xref: /linux/drivers/leds/leds-blinkm.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
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 		break;
165 	case GREEN:
166 		return scnprintf(buf, PAGE_SIZE, "%02X\n", data->green);
167 		break;
168 	case BLUE:
169 		return scnprintf(buf, PAGE_SIZE, "%02X\n", data->blue);
170 		break;
171 	default:
172 		return -EINVAL;
173 	}
174 	return -EINVAL;
175 }
176 
177 static int store_color_common(struct device *dev, const char *buf, int color)
178 {
179 	struct i2c_client *client;
180 	struct blinkm_data *data;
181 	int ret;
182 	u8 value;
183 
184 	client = to_i2c_client(dev);
185 	data = i2c_get_clientdata(client);
186 
187 	ret = kstrtou8(buf, 10, &value);
188 	if (ret < 0) {
189 		dev_err(dev, "BlinkM: value too large!\n");
190 		return ret;
191 	}
192 
193 	switch (color) {
194 	case RED:
195 		data->next_red = value;
196 		break;
197 	case GREEN:
198 		data->next_green = value;
199 		break;
200 	case BLUE:
201 		data->next_blue = value;
202 		break;
203 	default:
204 		return -EINVAL;
205 	}
206 
207 	dev_dbg(dev, "next_red = %d, next_green = %d, next_blue = %d\n",
208 			data->next_red, data->next_green, data->next_blue);
209 
210 	/* if mode ... */
211 	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
212 	if (ret < 0) {
213 		dev_err(dev, "BlinkM: can't set RGB\n");
214 		return ret;
215 	}
216 	return 0;
217 }
218 
219 static ssize_t show_red(struct device *dev, struct device_attribute *attr,
220 			char *buf)
221 {
222 	return show_color_common(dev, buf, RED);
223 }
224 
225 static ssize_t store_red(struct device *dev, struct device_attribute *attr,
226 			 const char *buf, size_t count)
227 {
228 	int ret;
229 
230 	ret = store_color_common(dev, buf, RED);
231 	if (ret < 0)
232 		return ret;
233 	return count;
234 }
235 
236 static DEVICE_ATTR(red, S_IRUGO | S_IWUSR, show_red, store_red);
237 
238 static ssize_t show_green(struct device *dev, struct device_attribute *attr,
239 			  char *buf)
240 {
241 	return show_color_common(dev, buf, GREEN);
242 }
243 
244 static ssize_t store_green(struct device *dev, struct device_attribute *attr,
245 			   const char *buf, size_t count)
246 {
247 
248 	int ret;
249 
250 	ret = store_color_common(dev, buf, GREEN);
251 	if (ret < 0)
252 		return ret;
253 	return count;
254 }
255 
256 static DEVICE_ATTR(green, S_IRUGO | S_IWUSR, show_green, store_green);
257 
258 static ssize_t show_blue(struct device *dev, struct device_attribute *attr,
259 			 char *buf)
260 {
261 	return show_color_common(dev, buf, BLUE);
262 }
263 
264 static ssize_t store_blue(struct device *dev, struct device_attribute *attr,
265 			  const char *buf, size_t count)
266 {
267 	int ret;
268 
269 	ret = store_color_common(dev, buf, BLUE);
270 	if (ret < 0)
271 		return ret;
272 	return count;
273 }
274 
275 static DEVICE_ATTR(blue, S_IRUGO | S_IWUSR, show_blue, store_blue);
276 
277 static ssize_t show_test(struct device *dev, struct device_attribute *attr,
278 			 char *buf)
279 {
280 	return scnprintf(buf, PAGE_SIZE,
281 			 "#Write into test to start test sequence!#\n");
