?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
gpio: rcar: Fix runtime PM imbalance on error
[linux/fpc-iii.git] / drivers / leds / leds-pca955x.c
blob4037c504589c186335c761ec1ff382a4f4e6087e
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright 2007-2008 Extreme Engineering Solutions, Inc.
4 *
5 * Author: Nate Case <ncase@xes-inc.com>
6 *
7 * LED driver for various PCA955x I2C LED drivers
8 *
9 * Supported devices:
10 *
11 * Device Description 7-bit slave address
12 * ------ ----------- -------------------
13 * PCA9550 2-bit driver 0x60 .. 0x61
14 * PCA9551 8-bit driver 0x60 .. 0x67
15 * PCA9552 16-bit driver 0x60 .. 0x67
16 * PCA9553/01 4-bit driver 0x62
17 * PCA9553/02 4-bit driver 0x63
18 *
19 * Philips PCA955x LED driver chips follow a register map as shown below:
20 *
21 * Control Register Description
22 * ---------------- -----------
23 * 0x0 Input register 0
24 * ..
25 * NUM_INPUT_REGS - 1 Last Input register X
26 *
27 * NUM_INPUT_REGS Frequency prescaler 0
28 * NUM_INPUT_REGS + 1 PWM register 0
29 * NUM_INPUT_REGS + 2 Frequency prescaler 1
30 * NUM_INPUT_REGS + 3 PWM register 1
31 *
32 * NUM_INPUT_REGS + 4 LED selector 0
33 * NUM_INPUT_REGS + 4
34 * + NUM_LED_REGS - 1 Last LED selector
35 *
36 * where NUM_INPUT_REGS and NUM_LED_REGS vary depending on how many
37 * bits the chip supports.
38 */
39
40 #include <linux/ctype.h>
41 #include <linux/delay.h>
42 #include <linux/err.h>
43 #include <linux/gpio.h>
44 #include <linux/i2c.h>
45 #include <linux/leds.h>
46 #include <linux/module.h>
47 #include <linux/of.h>
48 #include <linux/property.h>
49 #include <linux/slab.h>
50 #include <linux/string.h>
51
52 #include <dt-bindings/leds/leds-pca955x.h>
53
54 /* LED select registers determine the source that drives LED outputs */
55 #define PCA955X_LS_LED_ON 0x0 /* Output LOW */
56 #define PCA955X_LS_LED_OFF 0x1 /* Output HI-Z */
57 #define PCA955X_LS_BLINK0 0x2 /* Blink at PWM0 rate */
58 #define PCA955X_LS_BLINK1 0x3 /* Blink at PWM1 rate */
59
60 #define PCA955X_GPIO_INPUT LED_OFF
61 #define PCA955X_GPIO_HIGH LED_OFF
62 #define PCA955X_GPIO_LOW LED_FULL
63
64 enum pca955x_type {
65 pca9550,
66 pca9551,
67 pca9552,
68 pca9553,
69 };
70
71 struct pca955x_chipdef {
72 int bits;
73 u8 slv_addr; /* 7-bit slave address mask */
74 int slv_addr_shift; /* Number of bits to ignore */
75 };
76
77 static struct pca955x_chipdef pca955x_chipdefs[] = {
78 [pca9550] = {
79 .bits = 2,
80 .slv_addr = /* 110000x */ 0x60,
81 .slv_addr_shift = 1,
82 },
83 [pca9551] = {
84 .bits = 8,
85 .slv_addr = /* 1100xxx */ 0x60,
86 .slv_addr_shift = 3,
87 },
88 [pca9552] = {
89 .bits = 16,
90 .slv_addr = /* 1100xxx */ 0x60,
91 .slv_addr_shift = 3,
92 },
93 [pca9553] = {
94 .bits = 4,
95 .slv_addr = /* 110001x */ 0x62,
96 .slv_addr_shift = 1,
97 },
98 };
99
100 static const struct i2c_device_id pca955x_id[] = {
101 { "pca9550", pca9550 },
102 { "pca9551", pca9551 },
103 { "pca9552", pca9552 },
104 { "pca9553", pca9553 },
105 { }
106 };
107 MODULE_DEVICE_TABLE(i2c, pca955x_id);
