xref: /openbmc/linux/drivers/leds/leds-blinkm.c (revision 79f08d9e)
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/init.h>
22 #include <linux/slab.h>
23 #include <linux/jiffies.h>
24 #include <linux/i2c.h>
25 #include <linux/err.h>
26 #include <linux/mutex.h>
27 #include <linux/sysfs.h>
28 #include <linux/printk.h>
29 #include <linux/pm_runtime.h>
30 #include <linux/leds.h>
31 #include <linux/delay.h>
32 
33 /* Addresses to scan - BlinkM is on 0x09 by default*/
34 static const unsigned short normal_i2c[] = { 0x09, I2C_CLIENT_END };
35 
36 static int blinkm_transfer_hw(struct i2c_client *client, int cmd);
37 static int blinkm_test_run(struct i2c_client *client);
38 
39 struct blinkm_led {
40 	struct i2c_client *i2c_client;
41 	struct led_classdev led_cdev;
42 	int id;
43 	atomic_t active;
44 };
45 
46 struct blinkm_work {
47 	struct blinkm_led *blinkm_led;
48 	struct work_struct work;
49 };
50 
51 #define cdev_to_blmled(c)          container_of(c, struct blinkm_led, led_cdev)
52 #define work_to_blmwork(c)         container_of(c, struct blinkm_work, work)
53 
54 struct blinkm_data {
55 	struct i2c_client *i2c_client;
56 	struct mutex update_lock;
57 	/* used for led class interface */
58 	struct blinkm_led blinkm_leds[3];
59 	/* used for "blinkm" sysfs interface */
60 	u8 red;			/* color red */
61 	u8 green;		/* color green */
62 	u8 blue;		/* color blue */
63 	/* next values to use for transfer */
64 	u8 next_red;			/* color red */
65 	u8 next_green;		/* color green */
66 	u8 next_blue;		/* color blue */
67 	/* internal use */
68 	u8 args[7];		/* set of args for transmission */
69 	u8 i2c_addr;		/* i2c addr */
70 	u8 fw_ver;		/* firmware version */
71 	/* used, but not from userspace */
72 	u8 hue;			/* HSB  hue */
73 	u8 saturation;		/* HSB  saturation */
74 	u8 brightness;		/* HSB  brightness */
75 	u8 next_hue;			/* HSB  hue */
76 	u8 next_saturation;		/* HSB  saturation */
77 	u8 next_brightness;		/* HSB  brightness */
78 	/* currently unused / todo */
79 	u8 fade_speed;		/* fade speed     1 - 255 */
80 	s8 time_adjust;		/* time adjust -128 - 127 */
81 	u8 fade:1;		/* fade on = 1, off = 0 */
82 	u8 rand:1;		/* rand fade mode on = 1 */
83 	u8 script_id;		/* script ID */
84 	u8 script_repeats;	/* repeats of script */
85 	u8 script_startline;	/* line to start */
86 };
87 
88 /* Colors */
89 #define RED   0
90 #define GREEN 1
91 #define BLUE  2
92 
93 /* mapping command names to cmd chars - see datasheet */
94 #define BLM_GO_RGB            0
95 #define BLM_FADE_RGB          1
96 #define BLM_FADE_HSB          2
97 #define BLM_FADE_RAND_RGB     3
98 #define BLM_FADE_RAND_HSB     4
99 #define BLM_PLAY_SCRIPT       5
100 #define BLM_STOP_SCRIPT       6
101 #define BLM_SET_FADE_SPEED    7
102 #define BLM_SET_TIME_ADJ      8
103 #define BLM_GET_CUR_RGB       9
104 #define BLM_WRITE_SCRIPT_LINE 10
105 #define BLM_READ_SCRIPT_LINE  11
106 #define BLM_SET_SCRIPT_LR     12	/* Length & Repeats */
107 #define BLM_SET_ADDR          13
108 #define BLM_GET_ADDR          14
109 #define BLM_GET_FW_VER        15
110 #define BLM_SET_STARTUP_PARAM 16
111 
112 /* BlinkM Commands
113  *  as extracted out of the datasheet:
114  *
115  *  cmdchar = command (ascii)
116  *  cmdbyte = command in hex
