drivers/gpio/gpio-pca953x.c

   1 /*
   2  *  PCA953x 4/8/16/24/40 bit I/O ports
   3  *
   4  *  Copyright (C) 2005 Ben Gardner <bgardner@wabtec.com>
   5  *  Copyright (C) 2007 Marvell International Ltd.
   6  *
   7  *  Derived from drivers/i2c/chips/pca9539.c
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License as published by
  11  *  the Free Software Foundation; version 2 of the License.
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/init.h>
  16 #include <linux/gpio.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/i2c.h>
  19 #include <linux/platform_data/pca953x.h>
  20 #include <linux/slab.h>
  21 #include <asm/unaligned.h>
  22 #include <linux/of_platform.h>
  23 #include <linux/acpi.h>
  24 #include <linux/regulator/consumer.h>
  25
  26 #define PCA953X_INPUT           0
  27 #define PCA953X_OUTPUT          1
  28 #define PCA953X_INVERT          2
  29 #define PCA953X_DIRECTION       3
  30
  31 #define REG_ADDR_AI             0x80
  32
  33 #define PCA957X_IN              0
  34 #define PCA957X_INVRT           1
  35 #define PCA957X_BKEN            2
  36 #define PCA957X_PUPD            3
  37 #define PCA957X_CFG             4
  38 #define PCA957X_OUT             5
  39 #define PCA957X_MSK             6
  40 #define PCA957X_INTS            7
  41
  42 #define PCAL953X_IN_LATCH       34
  43 #define PCAL953X_INT_MASK       37
  44 #define PCAL953X_INT_STAT       38
  45
  46 #define PCA_GPIO_MASK           0x00FF
  47 #define PCA_INT                 0x0100
  48 #define PCA_PCAL                0x0200
  49 #define PCA953X_TYPE            0x1000
  50 #define PCA957X_TYPE            0x2000
  51 #define PCA_TYPE_MASK           0xF000
  52
  53 #define PCA_CHIP_TYPE(x)        ((x) & PCA_TYPE_MASK)
  54
  55 static const struct i2c_device_id pca953x_id[] = {
  56         { "pca9505", 40 | PCA953X_TYPE | PCA_INT, },
  57         { "pca9534", 8  | PCA953X_TYPE | PCA_INT, },
  58         { "pca9535", 16 | PCA953X_TYPE | PCA_INT, },
  59         { "pca9536", 4  | PCA953X_TYPE, },
  60         { "pca9537", 4  | PCA953X_TYPE | PCA_INT, },
  61         { "pca9538", 8  | PCA953X_TYPE | PCA_INT, },
  62         { "pca9539", 16 | PCA953X_TYPE | PCA_INT, },
  63         { "pca9554", 8  | PCA953X_TYPE | PCA_INT, },
  64         { "pca9555", 16 | PCA953X_TYPE | PCA_INT, },
  65         { "pca9556", 8  | PCA953X_TYPE, },
  66         { "pca9557", 8  | PCA953X_TYPE, },
  67         { "pca9574", 8  | PCA957X_TYPE | PCA_INT, },
  68         { "pca9575", 16 | PCA957X_TYPE | PCA_INT, },
  69         { "pca9698", 40 | PCA953X_TYPE, },
  70
  71         { "pcal9555a", 16 | PCA953X_TYPE | PCA_INT | PCA_PCAL, },
  72
  73         { "max7310", 8  | PCA953X_TYPE, },
  74         { "max7312", 16 | PCA953X_TYPE | PCA_INT, },
  75         { "max7313", 16 | PCA953X_TYPE | PCA_INT, },
  76         { "max7315", 8  | PCA953X_TYPE | PCA_INT, },
  77         { "pca6107", 8  | PCA953X_TYPE | PCA_INT, },
  78         { "tca6408", 8  | PCA953X_TYPE | PCA_INT, },
  79         { "tca6416", 16 | PCA953X_TYPE | PCA_INT, },
  80         { "tca6424", 24 | PCA953X_TYPE | PCA_INT, },
  81         { "tca9539", 16 | PCA953X_TYPE | PCA_INT, },
  82         { "xra1202", 8  | PCA953X_TYPE },
  83         { }
  84 };
  85 MODULE_DEVICE_TABLE(i2c, pca953x_id);
  86
  87 static const struct acpi_device_id pca953x_acpi_ids[] = {
  88         { "INT3491", 16 | PCA953X_TYPE | PCA_INT | PCA_PCAL, },
  89         { }
  90 };
  91 MODULE_DEVICE_TABLE(acpi, pca953x_acpi_ids);
  92
  93 #define MAX_BANK 5
  94 #define BANK_SZ 8
  95
  96 #define NBANK(chip) DIV_ROUND_UP(chip->gpio_chip.ngpio, BANK_SZ)
  97
  98 struct pca953x_reg_config {
  99         int direction;
 100         int output;
 101         int input;
 102 };
 103
 104 static const struct pca953x_reg_config pca953x_regs = {
 105         .direction = PCA953X_DIRECTION,
