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/driver.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 ibm_pca9552,
69 pca9553,
70 };
71
72 struct pca955x_chipdef {
73 int bits;
74 u8 slv_addr; /* 7-bit slave address mask */
75 int slv_addr_shift; /* Number of bits to ignore */
76 };
77
78 static struct pca955x_chipdef pca955x_chipdefs[] = {
79 [pca9550] = {
80 .bits = 2,
81 .slv_addr = /* 110000x */ 0x60,
82 .slv_addr_shift = 1,
83 },
84 [pca9551] = {
85 .bits = 8,
86 .slv_addr = /* 1100xxx */ 0x60,
87 .slv_addr_shift = 3,
88 },
89 [pca9552] = {
90 .bits = 16,
91 .slv_addr = /* 1100xxx */ 0x60,
92 .slv_addr_shift = 3,
93 },
94 [ibm_pca9552] = {
95 .bits = 16,
96 .slv_addr = /* 0110xxx */ 0x30,
97 .slv_addr_shift = 3,
98 },
99 [pca9553] = {
100 .bits = 4,
101 .slv_addr = /* 110001x */ 0x62,
102 .slv_addr_shift = 1,
103 },
104 };
105
106 static const struct i2c_device_id pca955x_id[] = {
107 { "pca9550", pca9550 },
108 { "pca9551", pca9551 },
109 { "pca9552", pca9552 },
110 { "ibm-pca9552", ibm_pca9552 },
111 { "pca9553", pca9553 },
112 { }
113 };
114 MODULE_DEVICE_TABLE(i2c, pca955x_id);
115
116 struct pca955x {
117 struct mutex lock;
118 struct pca955x_led *leds;
119 struct pca955x_chipdef *chipdef;
120 struct i2c_client *client;
121 #ifdef CONFIG_LEDS_PCA955X_GPIO
122 struct gpio_chip gpio;
123 #endif
124 };
125
126 struct pca955x_led {
127 struct pca955x *pca955x;
128 struct led_classdev led_cdev;
129 int led_num; /* 0 .. 15 potentially */
130 u32 type;
131 int default_state;
132 struct fwnode_handle *fwnode;
133 };
134
135 struct pca955x_platform_data {
136 struct pca955x_led *leds;
137 int num_leds;
138 };
139
140 /* 8 bits per input register */
pca95xx_num_input_regs(int bits)141 static inline int pca95xx_num_input_regs(int bits)
142 {
143 return (bits + 7) / 8;
144 }
145
146 /* 4 bits per LED selector register */
pca95xx_num_led_regs(int bits)147 static inline int pca95xx_num_led_regs(int bits)
148 {
149 return (bits + 3) / 4;
150 }
151
152 /*
153 * Return an LED selector register value based on an existing one, with
154 * the appropriate 2-bit state value set for the given LED number (0-3).
155 */
pca955x_ledsel(u8 oldval,int led_num,int state)156 static inline u8 pca955x_ledsel(u8 oldval, int led_num, int state)
157 {
158 return (oldval & (~(0x3 << (led_num << 1)))) |
159 ((state & 0x3) << (led_num << 1));
160 }
161
162 /*
163 * Write to frequency prescaler register, used to program the
164 * period of the PWM output. period = (PSCx + 1) / 38
165 */
pca955x_write_psc(struct i2c_client * client,int n,u8 val)166 static int pca955x_write_psc(struct i2c_client *client, int n, u8 val)
167 {
168 struct pca955x *pca955x = i2c_get_clientdata(client);
169 u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + (2 * n);
170 int ret;
171
172 ret = i2c_smbus_write_byte_data(client, cmd, val);
173 if (ret < 0)
174 dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
175 __func__, n, val, ret);
176 return ret;
177 }
178
179 /*
180 * Write to PWM register, which determines the duty cycle of the
181 * output. LED is OFF when the count is less than the value of this
182 * register, and ON when it is greater. If PWMx == 0, LED is always OFF.
183 *
184 * Duty cycle is (256 - PWMx) / 256
185 */
pca955x_write_pwm(struct i2c_client * client,int n,u8 val)186 static int pca955x_write_pwm(struct i2c_client *client, int n, u8 val)
187 {
188 struct pca955x *pca955x = i2c_get_clientdata(client);
189 u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + (2 * n);
190 int ret;
191
192 ret = i2c_smbus_write_byte_data(client, cmd, val);
193 if (ret < 0)
194 dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
195 __func__, n, val, ret);
196 return ret;
197 }
198
199 /*
200 * Write to LED selector register, which determines the source that
201 * drives the LED output.