117  *  nr_args = number of arguments (to send)
118  *  nr_ret  = number of return values (to read)
119  *  dir = direction (0 = read, 1 = write, 2 = both)
120  *
121  */
122 static const struct {
123 	char cmdchar;
124 	u8 cmdbyte;
125 	u8 nr_args;
126 	u8 nr_ret;
127 	u8 dir:2;
128 } blinkm_cmds[17] = {
129   /* cmdchar, cmdbyte, nr_args, nr_ret,  dir */
130 	{ 'n', 0x6e, 3, 0, 1},
131 	{ 'c', 0x63, 3, 0, 1},
132 	{ 'h', 0x68, 3, 0, 1},
133 	{ 'C', 0x43, 3, 0, 1},
134 	{ 'H', 0x48, 3, 0, 1},
135 	{ 'p', 0x70, 3, 0, 1},
136 	{ 'o', 0x6f, 0, 0, 1},
137 	{ 'f', 0x66, 1, 0, 1},
138 	{ 't', 0x74, 1, 0, 1},
139 	{ 'g', 0x67, 0, 3, 0},
140 	{ 'W', 0x57, 7, 0, 1},
141 	{ 'R', 0x52, 2, 5, 2},
142 	{ 'L', 0x4c, 3, 0, 1},
143 	{ 'A', 0x41, 4, 0, 1},
144 	{ 'a', 0x61, 0, 1, 0},
145 	{ 'Z', 0x5a, 0, 1, 0},
146 	{ 'B', 0x42, 5, 0, 1},
147 };
148 
149 static ssize_t show_color_common(struct device *dev, char *buf, int color)
150 {
151 	struct i2c_client *client;
152 	struct blinkm_data *data;
153 	int ret;
154 
155 	client = to_i2c_client(dev);
156 	data = i2c_get_clientdata(client);
157 
158 	ret = blinkm_transfer_hw(client, BLM_GET_CUR_RGB);
159 	if (ret < 0)
160 		return ret;
161 	switch (color) {
162 	case RED:
163 		return scnprintf(buf, PAGE_SIZE, "%02X\n", data->red);
164 	case GREEN:
165 		return scnprintf(buf, PAGE_SIZE, "%02X\n", data->green);
166 	case BLUE:
167 		return scnprintf(buf, PAGE_SIZE, "%02X\n", data->blue);
168 	default:
169 		return -EINVAL;
170 	}
171 	return -EINVAL;
172 }
173 
174 static int store_color_common(struct device *dev, const char *buf, int color)
175 {
176 	struct i2c_client *client;
177 	struct blinkm_data *data;
178 	int ret;
179 	u8 value;
180 
181 	client = to_i2c_client(dev);
182 	data = i2c_get_clientdata(client);
183 
184 	ret = kstrtou8(buf, 10, &value);
185 	if (ret < 0) {
186 		dev_err(dev, "BlinkM: value too large!\n");
187 		return ret;
188 	}
189 
190 	switch (color) {
191 	case RED:
192 		data->next_red = value;
193 		break;
194 	case GREEN:
195 		data->next_green = value;
196 		break;
197 	case BLUE:
198 		data->next_blue = value;
199 		break;
200 	default:
201 		return -EINVAL;
202 	}
203 
204 	dev_dbg(dev, "next_red = %d, next_green = %d, next_blue = %d\n",
205 			data->next_red, data->next_green, data->next_blue);
206 
207 	/* if mode ... */
208 	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
209 	if (ret < 0) {
210 		dev_err(dev, "BlinkM: can't set RGB\n");
211 		return ret;
212 	}
213 	return 0;
214 }
215 
216 static ssize_t show_red(struct device *dev, struct device_attribute *attr,
217 			char *buf)
218 {
219 	return show_color_common(dev, buf, RED);
220 }
221 
222 static ssize_t store_red(struct device *dev, struct device_attribute *attr,
223 			 const char *buf, size_t count)
224 {
225 	int ret;
226 
227 	ret = store_color_common(dev, buf, RED);
228 	if (ret < 0)
229 		return ret;
230 	return count;
231 }
232 
233 static DEVICE_ATTR(red, S_IRUGO | S_IWUSR, show_red, store_red);
234 
235 static ssize_t show_green(struct device *dev, struct device_attribute *attr,
236 			  char *buf)
237 {
238 	return show_color_common(dev, buf, GREEN);
239 }
240 
241 static ssize_t store_green(struct device *dev, struct device_attribute *attr,
