xref: /openbmc/linux/drivers/leds/leds-blinkm.c (revision a8da474e)
1 /*
2  *  leds-blinkm.c
3  *  (c) Jan-Simon Möller (dl9pf@gmx.de)
4  *
5  *  This program is free software; you can redistribute it and/or modify
6  *  it under the terms of the GNU General Public License as published by
7  *  the Free Software Foundation; either version 2 of the License, or
8  *  (at your option) any later version.
9  *
10  *  This program is distributed in the hope that it will be useful,
11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *  GNU General Public License for more details.
14  *
15  *  You should have received a copy of the GNU General Public License
16  *  along with this program; if not, write to the Free Software
17  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18  */
19 
20 #include <linux/module.h>
21 #include <linux/slab.h>
22 #include <linux/jiffies.h>
23 #include <linux/i2c.h>
24 #include <linux/err.h>
25 #include <linux/mutex.h>
26 #include <linux/sysfs.h>
27 #include <linux/printk.h>
28 #include <linux/pm_runtime.h>
29 #include <linux/leds.h>
30 #include <linux/delay.h>
31 
32 /* Addresses to scan - BlinkM is on 0x09 by default*/
33 static const unsigned short normal_i2c[] = { 0x09, I2C_CLIENT_END };
34 
35 static int blinkm_transfer_hw(struct i2c_client *client, int cmd);
36 static int blinkm_test_run(struct i2c_client *client);
37 
38 struct blinkm_led {
39 	struct i2c_client *i2c_client;
40 	struct led_classdev led_cdev;
41 	int id;
42 	atomic_t active;
43 };
44 
45 struct blinkm_work {
46 	struct blinkm_led *blinkm_led;
47 	struct work_struct work;
48 };
49 
50 #define cdev_to_blmled(c)          container_of(c, struct blinkm_led, led_cdev)
51 #define work_to_blmwork(c)         container_of(c, struct blinkm_work, work)
52 
53 struct blinkm_data {
54 	struct i2c_client *i2c_client;
55 	struct mutex update_lock;
56 	/* used for led class interface */
57 	struct blinkm_led blinkm_leds[3];
58 	/* used for "blinkm" sysfs interface */
59 	u8 red;			/* color red */
60 	u8 green;		/* color green */
61 	u8 blue;		/* color blue */
62 	/* next values to use for transfer */
63 	u8 next_red;			/* color red */
64 	u8 next_green;		/* color green */
65 	u8 next_blue;		/* color blue */
66 	/* internal use */
67 	u8 args[7];		/* set of args for transmission */
68 	u8 i2c_addr;		/* i2c addr */
69 	u8 fw_ver;		/* firmware version */
70 	/* used, but not from userspace */
71 	u8 hue;			/* HSB  hue */
72 	u8 saturation;		/* HSB  saturation */
73 	u8 brightness;		/* HSB  brightness */
74 	u8 next_hue;			/* HSB  hue */
75 	u8 next_saturation;		/* HSB  saturation */
76 	u8 next_brightness;		/* HSB  brightness */
77 	/* currently unused / todo */
78 	u8 fade_speed;		/* fade speed     1 - 255 */
79 	s8 time_adjust;		/* time adjust -128 - 127 */
80 	u8 fade:1;		/* fade on = 1, off = 0 */
81 	u8 rand:1;		/* rand fade mode on = 1 */
82 	u8 script_id;		/* script ID */
83 	u8 script_repeats;	/* repeats of script */
84 	u8 script_startline;	/* line to start */
85 };
86 
87 /* Colors */
88 #define RED   0
89 #define GREEN 1
90 #define BLUE  2
91 
92 /* mapping command names to cmd chars - see datasheet */
93 #define BLM_GO_RGB            0
94 #define BLM_FADE_RGB          1
95 #define BLM_FADE_HSB          2
96 #define BLM_FADE_RAND_RGB     3
97 #define BLM_FADE_RAND_HSB     4
98 #define BLM_PLAY_SCRIPT       5
99 #define BLM_STOP_SCRIPT       6
100 #define BLM_SET_FADE_SPEED    7
101 #define BLM_SET_TIME_ADJ      8