108
109 struct pca955x {
110 struct mutex lock;
111 struct pca955x_led *leds;
112 struct pca955x_chipdef *chipdef;
113 struct i2c_client *client;
114 #ifdef CONFIG_LEDS_PCA955X_GPIO
115 struct gpio_chip gpio;
116 #endif
117 };
118
119 struct pca955x_led {
120 struct pca955x *pca955x;
121 struct led_classdev led_cdev;
122 int led_num; /* 0 .. 15 potentially */
123 char name[32];
124 u32 type;
125 const char *default_trigger;
126 };
127
128 struct pca955x_platform_data {
129 struct pca955x_led *leds;
130 int num_leds;
131 };
132
133 /* 8 bits per input register */
134 static inline int pca95xx_num_input_regs(int bits)
135 {
136 return (bits + 7) / 8;
137 }
138
139 /* 4 bits per LED selector register */
140 static inline int pca95xx_num_led_regs(int bits)
141 {
142 return (bits + 3) / 4;
143 }
144
145 /*
146 * Return an LED selector register value based on an existing one, with
147 * the appropriate 2-bit state value set for the given LED number (0-3).
148 */
149 static inline u8 pca955x_ledsel(u8 oldval, int led_num, int state)
150 {
151 return (oldval & (~(0x3 << (led_num << 1)))) |
152 ((state & 0x3) << (led_num << 1));
153 }
154
155 /*
156 * Write to frequency prescaler register, used to program the
157 * period of the PWM output. period = (PSCx + 1) / 38
158 */
159 static int pca955x_write_psc(struct i2c_client *client, int n, u8 val)
160 {
161 struct pca955x *pca955x = i2c_get_clientdata(client);
162 int ret;
163
164 ret = i2c_smbus_write_byte_data(client,
165 pca95xx_num_input_regs(pca955x->chipdef->bits) + 2*n,
166 val);
167 if (ret < 0)
168 dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
169 __func__, n, val, ret);
170 return ret;
171 }
172
173 /*
174 * Write to PWM register, which determines the duty cycle of the
175 * output. LED is OFF when the count is less than the value of this
176 * register, and ON when it is greater. If PWMx == 0, LED is always OFF.
177 *
178 * Duty cycle is (256 - PWMx) / 256
179 */
180 static int pca955x_write_pwm(struct i2c_client *client, int n, u8 val)
181 {
182 struct pca955x *pca955x = i2c_get_clientdata(client);
183 int ret;
184
185 ret = i2c_smbus_write_byte_data(client,
186 pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + 2*n,
187 val);
188 if (ret < 0)
189 dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
190 __func__, n, val, ret);
191 return ret;
192 }
193
194 /*
195 * Write to LED selector register, which determines the source that
196 * drives the LED output.
197 */
198 static int pca955x_write_ls(struct i2c_client *client, int n, u8 val)
199 {
200 struct pca955x *pca955x = i2c_get_clientdata(client);
201 int ret;
202
203 ret = i2c_smbus_write_byte_data(client,
204 pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n,
205 val);
206 if (ret < 0)
207 dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
208 __func__, n, val, ret);
209 return ret;
210 }
211
212 /*
213 * Read the LED selector register, which determines the source that
214 * drives the LED output.