242 			   const char *buf, size_t count)
243 {
244 
245 	int ret;
246 
247 	ret = store_color_common(dev, buf, GREEN);
248 	if (ret < 0)
249 		return ret;
250 	return count;
251 }
252 
253 static DEVICE_ATTR(green, S_IRUGO | S_IWUSR, show_green, store_green);
254 
255 static ssize_t show_blue(struct device *dev, struct device_attribute *attr,
256 			 char *buf)
257 {
258 	return show_color_common(dev, buf, BLUE);
259 }
260 
261 static ssize_t store_blue(struct device *dev, struct device_attribute *attr,
262 			  const char *buf, size_t count)
263 {
264 	int ret;
265 
266 	ret = store_color_common(dev, buf, BLUE);
267 	if (ret < 0)
268 		return ret;
269 	return count;
270 }
271 
272 static DEVICE_ATTR(blue, S_IRUGO | S_IWUSR, show_blue, store_blue);
273 
274 static ssize_t show_test(struct device *dev, struct device_attribute *attr,
275 			 char *buf)
276 {
277 	return scnprintf(buf, PAGE_SIZE,
278 			 "#Write into test to start test sequence!#\n");
279 }
280 
281 static ssize_t store_test(struct device *dev, struct device_attribute *attr,
282 			  const char *buf, size_t count)
283 {
284 
285 	struct i2c_client *client;
286 	int ret;
287 	client = to_i2c_client(dev);
288 
289 	/*test */
290 	ret = blinkm_test_run(client);
291 	if (ret < 0)
292 		return ret;
293 
294 	return count;
295 }
296 
297 static DEVICE_ATTR(test, S_IRUGO | S_IWUSR, show_test, store_test);
298 
299 /* TODO: HSB, fade, timeadj, script ... */
300 
301 static struct attribute *blinkm_attrs[] = {
302 	&dev_attr_red.attr,
303 	&dev_attr_green.attr,
304 	&dev_attr_blue.attr,
305 	&dev_attr_test.attr,
306 	NULL,
307 };
308 
309 static struct attribute_group blinkm_group = {
310 	.name = "blinkm",
311 	.attrs = blinkm_attrs,
312 };
313 
314 static int blinkm_write(struct i2c_client *client, int cmd, u8 *arg)
315 {
316 	int result;
317 	int i;
318 	int arglen = blinkm_cmds[cmd].nr_args;
319 	/* write out cmd to blinkm - always / default step */
320 	result = i2c_smbus_write_byte(client, blinkm_cmds[cmd].cmdbyte);
321 	if (result < 0)
322 		return result;
323 	/* no args to write out */
324 	if (arglen == 0)
325 		return 0;
326 
327 	for (i = 0; i < arglen; i++) {
328 		/* repeat for arglen */
329 		result = i2c_smbus_write_byte(client, arg[i]);
330 		if (result < 0)
331 			return result;
332 	}
333 	return 0;
334 }
335 
336 static int blinkm_read(struct i2c_client *client, int cmd, u8 *arg)
337 {
338 	int result;
339 	int i;
340 	int retlen = blinkm_cmds[cmd].nr_ret;
341 	for (i = 0; i < retlen; i++) {
342 		/* repeat for retlen */
343 		result = i2c_smbus_read_byte(client);
344 		if (result < 0)
345 			return result;
346 		arg[i] = result;
347 	}
348 
349 	return 0;
350 }
351 
352 static int blinkm_transfer_hw(struct i2c_client *client, int cmd)
353 {
354 	/* the protocol is simple but non-standard:
355 	 * e.g.  cmd 'g' (= 0x67) for "get device address"
356 	 * - which defaults to 0x09 - would be the sequence:
357 	 *   a) write 0x67 to the device (byte write)
358 	 *   b) read the value (0x09) back right after (byte read)
359 	 *
360 	 * Watch out for "unfinished" sequences (i.e. not enough reads
361 	 * or writes after a command. It will make the blinkM misbehave.
362 	 * Sequence is key here.
