_data, cdev);
178 enum netxbig_led_mode mode;
179 int mode_val;
180 int ret;
181
182 /* Look for a LED mode with the requested timer frequency. */
183 ret = netxbig_led_get_timer_mode(&mode, *delay_on, *delay_off,
184 led_dat->timer, led_dat->num_timer);
185 if (ret < 0)
186 return ret;
187
188 mode_val = led_dat->mode_val[mode];
189 if (mode_val == NETXBIG_LED_INVALID_MODE)
190 return -EINVAL;
191
192 spin_lock_irq(&led_dat->lock);
193
194 gpio_ext_set_value(led_dat->gpio_ext, led_dat->mode_addr, mode_val);
195 led_dat->mode = mode;
196
197 spin_unlock_irq(&led_dat->lock);
198
199 return 0;
200 }
201
netxbig_led_set(struct led_classdev * led_cdev,enum led_brightness value)202 static void netxbig_led_set(struct led_classdev *led_cdev,
203 enum led_brightness value)
204 {
205 struct netxbig_led_data *led_dat =
206 container_of(led_cdev, struct netxbig_led_data, cdev);
207 enum netxbig_led_mode mode;
208 int mode_val;
209 int set_brightness = 1;
210 unsigned long flags;
211
212 spin_lock_irqsave(&led_dat->lock, flags);
213
214 if (value == LED_OFF) {
215 mode = NETXBIG_LED_OFF;
216 set_brightness = 0;
217 } else {
218 if (led_dat->sata)
219 mode = NETXBIG_LED_SATA;
220 else if (led_dat->mode == NETXBIG_LED_OFF)
221 mode = NETXBIG_LED_ON;
222 else /* Keep 'timer' mode. */
223 mode = led_dat->mode;
224 }
225 mode_val = led_dat->mode_val[mode];
226
227 gpio_ext_set_value(led_dat->gpio_ext, led_dat->mode_addr, mode_val);
228 led_dat->mode = mode;
229 /*
230 * Note that the brightness register is shared between all the
231 * SATA LEDs. So, change the brightness setting for a single
232 * SATA LED will affect all the others.
233 */
234 if (set_brightness)
235 gpio_ext_set_value(led_dat->gpio_ext,
236 led_dat->bright_addr, value);
237
238 spin_unlock_irqrestore(&led_dat->lock, flags);
239 }
240
netxbig_led_sata_store(struct device * dev,struct device_attribute * attr,const char * buff,size_t count)241 static ssize_t netxbig_led_sata_store(struct device *dev,
242 struct device_attribute *attr,
243 const char *buff, size_t count)
244 {
245 struct led_classdev *led_cdev = dev_get_drvdata(dev);
246 struct netxbig_led_data *led_dat =
247 container_of(led_cdev, struct netxbig_led_data, cdev);
248 unsigned long enable;
249 enum netxbig_led_mode mode;
250 int mode_val;
251 int ret;
252
253 ret = kstrtoul(buff, 10, &enable);
254 if (ret < 0)
255 return ret;
256
257 enable = !!enable;
258
259 spin_lock_irq(&led_dat->lock);
260
261 if (led_dat->sata == enable) {
262 ret = count;
263 goto exit_unlock;
264 }
265
266 if (led_dat->mode != NETXBIG_LED_ON &&
267 led_dat->mode != NETXBIG_LED_SATA)
268 mode = led_dat->mode; /* Keep modes 'off' and 'timer'. */
269 else if (enable)
270 mode = NETXBIG_LED_SATA;
271 else
272 mode = NETXBIG_LED_ON;
273
274 mode_val = led_dat->mode_val[mode];
275 if (mode_val == NETXBIG_LED_INVALID_MODE) {
276 ret = -EINVAL;
277 goto exit_unlock;
278 }
279
280 gpio_ext_set_value(led_dat->gpio_ext, led_dat->mode_addr, mode_val);
281 led_dat->mode = mode;
282 led_dat->sata = enable;
283
284 ret = count;
285
286 exit_unlock:
287 spin_unlock_irq(&led_dat->lock);
288
289 return ret;
290 }
291
netxbig_led_sata_show(struct device * dev,struct device_attribute * attr,char * buf)292 static ssize_t netxbig_led_sata_show(struct device *dev,
293 struct device_attribute *attr, char *buf)
294 {
295 struct led_classdev *led_cdev = dev_get_drvdata(dev);
296 struct netxbig_led_data *led_dat =
297 container_of(led_cdev, struct netxbig_led_data, cdev);
298
299 return sprintf(buf, "%d\n", led_dat->sata);
300 }
301
302 static DEVICE_ATTR(sata, 0644, netxbig_led_sata_show, netxbig_led_sata_store);
303
304 static struct attribute *netxbig_led_attrs[] = {
305 &dev_attr_sata.attr,
306 NULL
307 };
308 ATTRIBUTE_GROUPS(netxbig_led);
309
create_netxbig_led(struct platform_device * pdev,struct netxbig_led_platform_data * pdata,struct netxbig_led_data * led_dat,const struct netxbig_led * template)310 static int create_netxbig_led(struct platform_device *pdev,
311 struct netxbig_led_platform_data *pdata,
312 struct netxbig_led_data *led_dat,
313 const struct netxbig_led *template)
314 {
315 spin_lock_init(&led_dat->lock);
316 led_dat->gpio_ext = pdata->gpio_ext;
317 led_dat->cdev.name = template->name;
318 led_dat->cdev.default_trigger = template->default_trigger;
319 led_dat->cdev.blink_set = netxbig_led_blink_set;
320 led_dat->cdev.brightness_set = netxbig_led_set;
321 /*
322 * Because the GPIO extension bus don't allow to read registers
323 * value, there is no way to probe the LED initial state.
324 * So, the initial sysfs LED value for the "brightness" and "sata"
325 * attributes are inconsistent.
326 *
327 * Note that the initial LED state can't be reconfigured.
328 * The reason is that the LED behaviour must stay uniform during
329 * the whole boot process (bootloader+linux).
330 */
331 led_dat->sata = 0;
332 led_dat->cdev.brightness = LED_OFF;
333 led_dat->cdev.max_brightness = template->bright_max;
334 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
335 led_dat->mode_addr = template->mode_addr;
336 led_dat->mode_val = template->mode_val;
337 led_dat->bright_addr = template->bright_addr;
338 led_dat->timer = pdata->timer;
339 led_dat->num_timer = pdata->num_timer;
340 /*
341 * If available, expose the SATA activity blink capability through
342 * a "sata" sysfs attribute.
343 */
344 if (led_dat->mode_val[NETXBIG_LED_SATA] != NETXBIG_LED_INVALID_MODE)
345 led_dat->cdev.groups = netxbig_led_groups;
346
347 return devm_led_classdev_register(&pdev->dev, &led_dat->cdev);
348 }
349
gpio_ext_get_of_pdata(struct device * dev,struct device_node * np,struct netxbig_gpio_ext * gpio_ext)350 static int gpio_ext_get_of_pdata(struct device *dev, struct device_node *np,
351 struct netxbig_gpio_ext *gpio_ext)
352 {
353 int *addr, *data;
354 int num_addr, num_data;
355 int ret;
356 int i;
357
358 ret = of_gpio_named_count(np, "addr-gpios");
359 if (ret < 0) {
360 dev_err(dev,
361 "Failed to count GPIOs in DT property addr-gpios\n");
362 return ret;
363 }
364 num_addr = ret;
365 addr = devm_kcalloc(dev, num_addr, sizeof(*addr), GFP_KERNEL);
366 if (!addr)
367 return -ENOMEM;
368