282 }
283 
284 static ssize_t store_test(struct device *dev, struct device_attribute *attr,
285 			  const char *buf, size_t count)
286 {
287 
288 	struct i2c_client *client;
289 	int ret;
290 	client = to_i2c_client(dev);
291 
292 	/*test */
293 	ret = blinkm_test_run(client);
294 	if (ret < 0)
295 		return ret;
296 
297 	return count;
298 }
299 
300 static DEVICE_ATTR(test, S_IRUGO | S_IWUSR, show_test, store_test);
301 
302 /* TODO: HSB, fade, timeadj, script ... */
303 
304 static struct attribute *blinkm_attrs[] = {
305 	&dev_attr_red.attr,
306 	&dev_attr_green.attr,
307 	&dev_attr_blue.attr,
308 	&dev_attr_test.attr,
309 	NULL,
310 };
311 
312 static struct attribute_group blinkm_group = {
313 	.name = "blinkm",
314 	.attrs = blinkm_attrs,
315 };
316 
317 static int blinkm_write(struct i2c_client *client, int cmd, u8 *arg)
318 {
319 	int result;
320 	int i;
321 	int arglen = blinkm_cmds[cmd].nr_args;
322 	/* write out cmd to blinkm - always / default step */
323 	result = i2c_smbus_write_byte(client, blinkm_cmds[cmd].cmdbyte);
324 	if (result < 0)
325 		return result;
326 	/* no args to write out */
327 	if (arglen == 0)
328 		return 0;
329 
330 	for (i = 0; i < arglen; i++) {
331 		/* repeat for arglen */
332 		result = i2c_smbus_write_byte(client, arg[i]);
333 		if (result < 0)
334 			return result;
335 	}
336 	return 0;
337 }
338 
339 static int blinkm_read(struct i2c_client *client, int cmd, u8 *arg)
340 {
341 	int result;
342 	int i;
343 	int retlen = blinkm_cmds[cmd].nr_ret;
344 	for (i = 0; i < retlen; i++) {
345 		/* repeat for retlen */
346 		result = i2c_smbus_read_byte(client);
347 		if (result < 0)
348 			return result;
349 		arg[i] = result;
350 	}
351 
352 	return 0;
353 }
354 
355 static int blinkm_transfer_hw(struct i2c_client *client, int cmd)
356 {
357 	/* the protocol is simple but non-standard:
358 	 * e.g.  cmd 'g' (= 0x67) for "get device address"
359 	 * - which defaults to 0x09 - would be the sequence:
360 	 *   a) write 0x67 to the device (byte write)
361 	 *   b) read the value (0x09) back right after (byte read)
362 	 *
363 	 * Watch out for "unfinished" sequences (i.e. not enough reads
364 	 * or writes after a command. It will make the blinkM misbehave.
365 	 * Sequence is key here.
366 	 */
367 
368 	/* args / return are in private data struct */
369 	struct blinkm_data *data = i2c_get_clientdata(client);
370 
371 	/* We start hardware transfers which are not to be
372 	 * mixed with other commands. Aquire a lock now. */
373 	if (mutex_lock_interruptible(&data->update_lock) < 0)
374 		return -EAGAIN;
375 
376 	/* switch cmd - usually write before reads */
377 	switch (cmd) {
378 	case BLM_FADE_RAND_RGB:
379 	case BLM_GO_RGB:
380 	case BLM_FADE_RGB:
381 		data->args[0] = data->next_red;
382 		data->args[1] = data->next_green;
383 		data->args[2] = data->next_blue;
384 		blinkm_write(client, cmd, data->args);
385 		data->red = data->args[0];
386 		data->green = data->args[1];
387 		data->blue = data->args[2];
388 		break;
389 	case BLM_FADE_HSB:
390 	case BLM_FADE_RAND_HSB:
