1 /*
2 * pca9532.c - 16-bit Led dimmer
3 *
4 * Copyright (C) 2011 Jan Weitzel
5 * Copyright (C) 2008 Riku Voipio
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; version 2 of the License.
10 *
11 * Datasheet: http://www.nxp.com/documents/data_sheet/PCA9532.pdf
12 *
13 */
14
15 #include <linux/module.h>
16 #include <linux/i2c.h>
17 #include <linux/slab.h>
18 #include <linux/leds.h>
19 #include <linux/input.h>
20 #include <linux/mutex.h>
21 #include <linux/workqueue.h>
22 #include <linux/leds-pca9532.h>
23 #include <linux/gpio.h>
24
25 /* m = num_leds*/
26 #define PCA9532_REG_INPUT(i) ((i) >> 3)
27 #define PCA9532_REG_OFFSET(m) ((m) >> 4)
28 #define PCA9532_REG_PSC(m, i) (PCA9532_REG_OFFSET(m) + 0x1 + (i) * 2)
29 #define PCA9532_REG_PWM(m, i) (PCA9532_REG_OFFSET(m) + 0x2 + (i) * 2)
30 #define LED_REG(m, led) (PCA9532_REG_OFFSET(m) + 0x5 + (led >> 2))
31 #define LED_NUM(led) (led & 0x3)
32
33 #define ldev_to_led(c) container_of(c, struct pca9532_led, ldev)
34
35 struct pca9532_chip_info {
36 u8 num_leds;
37 };
38
39 struct pca9532_data {
40 struct i2c_client *client;
41 struct pca9532_led leds[16];
42 struct mutex update_lock;
43 struct input_dev *idev;
44 struct work_struct work;
45 #ifdef CONFIG_LEDS_PCA9532_GPIO
46 struct gpio_chip gpio;
47 #endif
48 const struct pca9532_chip_info *chip_info;
49 u8 pwm[2];
50 u8 psc[2];
51 };
52
53 static int pca9532_probe(struct i2c_client *client,
54 const struct i2c_device_id *id);
55 static int pca9532_remove(struct i2c_client *client);
56
57 enum {
58 pca9530,
59 pca9531,
60 pca9532,
61 pca9533,
62 };
63
64 static const struct i2c_device_id pca9532_id[] = {
65 { "pca9530", pca9530 },
66 { "pca9531", pca9531 },
67 { "pca9532", pca9532 },
68 { "pca9533", pca9533 },
69 { }
70 };
71
72 MODULE_DEVICE_TABLE(i2c, pca9532_id);
73
74 static const struct pca9532_chip_info pca9532_chip_info_tbl[] = {
75 [pca9530] = {
76 .num_leds = 2,
77 },
78 [pca9531] = {
79 .num_leds = 8,
80 },
81 [pca9532] = {
82 .num_leds = 16,
83 },
84 [pca9533] = {
85 .num_leds = 4,
86 },
87 };
88
89 static struct i2c_driver pca9532_driver = {
90 .driver = {
91 .name = "leds-pca953x",
92 },
93 .probe = pca9532_probe,
94 .remove = pca9532_remove,
95 .id_table = pca9532_id,
96 };
97
98 /* We have two pwm/blinkers, but 16 possible leds to drive. Additionally,
99 * the clever Thecus people are using one pwm to drive the beeper. So,
100 * as a compromise we average one pwm to the values requested by all
101 * leds that are not ON/OFF.
