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x86/speculation/mds: Fix documentation typo
[linux/fpc-iii.git] / drivers / leds / leds-pca963x.c
blob3bf9a127181927d84f374c1b60cc9373dafad149
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_DMBLNK 0x20 /* Enable blinking */
47
48 #define PCA963X_MODE1 0x00
49 #define PCA963X_MODE2 0x01
50 #define PCA963X_PWM_BASE 0x02
51
52 enum pca963x_type {
53 pca9633,
54 pca9634,
55 pca9635,
56 };
57
58 struct pca963x_chipdef {
59 u8 grppwm;
60 u8 grpfreq;
61 u8 ledout_base;
62 int n_leds;
63 unsigned int scaling;
64 };
65
66 static struct pca963x_chipdef pca963x_chipdefs[] = {
67 [pca9633] = {
68 .grppwm = 0x6,
69 .grpfreq = 0x7,
70 .ledout_base = 0x8,
71 .n_leds = 4,
72 },
73 [pca9634] = {
74 .grppwm = 0xa,
75 .grpfreq = 0xb,
76 .ledout_base = 0xc,
77 .n_leds = 8,
78 },
79 [pca9635] = {
80 .grppwm = 0x12,
81 .grpfreq = 0x13,
82 .ledout_base = 0x14,
83 .n_leds = 16,
84 },
85 };
86
87 /* Total blink period in milliseconds */
88 #define PCA963X_BLINK_PERIOD_MIN 42
89 #define PCA963X_BLINK_PERIOD_MAX 10667
90
91 static const struct i2c_device_id pca963x_id[] = {
92 { "pca9632", pca9633 },
93 { "pca9633", pca9633 },
94 { "pca9634", pca9634 },
95 { "pca9635", pca9635 },
96 { }
97 };
98 MODULE_DEVICE_TABLE(i2c, pca963x_id);
99
100 static const struct acpi_device_id pca963x_acpi_ids[] = {
101 { "PCA9632", pca9633 },
102 { "PCA9633", pca9633 },
103 { "PCA9634", pca9634 },
104 { "PCA9635", pca9635 },
105 { }
106 };
107 MODULE_DEVICE_TABLE(acpi, pca963x_acpi_ids);
108
109 struct pca963x_led;
110
111 struct pca963x {
112 struct pca963x_chipdef *chipdef;
113 struct mutex mutex;
114 struct i2c_client *client;
115 struct pca963x_led *leds;
116 unsigned long leds_on;
117 };
118
119 struct pca963x_led {
120 struct pca963x *chip;
121 struct led_classdev led_cdev;
122 int led_num; /* 0 .. 15 potentially */
123 char name[32];
124 u8 gdc;
125 u8 gfrq;
126 };
127
128 static int pca963x_brightness(struct pca963x_led *pca963x,
129 enum led_brightness brightness)
130 {
131 u8 ledout_addr = pca963x->chip->chipdef->ledout_base
132 + (pca963x->led_num / 4);
133 u8 ledout;
134 int shift = 2 * (pca963x->led_num % 4);
135 u8 mask = 0x3 << shift;
136 int ret;
137
138 ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr);
139 switch (brightness) {
140 case LED_FULL:
141 ret = i2c_smbus_write_byte_data(pca963x->chip->client,
142 ledout_addr,
143 (ledout & ~mask) | (PCA963X_LED_ON << shift));
144 break;
145 case LED_OFF:
146 ret = i2c_smbus_write_byte_data(pca963x->chip->client,
147 ledout_addr, ledout & ~mask);
148 break;
149 default:
150 ret = i2c_smbus_write_byte_data(pca963x->chip->client,
151 PCA963X_PWM_BASE + pca963x->led_num,
152 brightness);
153 if (ret < 0)
154 return ret;
155 ret = i2c_smbus_write_byte_data(pca963x->chip->client,
156 ledout_addr,
157 (ledout & ~mask) | (PCA963X_LED_PWM << shift));
158 break;
159 }
160
161 return ret;
162 }
163
164 static void pca963x_blink(struct pca963x_led *pca963x)
165 {
166 u8 ledout_addr = pca963x->chip->chipdef->ledout_base +
167 (pca963x->led_num / 4);
168 u8 ledout;