 106         .output = PCA953X_OUTPUT,
 107         .input = PCA953X_INPUT,
 108 };
 109
 110 static const struct pca953x_reg_config pca957x_regs = {
 111         .direction = PCA957X_CFG,
 112         .output = PCA957X_OUT,
 113         .input = PCA957X_IN,
 114 };
 115
 116 struct pca953x_chip {
 117         unsigned gpio_start;
 118         u8 reg_output[MAX_BANK];
 119         u8 reg_direction[MAX_BANK];
 120         struct mutex i2c_lock;
 121
 122 #ifdef CONFIG_GPIO_PCA953X_IRQ
 123         struct mutex irq_lock;
 124         u8 irq_mask[MAX_BANK];
 125         u8 irq_stat[MAX_BANK];
 126         u8 irq_trig_raise[MAX_BANK];
 127         u8 irq_trig_fall[MAX_BANK];
 128 #endif
 129
 130         struct i2c_client *client;
 131         struct gpio_chip gpio_chip;
 132         const char *const *names;
 133         unsigned long driver_data;
 134         struct regulator *regulator;
 135
 136         const struct pca953x_reg_config *regs;
 137
 138         int (*write_regs)(struct pca953x_chip *, int, u8 *);
 139         int (*read_regs)(struct pca953x_chip *, int, u8 *);
 140 };
 141
 142 static int pca953x_read_single(struct pca953x_chip *chip, int reg, u32 *val,
 143                                 int off)
 144 {
 145         int ret;
 146         int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
 147         int offset = off / BANK_SZ;
 148
 149         ret = i2c_smbus_read_byte_data(chip->client,
 150                                 (reg << bank_shift) + offset);
 151         *val = ret;
 152
 153         if (ret < 0) {
 154                 dev_err(&chip->client->dev, "failed reading register\n");
 155                 return ret;
 156         }
 157
 158         return 0;
 159 }
 160
 161 static int pca953x_write_single(struct pca953x_chip *chip, int reg, u32 val,
 162                                 int off)
 163 {
 164         int ret;
 165         int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
 166         int offset = off / BANK_SZ;
 167
 168         ret = i2c_smbus_write_byte_data(chip->client,
 169                                         (reg << bank_shift) + offset, val);
 170
 171         if (ret < 0) {
 172                 dev_err(&chip->client->dev, "failed writing register\n");
 173                 return ret;
 174         }
 175
 176         return 0;
 177 }
 178
 179 static int pca953x_write_regs_8(struct pca953x_chip *chip, int reg, u8 *val)
 180 {
 181         return i2c_smbus_write_byte_data(chip->client, reg, *val);
 182 }
 183
 184 static int pca953x_write_regs_16(struct pca953x_chip *chip, int reg, u8 *val)
 185 {
 186         __le16 word = cpu_to_le16(get_unaligned((u16 *)val));
 187
 188         return i2c_smbus_write_word_data(chip->client,
 189                                          reg << 1, (__force u16)word);
 190 }
 191
 192 static int pca957x_write_regs_16(struct pca953x_chip *chip, int reg, u8 *val)
 193 {
 194         int ret;
 195
 196         ret = i2c_smbus_write_byte_data(chip->client, reg << 1, val[0]);
 197         if (ret < 0)
 198                 return ret;
 199
 200         return i2c_smbus_write_byte_data(chip->client, (reg << 1) + 1, val[1]);
 201 }
 202
 203 static int pca953x_write_regs_24(struct pca953x_chip *chip, int reg, u8 *val)
 204 {
 205         int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
 206
 207         return i2c_smbus_write_i2c_block_data(chip->client,
 208                                               (reg << bank_shift) | REG_ADDR_AI,
 209                                               NBANK(chip), val);
 210 }
 211
 212 static int pca953x_write_regs(struct pca953x_chip *chip, int reg, u8 *val)
 213 {
 214         int ret = 0;
 215
 216         ret = chip->write_regs(chip, reg, val);
 217         if (ret < 0) {
 218                 dev_err(&chip->client->dev, "failed writing register\n");
