3 * (c) Jan-Simon Möller (dl9pf@gmx.de)
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.
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.
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.
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>
32 /* Addresses to scan - BlinkM is on 0x09 by default*/
33 static const unsigned short normal_i2c[] = { 0x09, I2C_CLIENT_END };
35 static int blinkm_transfer_hw(struct i2c_client *client, int cmd);
36 static int blinkm_test_run(struct i2c_client *client);
39 struct i2c_client *i2c_client;
40 struct led_classdev led_cdev;
46 struct blinkm_led *blinkm_led;
47 struct work_struct work;
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)
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 */
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 */
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 */
92 /* mapping command names to cmd chars - see datasheet */
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
112 * as extracted out of the datasheet:
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)
121 static const struct {
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},
148 static ssize_t show_color_common(struct device *dev, char *buf, int color)
150 struct i2c_client *client;
151 struct blinkm_data *data;
154 client = to_i2c_client(dev);
155 data = i2c_get_clientdata(client);
157 ret = blinkm_transfer_hw(client, BLM_GET_CUR_RGB);
162 return scnprintf(buf, PAGE_SIZE, "%02X\n", data->red);
164 return scnprintf(buf, PAGE_SIZE, "%02X\n", data->green);
166 return scnprintf(buf, PAGE_SIZE, "%02X\n", data->blue);
173 static int store_color_common(struct device *dev, const char *buf, int color)
175 struct i2c_client *client;
176 struct blinkm_data *data;
180 client = to_i2c_client(dev);
181 data = i2c_get_clientdata(client);
183 ret = kstrtou8(buf, 10, &value);
185 dev_err(dev, "BlinkM: value too large!\n");
191 data->next_red = value;
194 data->next_green = value;
197 data->next_blue = value;
203 dev_dbg(dev, "next_red = %d, next_green = %d, next_blue = %d\n",
204 data->next_red, data->next_green, data->next_blue);
207 ret = blinkm_transfer_hw(client, BLM_GO_RGB);
209 dev_err(dev, "BlinkM: can't set RGB\n");
215 static ssize_t show_red(struct device *dev, struct device_attribute *attr,
218 return show_color_common(dev, buf, RED);
221 static ssize_t store_red(struct device *dev, struct device_attribute *attr,
222 const char *buf, size_t count)
226 ret = store_color_common(dev, buf, RED);
232 static DEVICE_ATTR(red, S_IRUGO | S_IWUSR, show_red, store_red);
234 static ssize_t show_green(struct device *dev, struct device_attribute *attr,
237 return show_color_common(dev, buf, GREEN);
240 static ssize_t store_green(struct device *dev, struct device_attribute *attr,
241 const char *buf, size_t count)
246 ret = store_color_common(dev, buf, GREEN);
252 static DEVICE_ATTR(green, S_IRUGO | S_IWUSR, show_green, store_green);
254 static ssize_t show_blue(struct device *dev, struct device_attribute *attr,
257 return show_color_common(dev, buf, BLUE);
260 static ssize_t store_blue(struct device *dev, struct device_attribute *attr,
261 const char *buf, size_t count)
265 ret = store_color_common(dev, buf, BLUE);
271 static DEVICE_ATTR(blue, S_IRUGO | S_IWUSR, show_blue, store_blue);
273 static ssize_t show_test(struct device *dev, struct device_attribute *attr,
276 return scnprintf(buf, PAGE_SIZE,
277 "#Write into test to start test sequence!#\n");
280 static ssize_t store_test(struct device *dev, struct device_attribute *attr,
281 const char *buf, size_t count)
284 struct i2c_client *client;
286 client = to_i2c_client(dev);
289 ret = blinkm_test_run(client);
296 static DEVICE_ATTR(test, S_IRUGO | S_IWUSR, show_test, store_test);
298 /* TODO: HSB, fade, timeadj, script ... */
300 static struct attribute *blinkm_attrs[] = {
302 &dev_attr_green.attr,
308 static struct attribute_group blinkm_group = {
310 .attrs = blinkm_attrs,
313 static int blinkm_write(struct i2c_client *client, int cmd, u8 *arg)
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);
322 /* no args to write out */
326 for (i = 0; i < arglen; i++) {
327 /* repeat for arglen */
328 result = i2c_smbus_write_byte(client, arg[i]);
335 static int blinkm_read(struct i2c_client *client, int cmd, u8 *arg)
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);
351 static int blinkm_transfer_hw(struct i2c_client *client, int cmd)
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)
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.