169 u8 mode2 = i2c_smbus_read_byte_data(pca963x->chip->client,
170 PCA963X_MODE2);
171 int shift = 2 * (pca963x->led_num % 4);
172 u8 mask = 0x3 << shift;
173
174 i2c_smbus_write_byte_data(pca963x->chip->client,
175 pca963x->chip->chipdef->grppwm, pca963x->gdc);
176
177 i2c_smbus_write_byte_data(pca963x->chip->client,
178 pca963x->chip->chipdef->grpfreq, pca963x->gfrq);
179
180 if (!(mode2 & PCA963X_MODE2_DMBLNK))
181 i2c_smbus_write_byte_data(pca963x->chip->client, PCA963X_MODE2,
182 mode2 | PCA963X_MODE2_DMBLNK);
183
184 mutex_lock(&pca963x->chip->mutex);
185 ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr);
186 if ((ledout & mask) != (PCA963X_LED_GRP_PWM << shift))
187 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr,
188 (ledout & ~mask) | (PCA963X_LED_GRP_PWM << shift));
189 mutex_unlock(&pca963x->chip->mutex);
190 }
191
192 static int pca963x_power_state(struct pca963x_led *pca963x)
193 {
194 unsigned long *leds_on = &pca963x->chip->leds_on;
195 unsigned long cached_leds = pca963x->chip->leds_on;
196
197 if (pca963x->led_cdev.brightness)
198 set_bit(pca963x->led_num, leds_on);
199 else
200 clear_bit(pca963x->led_num, leds_on);
201
202 if (!(*leds_on) != !cached_leds)
203 return i2c_smbus_write_byte_data(pca963x->chip->client,
204 PCA963X_MODE1, *leds_on ? 0 : BIT(4));
205
206 return 0;
207 }
208
209 static int pca963x_led_set(struct led_classdev *led_cdev,
210 enum led_brightness value)
211 {
212 struct pca963x_led *pca963x;
213 int ret;
214
215 pca963x = container_of(led_cdev, struct pca963x_led, led_cdev);
216
217 mutex_lock(&pca963x->chip->mutex);
218
219 ret = pca963x_brightness(pca963x, value);
220 if (ret < 0)
221 goto unlock;
222 ret = pca963x_power_state(pca963x);
223
224 unlock:
225 mutex_unlock(&pca963x->chip->mutex);
226 return ret;
227 }
228
229 static unsigned int pca963x_period_scale(struct pca963x_led *pca963x,
230 unsigned int val)
231 {
232 unsigned int scaling = pca963x->chip->chipdef->scaling;
233
234 return scaling ? DIV_ROUND_CLOSEST(val * scaling, 1000) : val;
235 }
236
237 static int pca963x_blink_set(struct led_classdev *led_cdev,
238 unsigned long *delay_on, unsigned long *delay_off)
239 {
240 struct pca963x_led *pca963x;
241 unsigned long time_on, time_off, period;
242 u8 gdc, gfrq;
243
244 pca963x = container_of(led_cdev, struct pca963x_led, led_cdev);
245
246 time_on = *delay_on;
247 time_off = *delay_off;
248
249 /* If both zero, pick reasonable defaults of 500ms each */
250 if (!time_on && !time_off) {
251 time_on = 500;
252 time_off = 500;
253 }
254
255 period = pca963x_period_scale(pca963x, time_on + time_off);
256
257 /* If period not supported by hardware, default to someting sane. */
258 if ((period < PCA963X_BLINK_PERIOD_MIN) ||
259 (period > PCA963X_BLINK_PERIOD_MAX)) {
260 time_on = 500;
261 time_off = 500;
262 period = pca963x_period_scale(pca963x, 1000);
263 }
264
265 /*
266 * From manual: duty cycle = (GDC / 256) ->
267 * (time_on / period) = (GDC / 256) ->
268 * GDC = ((time_on * 256) / period)
269 */
270 gdc = (pca963x_period_scale(pca963x, time_on) * 256) / period;
271
272 /*
273 * From manual: period = ((GFRQ + 1) / 24) in seconds.