202 */
pca955x_write_ls(struct i2c_client * client,int n,u8 val)203 static int pca955x_write_ls(struct i2c_client *client, int n, u8 val)
204 {
205 struct pca955x *pca955x = i2c_get_clientdata(client);
206 u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n;
207 int ret;
208
209 ret = i2c_smbus_write_byte_data(client, cmd, val);
210 if (ret < 0)
211 dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
212 __func__, n, val, ret);
213 return ret;
214 }
215
216 /*
217 * Read the LED selector register, which determines the source that
218 * drives the LED output.
219 */
pca955x_read_ls(struct i2c_client * client,int n,u8 * val)220 static int pca955x_read_ls(struct i2c_client *client, int n, u8 *val)
221 {
222 struct pca955x *pca955x = i2c_get_clientdata(client);
223 u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n;
224 int ret;
225
226 ret = i2c_smbus_read_byte_data(client, cmd);
227 if (ret < 0) {
228 dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
229 __func__, n, ret);
230 return ret;
231 }
232 *val = (u8)ret;
233 return 0;
234 }
235
pca955x_read_pwm(struct i2c_client * client,int n,u8 * val)236 static int pca955x_read_pwm(struct i2c_client *client, int n, u8 *val)
237 {
238 struct pca955x *pca955x = i2c_get_clientdata(client);
239 u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + (2 * n);
240 int ret;
241
242 ret = i2c_smbus_read_byte_data(client, cmd);
243 if (ret < 0) {
244 dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
245 __func__, n, ret);
246 return ret;
247 }
248 *val = (u8)ret;
249 return 0;
250 }
251
pca955x_led_get(struct led_classdev * led_cdev)252 static enum led_brightness pca955x_led_get(struct led_classdev *led_cdev)
253 {
254 struct pca955x_led *pca955x_led = container_of(led_cdev,
255 struct pca955x_led,
256 led_cdev);
257 struct pca955x *pca955x = pca955x_led->pca955x;
258 u8 ls, pwm;
259 int ret;
260
261 ret = pca955x_read_ls(pca955x->client, pca955x_led->led_num / 4, &ls);
262 if (ret)
263 return ret;
264
265 ls = (ls >> ((pca955x_led->led_num % 4) << 1)) & 0x3;
266 switch (ls) {
267 case PCA955X_LS_LED_ON:
268 ret = LED_FULL;
269 break;
270 case PCA955X_LS_LED_OFF:
271 ret = LED_OFF;
272 break;
273 case PCA955X_LS_BLINK0:
274 ret = LED_HALF;
275 break;
276 case PCA955X_LS_BLINK1:
277 ret = pca955x_read_pwm(pca955x->client, 1, &pwm);
278 if (ret)
279 return ret;
280 ret = 255 - pwm;
281 break;
282 }
283
284 return ret;
285 }
286
pca955x_led_set(struct led_classdev * led_cdev,enum led_brightness value)287 static int pca955x_led_set(struct led_classdev *led_cdev,
288 enum led_brightness value)
289 {
290 struct pca955x_led *pca955x_led;
291 struct pca955x *pca955x;
292 u8 ls;
293 int chip_ls; /* which LSx to use (0-3 potentially) */
294 int ls_led; /* which set of bits within LSx to use (0-3) */
295 int ret;
296
297 pca955x_led = container_of(led_cdev, struct pca955x_led, led_cdev);
298 pca955x = pca955x_led->pca955x;
299
300 chip_ls = pca955x_led->led_num / 4;
301 ls_led = pca955x_led->led_num % 4;
302
303 mutex_lock(&pca955x->lock);
304
305 ret = pca955x_read_ls(pca955x->client, chip_ls, &ls);
306 if (ret)
307 goto out;
308
309 switch (value) {
310 case LED_FULL:
311 ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_ON);
312 break;
313 case LED_OFF:
314 ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_OFF);
315 break;
316 case LED_HALF:
317 ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK0);
318 break;
319 default:
320 /*
321 * Use PWM1 for all other values. This has the unwanted
322 * side effect of making all LEDs on the chip share the
323 * same brightness level if set to a value other than
324 * OFF, HALF, or FULL. But, this is probably better than
325 * just turning off for all other values.
