1 /*
2 * Copyright 2011 bct electronic GmbH
3 * Copyright 2013 Qtechnology/AS
4 *
5 * Author: Peter Meerwald <p.meerwald@bct-electronic.com>
6 * Author: Ricardo Ribalda <ricardo.ribalda@gmail.com>
7 *
8 * Based on leds-pca955x.c
9 *
10 * This file is subject to the terms and conditions of version 2 of
11 * the GNU General Public License. See the file COPYING in the main
12 * directory of this archive for more details.
13 *
14 * LED driver for the PCA9633 I2C LED driver (7-bit slave address 0x62)
15 * LED driver for the PCA9634/5 I2C LED driver (7-bit slave address set by hw.)
16 *
17 * Note that hardware blinking violates the leds infrastructure driver
18 * interface since the hardware only supports blinking all LEDs with the
19 * same delay_on/delay_off rates. That is, only the LEDs that are set to
20 * blink will actually blink but all LEDs that are set to blink will blink
21 * in identical fashion. The delay_on/delay_off values of the last LED
22 * that is set to blink will be used for all of the blinking LEDs.
23 * Hardware blinking is disabled by default but can be enabled by setting
24 * the 'blink_type' member in the platform_data struct to 'PCA963X_HW_BLINK'
25 * or by adding the 'nxp,hw-blink' property to the DTS.
26 */
27
28 #include <linux/acpi.h>
29 #include <linux/module.h>
30 #include <linux/delay.h>
31 #include <linux/string.h>
32 #include <linux/ctype.h>
33 #include <linux/leds.h>
34 #include <linux/err.h>
35 #include <linux/i2c.h>
36 #include <linux/slab.h>
37 #include <linux/of.h>
38 #include <linux/platform_data/leds-pca963x.h>
39
40 /* LED select registers determine the source that drives LED outputs */
41 #define PCA963X_LED_OFF 0x0 /* LED driver off */
42 #define PCA963X_LED_ON 0x1 /* LED driver on */
43 #define PCA963X_LED_PWM 0x2 /* Controlled through PWM */
44 #define PCA963X_LED_GRP_PWM 0x3 /* Controlled through PWM/GRPPWM */
45
46 #define PCA963X_MODE2_OUTDRV 0x04 /* Open-drain or totem pole */
47 #define PCA963X_MODE2_INVRT 0x10 /* Normal or inverted direction */
48 #define PCA963X_MODE2_DMBLNK 0x20 /* Enable blinking */
49
50 #define PCA963X_MODE1 0x00
51 #define PCA963X_MODE2 0x01
52 #define PCA963X_PWM_BASE 0x02
53
54 enum pca963x_type {
55 pca9633,
56 pca9634,
57 pca9635,
58 };
59
60 struct pca963x_chipdef {
61 u8 grppwm;
62 u8 grpfreq;
63 u8 ledout_base;
64 int n_leds;
65 unsigned int scaling;
66 };
67
68 static struct pca963x_chipdef pca963x_chipdefs[] = {
69 [pca9633] = {
70 .grppwm = 0x6,
71 .grpfreq = 0x7,
72 .ledout_base = 0x8,
73 .n_leds = 4,
74 },
75 [pca9634] = {
76 .grppwm = 0xa,
77 .grpfreq = 0xb,
78 .ledout_base = 0xc,
79 .n_leds = 8,
80 },
81 [pca9635] = {
82 .grppwm = 0x12,
83 .grpfreq = 0x13,
84 .ledout_base = 0x14,
85 .n_leds = 16,
86 },
87 };
88
89 /* Total blink period in milliseconds */
90 #define PCA963X_BLINK_PERIOD_MIN 42
91 #define PCA963X_BLINK_PERIOD_MAX 10667
92
93 static const struct i2c_device_id pca963x_id[] = {
94 { "pca9632", pca9633 },
95 { "pca9633", pca9633 },
96 { "pca9634", pca9634 },
97 { "pca9635", pca9635 },
98 { }
99 };
100 MODULE_DEVICE_TABLE(i2c, pca963x_id);
101
