drivers/leds/leds-pca955x.c

   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 */
 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 */
 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  */
 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  */
 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  */
 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  */
 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  */
 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
 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
 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
 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  */
 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
 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
 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
 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
 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, &reg);
 397
 398         return !!(reg & (1 << (led->led_num % 8)));
 399 }
 400
 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
 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 *
 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", &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
 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");