 219                 return ret;
 220         }
 221
 222         return 0;
 223 }
 224
 225 static int pca953x_read_regs_8(struct pca953x_chip *chip, int reg, u8 *val)
 226 {
 227         int ret;
 228
 229         ret = i2c_smbus_read_byte_data(chip->client, reg);
 230         *val = ret;
 231
 232         return ret;
 233 }
 234
 235 static int pca953x_read_regs_16(struct pca953x_chip *chip, int reg, u8 *val)
 236 {
 237         int ret;
 238
 239         ret = i2c_smbus_read_word_data(chip->client, reg << 1);
 240         val[0] = (u16)ret & 0xFF;
 241         val[1] = (u16)ret >> 8;
 242
 243         return ret;
 244 }
 245
 246 static int pca953x_read_regs_24(struct pca953x_chip *chip, int reg, u8 *val)
 247 {
 248         int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
 249
 250         return i2c_smbus_read_i2c_block_data(chip->client,
 251                                              (reg << bank_shift) | REG_ADDR_AI,
 252                                              NBANK(chip), val);
 253 }
 254
 255 static int pca953x_read_regs(struct pca953x_chip *chip, int reg, u8 *val)
 256 {
 257         int ret;
 258
 259         ret = chip->read_regs(chip, reg, val);
 260         if (ret < 0) {
 261                 dev_err(&chip->client->dev, "failed reading register\n");
 262                 return ret;
 263         }
 264
 265         return 0;
 266 }
 267
 268 static int pca953x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
 269 {
 270         struct pca953x_chip *chip = gpiochip_get_data(gc);
 271         u8 reg_val;
 272         int ret;
 273
 274         mutex_lock(&chip->i2c_lock);
 275         reg_val = chip->reg_direction[off / BANK_SZ] | (1u << (off % BANK_SZ));
 276
 277         ret = pca953x_write_single(chip, chip->regs->direction, reg_val, off);
 278         if (ret)
 279                 goto exit;
 280
 281         chip->reg_direction[off / BANK_SZ] = reg_val;
 282 exit:
 283         mutex_unlock(&chip->i2c_lock);
 284         return ret;
 285 }
 286
 287 static int pca953x_gpio_direction_output(struct gpio_chip *gc,
 288                 unsigned off, int val)
 289 {
 290         struct pca953x_chip *chip = gpiochip_get_data(gc);
 291         u8 reg_val;
 292         int ret;
 293
 294         mutex_lock(&chip->i2c_lock);
 295         /* set output level */
 296         if (val)
 297                 reg_val = chip->reg_output[off / BANK_SZ]
 298                         | (1u << (off % BANK_SZ));
 299         else
 300                 reg_val = chip->reg_output[off / BANK_SZ]
 301                         & ~(1u << (off % BANK_SZ));
 302
 303         ret = pca953x_write_single(chip, chip->regs->output, reg_val, off);
 304         if (ret)
 305                 goto exit;
 306
 307         chip->reg_output[off / BANK_SZ] = reg_val;
 308
 309         /* then direction */
 310         reg_val = chip->reg_direction[off / BANK_SZ] & ~(1u << (off % BANK_SZ));
 311         ret = pca953x_write_single(chip, chip->regs->direction, reg_val, off);
 312         if (ret)
 313                 goto exit;
 314
 315         chip->reg_direction[off / BANK_SZ] = reg_val;
 316 exit:
 317         mutex_unlock(&chip->i2c_lock);
 318         return ret;
 319 }
 320
 321 static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off)
 322 {
 323         struct pca953x_chip *chip = gpiochip_get_data(gc);
 324         u32 reg_val;
 325         int ret;
 326
 327         mutex_lock(&chip->i2c_lock);
 328         ret = pca953x_read_single(chip, chip->regs->input, &reg_val, off);
 329         mutex_unlock(&chip->i2c_lock);
 330         if (ret < 0) {
 331                 /* NOTE:  diagnostic already emitted; that's all we should
 332                  * do unless gpio_*_value_cansleep() calls become different
 333                  * from their nonsleeping siblings (and report faults).