326 */
327 ret = pca955x_write_pwm(pca955x->client, 1, 255 - value);
328 if (ret)
329 goto out;
330 ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK1);
331 break;
332 }
333
334 ret = pca955x_write_ls(pca955x->client, chip_ls, ls);
335
336 out:
337 mutex_unlock(&pca955x->lock);
338
339 return ret;
340 }
341
342 #ifdef CONFIG_LEDS_PCA955X_GPIO
343 /*
344 * Read the INPUT register, which contains the state of LEDs.
345 */
pca955x_read_input(struct i2c_client * client,int n,u8 * val)346 static int pca955x_read_input(struct i2c_client *client, int n, u8 *val)
347 {
348 int ret = i2c_smbus_read_byte_data(client, n);
349
350 if (ret < 0) {
351 dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
352 __func__, n, ret);
353 return ret;
354 }
355 *val = (u8)ret;
356 return 0;
357
358 }
359
pca955x_gpio_request_pin(struct gpio_chip * gc,unsigned int offset)360 static int pca955x_gpio_request_pin(struct gpio_chip *gc, unsigned int offset)
361 {
362 struct pca955x *pca955x = gpiochip_get_data(gc);
363 struct pca955x_led *led = &pca955x->leds[offset];
364
365 if (led->type == PCA955X_TYPE_GPIO)
366 return 0;
367
368 return -EBUSY;
369 }
370
pca955x_set_value(struct gpio_chip * gc,unsigned int offset,int val)371 static int pca955x_set_value(struct gpio_chip *gc, unsigned int offset,
372 int val)
373 {
374 struct pca955x *pca955x = gpiochip_get_data(gc);
375 struct pca955x_led *led = &pca955x->leds[offset];
376
377 if (val)
378 return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_HIGH);
379
380 return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_LOW);
381 }
382
pca955x_gpio_set_value(struct gpio_chip * gc,unsigned int offset,int val)383 static void pca955x_gpio_set_value(struct gpio_chip *gc, unsigned int offset,
384 int val)
385 {
386 pca955x_set_value(gc, offset, val);
387 }
388
pca955x_gpio_get_value(struct gpio_chip * gc,unsigned int offset)389 static int pca955x_gpio_get_value(struct gpio_chip *gc, unsigned int offset)
390 {
391 struct pca955x *pca955x = gpiochip_get_data(gc);
392 struct pca955x_led *led = &pca955x->leds[offset];
393 u8 reg = 0;
394
395 /* There is nothing we can do about errors */
396 pca955x_read_input(pca955x->client, led->led_num / 8, ®);
397
398 return !!(reg & (1 << (led->led_num % 8)));
399 }
400
pca955x_gpio_direction_input(struct gpio_chip * gc,unsigned int offset)401 static int pca955x_gpio_direction_input(struct gpio_chip *gc,
402 unsigned int offset)
403 {
404 struct pca955x *pca955x = gpiochip_get_data(gc);
405 struct pca955x_led *led = &pca955x->leds[offset];
406
407 /* To use as input ensure pin is not driven. */
408 return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_INPUT);
409 }
410
pca955x_gpio_direction_output(struct gpio_chip * gc,unsigned int offset,int val)411 static int pca955x_gpio_direction_output(struct gpio_chip *gc,
412 unsigned int offset, int val)
413 {
414 return pca955x_set_value(gc, offset, val);
415 }
416 #endif /* CONFIG_LEDS_PCA955X_GPIO */
417
418 static struct pca955x_platform_data *
pca955x_get_pdata(struct i2c_client * client,struct pca955x_chipdef * chip)419 pca955x_get_pdata(struct i2c_client *client, struct pca955x_chipdef *chip)
420 {
421 struct pca955x_platform_data *pdata;
422 struct pca955x_led *led;
423 struct fwnode_handle *child;
424 int count;
425
426 count = device_get_child_node_count(&client->dev);
427 if (!count || count > chip->bits)
428 return ERR_PTR(-ENODEV);
429
430 pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
431 if (!pdata)
432 return ERR_PTR(-ENOMEM);
433
434 pdata->leds = devm_kcalloc(&client->dev,
435 chip->bits, sizeof(struct pca955x_led),
436 GFP_KERNEL);