102 #define BLM_GET_CUR_RGB       9
103 #define BLM_WRITE_SCRIPT_LINE 10
104 #define BLM_READ_SCRIPT_LINE  11
105 #define BLM_SET_SCRIPT_LR     12	/* Length & Repeats */
106 #define BLM_SET_ADDR          13
107 #define BLM_GET_ADDR          14
108 #define BLM_GET_FW_VER        15
109 #define BLM_SET_STARTUP_PARAM 16
110 
111 /* BlinkM Commands
112  *  as extracted out of the datasheet:
113  *
114  *  cmdchar = command (ascii)
115  *  cmdbyte = command in hex
116  *  nr_args = number of arguments (to send)
117  *  nr_ret  = number of return values (to read)
118  *  dir = direction (0 = read, 1 = write, 2 = both)
119  *
120  */
121 static const struct {
122 	char cmdchar;
123 	u8 cmdbyte;
124 	u8 nr_args;
125 	u8 nr_ret;
126 	u8 dir:2;
127 } blinkm_cmds[17] = {
128   /* cmdchar, cmdbyte, nr_args, nr_ret,  dir */
129 	{ 'n', 0x6e, 3, 0, 1},
130 	{ 'c', 0x63, 3, 0, 1},
131 	{ 'h', 0x68, 3, 0, 1},
132 	{ 'C', 0x43, 3, 0, 1},
133 	{ 'H', 0x48, 3, 0, 1},
134 	{ 'p', 0x70, 3, 0, 1},
135 	{ 'o', 0x6f, 0, 0, 1},
136 	{ 'f', 0x66, 1, 0, 1},
137 	{ 't', 0x74, 1, 0, 1},
138 	{ 'g', 0x67, 0, 3, 0},
139 	{ 'W', 0x57, 7, 0, 1},
140 	{ 'R', 0x52, 2, 5, 2},
141 	{ 'L', 0x4c, 3, 0, 1},
142 	{ 'A', 0x41, 4, 0, 1},
143 	{ 'a', 0x61, 0, 1, 0},
144 	{ 'Z', 0x5a, 0, 1, 0},
145 	{ 'B', 0x42, 5, 0, 1},
146 };
147 
148 static ssize_t show_color_common(struct device *dev, char *buf, int color)
149 {
150 	struct i2c_client *client;
151 	struct blinkm_data *data;
152 	int ret;
153 
154 	client = to_i2c_client(dev);
155 	data = i2c_get_clientdata(client);
156 
157 	ret = blinkm_transfer_hw(client, BLM_GET_CUR_RGB);
158 	if (ret < 0)
159 		return ret;
160 	switch (color) {
161 	case RED:
162 		return scnprintf(buf, PAGE_SIZE, "%02X\n", data->red);
163 	case GREEN:
164 		return scnprintf(buf, PAGE_SIZE, "%02X\n", data->green);
165 	case BLUE:
166 		return scnprintf(buf, PAGE_SIZE, "%02X\n", data->blue);
167 	default:
168 		return -EINVAL;
169 	}
170 	return -EINVAL;
171 }
172 
173 static int store_color_common(struct device *dev, const char *buf, int color)
174 {
175 	struct i2c_client *client;
176 	struct blinkm_data *data;
177 	int ret;
178 	u8 value;
179 
180 	client = to_i2c_client(dev);
181 	data = i2c_get_clientdata(client);
182 
183 	ret = kstrtou8(buf, 10, &value);
184 	if (ret < 0) {
185 		dev_err(dev, "BlinkM: value too large!\n");
186 		return ret;
187 	}
188 
189 	switch (color) {
190 	case RED:
191 		data->next_red = value;
192 		break;
193 	case GREEN:
194 		data->next_green = value;
195 		break;
196 	case BLUE:
197 		data->next_blue = value;
198 		break;
199 	default:
200 		return -EINVAL;
201 	}
202 
203 	dev_dbg(dev, "next_red = %d, next_green = %d, next_blue = %d\n",
204 			data->next_red, data->next_green, data->next_blue);
205 
206 	/* if mode ... */
207 	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
208 	if (ret < 0) {
209 		dev_err(dev, "BlinkM: can't set RGB\n");
210 		return ret;
211 	}
212 	return 0;
213 }
214 
215 static ssize_t show_red(struct device *dev, struct device_attribute *attr,
216 			char *buf)
217 {
218 	return show_color_common(dev, buf, RED);
219 }
220 
221 static ssize_t store_red(struct device *dev, struct device_attribute *attr,
222 			 const char *buf, size_t count)
223 {
224 	int ret;
225 
226 	ret = store_color_common(dev, buf, RED);
227 	if (ret < 0)
228 		return ret;
229 	return count;
230 }
231 
232 static DEVICE_ATTR(red, S_IRUGO | S_IWUSR, show_red, store_red);