102 static const struct acpi_device_id pca963x_acpi_ids[] = {
103 { "PCA9632", pca9633 },
104 { "PCA9633", pca9633 },
105 { "PCA9634", pca9634 },
106 { "PCA9635", pca9635 },
107 { }
108 };
109 MODULE_DEVICE_TABLE(acpi, pca963x_acpi_ids);
110
111 struct pca963x_led;
112
113 struct pca963x {
114 struct pca963x_chipdef *chipdef;
115 struct mutex mutex;
116 struct i2c_client *client;
117 struct pca963x_led *leds;
118 unsigned long leds_on;
119 };
120
121 struct pca963x_led {
122 struct pca963x *chip;
123 struct led_classdev led_cdev;
124 int led_num; /* 0 .. 15 potentially */
125 char name[32];
126 u8 gdc;
127 u8 gfrq;
128 };
129
pca963x_brightness(struct pca963x_led * pca963x,enum led_brightness brightness)130 static int pca963x_brightness(struct pca963x_led *pca963x,
131 enum led_brightness brightness)
132 {
133 u8 ledout_addr = pca963x->chip->chipdef->ledout_base
134 + (pca963x->led_num / 4);
135 u8 ledout;
136 int shift = 2 * (pca963x->led_num % 4);
137 u8 mask = 0x3 << shift;
138 int ret;
139
140 ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr);
141 switch (brightness) {
142 case LED_FULL:
143 ret = i2c_smbus_write_byte_data(pca963x->chip->client,
144 ledout_addr,
145 (ledout & ~mask) | (PCA963X_LED_ON << shift));
146 break;
147 case LED_OFF:
148 ret = i2c_smbus_write_byte_data(pca963x->chip->client,
149 ledout_addr, ledout & ~mask);
150 break;
151 default:
152 ret = i2c_smbus_write_byte_data(pca963x->chip->client,
153 PCA963X_PWM_BASE + pca963x->led_num,
154 brightness);
155 if (ret < 0)
156 return ret;
157 ret = i2c_smbus_write_byte_data(pca963x->chip->client,
158 ledout_addr,
159 (ledout & ~mask) | (PCA963X_LED_PWM << shift));
160 break;
161 }
162
163 return ret;
164 }
165
pca963x_blink(struct pca963x_led * pca963x)166 static void pca963x_blink(struct pca963x_led *pca963x)
167 {
168 u8 ledout_addr = pca963x->chip->chipdef->ledout_base +
169 (pca963x->led_num / 4);
170 u8 ledout;
171 u8 mode2 = i2c_smbus_read_byte_data(pca963x->chip->client,
172 PCA963X_MODE2);
173 int shift = 2 * (pca963x->led_num % 4);
174 u8 mask = 0x3 << shift;
175
176 i2c_smbus_write_byte_data(pca963x->chip->client,
177 pca963x->chip->chipdef->grppwm, pca963x->gdc);
178
179 i2c_smbus_write_byte_data(pca963x->chip->client,
180 pca963x->chip->chipdef->grpfreq, pca963x->gfrq);
181
182 if (!(mode2 & PCA963X_MODE2_DMBLNK))
183 i2c_smbus_write_byte_data(pca963x->chip->client, PCA963X_MODE2,
184 mode2 | PCA963X_MODE2_DMBLNK);
185
186 mutex_lock(&pca963x->chip->mutex);
187 ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr);
188 if ((ledout & mask) != (PCA963X_LED_GRP_PWM << shift))
189 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr,
190 (ledout & ~mask) | (PCA963X_LED_GRP_PWM << shift));
191 mutex_unlock(&pca963x->chip->mutex);
192 }
193
pca963x_power_state(struct pca963x_led * pca963x)194 static int pca963x_power_state(struct pca963x_led *pca963x)
195 {
196 unsigned long *leds_on = &pca963x->chip->leds_on;
197 unsigned long cached_leds = pca963x->chip->leds_on;
198
199 if (pca963x->led_cdev.brightness)
200 set_bit(pca963x->led_num, leds_on);
201 else
202 clear_bit(pca963x->led_num, leds_on);
203