369 for (i = 0; i < num_addr; i++) {
370 ret = of_get_named_gpio(np, "addr-gpios", i);
371 if (ret < 0)
372 return ret;
373 addr[i] = ret;
374 }
375 gpio_ext->addr = addr;
376 gpio_ext->num_addr = num_addr;
377
378 ret = of_gpio_named_count(np, "data-gpios");
379 if (ret < 0) {
380 dev_err(dev,
381 "Failed to count GPIOs in DT property data-gpios\n");
382 return ret;
383 }
384 num_data = ret;
385 data = devm_kcalloc(dev, num_data, sizeof(*data), GFP_KERNEL);
386 if (!data)
387 return -ENOMEM;
388
389 for (i = 0; i < num_data; i++) {
390 ret = of_get_named_gpio(np, "data-gpios", i);
391 if (ret < 0)
392 return ret;
393 data[i] = ret;
394 }
395 gpio_ext->data = data;
396 gpio_ext->num_data = num_data;
397
398 ret = of_get_named_gpio(np, "enable-gpio", 0);
399 if (ret < 0) {
400 dev_err(dev,
401 "Failed to get GPIO from DT property enable-gpio\n");
402 return ret;
403 }
404 gpio_ext->enable = ret;
405
406 return 0;
407 }
408
netxbig_leds_get_of_pdata(struct device * dev,struct netxbig_led_platform_data * pdata)409 static int netxbig_leds_get_of_pdata(struct device *dev,
410 struct netxbig_led_platform_data *pdata)
411 {
412 struct device_node *np = dev->of_node;
413 struct device_node *gpio_ext_np;
414 struct device_node *child;
415 struct netxbig_gpio_ext *gpio_ext;
416 struct netxbig_led_timer *timers;
417 struct netxbig_led *leds, *led;
418 int num_timers;
419 int num_leds = 0;
420 int ret;
421 int i;
422
423 /* GPIO extension */
424 gpio_ext_np = of_parse_phandle(np, "gpio-ext", 0);
425 if (!gpio_ext_np) {
426 dev_err(dev, "Failed to get DT handle gpio-ext\n");
427 return -EINVAL;
428 }
429
430 gpio_ext = devm_kzalloc(dev, sizeof(*gpio_ext), GFP_KERNEL);
431 if (!gpio_ext) {
432 of_node_put(gpio_ext_np);
433 return -ENOMEM;
434 }
435 ret = gpio_ext_get_of_pdata(dev, gpio_ext_np, gpio_ext);
436 of_node_put(gpio_ext_np);
437 if (ret)
438 return ret;
439 pdata->gpio_ext = gpio_ext;
440
441 /* Timers (optional) */
442 ret = of_property_count_u32_elems(np, "timers");
443 if (ret > 0) {
444 if (ret % 3)
445 return -EINVAL;
446 num_timers = ret / 3;
447 timers = devm_kcalloc(dev, num_timers, sizeof(*timers),
448 GFP_KERNEL);
449 if (!timers)
450 return -ENOMEM;
451 for (i = 0; i < num_timers; i++) {
452 u32 tmp;
453
454 of_property_read_u32_index(np, "timers", 3 * i,
455 &timers[i].mode);
456 if (timers[i].mode >= NETXBIG_LED_MODE_NUM)
457 return -EINVAL;
458 of_property_read_u32_index(np, "timers",
459 3 * i + 1, &tmp);
460 timers[i].delay_on = tmp;
461 of_property_read_u32_index(np, "timers",
462 3 * i + 2, &tmp);
463 timers[i].delay_off = tmp;
464 }
465 pdata->timer = timers;
466 pdata->num_timer = num_timers;
467 }
468
469 /* LEDs */
470 num_leds = of_get_child_count(np);
471 if (!num_leds) {
472 dev_err(dev, "No LED subnodes found in DT\n");
473 return -ENODEV;
474 }
475
476 leds = devm_kcalloc(dev, num_leds, sizeof(*leds), GFP_KERNEL);
477 if (!leds)
478 return -ENOMEM;
479
480 led = leds;
481 for_each_child_of_node(np, child) {
482 const char *string;
483 int *mode_val;
484 int num_modes;
485
486 ret = of_property_read_u32(child, "mode-addr",