 334                  */
 335                 return 0;
 336         }
 337
 338         return (reg_val & (1u << (off % BANK_SZ))) ? 1 : 0;
 339 }
 340
 341 static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
 342 {
 343         struct pca953x_chip *chip = gpiochip_get_data(gc);
 344         u8 reg_val;
 345         int ret;
 346
 347         mutex_lock(&chip->i2c_lock);
 348         if (val)
 349                 reg_val = chip->reg_output[off / BANK_SZ]
 350                         | (1u << (off % BANK_SZ));
 351         else
 352                 reg_val = chip->reg_output[off / BANK_SZ]
 353                         & ~(1u << (off % BANK_SZ));
 354
 355         ret = pca953x_write_single(chip, chip->regs->output, reg_val, off);
 356         if (ret)
 357                 goto exit;
 358
 359         chip->reg_output[off / BANK_SZ] = reg_val;
 360 exit:
 361         mutex_unlock(&chip->i2c_lock);
 362 }
 363
 364 static void pca953x_gpio_set_multiple(struct gpio_chip *gc,
 365                                       unsigned long *mask, unsigned long *bits)
 366 {
 367         struct pca953x_chip *chip = gpiochip_get_data(gc);
 368         unsigned int bank_mask, bank_val;
 369         int bank_shift, bank;
 370         u8 reg_val[MAX_BANK];
 371         int ret;
 372
 373         bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
 374
 375         memcpy(reg_val, chip->reg_output, NBANK(chip));
 376         mutex_lock(&chip->i2c_lock);
 377         for (bank = 0; bank < NBANK(chip); bank++) {
 378                 bank_mask = mask[bank / sizeof(*mask)] >>
 379                            ((bank % sizeof(*mask)) * 8);
 380                 if (bank_mask) {
 381                         bank_val = bits[bank / sizeof(*bits)] >>
 382                                   ((bank % sizeof(*bits)) * 8);
 383                         reg_val[bank] = (reg_val[bank] & ~bank_mask) | bank_val;
 384                 }
 385         }
 386
 387         ret = i2c_smbus_write_i2c_block_data(chip->client,
 388                                              chip->regs->output << bank_shift,
 389                                              NBANK(chip), reg_val);
 390         if (ret)
 391                 goto exit;
 392
 393         memcpy(chip->reg_output, reg_val, NBANK(chip));
 394 exit:
 395         mutex_unlock(&chip->i2c_lock);
 396 }
 397
 398 static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios)
 399 {
 400         struct gpio_chip *gc;
 401
 402         gc = &chip->gpio_chip;
 403
 404         gc->direction_input  = pca953x_gpio_direction_input;
 405         gc->direction_output = pca953x_gpio_direction_output;
 406         gc->get = pca953x_gpio_get_value;
 407         gc->set = pca953x_gpio_set_value;
 408         gc->set_multiple = pca953x_gpio_set_multiple;
 409         gc->can_sleep = true;
 410
 411         gc->base = chip->gpio_start;
 412         gc->ngpio = gpios;
 413         gc->label = chip->client->name;
 414         gc->parent = &chip->client->dev;
 415         gc->owner = THIS_MODULE;
 416         gc->names = chip->names;
 417 }
 418
 419 #ifdef CONFIG_GPIO_PCA953X_IRQ
 420 static void pca953x_irq_mask(struct irq_data *d)
 421 {
 422         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 423         struct pca953x_chip *chip = gpiochip_get_data(gc);
 424
 425         chip->irq_mask[d->hwirq / BANK_SZ] &= ~(1 << (d->hwirq % BANK_SZ));
 426 }
 427
 428 static void pca953x_irq_unmask(struct irq_data *d)
 429 {
 430         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 431         struct pca953x_chip *chip = gpiochip_get_data(gc);
 432
 433         chip->irq_mask[d->hwirq / BANK_SZ] |= 1 << (d->hwirq % BANK_SZ);
 434 }
 435
 436 static void pca953x_irq_bus_lock(struct irq_data *d)
 437 {
 438         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 439         struct pca953x_chip *chip = gpiochip_get_data(gc);
 440
 441         mutex_lock(&chip->irq_lock);
 442 }
 443
 444 static void pca953x_irq_bus_sync_unlock(struct irq_data *d)
 445 {
 446         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 447         struct pca953x_chip *chip = gpiochip_get_data(gc);
 448         u8 new_irqs;
 449         int level, i;
 450         u8 invert_irq_mask[MAX_BANK];
 451
 452         if (chip->driver_data & PCA_PCAL) {
 453                 /* Enable latch on interrupt-enabled inputs */
 454                 pca953x_write_regs(chip, PCAL953X_IN_LATCH, chip->irq_mask);
 455
 456                 for (i = 0; i < NBANK(chip); i++)
 457                         invert_irq_mask[i] = ~chip->irq_mask[i];
 458
 459                 /* Unmask enabled interrupts */
 460                 pca953x_write_regs(chip, PCAL953X_INT_MASK, invert_irq_mask);
 461         }
 462
 463         /* Look for any newly setup interrupt */
 464         for (i = 0; i < NBANK(chip); i++) {
 465                 new_irqs = chip->irq_trig_fall[i] | chip->irq_trig_raise[i];
 466                 new_irqs &= ~chip->reg_direction[i];
 467
 468                 while (new_irqs) {
 469                         level = __ffs(new_irqs);
 470                         pca953x_gpio_direction_input(&chip->gpio_chip,
 471                                                         level + (BANK_SZ * i));
 472                         new_irqs &= ~(1 << level);
 473                 }
 474         }
 475
 476         mutex_unlock(&chip->irq_lock);
 477 }
 478