363 	 */
364 
365 	/* args / return are in private data struct */
366 	struct blinkm_data *data = i2c_get_clientdata(client);
367 
368 	/* We start hardware transfers which are not to be
369 	 * mixed with other commands. Aquire a lock now. */
370 	if (mutex_lock_interruptible(&data->update_lock) < 0)
371 		return -EAGAIN;
372 
373 	/* switch cmd - usually write before reads */
374 	switch (cmd) {
375 	case BLM_FADE_RAND_RGB:
376 	case BLM_GO_RGB:
377 	case BLM_FADE_RGB:
378 		data->args[0] = data->next_red;
379 		data->args[1] = data->next_green;
380 		data->args[2] = data->next_blue;
381 		blinkm_write(client, cmd, data->args);
382 		data->red = data->args[0];
383 		data->green = data->args[1];
384 		data->blue = data->args[2];
385 		break;
386 	case BLM_FADE_HSB:
387 	case BLM_FADE_RAND_HSB:
388 		data->args[0] = data->next_hue;
389 		data->args[1] = data->next_saturation;
390 		data->args[2] = data->next_brightness;
391 		blinkm_write(client, cmd, data->args);
392 		data->hue = data->next_hue;
393 		data->saturation = data->next_saturation;
394 		data->brightness = data->next_brightness;
395 		break;
396 	case BLM_PLAY_SCRIPT:
397 		data->args[0] = data->script_id;
398 		data->args[1] = data->script_repeats;
399 		data->args[2] = data->script_startline;
400 		blinkm_write(client, cmd, data->args);
401 		break;
402 	case BLM_STOP_SCRIPT:
403 		blinkm_write(client, cmd, NULL);
404 		break;
405 	case BLM_GET_CUR_RGB:
406 		data->args[0] = data->red;
407 		data->args[1] = data->green;
408 		data->args[2] = data->blue;
409 		blinkm_write(client, cmd, NULL);
410 		blinkm_read(client, cmd, data->args);
411 		data->red = data->args[0];
412 		data->green = data->args[1];
413 		data->blue = data->args[2];
414 		break;
415 	case BLM_GET_ADDR:
416 		data->args[0] = data->i2c_addr;
417 		blinkm_write(client, cmd, NULL);
418 		blinkm_read(client, cmd, data->args);
419 		data->i2c_addr = data->args[0];
420 		break;
421 	case BLM_SET_TIME_ADJ:
422 	case BLM_SET_FADE_SPEED:
423 	case BLM_READ_SCRIPT_LINE:
424 	case BLM_WRITE_SCRIPT_LINE:
425 	case BLM_SET_SCRIPT_LR:
426 	case BLM_SET_ADDR:
427 	case BLM_GET_FW_VER:
428 	case BLM_SET_STARTUP_PARAM:
429 		dev_err(&client->dev,
430 				"BlinkM: cmd %d not implemented yet.\n", cmd);
431 		break;
432 	default:
433 		dev_err(&client->dev, "BlinkM: unknown command %d\n", cmd);
434 		mutex_unlock(&data->update_lock);
435 		return -EINVAL;
436 	}			/* end switch(cmd) */
437 
438 	/* transfers done, unlock */
439 	mutex_unlock(&data->update_lock);
440 	return 0;
441 }
442 
443 static void led_work(struct work_struct *work)
444 {
445 	int ret;
446 	struct blinkm_led *led;
447 	struct blinkm_data *data ;
448 	struct blinkm_work *blm_work = work_to_blmwork(work);
449 
450 	led = blm_work->blinkm_led;
451 	data = i2c_get_clientdata(led->i2c_client);
452 	ret = blinkm_transfer_hw(led->i2c_client, BLM_GO_RGB);
453 	atomic_dec(&led->active);
454 	dev_dbg(&led->i2c_client->dev,
455 			"# DONE # next_red = %d, next_green = %d,"
456 			" next_blue = %d, active = %d\n",
457 			data->next_red, data->next_green,
458 			data->next_blue, atomic_read(&led->active));
459 	kfree(blm_work);
460 }
461 
462 static int blinkm_led_common_set(struct led_classdev *led_cdev,
463 				 enum led_brightness value, int color)
464 {
465 	/* led_brightness is 0, 127 or 255 - we just use it here as-is */
466 	struct blinkm_led *led = cdev_to_blmled(led_cdev);
467 	struct blinkm_data *data = i2c_get_clientdata(led->i2c_client);
468 	struct blinkm_work *bl_work;
469 
470 	switch (color) {
471 	case RED:
472 		/* bail out if there's no change */
473 		if (data->next_red == (u8) value)
474 			return 0;
475 		/* we assume a quite fast sequence here ([off]->on->off)
476 		 * think of network led trigger - we cannot blink that fast, so
477 		 * in case we already have a off->on->off transition queued up,
478 		 * we refuse to queue up more.