364 /* args / return are in private data struct */
365 struct blinkm_data *data = i2c_get_clientdata(client);
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)
372 /* switch cmd - usually write before reads */
374 case BLM_FADE_RAND_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];
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;
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);
401 case BLM_STOP_SCRIPT:
402 blinkm_write(client, cmd, NULL);
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];
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];
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:
427 case BLM_SET_STARTUP_PARAM:
428 dev_err(&client->dev,
429 "BlinkM: cmd %d not implemented yet.\n", cmd);
432 dev_err(&client->dev, "BlinkM: unknown command %d\n", cmd);
433 mutex_unlock(&data->update_lock);
435 } /* end switch(cmd) */
437 /* transfers done, unlock */
438 mutex_unlock(&data->update_lock);
442 static void led_work(struct work_struct *work)
445 struct blinkm_led *led;
446 struct blinkm_data *data;
447 struct blinkm_work *blm_work = work_to_blmwork(work);
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));
461 static int blinkm_led_common_set(struct led_classdev *led_cdev,
462 enum led_brightness value, int color)
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;
471 /* bail out if there's no change */
472 if (data->next_red == (u8) value)
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)
481 data->next_red = (u8) value;
484 /* bail out if there's no change */
485 if (data->next_green == (u8) value)
487 /* we assume a quite fast sequence here ([off]->on->off)
488 * Revisit: fast-changing brightness. */
489 if (atomic_read(&led->active) > 1)
491 data->next_green = (u8) value;
494 /* bail out if there's no change */
495 if (data->next_blue == (u8) value)
497 /* we assume a quite fast sequence here ([off]->on->off)
498 * Revisit: fast-changing brightness. */
499 if (atomic_read(&led->active) > 1)
501 data->next_blue = (u8) value;
505 dev_err(&led->i2c_client->dev, "BlinkM: unknown color.\n");
509 bl_work = kzalloc(sizeof(*bl_work), GFP_ATOMIC);
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));
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);
529 static void blinkm_led_red_set(struct led_classdev *led_cdev,
530 enum led_brightness value)
532 blinkm_led_common_set(led_cdev, value, RED);
535 static void blinkm_led_green_set(struct led_classdev *led_cdev,
536 enum led_brightness value)
538 blinkm_led_common_set(led_cdev, value, GREEN);
541 static void blinkm_led_blue_set(struct led_classdev *led_cdev,
542 enum led_brightness value)
544 blinkm_led_common_set(led_cdev, value, BLUE);
547 static void blinkm_init_hw(struct i2c_client *client)
550 ret = blinkm_transfer_hw(client, BLM_STOP_SCRIPT);
551 ret = blinkm_transfer_hw(client, BLM_GO_RGB);
554 static int blinkm_test_run(struct i2c_client *client)
557 struct blinkm_data *data = i2c_get_clientdata(client);
559 data->next_red = 0x01;
560 data->next_green = 0x05;
561 data->next_blue = 0x10;
562 ret = blinkm_transfer_hw(client, BLM_GO_RGB);
567 data->next_red = 0x25;
568 data->next_green = 0x10;
569 data->next_blue = 0x31;
570 ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
575 data->next_hue = 0x50;
576 data->next_saturation = 0x10;
577 data->next_brightness = 0x20;
578 ret = blinkm_transfer_hw(client, BLM_FADE_HSB);
586 /* Return 0 if detection is successful, -ENODEV otherwise */
587 static int blinkm_detect(struct i2c_client *client, struct i2c_board_info *info)
589 struct i2c_adapter *adapter = client->adapter;
594 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
595 | I2C_FUNC_SMBUS_WORD_DATA
596 | I2C_FUNC_SMBUS_WRITE_BYTE))
599 /* Now, we do the remaining detection. Simple for now. */