102 * */
pca9532_calcpwm(struct i2c_client * client,int pwm,int blink,enum led_brightness value)103 static int pca9532_calcpwm(struct i2c_client *client, int pwm, int blink,
104 enum led_brightness value)
105 {
106 int a = 0, b = 0, i = 0;
107 struct pca9532_data *data = i2c_get_clientdata(client);
108 for (i = 0; i < data->chip_info->num_leds; i++) {
109 if (data->leds[i].type == PCA9532_TYPE_LED &&
110 data->leds[i].state == PCA9532_PWM0+pwm) {
111 a++;
112 b += data->leds[i].ldev.brightness;
113 }
114 }
115 if (a == 0) {
116 dev_err(&client->dev,
117 "fear of division by zero %d/%d, wanted %d\n",
118 b, a, value);
119 return -EINVAL;
120 }
121 b = b/a;
122 if (b > 0xFF)
123 return -EINVAL;
124 data->pwm[pwm] = b;
125 data->psc[pwm] = blink;
126 return 0;
127 }
128
pca9532_setpwm(struct i2c_client * client,int pwm)129 static int pca9532_setpwm(struct i2c_client *client, int pwm)
130 {
131 struct pca9532_data *data = i2c_get_clientdata(client);
132 u8 maxleds = data->chip_info->num_leds;
133
134 mutex_lock(&data->update_lock);
135 i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, pwm),
136 data->pwm[pwm]);
137 i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, pwm),
138 data->psc[pwm]);
139 mutex_unlock(&data->update_lock);
140 return 0;
141 }
142
143 /* Set LED routing */
pca9532_setled(struct pca9532_led * led)144 static void pca9532_setled(struct pca9532_led *led)
145 {
146 struct i2c_client *client = led->client;
147 struct pca9532_data *data = i2c_get_clientdata(client);
148 u8 maxleds = data->chip_info->num_leds;
149 char reg;
150
151 mutex_lock(&data->update_lock);
152 reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
153 /* zero led bits */
154 reg = reg & ~(0x3<<LED_NUM(led->id)*2);
155 /* set the new value */
156 reg = reg | (led->state << LED_NUM(led->id)*2);
157 i2c_smbus_write_byte_data(client, LED_REG(maxleds, led->id), reg);
158 mutex_unlock(&data->update_lock);
159 }
160
pca9532_set_brightness(struct led_classdev * led_cdev,enum led_brightness value)161 static void pca9532_set_brightness(struct led_classdev *led_cdev,
162 enum led_brightness value)
163 {
164 int err = 0;
165 struct pca9532_led *led = ldev_to_led(led_cdev);
166
167 if (value == LED_OFF)
168 led->state = PCA9532_OFF;
169 else if (value == LED_FULL)
170 led->state = PCA9532_ON;
171 else {
172 led->state = PCA9532_PWM0; /* Thecus: hardcode one pwm */
173 err = pca9532_calcpwm(led->client, 0, 0, value);
174 if (err)
175 return; /* XXX: led api doesn't allow error code? */
176 }
177 schedule_work(&led->work);
178 }
179
pca9532_set_blink(struct led_classdev * led_cdev,unsigned long * delay_on,unsigned long * delay_off)180 static int pca9532_set_blink(struct led_classdev *led_cdev,
181 unsigned long *delay_on, unsigned long *delay_off)
182 {
183 struct pca9532_led *led = ldev_to_led(led_cdev);
184 struct i2c_client *client = led->client;
185 int psc;
186 int err = 0;
187
188 if (*delay_on == 0 && *delay_off == 0) {
189 /* led subsystem ask us for a blink rate */
190 *delay_on = 1000;
191 *delay_off = 1000;
192 }
193 if (*delay_on != *delay_off || *delay_on > 1690 || *delay_on < 6)
194 return -EINVAL;
195
196 /* Thecus specific: only use PSC/PWM 0 */
197 psc = (*delay_on * 152-1)/1000;
198 err = pca9532_calcpwm(client, 0, psc, led_cdev->brightness);
199 if (err)
200 return err;
201 schedule_work(&led->work);
202 return 0;
203 }
204
pca9532_event(struct input_dev * dev,unsigned int type,unsigned int code,int value)205 static int pca9532_event(struct input_dev *dev, unsigned int type,
206 unsigned int code, int value)
207 {
208 struct pca9532_data *data = input_get_drvdata(dev);
209
210 if (!(type == EV_SND && (code == SND_BELL || code == SND_TONE)))
211 return -1;
212
213 /* XXX: allow different kind of beeps with psc/pwm modifications */
214 if (value > 1 && value < 32767)
215 data->pwm[1] = 127;
216 else
217 data->pwm[1] = 0;
218
219 schedule_work(&data->work);
220
221 return 0;