 479 static int pca953x_irq_set_type(struct irq_data *d, unsigned int type)
 480 {
 481         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 482         struct pca953x_chip *chip = gpiochip_get_data(gc);
 483         int bank_nb = d->hwirq / BANK_SZ;
 484         u8 mask = 1 << (d->hwirq % BANK_SZ);
 485
 486         if (!(type & IRQ_TYPE_EDGE_BOTH)) {
 487                 dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
 488                         d->irq, type);
 489                 return -EINVAL;
 490         }
 491
 492         if (type & IRQ_TYPE_EDGE_FALLING)
 493                 chip->irq_trig_fall[bank_nb] |= mask;
 494         else
 495                 chip->irq_trig_fall[bank_nb] &= ~mask;
 496
 497         if (type & IRQ_TYPE_EDGE_RISING)
 498                 chip->irq_trig_raise[bank_nb] |= mask;
 499         else
 500                 chip->irq_trig_raise[bank_nb] &= ~mask;
 501
 502         return 0;
 503 }
 504
 505 static struct irq_chip pca953x_irq_chip = {
 506         .name                   = "pca953x",
 507         .irq_mask               = pca953x_irq_mask,
 508         .irq_unmask             = pca953x_irq_unmask,
 509         .irq_bus_lock           = pca953x_irq_bus_lock,
 510         .irq_bus_sync_unlock    = pca953x_irq_bus_sync_unlock,
 511         .irq_set_type           = pca953x_irq_set_type,
 512 };
 513
 514 static bool pca953x_irq_pending(struct pca953x_chip *chip, u8 *pending)
 515 {
 516         u8 cur_stat[MAX_BANK];
 517         u8 old_stat[MAX_BANK];
 518         bool pending_seen = false;
 519         bool trigger_seen = false;
 520         u8 trigger[MAX_BANK];
 521         int ret, i;
 522
 523         if (chip->driver_data & PCA_PCAL) {
 524                 /* Read the current interrupt status from the device */
 525                 ret = pca953x_read_regs(chip, PCAL953X_INT_STAT, trigger);
 526                 if (ret)
 527                         return false;
 528
 529                 /* Check latched inputs and clear interrupt status */
 530                 ret = pca953x_read_regs(chip, PCA953X_INPUT, cur_stat);
 531                 if (ret)
 532                         return false;
 533
 534                 for (i = 0; i < NBANK(chip); i++) {
 535                         /* Apply filter for rising/falling edge selection */
 536                         pending[i] = (~cur_stat[i] & chip->irq_trig_fall[i]) |
 537                                 (cur_stat[i] & chip->irq_trig_raise[i]);
 538                         pending[i] &= trigger[i];
 539                         if (pending[i])
 540                                 pending_seen = true;
 541                 }
 542
 543                 return pending_seen;
 544         }
 545
 546         ret = pca953x_read_regs(chip, chip->regs->input, cur_stat);
 547         if (ret)
 548                 return false;
 549
 550         /* Remove output pins from the equation */
 551         for (i = 0; i < NBANK(chip); i++)
 552                 cur_stat[i] &= chip->reg_direction[i];
 553
 554         memcpy(old_stat, chip->irq_stat, NBANK(chip));
 555
 556         for (i = 0; i < NBANK(chip); i++) {
 557                 trigger[i] = (cur_stat[i] ^ old_stat[i]) & chip->irq_mask[i];
 558                 if (trigger[i])
 559                         trigger_seen = true;
 560         }
 561
 562         if (!trigger_seen)
 563                 return false;
 564
 565         memcpy(chip->irq_stat, cur_stat, NBANK(chip));
 566
 567         for (i = 0; i < NBANK(chip); i++) {
 568                 pending[i] = (old_stat[i] & chip->irq_trig_fall[i]) |
 569                         (cur_stat[i] & chip->irq_trig_raise[i]);
 570                 pending[i] &= trigger[i];
 571                 if (pending[i])
 572                         pending_seen = true;
 573         }
 574
 575         return pending_seen;
 576 }
 577
 578 static irqreturn_t pca953x_irq_handler(int irq, void *devid)
 579 {
 580         struct pca953x_chip *chip = devid;
 581         u8 pending[MAX_BANK];
 582         u8 level;
 583         unsigned nhandled = 0;
 584         int i;
 585
 586         if (!pca953x_irq_pending(chip, pending))
 587                 return IRQ_NONE;
 588
 589         for (i = 0; i < NBANK(chip); i++) {
 590                 while (pending[i]) {
 591                         level = __ffs(pending[i]);
 592                         handle_nested_irq(irq_find_mapping(chip->gpio_chip.irqdomain,
 593                                                         level + (BANK_SZ * i)));
 594                         pending[i] &= ~(1 << level);
 595                         nhandled++;
 596                 }
 597         }
 598
 599         return (nhandled > 0) ? IRQ_HANDLED : IRQ_NONE;
 600 }
 601
 602 static int pca953x_irq_setup(struct pca953x_chip *chip,
 603                              int irq_base)
 604 {
 605         struct i2c_client *client = chip->client;
 606         int ret, i;
 607
 608         if (client->irq && irq_base != -1
 609                         && (chip->driver_data & PCA_INT)) {
 610
 611                 ret = pca953x_read_regs(chip,
 612                                         chip->regs->input, chip->irq_stat);
 613                 if (ret)
 614                         return ret;
 615
 616                 /*
 617                  * There is no way to know which GPIO line generated the
 618                  * interrupt.  We have to rely on the previous read for
 619                  * this purpose.