215 */
216 static int pca955x_read_ls(struct i2c_client *client, int n, u8 *val)
217 {
218 struct pca955x *pca955x = i2c_get_clientdata(client);
219 int ret;
220
221 ret = i2c_smbus_read_byte_data(client,
222 pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n);
223 if (ret < 0) {
224 dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
225 __func__, n, ret);
226 return ret;
227 }
228 *val = (u8)ret;
229 return 0;
230 }
231
232 static int pca955x_led_set(struct led_classdev *led_cdev,
233 enum led_brightness value)
234 {
235 struct pca955x_led *pca955x_led;
236 struct pca955x *pca955x;
237 u8 ls;
238 int chip_ls; /* which LSx to use (0-3 potentially) */
239 int ls_led; /* which set of bits within LSx to use (0-3) */
240 int ret;
241
242 pca955x_led = container_of(led_cdev, struct pca955x_led, led_cdev);
243 pca955x = pca955x_led->pca955x;
244
245 chip_ls = pca955x_led->led_num / 4;
246 ls_led = pca955x_led->led_num % 4;
247
248 mutex_lock(&pca955x->lock);
249
250 ret = pca955x_read_ls(pca955x->client, chip_ls, &ls);
251 if (ret)
252 goto out;
253
254 switch (value) {
255 case LED_FULL:
256 ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_ON);
257 break;
258 case LED_OFF:
259 ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_OFF);
260 break;
261 case LED_HALF:
262 ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK0);
263 break;
264 default:
265 /*
266 * Use PWM1 for all other values. This has the unwanted
267 * side effect of making all LEDs on the chip share the
268 * same brightness level if set to a value other than
269 * OFF, HALF, or FULL. But, this is probably better than
270 * just turning off for all other values.
271 */
272 ret = pca955x_write_pwm(pca955x->client, 1, 255 - value);
273 if (ret)
274 goto out;
275 ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK1);
276 break;
277 }
278
279 ret = pca955x_write_ls(pca955x->client, chip_ls, ls);
280
281 out:
282 mutex_unlock(&pca955x->lock);
283
284 return ret;
285 }
286
287 #ifdef CONFIG_LEDS_PCA955X_GPIO
288 /*
289 * Read the INPUT register, which contains the state of LEDs.
290 */
291 static int pca955x_read_input(struct i2c_client *client, int n, u8 *val)
292 {
293 int ret = i2c_smbus_read_byte_data(client, n);
294
295 if (ret < 0) {
296 dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
297 __func__, n, ret);
298 return ret;
299 }
300 *val = (u8)ret;
301 return 0;
302
303 }
304
305 static int pca955x_gpio_request_pin(struct gpio_chip *gc, unsigned int offset)
306 {
307 struct pca955x *pca955x = gpiochip_get_data(gc);
308 struct pca955x_led *led = &pca955x->leds[offset];
309
310 if (led->type == PCA955X_TYPE_GPIO)
311 return 0;
312
313 return -EBUSY;
314 }
315
316 static int pca955x_set_value(struct gpio_chip *gc, unsigned int offset,
317 int val)
318 {
319 struct pca955x *pca955x = gpiochip_get_data(gc);
320 struct pca955x_led *led = &pca955x->leds[offset];
321
322 if (val)
323 return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_HIGH);
324
325 return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_LOW);
326 }
327
328 static void pca955x_gpio_set_value(struct gpio_chip *gc, unsigned int offset,
329 int val)
330 {
331 pca955x_set_value(gc, offset, val);
332 }
333
334 static int pca955x_gpio_get_value(struct gpio_chip *gc, unsigned int offset)
335 {
336 struct pca955x *pca955x = gpiochip_get_data(gc);
337 struct pca955x_led *led = &pca955x->leds[offset];
338 u8 reg = 0;
339
340 /* There is nothing we can do about errors */
341 pca955x_read_input(pca955x->client, led->led_num / 8, &reg);