391 		data->args[0] = data->next_hue;
392 		data->args[1] = data->next_saturation;
393 		data->args[2] = data->next_brightness;
394 		blinkm_write(client, cmd, data->args);
395 		data->hue = data->next_hue;
396 		data->saturation = data->next_saturation;
397 		data->brightness = data->next_brightness;
398 		break;
399 	case BLM_PLAY_SCRIPT:
400 		data->args[0] = data->script_id;
401 		data->args[1] = data->script_repeats;
402 		data->args[2] = data->script_startline;
403 		blinkm_write(client, cmd, data->args);
404 		break;
405 	case BLM_STOP_SCRIPT:
406 		blinkm_write(client, cmd, NULL);
407 		break;
408 	case BLM_GET_CUR_RGB:
409 		data->args[0] = data->red;
410 		data->args[1] = data->green;
411 		data->args[2] = data->blue;
412 		blinkm_write(client, cmd, NULL);
413 		blinkm_read(client, cmd, data->args);
414 		data->red = data->args[0];
415 		data->green = data->args[1];
416 		data->blue = data->args[2];
417 		break;
418 	case BLM_GET_ADDR:
419 		data->args[0] = data->i2c_addr;
420 		blinkm_write(client, cmd, NULL);
421 		blinkm_read(client, cmd, data->args);
422 		data->i2c_addr = data->args[0];
423 		break;
424 	case BLM_SET_TIME_ADJ:
425 	case BLM_SET_FADE_SPEED:
426 	case BLM_READ_SCRIPT_LINE:
427 	case BLM_WRITE_SCRIPT_LINE:
428 	case BLM_SET_SCRIPT_LR:
429 	case BLM_SET_ADDR:
430 	case BLM_GET_FW_VER:
431 	case BLM_SET_STARTUP_PARAM:
432 		dev_err(&client->dev,
433 				"BlinkM: cmd %d not implemented yet.\n", cmd);
434 		break;
435 	default:
436 		dev_err(&client->dev, "BlinkM: unknown command %d\n", cmd);
437 		mutex_unlock(&data->update_lock);
438 		return -EINVAL;
439 	}			/* end switch(cmd) */
440 
441 	/* transfers done, unlock */
442 	mutex_unlock(&data->update_lock);
443 	return 0;
444 }
445 
446 static void led_work(struct work_struct *work)
447 {
448 	int ret;
449 	struct blinkm_led *led;
450 	struct blinkm_data *data ;
451 	struct blinkm_work *blm_work = work_to_blmwork(work);
452 
453 	led = blm_work->blinkm_led;
454 	data = i2c_get_clientdata(led->i2c_client);
455 	ret = blinkm_transfer_hw(led->i2c_client, BLM_GO_RGB);
456 	atomic_dec(&led->active);
457 	dev_dbg(&led->i2c_client->dev,
458 			"# DONE # next_red = %d, next_green = %d,"
459 			" next_blue = %d, active = %d\n",
460 			data->next_red, data->next_green,
461 			data->next_blue, atomic_read(&led->active));
462 	kfree(blm_work);
463 }
464 
465 static int blinkm_led_common_set(struct led_classdev *led_cdev,
466 				 enum led_brightness value, int color)
467 {
468 	/* led_brightness is 0, 127 or 255 - we just use it here as-is */
469 	struct blinkm_led *led = cdev_to_blmled(led_cdev);
470 	struct blinkm_data *data = i2c_get_clientdata(led->i2c_client);
471 	struct blinkm_work *bl_work;
472 
473 	switch (color) {
474 	case RED:
475 		/* bail out if there's no change */
476 		if (data->next_red == (u8) value)
477 			return 0;
478 		/* we assume a quite fast sequence here ([off]->on->off)
479 		 * think of network led trigger - we cannot blink that fast, so
480 		 * in case we already have a off->on->off transition queued up,
481 		 * we refuse to queue up more.