 620                  */
 621                 for (i = 0; i < NBANK(chip); i++)
 622                         chip->irq_stat[i] &= chip->reg_direction[i];
 623                 mutex_init(&chip->irq_lock);
 624
 625                 ret = devm_request_threaded_irq(&client->dev,
 626                                         client->irq,
 627                                            NULL,
 628                                            pca953x_irq_handler,
 629                                            IRQF_TRIGGER_LOW | IRQF_ONESHOT |
 630                                                    IRQF_SHARED,
 631                                            dev_name(&client->dev), chip);
 632                 if (ret) {
 633                         dev_err(&client->dev, "failed to request irq %d\n",
 634                                 client->irq);
 635                         return ret;
 636                 }
 637
 638                 ret =  gpiochip_irqchip_add(&chip->gpio_chip,
 639                                             &pca953x_irq_chip,
 640                                             irq_base,
 641                                             handle_simple_irq,
 642                                             IRQ_TYPE_NONE);
 643                 if (ret) {
 644                         dev_err(&client->dev,
 645                                 "could not connect irqchip to gpiochip\n");
 646                         return ret;
 647                 }
 648
 649                 gpiochip_set_chained_irqchip(&chip->gpio_chip,
 650                                              &pca953x_irq_chip,
 651                                              client->irq, NULL);
 652         }
 653
 654         return 0;
 655 }
 656
 657 #else /* CONFIG_GPIO_PCA953X_IRQ */
 658 static int pca953x_irq_setup(struct pca953x_chip *chip,
 659                              int irq_base)
 660 {
 661         struct i2c_client *client = chip->client;
 662
 663         if (irq_base != -1 && (chip->driver_data & PCA_INT))
 664                 dev_warn(&client->dev, "interrupt support not compiled in\n");
 665
 666         return 0;
 667 }
 668 #endif
 669
 670 static int device_pca953x_init(struct pca953x_chip *chip, u32 invert)
 671 {
 672         int ret;
 673         u8 val[MAX_BANK];
 674
 675         chip->regs = &pca953x_regs;
 676
 677         ret = pca953x_read_regs(chip, chip->regs->output, chip->reg_output);
 678         if (ret)
 679                 goto out;
 680
 681         ret = pca953x_read_regs(chip, chip->regs->direction,
 682                                 chip->reg_direction);
 683         if (ret)
 684                 goto out;
 685
 686         /* set platform specific polarity inversion */
 687         if (invert)
 688                 memset(val, 0xFF, NBANK(chip));
 689         else
 690                 memset(val, 0, NBANK(chip));
 691
 692         ret = pca953x_write_regs(chip, PCA953X_INVERT, val);
 693 out:
 694         return ret;
 695 }
 696
 697 static int device_pca957x_init(struct pca953x_chip *chip, u32 invert)
 698 {
 699         int ret;
 700         u8 val[MAX_BANK];
 701
 702         chip->regs = &pca957x_regs;
 703
 704         ret = pca953x_read_regs(chip, chip->regs->output, chip->reg_output);
 705         if (ret)
 706                 goto out;
 707         ret = pca953x_read_regs(chip, chip->regs->direction,
 708                                 chip->reg_direction);
 709         if (ret)
 710                 goto out;
 711
 712         /* set platform specific polarity inversion */
 713         if (invert)
 714                 memset(val, 0xFF, NBANK(chip));
 715         else
 716                 memset(val, 0, NBANK(chip));
 717         ret = pca953x_write_regs(chip, PCA957X_INVRT, val);
 718         if (ret)
 719                 goto out;
 720
 721         /* To enable register 6, 7 to control pull up and pull down */
 722         memset(val, 0x02, NBANK(chip));
 723         ret = pca953x_write_regs(chip, PCA957X_BKEN, val);
 724         if (ret)
 725                 goto out;
 726
 727         return 0;
 728 out:
 729         return ret;
 730 }
 731
 732 static const struct of_device_id pca953x_dt_ids[];
 733
 734 static int pca953x_probe(struct i2c_client *client,
 735                                    const struct i2c_device_id *i2c_id)
 736 {
 737         struct pca953x_platform_data *pdata;
 738         struct pca953x_chip *chip;
 739         int irq_base = 0;
 740         int ret;
 741         u32 invert = 0;