479 		 * Revisit: fast-changing brightness. */
480 		if (atomic_read(&led->active) > 1)
481 			return 0;
482 		data->next_red = (u8) value;
483 		break;
484 	case GREEN:
485 		/* bail out if there's no change */
486 		if (data->next_green == (u8) value)
487 			return 0;
488 		/* we assume a quite fast sequence here ([off]->on->off)
489 		 * Revisit: fast-changing brightness. */
490 		if (atomic_read(&led->active) > 1)
491 			return 0;
492 		data->next_green = (u8) value;
493 		break;
494 	case BLUE:
495 		/* bail out if there's no change */
496 		if (data->next_blue == (u8) value)
497 			return 0;
498 		/* we assume a quite fast sequence here ([off]->on->off)
499 		 * Revisit: fast-changing brightness. */
500 		if (atomic_read(&led->active) > 1)
501 			return 0;
502 		data->next_blue = (u8) value;
503 		break;
504 
505 	default:
506 		dev_err(&led->i2c_client->dev, "BlinkM: unknown color.\n");
507 		return -EINVAL;
508 	}
509 
510 	bl_work = kzalloc(sizeof(*bl_work), GFP_ATOMIC);
511 	if (!bl_work)
512 		return -ENOMEM;
513 
514 	atomic_inc(&led->active);
515 	dev_dbg(&led->i2c_client->dev,
516 			"#TO_SCHED# next_red = %d, next_green = %d,"
517 			" next_blue = %d, active = %d\n",
518 			data->next_red, data->next_green,
519 			data->next_blue, atomic_read(&led->active));
520 
521 	/* a fresh work _item_ for each change */
522 	bl_work->blinkm_led = led;
523 	INIT_WORK(&bl_work->work, led_work);
524 	/* queue work in own queue for easy sync on exit*/
525 	schedule_work(&bl_work->work);
526 
527 	return 0;
528 }
529 
530 static void blinkm_led_red_set(struct led_classdev *led_cdev,
531 			       enum led_brightness value)
532 {
533 	blinkm_led_common_set(led_cdev, value, RED);
534 }
535 
536 static void blinkm_led_green_set(struct led_classdev *led_cdev,
537 				 enum led_brightness value)
538 {
539 	blinkm_led_common_set(led_cdev, value, GREEN);
540 }
541 
542 static void blinkm_led_blue_set(struct led_classdev *led_cdev,
543 				enum led_brightness value)
544 {
545 	blinkm_led_common_set(led_cdev, value, BLUE);
546 }
547 
548 static void blinkm_init_hw(struct i2c_client *client)
549 {
550 	int ret;
551 	ret = blinkm_transfer_hw(client, BLM_STOP_SCRIPT);
552 	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
553 }
554 
555 static int blinkm_test_run(struct i2c_client *client)
556 {
557 	int ret;
558 	struct blinkm_data *data = i2c_get_clientdata(client);
559 
560 	data->next_red = 0x01;
561 	data->next_green = 0x05;
562 	data->next_blue = 0x10;
563 	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
564 	if (ret < 0)
565 		return ret;
566 	msleep(2000);
567 
568 	data->next_red = 0x25;
569 	data->next_green = 0x10;
570 	data->next_blue = 0x31;
571 	ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
572 	if (ret < 0)
573 		return ret;
574 	msleep(2000);
575 
576 	data->next_hue = 0x50;
577 	data->next_saturation = 0x10;
578 	data->next_brightness = 0x20;
579 	ret = blinkm_transfer_hw(client, BLM_FADE_HSB);
580 	if (ret < 0)
581 		return ret;
582 	msleep(2000);
583 
584 	return 0;
585 }
586 
587 /* Return 0 if detection is successful, -ENODEV otherwise */
588 static int blinkm_detect(struct i2c_client *client, struct i2c_board_info *info)
589 {
590 	struct i2c_adapter *adapter = client->adapter;