204 if (!(*leds_on) != !cached_leds)
205 return i2c_smbus_write_byte_data(pca963x->chip->client,
206 PCA963X_MODE1, *leds_on ? 0 : BIT(4));
207
208 return 0;
209 }
210
pca963x_led_set(struct led_classdev * led_cdev,enum led_brightness value)211 static int pca963x_led_set(struct led_classdev *led_cdev,
212 enum led_brightness value)
213 {
214 struct pca963x_led *pca963x;
215 int ret;
216
217 pca963x = container_of(led_cdev, struct pca963x_led, led_cdev);
218
219 mutex_lock(&pca963x->chip->mutex);
220
221 ret = pca963x_brightness(pca963x, value);
222 if (ret < 0)
223 goto unlock;
224 ret = pca963x_power_state(pca963x);
225
226 unlock:
227 mutex_unlock(&pca963x->chip->mutex);
228 return ret;
229 }
230
pca963x_period_scale(struct pca963x_led * pca963x,unsigned int val)231 static unsigned int pca963x_period_scale(struct pca963x_led *pca963x,
232 unsigned int val)
233 {
234 unsigned int scaling = pca963x->chip->chipdef->scaling;
235
236 return scaling ? DIV_ROUND_CLOSEST(val * scaling, 1000) : val;
237 }
238
pca963x_blink_set(struct led_classdev * led_cdev,unsigned long * delay_on,unsigned long * delay_off)239 static int pca963x_blink_set(struct led_classdev *led_cdev,
240 unsigned long *delay_on, unsigned long *delay_off)
241 {
242 struct pca963x_led *pca963x;
243 unsigned long time_on, time_off, period;
244 u8 gdc, gfrq;
245
246 pca963x = container_of(led_cdev, struct pca963x_led, led_cdev);
247
248 time_on = *delay_on;
249 time_off = *delay_off;
250
251 /* If both zero, pick reasonable defaults of 500ms each */
252 if (!time_on && !time_off) {
253 time_on = 500;
254 time_off = 500;
255 }
256
257 period = pca963x_period_scale(pca963x, time_on + time_off);
258
259 /* If period not supported by hardware, default to someting sane. */
260 if ((period < PCA963X_BLINK_PERIOD_MIN) ||
261 (period > PCA963X_BLINK_PERIOD_MAX)) {
262 time_on = 500;
263 time_off = 500;
264 period = pca963x_period_scale(pca963x, 1000);
265 }
266
267 /*
268 * From manual: duty cycle = (GDC / 256) ->
269 * (time_on / period) = (GDC / 256) ->
270 * GDC = ((time_on * 256) / period)
271 */
272 gdc = (pca963x_period_scale(pca963x, time_on) * 256) / period;
273
274 /*
275 * From manual: period = ((GFRQ + 1) / 24) in seconds.
276 * So, period (in ms) = (((GFRQ + 1) / 24) * 1000) ->
277 * GFRQ = ((period * 24 / 1000) - 1)
278 */
279 gfrq = (period * 24 / 1000) - 1;
280
281 pca963x->gdc = gdc;
282 pca963x->gfrq = gfrq;
283
284 pca963x_blink(pca963x);
285
286 *delay_on = time_on;
287 *delay_off = time_off;
288
289 return 0;
290 }
291
292 #if IS_ENABLED(CONFIG_OF)
293 static struct pca963x_platform_data *
pca963x_dt_init(struct i2c_client * client,struct pca963x_chipdef * chip)294 pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip)
295 {
296 struct device_node *np = client->dev.of_node, *child;
297 struct pca963x_platform_data *pdata;
298 struct led_info *pca963x_leds;
299 int count;
300
301 count = of_get_child_count(np);
302 if (!count || count > chip->n_leds)
303 return ERR_PTR(-ENODEV);
304
305 pca963x_leds = devm_kzalloc(&client->dev,
306 sizeof(struct led_info) * chip->n_leds, GFP_KERNEL);