233 
234 static ssize_t show_green(struct device *dev, struct device_attribute *attr,
235 			  char *buf)
236 {
237 	return show_color_common(dev, buf, GREEN);
238 }
239 
240 static ssize_t store_green(struct device *dev, struct device_attribute *attr,
241 			   const char *buf, size_t count)
242 {
243 
244 	int ret;
245 
246 	ret = store_color_common(dev, buf, GREEN);
247 	if (ret < 0)
248 		return ret;
249 	return count;
250 }
251 
252 static DEVICE_ATTR(green, S_IRUGO | S_IWUSR, show_green, store_green);
253 
254 static ssize_t show_blue(struct device *dev, struct device_attribute *attr,
255 			 char *buf)
256 {
257 	return show_color_common(dev, buf, BLUE);
258 }
259 
260 static ssize_t store_blue(struct device *dev, struct device_attribute *attr,
261 			  const char *buf, size_t count)
262 {
263 	int ret;
264 
265 	ret = store_color_common(dev, buf, BLUE);
266 	if (ret < 0)
267 		return ret;
268 	return count;
269 }
270 
271 static DEVICE_ATTR(blue, S_IRUGO | S_IWUSR, show_blue, store_blue);
272 
273 static ssize_t show_test(struct device *dev, struct device_attribute *attr,
274 			 char *buf)
275 {
276 	return scnprintf(buf, PAGE_SIZE,
277 			 "#Write into test to start test sequence!#\n");
278 }
279 
280 static ssize_t store_test(struct device *dev, struct device_attribute *attr,
281 			  const char *buf, size_t count)
282 {
283 
284 	struct i2c_client *client;
285 	int ret;
286 	client = to_i2c_client(dev);
287 
288 	/*test */
289 	ret = blinkm_test_run(client);
290 	if (ret < 0)
291 		return ret;
292 
293 	return count;
294 }
295 
296 static DEVICE_ATTR(test, S_IRUGO | S_IWUSR, show_test, store_test);
297 
298 /* TODO: HSB, fade, timeadj, script ... */
299 
300 static struct attribute *blinkm_attrs[] = {
301 	&dev_attr_red.attr,
302 	&dev_attr_green.attr,
303 	&dev_attr_blue.attr,
304 	&dev_attr_test.attr,
305 	NULL,
306 };
307 
308 static struct attribute_group blinkm_group = {
309 	.name = "blinkm",
310 	.attrs = blinkm_attrs,
311 };
312 
313 static int blinkm_write(struct i2c_client *client, int cmd, u8 *arg)
314 {
315 	int result;
316 	int i;
317 	int arglen = blinkm_cmds[cmd].nr_args;
318 	/* write out cmd to blinkm - always / default step */
319 	result = i2c_smbus_write_byte(client, blinkm_cmds[cmd].cmdbyte);
320 	if (result < 0)
321 		return result;
322 	/* no args to write out */
323 	if (arglen == 0)
324 		return 0;
325 
326 	for (i = 0; i < arglen; i++) {
327 		/* repeat for arglen */
328 		result = i2c_smbus_write_byte(client, arg[i]);
329 		if (result < 0)
330 			return result;
331 	}
332 	return 0;
333 }
334 
335 static int blinkm_read(struct i2c_client *client, int cmd, u8 *arg)
336 {
337 	int result;
338 	int i;
339 	int retlen = blinkm_cmds[cmd].nr_ret;
340 	for (i = 0; i < retlen; i++) {
341 		/* repeat for retlen */
342 		result = i2c_smbus_read_byte(client);
343 		if (result < 0)
344 			return result;
345 		arg[i] = result;
346 	}
347 
348 	return 0;
349 }
350 
351 static int blinkm_transfer_hw(struct i2c_client *client, int cmd)
352 {
353 	/* the protocol is simple but non-standard:
354 	 * e.g.  cmd 'g' (= 0x67) for "get device address"
355 	 * - which defaults to 0x09 - would be the sequence:
356 	 *   a) write 0x67 to the device (byte write)
357 	 *   b) read the value (0x09) back right after (byte read)
358 	 *
359 	 * Watch out for "unfinished" sequences (i.e. not enough reads
360 	 * or writes after a command. It will make the blinkM misbehave.