591 	int ret;
592 	int count = 99;
593 	u8 tmpargs[7];
594 
595 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
596 				     | I2C_FUNC_SMBUS_WORD_DATA
597 				     | I2C_FUNC_SMBUS_WRITE_BYTE))
598 		return -ENODEV;
599 
600 	/* Now, we do the remaining detection. Simple for now. */
601 	/* We might need more guards to protect other i2c slaves */
602 
603 	/* make sure the blinkM is balanced (read/writes) */
604 	while (count > 0) {
605 		ret = blinkm_write(client, BLM_GET_ADDR, NULL);
606 		usleep_range(5000, 10000);
607 		ret = blinkm_read(client, BLM_GET_ADDR, tmpargs);
608 		usleep_range(5000, 10000);
609 		if (tmpargs[0] == 0x09)
610 			count = 0;
611 		count--;
612 	}
613 
614 	/* Step 1: Read BlinkM address back  -  cmd_char 'a' */
615 	ret = blinkm_write(client, BLM_GET_ADDR, NULL);
616 	if (ret < 0)
617 		return ret;
618 	usleep_range(20000, 30000);	/* allow a small delay */
619 	ret = blinkm_read(client, BLM_GET_ADDR, tmpargs);
620 	if (ret < 0)
621 		return ret;
622 
623 	if (tmpargs[0] != 0x09) {
624 		dev_err(&client->dev, "enodev DEV ADDR = 0x%02X\n", tmpargs[0]);
625 		return -ENODEV;
626 	}
627 
628 	strlcpy(info->type, "blinkm", I2C_NAME_SIZE);
629 	return 0;
630 }
631 
632 static int blinkm_probe(struct i2c_client *client,
633 			const struct i2c_device_id *id)
634 {
635 	struct blinkm_data *data;
636 	struct blinkm_led *led[3];
637 	int err, i;
638 	char blinkm_led_name[28];
639 
640 	data = devm_kzalloc(&client->dev,
641 			sizeof(struct blinkm_data), GFP_KERNEL);
642 	if (!data) {
643 		err = -ENOMEM;
644 		goto exit;
645 	}
646 
647 	data->i2c_addr = 0x09;
648 	data->i2c_addr = 0x08;
649 	/* i2c addr  - use fake addr of 0x08 initially (real is 0x09) */
650 	data->fw_ver = 0xfe;
651 	/* firmware version - use fake until we read real value
652 	 * (currently broken - BlinkM confused!) */
653 	data->script_id = 0x01;
654 	data->i2c_client = client;
655 
656 	i2c_set_clientdata(client, data);
657 	mutex_init(&data->update_lock);
658 
659 	/* Register sysfs hooks */
660 	err = sysfs_create_group(&client->dev.kobj, &blinkm_group);
661 	if (err < 0) {
662 		dev_err(&client->dev, "couldn't register sysfs group\n");
663 		goto exit;
664 	}
665 
666 	for (i = 0; i < 3; i++) {
667 		/* RED = 0, GREEN = 1, BLUE = 2 */
668 		led[i] = &data->blinkm_leds[i];
669 		led[i]->i2c_client = client;
670 		led[i]->id = i;
671 		led[i]->led_cdev.max_brightness = 255;
672 		led[i]->led_cdev.flags = LED_CORE_SUSPENDRESUME;
673 		atomic_set(&led[i]->active, 0);
674 		switch (i) {
675 		case RED:
676 			snprintf(blinkm_led_name, sizeof(blinkm_led_name),
677 					 "blinkm-%d-%d-red",
678 					 client->adapter->nr,
679 					 client->addr);
680 			led[i]->led_cdev.name = blinkm_led_name;
681 			led[i]->led_cdev.brightness_set = blinkm_led_red_set;
682 			err = led_classdev_register(&client->dev,
683 						    &led[i]->led_cdev);
684 			if (err < 0) {
685 				dev_err(&client->dev,
686 					"couldn't register LED %s\n",
687 					led[i]->led_cdev.name);
688 				goto failred;
689 			}
690 			break;
691 		case GREEN:
692 			snprintf(blinkm_led_name, sizeof(blinkm_led_name),
693 					 "blinkm-%d-%d-green",
694 					 client->adapter->nr,
695 					 client->addr);