437 if (!pdata->leds)
438 return ERR_PTR(-ENOMEM);
439
440 device_for_each_child_node(&client->dev, child) {
441 const char *state;
442 u32 reg;
443 int res;
444
445 res = fwnode_property_read_u32(child, "reg", ®);
446 if ((res != 0) || (reg >= chip->bits))
447 continue;
448
449 led = &pdata->leds[reg];
450 led->type = PCA955X_TYPE_LED;
451 led->fwnode = child;
452 fwnode_property_read_u32(child, "type", &led->type);
453
454 if (!fwnode_property_read_string(child, "default-state",
455 &state)) {
456 if (!strcmp(state, "keep"))
457 led->default_state = LEDS_GPIO_DEFSTATE_KEEP;
458 else if (!strcmp(state, "on"))
459 led->default_state = LEDS_GPIO_DEFSTATE_ON;
460 else
461 led->default_state = LEDS_GPIO_DEFSTATE_OFF;
462 } else {
463 led->default_state = LEDS_GPIO_DEFSTATE_OFF;
464 }
465 }
466
467 pdata->num_leds = chip->bits;
468
469 return pdata;
470 }
471
472 static const struct of_device_id of_pca955x_match[] = {
473 { .compatible = "nxp,pca9550", .data = (void *)pca9550 },
474 { .compatible = "nxp,pca9551", .data = (void *)pca9551 },
475 { .compatible = "nxp,pca9552", .data = (void *)pca9552 },
476 { .compatible = "ibm,pca9552", .data = (void *)ibm_pca9552 },
477 { .compatible = "nxp,pca9553", .data = (void *)pca9553 },
478 {},
479 };
480 MODULE_DEVICE_TABLE(of, of_pca955x_match);
481
pca955x_probe(struct i2c_client * client)482 static int pca955x_probe(struct i2c_client *client)
483 {
484 struct pca955x *pca955x;
485 struct pca955x_led *pca955x_led;
486 struct pca955x_chipdef *chip;
487 struct led_classdev *led;
488 struct led_init_data init_data;
489 struct i2c_adapter *adapter;
490 int i, err;
491 struct pca955x_platform_data *pdata;
492 int ngpios = 0;
493 bool set_default_label = false;
494 bool keep_pwm = false;
495 char default_label[8];
496 enum pca955x_type chip_type;
497 const void *md = device_get_match_data(&client->dev);
498
499 if (md) {
500 chip_type = (enum pca955x_type)md;
501 } else {
502 const struct i2c_device_id *id = i2c_match_id(pca955x_id,
503 client);
504
505 if (id) {
506 chip_type = (enum pca955x_type)id->driver_data;
507 } else {
508 dev_err(&client->dev, "unknown chip\n");
509 return -ENODEV;
510 }
511 }
512
513 chip = &pca955x_chipdefs[chip_type];
514 adapter = client->adapter;
515 pdata = dev_get_platdata(&client->dev);
516 if (!pdata) {
517 pdata = pca955x_get_pdata(client, chip);
518 if (IS_ERR(pdata))
519 return PTR_ERR(pdata);
520 }
521
522 /* Make sure the slave address / chip type combo given is possible */
523 if ((client->addr & ~((1 << chip->slv_addr_shift) - 1)) !=
524 chip->slv_addr) {
525 dev_err(&client->dev, "invalid slave address %02x\n",
526 client->addr);
527 return -ENODEV;
528 }
529
530 dev_info(&client->dev, "leds-pca955x: Using %s %d-bit LED driver at "
531 "slave address 0x%02x\n", client->name, chip->bits,
532 client->addr);
533
534 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
535 return -EIO;
536
537 if (pdata->num_leds != chip->bits) {
538 dev_err(&client->dev,
539 "board info claims %d LEDs on a %d-bit chip\n",
540 pdata->num_leds, chip->bits);
541 return -ENODEV;
542 }
543
544 pca955x = devm_kzalloc(&client->dev, sizeof(*pca955x), GFP_KERNEL);
545 if (!pca955x)
546 return -ENOMEM;
547
548 pca955x->leds = devm_kcalloc(&client->dev, chip->bits,
549 sizeof(*pca955x_led), GFP_KERNEL);
550 if (!pca955x->leds)
551 return -ENOMEM;
552
553 i2c_set_clientdata(client, pca955x);
554
555 mutex_init(&pca955x->lock);
556 pca955x->client = client;
557 pca955x->chipdef = chip;
558
559 init_data.devname_mandatory = false;
560 init_data.devicename = "pca955x";
561
562 for (i = 0; i < chip->bits; i++) {