342
343 return !!(reg & (1 << (led->led_num % 8)));
344 }
345
346 static int pca955x_gpio_direction_input(struct gpio_chip *gc,
347 unsigned int offset)
348 {
349 struct pca955x *pca955x = gpiochip_get_data(gc);
350 struct pca955x_led *led = &pca955x->leds[offset];
351
352 /* To use as input ensure pin is not driven. */
353 return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_INPUT);
354 }
355
356 static int pca955x_gpio_direction_output(struct gpio_chip *gc,
357 unsigned int offset, int val)
358 {
359 return pca955x_set_value(gc, offset, val);
360 }
361 #endif /* CONFIG_LEDS_PCA955X_GPIO */
362
363 static struct pca955x_platform_data *
364 pca955x_get_pdata(struct i2c_client *client, struct pca955x_chipdef *chip)
365 {
366 struct pca955x_platform_data *pdata;
367 struct fwnode_handle *child;
368 int count;
369
370 count = device_get_child_node_count(&client->dev);
371 if (!count || count > chip->bits)
372 return ERR_PTR(-ENODEV);
373
374 pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
375 if (!pdata)
376 return ERR_PTR(-ENOMEM);
377
378 pdata->leds = devm_kcalloc(&client->dev,
379 chip->bits, sizeof(struct pca955x_led),
380 GFP_KERNEL);
381 if (!pdata->leds)
382 return ERR_PTR(-ENOMEM);
383
384 device_for_each_child_node(&client->dev, child) {
385 const char *name;
386 u32 reg;
387 int res;
388
389 res = fwnode_property_read_u32(child, "reg", &reg);
390 if ((res != 0) || (reg >= chip->bits))
391 continue;
392
393 res = fwnode_property_read_string(child, "label", &name);
394 if ((res != 0) && is_of_node(child))
395 name = to_of_node(child)->name;
396
397 snprintf(pdata->leds[reg].name, sizeof(pdata->leds[reg].name),
398 "%s", name);
399
400 pdata->leds[reg].type = PCA955X_TYPE_LED;
401 fwnode_property_read_u32(child, "type", &pdata->leds[reg].type);
402 fwnode_property_read_string(child, "linux,default-trigger",
403 &pdata->leds[reg].default_trigger);
404 }
405
406 pdata->num_leds = chip->bits;
407
408 return pdata;
409 }
410
411 static const struct of_device_id of_pca955x_match[] = {
412 { .compatible = "nxp,pca9550", .data = (void *)pca9550 },
413 { .compatible = "nxp,pca9551", .data = (void *)pca9551 },
414 { .compatible = "nxp,pca9552", .data = (void *)pca9552 },
415 { .compatible = "nxp,pca9553", .data = (void *)pca9553 },
416 {},
417 };
418 MODULE_DEVICE_TABLE(of, of_pca955x_match);
419
420 static int pca955x_probe(struct i2c_client *client,
421 const struct i2c_device_id *id)
422 {
423 struct pca955x *pca955x;
424 struct pca955x_led *pca955x_led;
425 struct pca955x_chipdef *chip;
426 struct i2c_adapter *adapter;
427 int i, err;
428 struct pca955x_platform_data *pdata;
429 int ngpios = 0;
430
431 chip = &pca955x_chipdefs[id->driver_data];
432 adapter = client->adapter;
433 pdata = dev_get_platdata(&client->dev);
434 if (!pdata) {
435 pdata = pca955x_get_pdata(client, chip);
436 if (IS_ERR(pdata))
437 return PTR_ERR(pdata);
438 }
439
440 /* Make sure the slave address / chip type combo given is possible */
441 if ((client->addr & ~((1 << chip->slv_addr_shift) - 1)) !=
442 chip->slv_addr) {
443 dev_err(&client->dev, "invalid slave address %02x\n",
444 client->addr);
445 return -ENODEV;
446 }
447
448 dev_info(&client->dev, "leds-pca955x: Using %s %d-bit LED driver at "
449 "slave address 0x%02x\n",
450 client->name, chip->bits, client->addr);
451
452 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
453 return -EIO;
454
455 if (pdata->num_leds != chip->bits) {
456 dev_err(&client->dev,
457 "board info claims %d LEDs on a %d-bit chip\n",