482 		 * Revisit: fast-changing brightness. */
483 		if (atomic_read(&led->active) > 1)
484 			return 0;
485 		data->next_red = (u8) value;
486 		break;
487 	case GREEN:
488 		/* bail out if there's no change */
489 		if (data->next_green == (u8) value)
490 			return 0;
491 		/* we assume a quite fast sequence here ([off]->on->off)
492 		 * Revisit: fast-changing brightness. */
493 		if (atomic_read(&led->active) > 1)
494 			return 0;
495 		data->next_green = (u8) value;
496 		break;
497 	case BLUE:
498 		/* bail out if there's no change */
499 		if (data->next_blue == (u8) value)
500 			return 0;
501 		/* we assume a quite fast sequence here ([off]->on->off)
502 		 * Revisit: fast-changing brightness. */
503 		if (atomic_read(&led->active) > 1)
504 			return 0;
505 		data->next_blue = (u8) value;
506 		break;
507 
508 	default:
509 		dev_err(&led->i2c_client->dev, "BlinkM: unknown color.\n");
510 		return -EINVAL;
511 	}
512 
513 	bl_work = kzalloc(sizeof(*bl_work), GFP_ATOMIC);
514 	if (!bl_work)
515 		return -ENOMEM;
516 
517 	atomic_inc(&led->active);
518 	dev_dbg(&led->i2c_client->dev,
519 			"#TO_SCHED# next_red = %d, next_green = %d,"
520 			" next_blue = %d, active = %d\n",
521 			data->next_red, data->next_green,
522 			data->next_blue, atomic_read(&led->active));
523 
524 	/* a fresh work _item_ for each change */
525 	bl_work->blinkm_led = led;
526 	INIT_WORK(&bl_work->work, led_work);
527 	/* queue work in own queue for easy sync on exit*/
528 	schedule_work(&bl_work->work);
529 
530 	return 0;
531 }
532 
533 static void blinkm_led_red_set(struct led_classdev *led_cdev,
534 			       enum led_brightness value)
535 {
536 	blinkm_led_common_set(led_cdev, value, RED);
537 }
538 
539 static void blinkm_led_green_set(struct led_classdev *led_cdev,
540 				 enum led_brightness value)
541 {
542 	blinkm_led_common_set(led_cdev, value, GREEN);
543 }
544 
545 static void blinkm_led_blue_set(struct led_classdev *led_cdev,
546 				enum led_brightness value)
547 {
548 	blinkm_led_common_set(led_cdev, value, BLUE);
549 }
550 
551 static void blinkm_init_hw(struct i2c_client *client)
552 {
553 	int ret;
554 	ret = blinkm_transfer_hw(client, BLM_STOP_SCRIPT);
555 	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
556 }
557 
558 static int blinkm_test_run(struct i2c_client *client)
559 {
560 	int ret;
561 	struct blinkm_data *data = i2c_get_clientdata(client);
562 
563 	data->next_red = 0x01;
564 	data->next_green = 0x05;
565 	data->next_blue = 0x10;
566 	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
567 	if (ret < 0)
568 		return ret;
569 	msleep(2000);
570 
571 	data->next_red = 0x25;
572 	data->next_green = 0x10;
573 	data->next_blue = 0x31;
574 	ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
575 	if (ret < 0)
576 		return ret;
577 	msleep(2000);
578 
579 	data->next_hue = 0x50;
580 	data->next_saturation = 0x10;
581 	data->next_brightness = 0x20;
582 	ret = blinkm_transfer_hw(client, BLM_FADE_HSB);
583 	if (ret < 0)
584 		return ret;
585 	msleep(2000);
586 
587 	return 0;
588 }
589 
590 /* Return 0 if detection is successful, -ENODEV otherwise */
591 static int blinkm_detect(struct i2c_client *client, struct i2c_board_info *info)
592 {
593 	struct i2c_adapter *adapter = client->adapter;