307 if (!pca963x_leds)
308 return ERR_PTR(-ENOMEM);
309
310 for_each_child_of_node(np, child) {
311 struct led_info led = {};
312 u32 reg;
313 int res;
314
315 res = of_property_read_u32(child, "reg", ®);
316 if ((res != 0) || (reg >= chip->n_leds))
317 continue;
318 led.name =
319 of_get_property(child, "label", NULL) ? : child->name;
320 led.default_trigger =
321 of_get_property(child, "linux,default-trigger", NULL);
322 pca963x_leds[reg] = led;
323 }
324 pdata = devm_kzalloc(&client->dev,
325 sizeof(struct pca963x_platform_data), GFP_KERNEL);
326 if (!pdata)
327 return ERR_PTR(-ENOMEM);
328
329 pdata->leds.leds = pca963x_leds;
330 pdata->leds.num_leds = chip->n_leds;
331
332 /* default to open-drain unless totem pole (push-pull) is specified */
333 if (of_property_read_bool(np, "nxp,totem-pole"))
334 pdata->outdrv = PCA963X_TOTEM_POLE;
335 else
336 pdata->outdrv = PCA963X_OPEN_DRAIN;
337
338 /* default to software blinking unless hardware blinking is specified */
339 if (of_property_read_bool(np, "nxp,hw-blink"))
340 pdata->blink_type = PCA963X_HW_BLINK;
341 else
342 pdata->blink_type = PCA963X_SW_BLINK;
343
344 if (of_property_read_u32(np, "nxp,period-scale", &chip->scaling))
345 chip->scaling = 1000;
346
347 /* default to non-inverted output, unless inverted is specified */
348 if (of_property_read_bool(np, "nxp,inverted-out"))
349 pdata->dir = PCA963X_INVERTED;
350 else
351 pdata->dir = PCA963X_NORMAL;
352
353 return pdata;
354 }
355
356 static const struct of_device_id of_pca963x_match[] = {
357 { .compatible = "nxp,pca9632", },
358 { .compatible = "nxp,pca9633", },
359 { .compatible = "nxp,pca9634", },
360 { .compatible = "nxp,pca9635", },
361 {},
362 };
363 MODULE_DEVICE_TABLE(of, of_pca963x_match);
364 #else
365 static struct pca963x_platform_data *
pca963x_dt_init(struct i2c_client * client,struct pca963x_chipdef * chip)366 pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip)
367 {
368 return ERR_PTR(-ENODEV);
369 }
370 #endif
371
pca963x_probe(struct i2c_client * client,const struct i2c_device_id * id)372 static int pca963x_probe(struct i2c_client *client,
373 const struct i2c_device_id *id)
374 {
375 struct pca963x *pca963x_chip;
376 struct pca963x_led *pca963x;
377 struct pca963x_platform_data *pdata;
378 struct pca963x_chipdef *chip;
379 int i, err;
380
381 if (id) {
382 chip = &pca963x_chipdefs[id->driver_data];
383 } else {
384 const struct acpi_device_id *acpi_id;
385
386 acpi_id = acpi_match_device(pca963x_acpi_ids, &client->dev);
387 if (!acpi_id)
388 return -ENODEV;
389 chip = &pca963x_chipdefs[acpi_id->driver_data];
390 }
391 pdata = dev_get_platdata(&client->dev);
392
393 if (!pdata) {
394 pdata = pca963x_dt_init(client, chip);
395 if (IS_ERR(pdata)) {
396 dev_warn(&client->dev, "could not parse configuration\n");
397 pdata = NULL;
398 }
399 }
400
401 if (pdata && (pdata->leds.num_leds < 1 ||
402 pdata->leds.num_leds > chip->n_leds)) {
403 dev_err(&client->dev, "board info must claim 1-%d LEDs",
404 chip->n_leds);
405 return -EINVAL;
406 }
407
408 pca963x_chip = devm_kzalloc(&client->dev, sizeof(*pca963x_chip),
409 GFP_KERNEL);
410 if (!pca963x_chip)