274 * So, period (in ms) = (((GFRQ + 1) / 24) * 1000) ->
275 * GFRQ = ((period * 24 / 1000) - 1)
276 */
277 gfrq = (period * 24 / 1000) - 1;
278
279 pca963x->gdc = gdc;
280 pca963x->gfrq = gfrq;
281
282 pca963x_blink(pca963x);
283
284 *delay_on = time_on;
285 *delay_off = time_off;
286
287 return 0;
288 }
289
290 #if IS_ENABLED(CONFIG_OF)
291 static struct pca963x_platform_data *
292 pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip)
293 {
294 struct device_node *np = client->dev.of_node, *child;
295 struct pca963x_platform_data *pdata;
296 struct led_info *pca963x_leds;
297 int count;
298
299 count = of_get_child_count(np);
300 if (!count || count > chip->n_leds)
301 return ERR_PTR(-ENODEV);
302
303 pca963x_leds = devm_kzalloc(&client->dev,
304 sizeof(struct led_info) * chip->n_leds, GFP_KERNEL);
305 if (!pca963x_leds)
306 return ERR_PTR(-ENOMEM);
307
308 for_each_child_of_node(np, child) {
309 struct led_info led = {};
310 u32 reg;
311 int res;
312
313 res = of_property_read_u32(child, "reg", &reg);
314 if ((res != 0) || (reg >= chip->n_leds))
315 continue;
316 led.name =
317 of_get_property(child, "label", NULL) ? : child->name;
318 led.default_trigger =
319 of_get_property(child, "linux,default-trigger", NULL);
320 pca963x_leds[reg] = led;
321 }
322 pdata = devm_kzalloc(&client->dev,
323 sizeof(struct pca963x_platform_data), GFP_KERNEL);
324 if (!pdata)
325 return ERR_PTR(-ENOMEM);
326
327 pdata->leds.leds = pca963x_leds;
328 pdata->leds.num_leds = chip->n_leds;
329
330 /* default to open-drain unless totem pole (push-pull) is specified */
331 if (of_property_read_bool(np, "nxp,totem-pole"))
332 pdata->outdrv = PCA963X_TOTEM_POLE;
333 else
334 pdata->outdrv = PCA963X_OPEN_DRAIN;
335
336 /* default to software blinking unless hardware blinking is specified */
337 if (of_property_read_bool(np, "nxp,hw-blink"))
338 pdata->blink_type = PCA963X_HW_BLINK;
339 else
340 pdata->blink_type = PCA963X_SW_BLINK;
341
342 if (of_property_read_u32(np, "nxp,period-scale", &chip->scaling))
343 chip->scaling = 1000;
344
345 /* default to non-inverted output, unless inverted is specified */
346 if (of_property_read_bool(np, "nxp,inverted-out"))
347 pdata->dir = PCA963X_INVERTED;
348 else
349 pdata->dir = PCA963X_NORMAL;
350
351 return pdata;
352 }
353
354 static const struct of_device_id of_pca963x_match[] = {
355 { .compatible = "nxp,pca9632", },
356 { .compatible = "nxp,pca9633", },
357 { .compatible = "nxp,pca9634", },
358 { .compatible = "nxp,pca9635", },
359 {},
360 };
361 MODULE_DEVICE_TABLE(of, of_pca963x_match);
362 #else
363 static struct pca963x_platform_data *
364 pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip)
365 {
366 return ERR_PTR(-ENODEV);
367 }
368 #endif
369
370 static int pca963x_probe(struct i2c_client *client,
371 const struct i2c_device_id *id)
372 {
373 struct pca963x *pca963x_chip;
374 struct pca963x_led *pca963x;
375 struct pca963x_platform_data *pdata;
376 struct pca963x_chipdef *chip;
377 int i, err;
378
379 if (id) {
380 chip = &pca963x_chipdefs[id->driver_data];
381 } else {
382 const struct acpi_device_id *acpi_id;
383
384 acpi_id = acpi_match_device(pca963x_acpi_ids, &client->dev);
385 if (!acpi_id)
386 return -ENODEV;
387 chip = &pca963x_chipdefs[acpi_id->driver_data];
388 }
389 pdata = dev_get_platdata(&client->dev);
390
391 if (!pdata) {
392 pdata = pca963x_dt_init(client, chip);
393 if (IS_ERR(pdata)) {