594 	int ret;
595 	int count = 99;
596 	u8 tmpargs[7];
597 
598 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
599 				     | I2C_FUNC_SMBUS_WORD_DATA
600 				     | I2C_FUNC_SMBUS_WRITE_BYTE))
601 		return -ENODEV;
602 
603 	/* Now, we do the remaining detection. Simple for now. */
604 	/* We might need more guards to protect other i2c slaves */
605 
606 	/* make sure the blinkM is balanced (read/writes) */
607 	while (count > 0) {
608 		ret = blinkm_write(client, BLM_GET_ADDR, NULL);
609 		usleep_range(5000, 10000);
610 		ret = blinkm_read(client, BLM_GET_ADDR, tmpargs);
611 		usleep_range(5000, 10000);
612 		if (tmpargs[0] == 0x09)
613 			count = 0;
614 		count--;
615 	}
616 
617 	/* Step 1: Read BlinkM address back  -  cmd_char 'a' */
618 	ret = blinkm_write(client, BLM_GET_ADDR, NULL);
619 	if (ret < 0)
620 		return ret;
621 	usleep_range(20000, 30000);	/* allow a small delay */
622 	ret = blinkm_read(client, BLM_GET_ADDR, tmpargs);
623 	if (ret < 0)
624 		return ret;
625 
626 	if (tmpargs[0] != 0x09) {
627 		dev_err(&client->dev, "enodev DEV ADDR = 0x%02X\n", tmpargs[0]);
628 		return -ENODEV;
629 	}
630 
631 	strlcpy(info->type, "blinkm", I2C_NAME_SIZE);
632 	return 0;
633 }
634 
635 static int blinkm_probe(struct i2c_client *client,
636 			const struct i2c_device_id *id)
637 {
638 	struct blinkm_data *data;
639 	struct blinkm_led *led[3];
640 	int err, i;
641 	char blinkm_led_name[28];
642 
643 	data = devm_kzalloc(&client->dev,
644 			sizeof(struct blinkm_data), GFP_KERNEL);
645 	if (!data) {
646 		err = -ENOMEM;
647 		goto exit;
648 	}
649 
650 	data->i2c_addr = 0x09;
651 	data->i2c_addr = 0x08;
652 	/* i2c addr  - use fake addr of 0x08 initially (real is 0x09) */
653 	data->fw_ver = 0xfe;
654 	/* firmware version - use fake until we read real value
655 	 * (currently broken - BlinkM confused!) */
656 	data->script_id = 0x01;
657 	data->i2c_client = client;
658 
659 	i2c_set_clientdata(client, data);
660 	mutex_init(&data->update_lock);
661 
662 	/* Register sysfs hooks */
663 	err = sysfs_create_group(&client->dev.kobj, &blinkm_group);
664 	if (err < 0) {
665 		dev_err(&client->dev, "couldn't register sysfs group\n");
666 		goto exit;
667 	}
668 
669 	for (i = 0; i < 3; i++) {
670 		/* RED = 0, GREEN = 1, BLUE = 2 */
671 		led[i] = &data->blinkm_leds[i];
672 		led[i]->i2c_client = client;
673 		led[i]->id = i;
674 		led[i]->led_cdev.max_brightness = 255;
675 		led[i]->led_cdev.flags = LED_CORE_SUSPENDRESUME;
676 		atomic_set(&led[i]->active, 0);
677 		switch (i) {
678 		case RED:
679 			snprintf(blinkm_led_name, sizeof(blinkm_led_name),
680 					 "blinkm-%d-%d-red",
681 					 client->adapter->nr,
682 					 client->addr);
683 			led[i]->led_cdev.name = blinkm_led_name;
684 			led[i]->led_cdev.brightness_set = blinkm_led_red_set;
685 			err = led_classdev_register(&client->dev,
686 						    &led[i]->led_cdev);
687 			if (err < 0) {
688 				dev_err(&client->dev,
689 					"couldn't register LED %s\n",
690 					led[i]->led_cdev.name);
691 				goto failred;
692 			}
693 			break;
694 		case GREEN:
695 			snprintf(blinkm_led_name, sizeof(blinkm_led_name),
696 					 "blinkm-%d-%d-green",
697 					 client->adapter->nr,
698 					 client->addr);