 742         struct regulator *reg;
 743
 744         chip = devm_kzalloc(&client->dev,
 745                         sizeof(struct pca953x_chip), GFP_KERNEL);
 746         if (chip == NULL)
 747                 return -ENOMEM;
 748
 749         pdata = dev_get_platdata(&client->dev);
 750         if (pdata) {
 751                 irq_base = pdata->irq_base;
 752                 chip->gpio_start = pdata->gpio_base;
 753                 invert = pdata->invert;
 754                 chip->names = pdata->names;
 755         } else {
 756                 chip->gpio_start = -1;
 757                 irq_base = 0;
 758         }
 759
 760         chip->client = client;
 761
 762         reg = devm_regulator_get(&client->dev, "vcc");
 763         if (IS_ERR(reg)) {
 764                 ret = PTR_ERR(reg);
 765                 if (ret != -EPROBE_DEFER)
 766                         dev_err(&client->dev, "reg get err: %d\n", ret);
 767                 return ret;
 768         }
 769         ret = regulator_enable(reg);
 770         if (ret) {
 771                 dev_err(&client->dev, "reg en err: %d\n", ret);
 772                 return ret;
 773         }
 774         chip->regulator = reg;
 775
 776         if (i2c_id) {
 777                 chip->driver_data = i2c_id->driver_data;
 778         } else {
 779                 const struct acpi_device_id *acpi_id;
 780                 const struct of_device_id *match;
 781
 782                 match = of_match_device(pca953x_dt_ids, &client->dev);
 783                 if (match) {
 784                         chip->driver_data = (int)(uintptr_t)match->data;
 785                 } else {
 786                         acpi_id = acpi_match_device(pca953x_acpi_ids, &client->dev);
 787                         if (!acpi_id) {
 788                                 ret = -ENODEV;
 789                                 goto err_exit;
 790                         }
 791
 792                         chip->driver_data = acpi_id->driver_data;
 793                 }
 794         }
 795
 796         mutex_init(&chip->i2c_lock);
 797         /*
 798          * In case we have an i2c-mux controlled by a GPIO provided by an
 799          * expander using the same driver higher on the device tree, read the
 800          * i2c adapter nesting depth and use the retrieved value as lockdep
 801          * subclass for chip->i2c_lock.
 802          *
 803          * REVISIT: This solution is not complete. It protects us from lockdep
 804          * false positives when the expander controlling the i2c-mux is on
 805          * a different level on the device tree, but not when it's on the same
 806          * level on a different branch (in which case the subclass number
 807          * would be the same).
 808          *
 809          * TODO: Once a correct solution is developed, a similar fix should be
 810          * applied to all other i2c-controlled GPIO expanders (and potentially
 811          * regmap-i2c).
 812          */
 813         lockdep_set_subclass(&chip->i2c_lock,
 814                              i2c_adapter_depth(client->adapter));
 815
 816         /* initialize cached registers from their original values.
 817          * we can't share this chip with another i2c master.
 818          */
 819         pca953x_setup_gpio(chip, chip->driver_data & PCA_GPIO_MASK);
 820
 821         if (chip->gpio_chip.ngpio <= 8) {
 822                 chip->write_regs = pca953x_write_regs_8;
 823                 chip->read_regs = pca953x_read_regs_8;
 824         } else if (chip->gpio_chip.ngpio >= 24) {
 825                 chip->write_regs = pca953x_write_regs_24;
 826                 chip->read_regs = pca953x_read_regs_24;
 827         } else {
 828                 if (PCA_CHIP_TYPE(chip->driver_data) == PCA953X_TYPE)
 829                         chip->write_regs = pca953x_write_regs_16;
 830                 else
 831                         chip->write_regs = pca957x_write_regs_16;
 832                 chip->read_regs = pca953x_read_regs_16;
 833         }
 834
 835         if (PCA_CHIP_TYPE(chip->driver_data) == PCA953X_TYPE)
 836                 ret = device_pca953x_init(chip, invert);
 837         else
 838                 ret = device_pca957x_init(chip, invert);
 839         if (ret)
 840                 goto err_exit;
 841
 842         ret = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip);
 843         if (ret)
 844                 goto err_exit;
 845
 846         ret = pca953x_irq_setup(chip, irq_base);
 847         if (ret)