222 }
223
pca9532_input_work(struct work_struct * work)224 static void pca9532_input_work(struct work_struct *work)
225 {
226 struct pca9532_data *data =
227 container_of(work, struct pca9532_data, work);
228 u8 maxleds = data->chip_info->num_leds;
229
230 mutex_lock(&data->update_lock);
231 i2c_smbus_write_byte_data(data->client, PCA9532_REG_PWM(maxleds, 1),
232 data->pwm[1]);
233 mutex_unlock(&data->update_lock);
234 }
235
pca9532_led_work(struct work_struct * work)236 static void pca9532_led_work(struct work_struct *work)
237 {
238 struct pca9532_led *led;
239 led = container_of(work, struct pca9532_led, work);
240 if (led->state == PCA9532_PWM0)
241 pca9532_setpwm(led->client, 0);
242 pca9532_setled(led);
243 }
244
245 #ifdef CONFIG_LEDS_PCA9532_GPIO
pca9532_gpio_request_pin(struct gpio_chip * gc,unsigned offset)246 static int pca9532_gpio_request_pin(struct gpio_chip *gc, unsigned offset)
247 {
248 struct pca9532_data *data = container_of(gc, struct pca9532_data, gpio);
249 struct pca9532_led *led = &data->leds[offset];
250
251 if (led->type == PCA9532_TYPE_GPIO)
252 return 0;
253
254 return -EBUSY;
255 }
256
pca9532_gpio_set_value(struct gpio_chip * gc,unsigned offset,int val)257 static void pca9532_gpio_set_value(struct gpio_chip *gc, unsigned offset, int val)
258 {
259 struct pca9532_data *data = container_of(gc, struct pca9532_data, gpio);
260 struct pca9532_led *led = &data->leds[offset];
261
262 if (val)
263 led->state = PCA9532_ON;
264 else
265 led->state = PCA9532_OFF;
266
267 pca9532_setled(led);
268 }
269
pca9532_gpio_get_value(struct gpio_chip * gc,unsigned offset)270 static int pca9532_gpio_get_value(struct gpio_chip *gc, unsigned offset)
271 {
272 struct pca9532_data *data = container_of(gc, struct pca9532_data, gpio);
273 unsigned char reg;
274
275 reg = i2c_smbus_read_byte_data(data->client, PCA9532_REG_INPUT(offset));
276
277 return !!(reg & (1 << (offset % 8)));
278 }
279
pca9532_gpio_direction_input(struct gpio_chip * gc,unsigned offset)280 static int pca9532_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
281 {
282 /* To use as input ensure pin is not driven */
283 pca9532_gpio_set_value(gc, offset, 0);
284
285 return 0;
286 }
287
pca9532_gpio_direction_output(struct gpio_chip * gc,unsigned offset,int val)288 static int pca9532_gpio_direction_output(struct gpio_chip *gc, unsigned offset, int val)
289 {
290 pca9532_gpio_set_value(gc, offset, val);
291
292 return 0;
293 }
294 #endif /* CONFIG_LEDS_PCA9532_GPIO */
295
pca9532_destroy_devices(struct pca9532_data * data,int n_devs)296 static int pca9532_destroy_devices(struct pca9532_data *data, int n_devs)
297 {
298 int i = n_devs;
299
300 if (!data)
301 return -EINVAL;
302
303 while (--i >= 0) {
304 switch (data->leds[i].type) {
305 case PCA9532_TYPE_NONE:
306 case PCA9532_TYPE_GPIO:
307 break;
308 case PCA9532_TYPE_LED:
309 led_classdev_unregister(&data->leds[i].ldev);
310 cancel_work_sync(&data->leds[i].work);
311 break;
312 case PCA9532_TYPE_N2100_BEEP:
313 if (data->idev != NULL) {
314 cancel_work_sync(&data->work);
315 data->idev = NULL;
316 }
317 break;
318 }
319 }
320
321 #ifdef CONFIG_LEDS_PCA9532_GPIO
322 if (data->gpio.dev)
323 gpiochip_remove(&data->gpio);
324 #endif
325
326 return 0;
327 }
328
pca9532_configure(struct i2c_client * client,struct pca9532_data * data,struct pca9532_platform_data * pdata)329 static int pca9532_configure(struct i2c_client *client,
330 struct pca9532_data *data, struct pca9532_platform_data *pdata)
331 {
332 int i, err = 0;
333 int gpios = 0;
334 u8 maxleds = data->chip_info->num_leds;
335
336 for (i = 0; i < 2; i++) {
337 data->pwm[i] = pdata->pwm[i];
338 data->psc[i] = pdata->psc[i];
339 i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, i),
340 data->pwm[i]);
341 i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, i),
342 data->psc[i]);
343 }
344
345 for (i = 0; i < data->chip_info->num_leds; i++) {
346 struct pca9532_led *led = &data->leds[i];