600 /* We might need more guards to protect other i2c slaves */
602 /* make sure the blinkM is balanced (read/writes) */
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)
613 /* Step 1: Read BlinkM address back - cmd_char 'a' */
614 ret = blinkm_write(client, BLM_GET_ADDR, NULL);
617 usleep_range(20000, 30000); /* allow a small delay */
618 ret = blinkm_read(client, BLM_GET_ADDR, tmpargs);
622 if (tmpargs[0] != 0x09) {
623 dev_err(&client->dev, "enodev DEV ADDR = 0x%02X\n", tmpargs[0]);
627 strlcpy(info->type, "blinkm", I2C_NAME_SIZE);
631 static int blinkm_probe(struct i2c_client *client,
632 const struct i2c_device_id *id)
634 struct blinkm_data *data;
635 struct blinkm_led *led[3];
637 char blinkm_led_name[28];
639 data = devm_kzalloc(&client->dev,
640 sizeof(struct blinkm_data), GFP_KERNEL);
646 data->i2c_addr = 0x09;
647 data->i2c_addr = 0x08;
648 /* i2c addr - use fake addr of 0x08 initially (real is 0x09) */
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;
655 i2c_set_clientdata(client, data);
656 mutex_init(&data->update_lock);
658 /* Register sysfs hooks */
659 err = sysfs_create_group(&client->dev.kobj, &blinkm_group);
661 dev_err(&client->dev, "couldn't register sysfs group\n");
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;
670 led[i]->led_cdev.max_brightness = 255;
671 led[i]->led_cdev.flags = LED_CORE_SUSPENDRESUME;
672 atomic_set(&led[i]->active, 0);
675 snprintf(blinkm_led_name, sizeof(blinkm_led_name),
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,
684 dev_err(&client->dev,
685 "couldn't register LED %s\n",
686 led[i]->led_cdev.name);
691 snprintf(blinkm_led_name, sizeof(blinkm_led_name),
692 "blinkm-%d-%d-green",
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,
700 dev_err(&client->dev,
701 "couldn't register LED %s\n",
702 led[i]->led_cdev.name);
707 snprintf(blinkm_led_name, sizeof(blinkm_led_name),
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,
716 dev_err(&client->dev,
717 "couldn't register LED %s\n",
718 led[i]->led_cdev.name);
725 /* Initialize the blinkm */
726 blinkm_init_hw(client);
731 led_classdev_unregister(&led[GREEN]->led_cdev);
734 led_classdev_unregister(&led[RED]->led_cdev);
737 sysfs_remove_group(&client->dev.kobj, &blinkm_group);
742 static int blinkm_remove(struct i2c_client *client)
744 struct blinkm_data *data = i2c_get_clientdata(client);
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);
755 data->next_red = 0x00;
756 data->next_green = 0x00;
757 data->next_blue = 0x00;
758 ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
760 dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
763 data->next_hue = 0x00;
764 data->next_saturation = 0x00;
765 data->next_brightness = 0x00;
766 ret = blinkm_transfer_hw(client, BLM_FADE_HSB);
768 dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
770 /* red fade to off */
771 data->next_red = 0xff;
772 ret = blinkm_transfer_hw(client, BLM_GO_RGB);
774 dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
777 data->next_red = 0x00;
778 ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
780 dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
782 sysfs_remove_group(&client->dev.kobj, &blinkm_group);
786 static const struct i2c_device_id blinkm_id[] = {
791 MODULE_DEVICE_TABLE(i2c, blinkm_id);
793 /* This is the driver that will be inserted */
794 static struct i2c_driver blinkm_driver = {
795 .class = I2C_CLASS_HWMON,
799 .probe = blinkm_probe,
800 .remove = blinkm_remove,
801 .id_table = blinkm_id,
802 .detect = blinkm_detect,
803 .address_list = normal_i2c,
806 module_i2c_driver(blinkm_driver);
808 MODULE_AUTHOR("Jan-Simon Moeller <dl9pf@gmx.de>");
809 MODULE_DESCRIPTION("BlinkM RGB LED driver");
810 MODULE_LICENSE("GPL");