361 	 * Sequence is key here.
362 	 */
363 
364 	/* args / return are in private data struct */
365 	struct blinkm_data *data = i2c_get_clientdata(client);
366 
367 	/* We start hardware transfers which are not to be
368 	 * mixed with other commands. Aquire a lock now. */
369 	if (mutex_lock_interruptible(&data->update_lock) < 0)
370 		return -EAGAIN;
371 
372 	/* switch cmd - usually write before reads */
373 	switch (cmd) {
374 	case BLM_FADE_RAND_RGB:
375 	case BLM_GO_RGB:
376 	case BLM_FADE_RGB:
377 		data->args[0] = data->next_red;
378 		data->args[1] = data->next_green;
379 		data->args[2] = data->next_blue;
380 		blinkm_write(client, cmd, data->args);
381 		data->red = data->args[0];
382 		data->green = data->args[1];
383 		data->blue = data->args[2];
384 		break;
385 	case BLM_FADE_HSB:
386 	case BLM_FADE_RAND_HSB:
387 		data->args[0] = data->next_hue;
388 		data->args[1] = data->next_saturation;
389 		data->args[2] = data->next_brightness;
390 		blinkm_write(client, cmd, data->args);
391 		data->hue = data->next_hue;
392 		data->saturation = data->next_saturation;
393 		data->brightness = data->next_brightness;
394 		break;
395 	case BLM_PLAY_SCRIPT:
396 		data->args[0] = data->script_id;
397 		data->args[1] = data->script_repeats;
398 		data->args[2] = data->script_startline;
399 		blinkm_write(client, cmd, data->args);
400 		break;
401 	case BLM_STOP_SCRIPT:
402 		blinkm_write(client, cmd, NULL);
403 		break;
404 	case BLM_GET_CUR_RGB:
405 		data->args[0] = data->red;
406 		data->args[1] = data->green;
407 		data->args[2] = data->blue;
408 		blinkm_write(client, cmd, NULL);
409 		blinkm_read(client, cmd, data->args);
410 		data->red = data->args[0];
411 		data->green = data->args[1];
412 		data->blue = data->args[2];
413 		break;
414 	case BLM_GET_ADDR:
415 		data->args[0] = data->i2c_addr;
416 		blinkm_write(client, cmd, NULL);
417 		blinkm_read(client, cmd, data->args);
418 		data->i2c_addr = data->args[0];
419 		break;
420 	case BLM_SET_TIME_ADJ:
421 	case BLM_SET_FADE_SPEED:
422 	case BLM_READ_SCRIPT_LINE:
423 	case BLM_WRITE_SCRIPT_LINE:
424 	case BLM_SET_SCRIPT_LR:
425 	case BLM_SET_ADDR:
426 	case BLM_GET_FW_VER:
427 	case BLM_SET_STARTUP_PARAM:
428 		dev_err(&client->dev,
429 				"BlinkM: cmd %d not implemented yet.\n", cmd);
430 		break;
431 	default:
432 		dev_err(&client->dev, "BlinkM: unknown command %d\n", cmd);
433 		mutex_unlock(&data->update_lock);
434 		return -EINVAL;
435 	}			/* end switch(cmd) */
436 
437 	/* transfers done, unlock */
438 	mutex_unlock(&data->update_lock);
439 	return 0;
440 }
441 
442 static void led_work(struct work_struct *work)
443 {
444 	int ret;
445 	struct blinkm_led *led;
446 	struct blinkm_data *data;
447 	struct blinkm_work *blm_work = work_to_blmwork(work);
448 
449 	led = blm_work->blinkm_led;
450 	data = i2c_get_clientdata(led->i2c_client);
451 	ret = blinkm_transfer_hw(led->i2c_client, BLM_GO_RGB);
452 	atomic_dec(&led->active);
453 	dev_dbg(&led->i2c_client->dev,
454 			"# DONE # next_red = %d, next_green = %d,"
455 			" next_blue = %d, active = %d\n",
456 			data->next_red, data->next_green,
457 			data->next_blue, atomic_read(&led->active));
458 	kfree(blm_work);
459 }
460 
461 static int blinkm_led_common_set(struct led_classdev *led_cdev,
462 				 enum led_brightness value, int color)
463 {
464 	/* led_brightness is 0, 127 or 255 - we just use it here as-is */
465 	struct blinkm_led *led = cdev_to_blmled(led_cdev);
466 	struct blinkm_data *data = i2c_get_clientdata(led->i2c_client);
467 	struct blinkm_work *bl_work;
468 
469 	switch (color) {
470 	case RED:
471 		/* bail out if there's no change */
472 		if (data->next_red == (u8) value)
473 			return 0;
474 		/* we assume a quite fast sequence here ([off]->on->off)
475 		 * think of network led trigger - we cannot blink that fast, so
476 		 * in case we already have a off->on->off transition queued up,
477 		 * we refuse to queue up more.