458 pdata->num_leds, chip->bits);
459 return -ENODEV;
460 }
461
462 pca955x = devm_kzalloc(&client->dev, sizeof(*pca955x), GFP_KERNEL);
463 if (!pca955x)
464 return -ENOMEM;
465
466 pca955x->leds = devm_kcalloc(&client->dev,
467 chip->bits, sizeof(*pca955x_led), GFP_KERNEL);
468 if (!pca955x->leds)
469 return -ENOMEM;
470
471 i2c_set_clientdata(client, pca955x);
472
473 mutex_init(&pca955x->lock);
474 pca955x->client = client;
475 pca955x->chipdef = chip;
476
477 for (i = 0; i < chip->bits; i++) {
478 pca955x_led = &pca955x->leds[i];
479 pca955x_led->led_num = i;
480 pca955x_led->pca955x = pca955x;
481 pca955x_led->type = pdata->leds[i].type;
482
483 switch (pca955x_led->type) {
484 case PCA955X_TYPE_NONE:
485 break;
486 case PCA955X_TYPE_GPIO:
487 ngpios++;
488 break;
489 case PCA955X_TYPE_LED:
490 /*
491 * Platform data can specify LED names and
492 * default triggers
493 */
494 if (pdata->leds[i].name[0] == '\0')
495 snprintf(pdata->leds[i].name,
496 sizeof(pdata->leds[i].name), "%d", i);
497
498 snprintf(pca955x_led->name,
499 sizeof(pca955x_led->name), "pca955x:%s",
500 pdata->leds[i].name);
501
502 if (pdata->leds[i].default_trigger)
503 pca955x_led->led_cdev.default_trigger =
504 pdata->leds[i].default_trigger;
505
506 pca955x_led->led_cdev.name = pca955x_led->name;
507 pca955x_led->led_cdev.brightness_set_blocking =
508 pca955x_led_set;
509
510 err = devm_led_classdev_register(&client->dev,
511 &pca955x_led->led_cdev);
512 if (err)
513 return err;
514
515 /* Turn off LED */
516 err = pca955x_led_set(&pca955x_led->led_cdev, LED_OFF);
517 if (err)
518 return err;
519 }
520 }
521
522 /* PWM0 is used for half brightness or 50% duty cycle */
523 err = pca955x_write_pwm(client, 0, 255 - LED_HALF);
524 if (err)
525 return err;
526
527 /* PWM1 is used for variable brightness, default to OFF */
528 err = pca955x_write_pwm(client, 1, 0);
529 if (err)
530 return err;
531
532 /* Set to fast frequency so we do not see flashing */
533 err = pca955x_write_psc(client, 0, 0);
534 if (err)
535 return err;
536 err = pca955x_write_psc(client, 1, 0);
537 if (err)
538 return err;
539
540 #ifdef CONFIG_LEDS_PCA955X_GPIO
541 if (ngpios) {
542 pca955x->gpio.label = "gpio-pca955x";
543 pca955x->gpio.direction_input = pca955x_gpio_direction_input;
544 pca955x->gpio.direction_output = pca955x_gpio_direction_output;
545 pca955x->gpio.set = pca955x_gpio_set_value;
546 pca955x->gpio.get = pca955x_gpio_get_value;
547 pca955x->gpio.request = pca955x_gpio_request_pin;
548 pca955x->gpio.can_sleep = 1;
549 pca955x->gpio.base = -1;
550 pca955x->gpio.ngpio = ngpios;
551 pca955x->gpio.parent = &client->dev;
552 pca955x->gpio.owner = THIS_MODULE;
553
554 err = devm_gpiochip_add_data(&client->dev, &pca955x->gpio,
555 pca955x);
556 if (err) {
557 /* Use data->gpio.dev as a flag for freeing gpiochip */
558 pca955x->gpio.parent = NULL;
559 dev_warn(&client->dev, "could not add gpiochip\n");
560 return err;
561 }
562 dev_info(&client->dev, "gpios %i...%i\n",
563 pca955x->gpio.base, pca955x->gpio.base +
564 pca955x->gpio.ngpio - 1);
565 }
566 #endif
567
568 return 0;
569 }
570
571 static struct i2c_driver pca955x_driver = {
572 .driver = {
573 .name = "leds-pca955x",
574 .of_match_table = of_pca955x_match,
575 },
576 .probe = pca955x_probe,
577 .id_table = pca955x_id,
578 };
579
580 module_i2c_driver(pca955x_driver);
581
582 MODULE_AUTHOR("Nate Case <ncase@xes-inc.com>");
583 MODULE_DESCRIPTION("PCA955x LED driver");
584 MODULE_LICENSE("GPL v2");
Linux with added FPC-III support