411 return -ENOMEM;
412 pca963x = devm_kzalloc(&client->dev, chip->n_leds * sizeof(*pca963x),
413 GFP_KERNEL);
414 if (!pca963x)
415 return -ENOMEM;
416
417 i2c_set_clientdata(client, pca963x_chip);
418
419 mutex_init(&pca963x_chip->mutex);
420 pca963x_chip->chipdef = chip;
421 pca963x_chip->client = client;
422 pca963x_chip->leds = pca963x;
423
424 /* Turn off LEDs by default*/
425 for (i = 0; i < chip->n_leds / 4; i++)
426 i2c_smbus_write_byte_data(client, chip->ledout_base + i, 0x00);
427
428 for (i = 0; i < chip->n_leds; i++) {
429 pca963x[i].led_num = i;
430 pca963x[i].chip = pca963x_chip;
431
432 /* Platform data can specify LED names and default triggers */
433 if (pdata && i < pdata->leds.num_leds) {
434 if (pdata->leds.leds[i].name)
435 snprintf(pca963x[i].name,
436 sizeof(pca963x[i].name), "pca963x:%s",
437 pdata->leds.leds[i].name);
438 if (pdata->leds.leds[i].default_trigger)
439 pca963x[i].led_cdev.default_trigger =
440 pdata->leds.leds[i].default_trigger;
441 }
442 if (!pdata || i >= pdata->leds.num_leds ||
443 !pdata->leds.leds[i].name)
444 snprintf(pca963x[i].name, sizeof(pca963x[i].name),
445 "pca963x:%d:%.2x:%d", client->adapter->nr,
446 client->addr, i);
447
448 pca963x[i].led_cdev.name = pca963x[i].name;
449 pca963x[i].led_cdev.brightness_set_blocking = pca963x_led_set;
450
451 if (pdata && pdata->blink_type == PCA963X_HW_BLINK)
452 pca963x[i].led_cdev.blink_set = pca963x_blink_set;
453
454 err = led_classdev_register(&client->dev, &pca963x[i].led_cdev);
455 if (err < 0)
456 goto exit;
457 }
458
459 /* Disable LED all-call address, and power down initially */
460 i2c_smbus_write_byte_data(client, PCA963X_MODE1, BIT(4));
461
462 if (pdata) {
463 u8 mode2 = i2c_smbus_read_byte_data(pca963x->chip->client,
464 PCA963X_MODE2);
465 /* Configure output: open-drain or totem pole (push-pull) */
466 if (pdata->outdrv == PCA963X_OPEN_DRAIN)
467 mode2 &= ~PCA963X_MODE2_OUTDRV;
468 else
469 mode2 |= PCA963X_MODE2_OUTDRV;
470 /* Configure direction: normal or inverted */
471 if (pdata->dir == PCA963X_INVERTED)
472 mode2 |= PCA963X_MODE2_INVRT;
473 i2c_smbus_write_byte_data(pca963x->chip->client, PCA963X_MODE2,
474 mode2);
475 }
476
477 return 0;
478
479 exit:
480 while (i--)
481 led_classdev_unregister(&pca963x[i].led_cdev);
482
483 return err;
484 }
485
pca963x_remove(struct i2c_client * client)486 static int pca963x_remove(struct i2c_client *client)
487 {
488 struct pca963x *pca963x = i2c_get_clientdata(client);
489 int i;
490
491 for (i = 0; i < pca963x->chipdef->n_leds; i++)
492 led_classdev_unregister(&pca963x->leds[i].led_cdev);
493
494 return 0;
495 }
496
497 static struct i2c_driver pca963x_driver = {
498 .driver = {
499 .name = "leds-pca963x",
500 .of_match_table = of_match_ptr(of_pca963x_match),
501 .acpi_match_table = ACPI_PTR(pca963x_acpi_ids),
502 },
503 .probe = pca963x_probe,
504 .remove = pca963x_remove,
505 .id_table = pca963x_id,
506 };
507
508 module_i2c_driver(pca963x_driver);
509
510 MODULE_AUTHOR("Peter Meerwald <p.meerwald@bct-electronic.com>");
511 MODULE_DESCRIPTION("PCA963X LED driver");
512 MODULE_LICENSE("GPL v2");
513