478 		 * Revisit: fast-changing brightness. */
479 		if (atomic_read(&led->active) > 1)
480 			return 0;
481 		data->next_red = (u8) value;
482 		break;
483 	case GREEN:
484 		/* bail out if there's no change */
485 		if (data->next_green == (u8) value)
486 			return 0;
487 		/* we assume a quite fast sequence here ([off]->on->off)
488 		 * Revisit: fast-changing brightness. */
489 		if (atomic_read(&led->active) > 1)
490 			return 0;
491 		data->next_green = (u8) value;
492 		break;
493 	case BLUE:
494 		/* bail out if there's no change */
495 		if (data->next_blue == (u8) value)
496 			return 0;
497 		/* we assume a quite fast sequence here ([off]->on->off)
498 		 * Revisit: fast-changing brightness. */
499 		if (atomic_read(&led->active) > 1)
500 			return 0;
501 		data->next_blue = (u8) value;
502 		break;
503 
504 	default:
505 		dev_err(&led->i2c_client->dev, "BlinkM: unknown color.\n");
506 		return -EINVAL;
507 	}
508 
509 	bl_work = kzalloc(sizeof(*bl_work), GFP_ATOMIC);
510 	if (!bl_work)
511 		return -ENOMEM;
512 
513 	atomic_inc(&led->active);
514 	dev_dbg(&led->i2c_client->dev,
515 			"#TO_SCHED# next_red = %d, next_green = %d,"
516 			" next_blue = %d, active = %d\n",
517 			data->next_red, data->next_green,
518 			data->next_blue, atomic_read(&led->active));
519 
520 	/* a fresh work _item_ for each change */
521 	bl_work->blinkm_led = led;
522 	INIT_WORK(&bl_work->work, led_work);
523 	/* queue work in own queue for easy sync on exit*/
524 	schedule_work(&bl_work->work);
525 
526 	return 0;
527 }
528 
529 static void blinkm_led_red_set(struct led_classdev *led_cdev,
530 			       enum led_brightness value)
531 {
532 	blinkm_led_common_set(led_cdev, value, RED);
533 }
534 
535 static void blinkm_led_green_set(struct led_classdev *led_cdev,
536 				 enum led_brightness value)
537 {
538 	blinkm_led_common_set(led_cdev, value, GREEN);
539 }
540 
541 static void blinkm_led_blue_set(struct led_classdev *led_cdev,
542 				enum led_brightness value)
543 {
544 	blinkm_led_common_set(led_cdev, value, BLUE);
545 }
546 
547 static void blinkm_init_hw(struct i2c_client *client)
548 {
549 	int ret;
550 	ret = blinkm_transfer_hw(client, BLM_STOP_SCRIPT);
551 	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
552 }
553 
554 static int blinkm_test_run(struct i2c_client *client)
555 {
556 	int ret;
557 	struct blinkm_data *data = i2c_get_clientdata(client);
558 
559 	data->next_red = 0x01;
560 	data->next_green = 0x05;
561 	data->next_blue = 0x10;
562 	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
563 	if (ret < 0)
564 		return ret;
565 	msleep(2000);
566 
567 	data->next_red = 0x25;
568 	data->next_green = 0x10;
569 	data->next_blue = 0x31;
570 	ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
571 	if (ret < 0)
572 		return ret;
573 	msleep(2000);
574 
575 	data->next_hue = 0x50;
576 	data->next_saturation = 0x10;
577 	data->next_brightness = 0x20;
578 	ret = blinkm_transfer_hw(client, BLM_FADE_HSB);
579 	if (ret < 0)
580 		return ret;
581 	msleep(2000);
582 
583 	return 0;
584 }
585 
586 /* Return 0 if detection is successful, -ENODEV otherwise */
587 static int blinkm_detect(struct i2c_client *client, struct i2c_board_info *info)
588 {
589 	struct i2c_adapter *adapter = client->adapter;