394 dev_warn(&client->dev, "could not parse configuration\n");
395 pdata = NULL;
396 }
397 }
398
399 if (pdata && (pdata->leds.num_leds < 1 ||
400 pdata->leds.num_leds > chip->n_leds)) {
401 dev_err(&client->dev, "board info must claim 1-%d LEDs",
402 chip->n_leds);
403 return -EINVAL;
404 }
405
406 pca963x_chip = devm_kzalloc(&client->dev, sizeof(*pca963x_chip),
407 GFP_KERNEL);
408 if (!pca963x_chip)
409 return -ENOMEM;
410 pca963x = devm_kzalloc(&client->dev, chip->n_leds * sizeof(*pca963x),
411 GFP_KERNEL);
412 if (!pca963x)
413 return -ENOMEM;
414
415 i2c_set_clientdata(client, pca963x_chip);
416
417 mutex_init(&pca963x_chip->mutex);
418 pca963x_chip->chipdef = chip;
419 pca963x_chip->client = client;
420 pca963x_chip->leds = pca963x;
421
422 /* Turn off LEDs by default*/
423 for (i = 0; i < chip->n_leds / 4; i++)
424 i2c_smbus_write_byte_data(client, chip->ledout_base + i, 0x00);
425
426 for (i = 0; i < chip->n_leds; i++) {
427 pca963x[i].led_num = i;
428 pca963x[i].chip = pca963x_chip;
429
430 /* Platform data can specify LED names and default triggers */
431 if (pdata && i < pdata->leds.num_leds) {
432 if (pdata->leds.leds[i].name)
433 snprintf(pca963x[i].name,
434 sizeof(pca963x[i].name), "pca963x:%s",
435 pdata->leds.leds[i].name);
436 if (pdata->leds.leds[i].default_trigger)
437 pca963x[i].led_cdev.default_trigger =
438 pdata->leds.leds[i].default_trigger;
439 }
440 if (!pdata || i >= pdata->leds.num_leds ||
441 !pdata->leds.leds[i].name)
442 snprintf(pca963x[i].name, sizeof(pca963x[i].name),
443 "pca963x:%d:%.2x:%d", client->adapter->nr,
444 client->addr, i);
445
446 pca963x[i].led_cdev.name = pca963x[i].name;
447 pca963x[i].led_cdev.brightness_set_blocking = pca963x_led_set;
448
449 if (pdata && pdata->blink_type == PCA963X_HW_BLINK)
450 pca963x[i].led_cdev.blink_set = pca963x_blink_set;
451
452 err = led_classdev_register(&client->dev, &pca963x[i].led_cdev);
453 if (err < 0)
454 goto exit;
455 }
456
457 /* Disable LED all-call address, and power down initially */
458 i2c_smbus_write_byte_data(client, PCA963X_MODE1, BIT(4));
459
460 if (pdata) {
461 u8 mode2 = i2c_smbus_read_byte_data(pca963x->chip->client,
462 PCA963X_MODE2);
463 /* Configure output: open-drain or totem pole (push-pull) */
464 if (pdata->outdrv == PCA963X_OPEN_DRAIN)
465 mode2 |= 0x01;
466 else
467 mode2 |= 0x05;
468 /* Configure direction: normal or inverted */
469 if (pdata->dir == PCA963X_INVERTED)
470 mode2 |= 0x10;
471 i2c_smbus_write_byte_data(pca963x->chip->client, PCA963X_MODE2,
472 mode2);
473 }
474
475 return 0;
476
477 exit:
478 while (i--)
479 led_classdev_unregister(&pca963x[i].led_cdev);
480
481 return err;
482 }
483
484 static int pca963x_remove(struct i2c_client *client)
485 {
486 struct pca963x *pca963x = i2c_get_clientdata(client);
487 int i;
488
489 for (i = 0; i < pca963x->chipdef->n_leds; i++)
490 led_classdev_unregister(&pca963x->leds[i].led_cdev);
491
492 return 0;
493 }
494
495 static struct i2c_driver pca963x_driver = {
496 .driver = {
497 .name = "leds-pca963x",
498 .of_match_table = of_match_ptr(of_pca963x_match),
499 .acpi_match_table = ACPI_PTR(pca963x_acpi_ids),
500 },
501 .probe = pca963x_probe,
502 .remove = pca963x_remove,
503 .id_table = pca963x_id,
504 };
505
506 module_i2c_driver(pca963x_driver);
507
508 MODULE_AUTHOR("Peter Meerwald <p.meerwald@bct-electronic.com>");
509 MODULE_DESCRIPTION("PCA963X LED driver");
510 MODULE_LICENSE("GPL v2");
Linux with added FPC-III support