347 struct pca9532_led *pled = &pdata->leds[i];
348 led->client = client;
349 led->id = i;
350 led->type = pled->type;
351 switch (led->type) {
352 case PCA9532_TYPE_NONE:
353 break;
354 case PCA9532_TYPE_GPIO:
355 gpios++;
356 break;
357 case PCA9532_TYPE_LED:
358 led->state = pled->state;
359 led->name = pled->name;
360 led->ldev.name = led->name;
361 led->ldev.brightness = LED_OFF;
362 led->ldev.brightness_set = pca9532_set_brightness;
363 led->ldev.blink_set = pca9532_set_blink;
364 INIT_WORK(&led->work, pca9532_led_work);
365 err = led_classdev_register(&client->dev, &led->ldev);
366 if (err < 0) {
367 dev_err(&client->dev,
368 "couldn't register LED %s\n",
369 led->name);
370 goto exit;
371 }
372 pca9532_setled(led);
373 break;
374 case PCA9532_TYPE_N2100_BEEP:
375 BUG_ON(data->idev);
376 led->state = PCA9532_PWM1;
377 pca9532_setled(led);
378 data->idev = devm_input_allocate_device(&client->dev);
379 if (data->idev == NULL) {
380 err = -ENOMEM;
381 goto exit;
382 }
383 data->idev->name = pled->name;
384 data->idev->phys = "i2c/pca9532";
385 data->idev->id.bustype = BUS_HOST;
386 data->idev->id.vendor = 0x001f;
387 data->idev->id.product = 0x0001;
388 data->idev->id.version = 0x0100;
389 data->idev->evbit[0] = BIT_MASK(EV_SND);
390 data->idev->sndbit[0] = BIT_MASK(SND_BELL) |
391 BIT_MASK(SND_TONE);
392 data->idev->event = pca9532_event;
393 input_set_drvdata(data->idev, data);
394 INIT_WORK(&data->work, pca9532_input_work);
395 err = input_register_device(data->idev);
396 if (err) {
397 cancel_work_sync(&data->work);
398 data->idev = NULL;
399 goto exit;
400 }
401 break;
402 }
403 }
404
405 #ifdef CONFIG_LEDS_PCA9532_GPIO
406 if (gpios) {
407 data->gpio.label = "gpio-pca9532";
408 data->gpio.direction_input = pca9532_gpio_direction_input;
409 data->gpio.direction_output = pca9532_gpio_direction_output;
410 data->gpio.set = pca9532_gpio_set_value;
411 data->gpio.get = pca9532_gpio_get_value;
412 data->gpio.request = pca9532_gpio_request_pin;
413 data->gpio.can_sleep = 1;
414 data->gpio.base = pdata->gpio_base;
415 data->gpio.ngpio = data->chip_info->num_leds;
416 data->gpio.dev = &client->dev;
417 data->gpio.owner = THIS_MODULE;
418
419 err = gpiochip_add(&data->gpio);
420 if (err) {
421 /* Use data->gpio.dev as a flag for freeing gpiochip */
422 data->gpio.dev = NULL;
423 dev_warn(&client->dev, "could not add gpiochip\n");
424 } else {
425 dev_info(&client->dev, "gpios %i...%i\n",
426 data->gpio.base, data->gpio.base +
427 data->gpio.ngpio - 1);
428 }
429 }
430 #endif
431
432 return 0;
433
434 exit:
435 pca9532_destroy_devices(data, i);
436 return err;
437 }
438
pca9532_probe(struct i2c_client * client,const struct i2c_device_id * id)439 static int pca9532_probe(struct i2c_client *client,
440 const struct i2c_device_id *id)
441 {
442 struct pca9532_data *data = i2c_get_clientdata(client);
443 struct pca9532_platform_data *pca9532_pdata =
444 dev_get_platdata(&client->dev);
445
446 if (!pca9532_pdata)
447 return -EIO;
448
449 if (!i2c_check_functionality(client->adapter,
450 I2C_FUNC_SMBUS_BYTE_DATA))
451 return -EIO;
452
453 data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
454 if (!data)
455 return -ENOMEM;
456
457 data->chip_info = &pca9532_chip_info_tbl[id->driver_data];
458
459 dev_info(&client->dev, "setting platform data\n");
460 i2c_set_clientdata(client, data);
461 data->client = client;
462 mutex_init(&data->update_lock);
463
464 return pca9532_configure(client, data, pca9532_pdata);
465 }
466
pca9532_remove(struct i2c_client * client)467 static int pca9532_remove(struct i2c_client *client)
468 {
469 struct pca9532_data *data = i2c_get_clientdata(client);
470 int err;
471
472 err = pca9532_destroy_devices(data, data->chip_info->num_leds);
473 if (err)
474 return err;
475
476 return 0;
477 }
478
479 module_i2c_driver(pca9532_driver);
480
481 MODULE_AUTHOR("Riku Voipio");
482 MODULE_LICENSE("GPL");
483 MODULE_DESCRIPTION("PCA 9532 LED dimmer");
484