563 pca955x_led = &pca955x->leds[i];
564 pca955x_led->led_num = i;
565 pca955x_led->pca955x = pca955x;
566 pca955x_led->type = pdata->leds[i].type;
567
568 switch (pca955x_led->type) {
569 case PCA955X_TYPE_NONE:
570 break;
571 case PCA955X_TYPE_GPIO:
572 ngpios++;
573 break;
574 case PCA955X_TYPE_LED:
575 led = &pca955x_led->led_cdev;
576 led->brightness_set_blocking = pca955x_led_set;
577 led->brightness_get = pca955x_led_get;
578
579 if (pdata->leds[i].default_state ==
580 LEDS_GPIO_DEFSTATE_OFF) {
581 err = pca955x_led_set(led, LED_OFF);
582 if (err)
583 return err;
584 } else if (pdata->leds[i].default_state ==
585 LEDS_GPIO_DEFSTATE_ON) {
586 err = pca955x_led_set(led, LED_FULL);
587 if (err)
588 return err;
589 }
590
591 init_data.fwnode = pdata->leds[i].fwnode;
592
593 if (is_of_node(init_data.fwnode)) {
594 if (to_of_node(init_data.fwnode)->name[0] ==
595 '\0')
596 set_default_label = true;
597 else
598 set_default_label = false;
599 } else {
600 set_default_label = true;
601 }
602
603 if (set_default_label) {
604 snprintf(default_label, sizeof(default_label),
605 "%d", i);
606 init_data.default_label = default_label;
607 } else {
608 init_data.default_label = NULL;
609 }
610
611 err = devm_led_classdev_register_ext(&client->dev, led,
612 &init_data);
613 if (err)
614 return err;
615
616 /*
617 * For default-state == "keep", let the core update the
618 * brightness from the hardware, then check the
619 * brightness to see if it's using PWM1. If so, PWM1
620 * should not be written below.
621 */
622 if (pdata->leds[i].default_state ==
623 LEDS_GPIO_DEFSTATE_KEEP) {
624 if (led->brightness != LED_FULL &&
625 led->brightness != LED_OFF &&
626 led->brightness != LED_HALF)
627 keep_pwm = true;
628 }
629 }
630 }
631
632 /* PWM0 is used for half brightness or 50% duty cycle */
633 err = pca955x_write_pwm(client, 0, 255 - LED_HALF);
634 if (err)
635 return err;
636
637 if (!keep_pwm) {
638 /* PWM1 is used for variable brightness, default to OFF */
639 err = pca955x_write_pwm(client, 1, 0);
640 if (err)
641 return err;
642 }
643
644 /* Set to fast frequency so we do not see flashing */
645 err = pca955x_write_psc(client, 0, 0);
646 if (err)
647 return err;
648 err = pca955x_write_psc(client, 1, 0);
649 if (err)
650 return err;
651
652 #ifdef CONFIG_LEDS_PCA955X_GPIO
653 if (ngpios) {
654 pca955x->gpio.label = "gpio-pca955x";
655 pca955x->gpio.direction_input = pca955x_gpio_direction_input;
656 pca955x->gpio.direction_output = pca955x_gpio_direction_output;
657 pca955x->gpio.set = pca955x_gpio_set_value;
658 pca955x->gpio.get = pca955x_gpio_get_value;
659 pca955x->gpio.request = pca955x_gpio_request_pin;
660 pca955x->gpio.can_sleep = 1;
661 pca955x->gpio.base = -1;
662 pca955x->gpio.ngpio = ngpios;
663 pca955x->gpio.parent = &client->dev;
664 pca955x->gpio.owner = THIS_MODULE;
665
666 err = devm_gpiochip_add_data(&client->dev, &pca955x->gpio,
667 pca955x);
668 if (err) {
669 /* Use data->gpio.dev as a flag for freeing gpiochip */
670 pca955x->gpio.parent = NULL;
671 dev_warn(&client->dev, "could not add gpiochip\n");
672 return err;
673 }
674 dev_info(&client->dev, "gpios %i...%i\n",
675 pca955x->gpio.base, pca955x->gpio.base +
676 pca955x->gpio.ngpio - 1);
677 }
678 #endif
679
680 return 0;
681 }
682
683 static struct i2c_driver pca955x_driver = {
684 .driver = {
685 .name = "leds-pca955x",
686 .of_match_table = of_pca955x_match,
687 },
688 .probe_new = pca955x_probe,
689 .id_table = pca955x_id,
690 };
691
692 module_i2c_driver(pca955x_driver);
693
694 MODULE_AUTHOR("Nate Case <ncase@xes-inc.com>");
695 MODULE_DESCRIPTION("PCA955x LED driver");
696 MODULE_LICENSE("GPL v2");
697