 848                 goto err_exit;
 849
 850         if (pdata && pdata->setup) {
 851                 ret = pdata->setup(client, chip->gpio_chip.base,
 852                                 chip->gpio_chip.ngpio, pdata->context);
 853                 if (ret < 0)
 854                         dev_warn(&client->dev, "setup failed, %d\n", ret);
 855         }
 856
 857         i2c_set_clientdata(client, chip);
 858         return 0;
 859
 860 err_exit:
 861         regulator_disable(chip->regulator);
 862         return ret;
 863 }
 864
 865 static int pca953x_remove(struct i2c_client *client)
 866 {
 867         struct pca953x_platform_data *pdata = dev_get_platdata(&client->dev);
 868         struct pca953x_chip *chip = i2c_get_clientdata(client);
 869         int ret;
 870
 871         if (pdata && pdata->teardown) {
 872                 ret = pdata->teardown(client, chip->gpio_chip.base,
 873                                 chip->gpio_chip.ngpio, pdata->context);
 874                 if (ret < 0)
 875                         dev_err(&client->dev, "%s failed, %d\n",
 876                                         "teardown", ret);
 877         } else {
 878                 ret = 0;
 879         }
 880
 881         regulator_disable(chip->regulator);
 882
 883         return ret;
 884 }
 885
 886 /* convenience to stop overlong match-table lines */
 887 #define OF_953X(__nrgpio, __int) (void *)(__nrgpio | PCA953X_TYPE | __int)
 888 #define OF_957X(__nrgpio, __int) (void *)(__nrgpio | PCA957X_TYPE | __int)
 889
 890 static const struct of_device_id pca953x_dt_ids[] = {
 891         { .compatible = "nxp,pca9505", .data = OF_953X(40, PCA_INT), },
 892         { .compatible = "nxp,pca9534", .data = OF_953X( 8, PCA_INT), },
 893         { .compatible = "nxp,pca9535", .data = OF_953X(16, PCA_INT), },
 894         { .compatible = "nxp,pca9536", .data = OF_953X( 4, 0), },
 895         { .compatible = "nxp,pca9537", .data = OF_953X( 4, PCA_INT), },
 896         { .compatible = "nxp,pca9538", .data = OF_953X( 8, PCA_INT), },
 897         { .compatible = "nxp,pca9539", .data = OF_953X(16, PCA_INT), },
 898         { .compatible = "nxp,pca9554", .data = OF_953X( 8, PCA_INT), },
 899         { .compatible = "nxp,pca9555", .data = OF_953X(16, PCA_INT), },
 900         { .compatible = "nxp,pca9556", .data = OF_953X( 8, 0), },
 901         { .compatible = "nxp,pca9557", .data = OF_953X( 8, 0), },
 902         { .compatible = "nxp,pca9574", .data = OF_957X( 8, PCA_INT), },
 903         { .compatible = "nxp,pca9575", .data = OF_957X(16, PCA_INT), },
 904         { .compatible = "nxp,pca9698", .data = OF_953X(40, 0), },
 905
 906         { .compatible = "maxim,max7310", .data = OF_953X( 8, 0), },
 907         { .compatible = "maxim,max7312", .data = OF_953X(16, PCA_INT), },
 908         { .compatible = "maxim,max7313", .data = OF_953X(16, PCA_INT), },
 909         { .compatible = "maxim,max7315", .data = OF_953X( 8, PCA_INT), },
 910
 911         { .compatible = "ti,pca6107", .data = OF_953X( 8, PCA_INT), },
 912         { .compatible = "ti,pca9536", .data = OF_953X( 4, 0), },
 913         { .compatible = "ti,tca6408", .data = OF_953X( 8, PCA_INT), },
 914         { .compatible = "ti,tca6416", .data = OF_953X(16, PCA_INT), },
 915         { .compatible = "ti,tca6424", .data = OF_953X(24, PCA_INT), },
 916
 917         { .compatible = "onsemi,pca9654", .data = OF_953X( 8, PCA_INT), },
 918
 919         { .compatible = "exar,xra1202", .data = OF_953X( 8, 0), },
 920         { }
 921 };
 922
 923 MODULE_DEVICE_TABLE(of, pca953x_dt_ids);
 924
 925 static struct i2c_driver pca953x_driver = {
 926         .driver = {
 927                 .name   = "pca953x",
 928                 .of_match_table = pca953x_dt_ids,
 929                 .acpi_match_table = ACPI_PTR(pca953x_acpi_ids),
 930         },
 931         .probe          = pca953x_probe,
 932         .remove         = pca953x_remove,
 933         .id_table       = pca953x_id,
 934 };
 935
 936 static int __init pca953x_init(void)
 937 {
 938         return i2c_add_driver(&pca953x_driver);
 939 }
 940 /* register after i2c postcore initcall and before
 941  * subsys initcalls that may rely on these GPIOs
 942  */
 943 subsys_initcall(pca953x_init);
 944
 945 static void __exit pca953x_exit(void)
 946 {
 947         i2c_del_driver(&pca953x_driver);
 948 }
 949 module_exit(pca953x_exit);
 950
 951 MODULE_AUTHOR("eric miao <eric.miao@marvell.com>");
 952 MODULE_DESCRIPTION("GPIO expander driver for PCA953x");
 953 MODULE_LICENSE("GPL");