590 	int ret;
591 	int count = 99;
592 	u8 tmpargs[7];
593 
594 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
595 				     | I2C_FUNC_SMBUS_WORD_DATA
596 				     | I2C_FUNC_SMBUS_WRITE_BYTE))
597 		return -ENODEV;
598 
599 	/* Now, we do the remaining detection. Simple for now. */
600 	/* We might need more guards to protect other i2c slaves */
601 
602 	/* make sure the blinkM is balanced (read/writes) */
603 	while (count > 0) {
604 		ret = blinkm_write(client, BLM_GET_ADDR, NULL);
605 		usleep_range(5000, 10000);
606 		ret = blinkm_read(client, BLM_GET_ADDR, tmpargs);
607 		usleep_range(5000, 10000);
608 		if (tmpargs[0] == 0x09)
609 			count = 0;
610 		count--;
611 	}
612 
613 	/* Step 1: Read BlinkM address back  -  cmd_char 'a' */
614 	ret = blinkm_write(client, BLM_GET_ADDR, NULL);
615 	if (ret < 0)
616 		return ret;
617 	usleep_range(20000, 30000);	/* allow a small delay */
618 	ret = blinkm_read(client, BLM_GET_ADDR, tmpargs);
619 	if (ret < 0)
620 		return ret;
621 
622 	if (tmpargs[0] != 0x09) {
623 		dev_err(&client->dev, "enodev DEV ADDR = 0x%02X\n", tmpargs[0]);
624 		return -ENODEV;
625 	}
626 
627 	strlcpy(info->type, "blinkm", I2C_NAME_SIZE);
628 	return 0;
629 }
630 
631 static int blinkm_probe(struct i2c_client *client,
632 			const struct i2c_device_id *id)
633 {
634 	struct blinkm_data *data;
635 	struct blinkm_led *led[3];
636 	int err, i;
637 	char blinkm_led_name[28];
638 
639 	data = devm_kzalloc(&client->dev,
640 			sizeof(struct blinkm_data), GFP_KERNEL);
641 	if (!data) {
642 		err = -ENOMEM;
643 		goto exit;
644 	}
645 
646 	data->i2c_addr = 0x09;
647 	data->i2c_addr = 0x08;
648 	/* i2c addr  - use fake addr of 0x08 initially (real is 0x09) */
649 	data->fw_ver = 0xfe;
650 	/* firmware version - use fake until we read real value
651 	 * (currently broken - BlinkM confused!) */
652 	data->script_id = 0x01;
653 	data->i2c_client = client;
654 
655 	i2c_set_clientdata(client, data);
656 	mutex_init(&data->update_lock);
657 
658 	/* Register sysfs hooks */
659 	err = sysfs_create_group(&client->dev.kobj, &blinkm_group);
660 	if (err < 0) {
661 		dev_err(&client->dev, "couldn't register sysfs group\n");
662 		goto exit;
663 	}
664 
665 	for (i = 0; i < 3; i++) {
666 		/* RED = 0, GREEN = 1, BLUE = 2 */
667 		led[i] = &data->blinkm_leds[i];
668 		led[i]->i2c_client = client;
669 		led[i]->id = i;
670 		led[i]->led_cdev.max_brightness = 255;
671 		led[i]->led_cdev.flags = LED_CORE_SUSPENDRESUME;
672 		atomic_set(&led[i]->active, 0);
673 		switch (i) {
674 		case RED:
675 			snprintf(blinkm_led_name, sizeof(blinkm_led_name),
676 					 "blinkm-%d-%d-red",
677 					 client->adapter->nr,
678 					 client->addr);
679 			led[i]->led_cdev.name = blinkm_led_name;
680 			led[i]->led_cdev.brightness_set = blinkm_led_red_set;
681 			err = led_classdev_register(&client->dev,
682 						    &led[i]->led_cdev);
683 			if (err < 0) {
684 				dev_err(&client->dev,
685 					"couldn't register LED %s\n",
686 					led[i]->led_cdev.name);
687 				goto failred;
688 			}
689 			break;
690 		case GREEN:
691 			snprintf(blinkm_led_name, sizeof(blinkm_led_name),
692 					 "blinkm-%d-%d-green",
693 					 client->adapter->nr,
694 					 client->addr);