696 			led[i]->led_cdev.name = blinkm_led_name;
697 			led[i]->led_cdev.brightness_set = blinkm_led_green_set;
698 			err = led_classdev_register(&client->dev,
699 						    &led[i]->led_cdev);
700 			if (err < 0) {
701 				dev_err(&client->dev,
702 					"couldn't register LED %s\n",
703 					led[i]->led_cdev.name);
704 				goto failgreen;
705 			}
706 			break;
707 		case BLUE:
708 			snprintf(blinkm_led_name, sizeof(blinkm_led_name),
709 					 "blinkm-%d-%d-blue",
710 					 client->adapter->nr,
711 					 client->addr);
712 			led[i]->led_cdev.name = blinkm_led_name;
713 			led[i]->led_cdev.brightness_set = blinkm_led_blue_set;
714 			err = led_classdev_register(&client->dev,
715 						    &led[i]->led_cdev);
716 			if (err < 0) {
717 				dev_err(&client->dev,
718 					"couldn't register LED %s\n",
719 					led[i]->led_cdev.name);
720 				goto failblue;
721 			}
722 			break;
723 		}		/* end switch */
724 	}			/* end for */
725 
726 	/* Initialize the blinkm */
727 	blinkm_init_hw(client);
728 
729 	return 0;
730 
731 failblue:
732 	led_classdev_unregister(&led[GREEN]->led_cdev);
733 
734 failgreen:
735 	led_classdev_unregister(&led[RED]->led_cdev);
736 
737 failred:
738 	sysfs_remove_group(&client->dev.kobj, &blinkm_group);
739 exit:
740 	return err;
741 }
742 
743 static int blinkm_remove(struct i2c_client *client)
744 {
745 	struct blinkm_data *data = i2c_get_clientdata(client);
746 	int ret = 0;
747 	int i;
748 
749 	/* make sure no workqueue entries are pending */
750 	for (i = 0; i < 3; i++) {
751 		flush_scheduled_work();
752 		led_classdev_unregister(&data->blinkm_leds[i].led_cdev);
753 	}
754 
755 	/* reset rgb */
756 	data->next_red = 0x00;
757 	data->next_green = 0x00;
758 	data->next_blue = 0x00;
759 	ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
760 	if (ret < 0)
761 		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
762 
763 	/* reset hsb */
764 	data->next_hue = 0x00;
765 	data->next_saturation = 0x00;
766 	data->next_brightness = 0x00;
767 	ret = blinkm_transfer_hw(client, BLM_FADE_HSB);
768 	if (ret < 0)
769 		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
770 
771 	/* red fade to off */
772 	data->next_red = 0xff;
773 	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
774 	if (ret < 0)
775 		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
776 
777 	/* off */
778 	data->next_red = 0x00;
779 	ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
780 	if (ret < 0)
781 		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
782 
783 	sysfs_remove_group(&client->dev.kobj, &blinkm_group);
784 	return 0;
785 }
786 
787 static const struct i2c_device_id blinkm_id[] = {
788 	{"blinkm", 0},
789 	{}
790 };
791 
792 MODULE_DEVICE_TABLE(i2c, blinkm_id);
793 
794   /* This is the driver that will be inserted */
795 static struct i2c_driver blinkm_driver = {
796 	.class = I2C_CLASS_HWMON,
797 	.driver = {
798 		   .name = "blinkm",
799 		   },
800 	.probe = blinkm_probe,
801 	.remove = blinkm_remove,
802 	.id_table = blinkm_id,
803 	.detect = blinkm_detect,
804 	.address_list = normal_i2c,
805 };
806 
807 module_i2c_driver(blinkm_driver);
808 
809 MODULE_AUTHOR("Jan-Simon Moeller <dl9pf@gmx.de>");
810 MODULE_DESCRIPTION("BlinkM RGB LED driver");
811 MODULE_LICENSE("GPL");
812 
813