699 			led[i]->led_cdev.name = blinkm_led_name;
700 			led[i]->led_cdev.brightness_set = blinkm_led_green_set;
701 			err = led_classdev_register(&client->dev,
702 						    &led[i]->led_cdev);
703 			if (err < 0) {
704 				dev_err(&client->dev,
705 					"couldn't register LED %s\n",
706 					led[i]->led_cdev.name);
707 				goto failgreen;
708 			}
709 			break;
710 		case BLUE:
711 			snprintf(blinkm_led_name, sizeof(blinkm_led_name),
712 					 "blinkm-%d-%d-blue",
713 					 client->adapter->nr,
714 					 client->addr);
715 			led[i]->led_cdev.name = blinkm_led_name;
716 			led[i]->led_cdev.brightness_set = blinkm_led_blue_set;
717 			err = led_classdev_register(&client->dev,
718 						    &led[i]->led_cdev);
719 			if (err < 0) {
720 				dev_err(&client->dev,
721 					"couldn't register LED %s\n",
722 					led[i]->led_cdev.name);
723 				goto failblue;
724 			}
725 			break;
726 		}		/* end switch */
727 	}			/* end for */
728 
729 	/* Initialize the blinkm */
730 	blinkm_init_hw(client);
731 
732 	return 0;
733 
734 failblue:
735 	led_classdev_unregister(&led[GREEN]->led_cdev);
736 
737 failgreen:
738 	led_classdev_unregister(&led[RED]->led_cdev);
739 
740 failred:
741 	sysfs_remove_group(&client->dev.kobj, &blinkm_group);
742 exit:
743 	return err;
744 }
745 
746 static int blinkm_remove(struct i2c_client *client)
747 {
748 	struct blinkm_data *data = i2c_get_clientdata(client);
749 	int ret = 0;
750 	int i;
751 
752 	/* make sure no workqueue entries are pending */
753 	for (i = 0; i < 3; i++) {
754 		flush_scheduled_work();
755 		led_classdev_unregister(&data->blinkm_leds[i].led_cdev);
756 	}
757 
758 	/* reset rgb */
759 	data->next_red = 0x00;
760 	data->next_green = 0x00;
761 	data->next_blue = 0x00;
762 	ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
763 	if (ret < 0)
764 		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
765 
766 	/* reset hsb */
767 	data->next_hue = 0x00;
768 	data->next_saturation = 0x00;
769 	data->next_brightness = 0x00;
770 	ret = blinkm_transfer_hw(client, BLM_FADE_HSB);
771 	if (ret < 0)
772 		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
773 
774 	/* red fade to off */
775 	data->next_red = 0xff;
776 	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
777 	if (ret < 0)
778 		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
779 
780 	/* off */
781 	data->next_red = 0x00;
782 	ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
783 	if (ret < 0)
784 		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
785 
786 	sysfs_remove_group(&client->dev.kobj, &blinkm_group);
787 	return 0;
788 }
789 
790 static const struct i2c_device_id blinkm_id[] = {
791 	{"blinkm", 0},
792 	{}
793 };
794 
795 MODULE_DEVICE_TABLE(i2c, blinkm_id);
796 
797   /* This is the driver that will be inserted */
798 static struct i2c_driver blinkm_driver = {
799 	.class = I2C_CLASS_HWMON,
800 	.driver = {
801 		   .name = "blinkm",
802 		   },
803 	.probe = blinkm_probe,
804 	.remove = blinkm_remove,
805 	.id_table = blinkm_id,
806 	.detect = blinkm_detect,
807 	.address_list = normal_i2c,
808 };
809 
810 module_i2c_driver(blinkm_driver);
811 
812 MODULE_AUTHOR("Jan-Simon Moeller <dl9pf@gmx.de>");
813 MODULE_DESCRIPTION("BlinkM RGB LED driver");
814 MODULE_LICENSE("GPL");
815 
816