695 			led[i]->led_cdev.name = blinkm_led_name;
696 			led[i]->led_cdev.brightness_set = blinkm_led_green_set;
697 			err = led_classdev_register(&client->dev,
698 						    &led[i]->led_cdev);
699 			if (err < 0) {
700 				dev_err(&client->dev,
701 					"couldn't register LED %s\n",
702 					led[i]->led_cdev.name);
703 				goto failgreen;
704 			}
705 			break;
706 		case BLUE:
707 			snprintf(blinkm_led_name, sizeof(blinkm_led_name),
708 					 "blinkm-%d-%d-blue",
709 					 client->adapter->nr,
710 					 client->addr);
711 			led[i]->led_cdev.name = blinkm_led_name;
712 			led[i]->led_cdev.brightness_set = blinkm_led_blue_set;
713 			err = led_classdev_register(&client->dev,
714 						    &led[i]->led_cdev);
715 			if (err < 0) {
716 				dev_err(&client->dev,
717 					"couldn't register LED %s\n",
718 					led[i]->led_cdev.name);
719 				goto failblue;
720 			}
721 			break;
722 		}		/* end switch */
723 	}			/* end for */
724 
725 	/* Initialize the blinkm */
726 	blinkm_init_hw(client);
727 
728 	return 0;
729 
730 failblue:
731 	led_classdev_unregister(&led[GREEN]->led_cdev);
732 
733 failgreen:
734 	led_classdev_unregister(&led[RED]->led_cdev);
735 
736 failred:
737 	sysfs_remove_group(&client->dev.kobj, &blinkm_group);
738 exit:
739 	return err;
740 }
741 
742 static int blinkm_remove(struct i2c_client *client)
743 {
744 	struct blinkm_data *data = i2c_get_clientdata(client);
745 	int ret = 0;
746 	int i;
747 
748 	/* make sure no workqueue entries are pending */
749 	for (i = 0; i < 3; i++) {
750 		flush_scheduled_work();
751 		led_classdev_unregister(&data->blinkm_leds[i].led_cdev);
752 	}
753 
754 	/* reset rgb */
755 	data->next_red = 0x00;
756 	data->next_green = 0x00;
757 	data->next_blue = 0x00;
758 	ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
759 	if (ret < 0)
760 		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
761 
762 	/* reset hsb */
763 	data->next_hue = 0x00;
764 	data->next_saturation = 0x00;
765 	data->next_brightness = 0x00;
766 	ret = blinkm_transfer_hw(client, BLM_FADE_HSB);
767 	if (ret < 0)
768 		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
769 
770 	/* red fade to off */
771 	data->next_red = 0xff;
772 	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
773 	if (ret < 0)
774 		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
775 
776 	/* off */
777 	data->next_red = 0x00;
778 	ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
779 	if (ret < 0)
780 		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
781 
782 	sysfs_remove_group(&client->dev.kobj, &blinkm_group);
783 	return 0;
784 }
785 
786 static const struct i2c_device_id blinkm_id[] = {
787 	{"blinkm", 0},
788 	{}
789 };
790 
791 MODULE_DEVICE_TABLE(i2c, blinkm_id);
792 
793   /* This is the driver that will be inserted */
794 static struct i2c_driver blinkm_driver = {
795 	.class = I2C_CLASS_HWMON,
796 	.driver = {
797 		   .name = "blinkm",
798 		   },
799 	.probe = blinkm_probe,
800 	.remove = blinkm_remove,
801 	.id_table = blinkm_id,
802 	.detect = blinkm_detect,
803 	.address_list = normal_i2c,
804 };
805 
806 module_i2c_driver(blinkm_driver);
807 
808 MODULE_AUTHOR("Jan-Simon Moeller <dl9pf@gmx.de>");
809 MODULE_DESCRIPTION("BlinkM RGB LED driver");
810 MODULE_LICENSE("GPL");
811 
812