487 &led->mode_addr);
488 if (ret)
489 goto err_node_put;
490
491 ret = of_property_read_u32(child, "bright-addr",
492 &led->bright_addr);
493 if (ret)
494 goto err_node_put;
495
496 ret = of_property_read_u32(child, "max-brightness",
497 &led->bright_max);
498 if (ret)
499 goto err_node_put;
500
501 mode_val =
502 devm_kcalloc(dev,
503 NETXBIG_LED_MODE_NUM, sizeof(*mode_val),
504 GFP_KERNEL);
505 if (!mode_val) {
506 ret = -ENOMEM;
507 goto err_node_put;
508 }
509
510 for (i = 0; i < NETXBIG_LED_MODE_NUM; i++)
511 mode_val[i] = NETXBIG_LED_INVALID_MODE;
512
513 ret = of_property_count_u32_elems(child, "mode-val");
514 if (ret < 0 || ret % 2) {
515 ret = -EINVAL;
516 goto err_node_put;
517 }
518 num_modes = ret / 2;
519 if (num_modes > NETXBIG_LED_MODE_NUM) {
520 ret = -EINVAL;
521 goto err_node_put;
522 }
523
524 for (i = 0; i < num_modes; i++) {
525 int mode;
526 int val;
527
528 of_property_read_u32_index(child,
529 "mode-val", 2 * i, &mode);
530 of_property_read_u32_index(child,
531 "mode-val", 2 * i + 1, &val);
532 if (mode >= NETXBIG_LED_MODE_NUM) {
533 ret = -EINVAL;
534 goto err_node_put;
535 }
536 mode_val[mode] = val;
537 }
538 led->mode_val = mode_val;
539
540 if (!of_property_read_string(child, "label", &string))
541 led->name = string;
542 else
543 led->name = child->name;
544
545 if (!of_property_read_string(child,
546 "linux,default-trigger", &string))
547 led->default_trigger = string;
548
549 led++;
550 }
551
552 pdata->leds = leds;
553 pdata->num_leds = num_leds;
554
555 return 0;
556
557 err_node_put:
558 of_node_put(child);
559 return ret;
560 }
561
562 static const struct of_device_id of_netxbig_leds_match[] = {
563 { .compatible = "lacie,netxbig-leds", },
564 {},
565 };
566 MODULE_DEVICE_TABLE(of, of_netxbig_leds_match);
567
netxbig_led_probe(struct platform_device * pdev)568 static int netxbig_led_probe(struct platform_device *pdev)
569 {
570 struct netxbig_led_platform_data *pdata;
571 struct netxbig_led_data *leds_data;
572 int i;
573 int ret;
574
575 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
576 if (!pdata)
577 return -ENOMEM;
578 ret = netxbig_leds_get_of_pdata(&pdev->dev, pdata);
579 if (ret)
580 return ret;
581
582 leds_data = devm_kcalloc(&pdev->dev,
583 pdata->num_leds, sizeof(*leds_data),
584 GFP_KERNEL);
585 if (!leds_data)
586 return -ENOMEM;
587
588 ret = gpio_ext_init(pdev, pdata->gpio_ext);
589 if (ret < 0)
590 return ret;
591
592 for (i = 0; i < pdata->num_leds; i++) {
593 ret = create_netxbig_led(pdev, pdata,
594 &leds_data[i], &pdata->leds[i]);
595 if (ret < 0)
596 return ret;
597 }
598
599 return 0;
600 }
601
602 static struct platform_driver netxbig_led_driver = {
603 .probe = netxbig_led_probe,
604 .driver = {
605 .name = "leds-netxbig",
606 .of_match_table = of_netxbig_leds_match,
607 },
608 };
609
610 module_platform_driver(netxbig_led_driver);
611
612 MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>");
613 MODULE_DESCRIPTION("LED driver for LaCie xBig Network boards");
614 MODULE_LICENSE("GPL");
615 MODULE_ALIAS("platform:leds-netxbig");
616