drivers/gpio/gpio-sx150x.c

   1 /* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License version 2 and
   5  * only version 2 as published by the Free Software Foundation.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  *
  12  * You should have received a copy of the GNU General Public License
  13  * along with this program; if not, write to the Free Software
  14  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  15  * 02110-1301, USA.
  16  */
  17 #include <linux/gpio.h>
  18 #include <linux/i2c.h>
  19 #include <linux/init.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/irq.h>
  22 #include <linux/module.h>
  23 #include <linux/mutex.h>
  24 #include <linux/slab.h>
  25 #include <linux/i2c/sx150x.h>
  26 #include <linux/of.h>
  27 #include <linux/of_address.h>
  28 #include <linux/of_irq.h>
  29 #include <linux/of_gpio.h>
  30 #include <linux/of_device.h>
  31
  32 #define NO_UPDATE_PENDING       -1
  33
  34 /* The chip models of sx150x */
  35 #define SX150X_123 0
  36 #define SX150X_456 1
  37 #define SX150X_789 2
  38
  39 struct sx150x_123_pri {
  40         u8 reg_pld_mode;
  41         u8 reg_pld_table0;
  42         u8 reg_pld_table1;
  43         u8 reg_pld_table2;
  44         u8 reg_pld_table3;
  45         u8 reg_pld_table4;
  46         u8 reg_advance;
  47 };
  48
  49 struct sx150x_456_pri {
  50         u8 reg_pld_mode;
  51         u8 reg_pld_table0;
  52         u8 reg_pld_table1;
  53         u8 reg_pld_table2;
  54         u8 reg_pld_table3;
  55         u8 reg_pld_table4;
  56         u8 reg_advance;
  57 };
  58
  59 struct sx150x_789_pri {
  60         u8 reg_drain;
  61         u8 reg_polarity;
  62         u8 reg_clock;
  63         u8 reg_misc;
  64         u8 reg_reset;
  65         u8 ngpios;
  66 };
  67
  68 struct sx150x_device_data {
  69         u8 model;
  70         u8 reg_pullup;
  71         u8 reg_pulldn;
  72         u8 reg_dir;
  73         u8 reg_data;
  74         u8 reg_irq_mask;
  75         u8 reg_irq_src;
  76         u8 reg_sense;
  77         u8 ngpios;
  78         union {
  79                 struct sx150x_123_pri x123;
  80                 struct sx150x_456_pri x456;
  81                 struct sx150x_789_pri x789;
  82         } pri;
  83 };
  84
  85 struct sx150x_chip {
  86         struct gpio_chip                 gpio_chip;
  87         struct i2c_client               *client;
  88         const struct sx150x_device_data *dev_cfg;
  89         int                              irq_summary;
  90         int                              irq_base;
  91         int                              irq_update;
  92         u32                              irq_sense;
  93         u32                              irq_masked;
  94         u32                              dev_sense;
  95         u32                              dev_masked;
  96         struct irq_chip                  irq_chip;
  97         struct mutex                     lock;
  98 };
  99
 100 static const struct sx150x_device_data sx150x_devices[] = {
 101         [0] = { /* sx1508q */
 102                 .model = SX150X_789,
 103                 .reg_pullup     = 0x03,
 104                 .reg_pulldn     = 0x04,
 105                 .reg_dir        = 0x07,
 106                 .reg_data       = 0x08,
 107                 .reg_irq_mask   = 0x09,
 108                 .reg_irq_src    = 0x0c,
 109                 .reg_sense      = 0x0b,
 110                 .pri.x789 = {
 111                         .reg_drain      = 0x05,
 112                         .reg_polarity   = 0x06,
 113                         .reg_clock      = 0x0f,
 114                         .reg_misc       = 0x10,
 115                         .reg_reset      = 0x7d,
 116                 },
 117                 .ngpios = 8,
 118         },
 119         [1] = { /* sx1509q */
 120                 .model = SX150X_789,
 121                 .reg_pullup     = 0x07,
 122                 .reg_pulldn     = 0x09,
 123                 .reg_dir        = 0x0f,
 124                 .reg_data       = 0x11,
 125                 .reg_irq_mask   = 0x13,
 126                 .reg_irq_src    = 0x19,
 127                 .reg_sense      = 0x17,
 128                 .pri.x789 = {
 129                         .reg_drain      = 0x0b,
 130                         .reg_polarity   = 0x0d,
 131                         .reg_clock      = 0x1e,
 132                         .reg_misc       = 0x1f,
 133                         .reg_reset      = 0x7d,
 134                 },
 135                 .ngpios = 16
 136         },
 137         [2] = { /* sx1506q */
 138                 .model = SX150X_456,
 139                 .reg_pullup     = 0x05,
 140                 .reg_pulldn     = 0x07,
 141                 .reg_dir        = 0x03,
 142                 .reg_data       = 0x01,
 143                 .reg_irq_mask   = 0x09,
 144                 .reg_irq_src    = 0x0f,
 145                 .reg_sense      = 0x0d,
 146                 .pri.x456 = {
 147                         .reg_pld_mode   = 0x21,
 148                         .reg_pld_table0 = 0x23,
 149                         .reg_pld_table1 = 0x25,
 150                         .reg_pld_table2 = 0x27,
 151                         .reg_pld_table3 = 0x29,
 152                         .reg_pld_table4 = 0x2b,
 153                         .reg_advance    = 0xad,
 154                 },
 155                 .ngpios = 16
 156         },
 157         [3] = { /* sx1502q */
 158                 .model = SX150X_123,
 159                 .reg_pullup     = 0x02,
 160                 .reg_pulldn     = 0x03,
 161                 .reg_dir        = 0x01,
 162                 .reg_data       = 0x00,
 163                 .reg_irq_mask   = 0x05,
 164                 .reg_irq_src    = 0x08,
 165                 .reg_sense      = 0x07,
 166                 .pri.x123 = {
 167                         .reg_pld_mode   = 0x10,
 168                         .reg_pld_table0 = 0x11,
 169                         .reg_pld_table1 = 0x12,
 170                         .reg_pld_table2 = 0x13,
 171                         .reg_pld_table3 = 0x14,
 172                         .reg_pld_table4 = 0x15,
 173                         .reg_advance    = 0xad,
 174                 },
 175                 .ngpios = 8,
 176         },
 177 };
 178
 179 static const struct i2c_device_id sx150x_id[] = {
 180         {"sx1508q", 0},
 181         {"sx1509q", 1},
 182         {"sx1506q", 2},
 183         {"sx1502q", 3},
 184         {}
 185 };
 186 MODULE_DEVICE_TABLE(i2c, sx150x_id);
 187
 188 static const struct of_device_id sx150x_of_match[] = {
 189         { .compatible = "semtech,sx1508q" },
 190         { .compatible = "semtech,sx1509q" },
 191         { .compatible = "semtech,sx1506q" },
 192         { .compatible = "semtech,sx1502q" },
 193         {},
 194 };
 195 MODULE_DEVICE_TABLE(of, sx150x_of_match);
 196
 197 struct sx150x_chip *to_sx150x(struct gpio_chip *gc)
 198 {
 199         return container_of(gc, struct sx150x_chip, gpio_chip);
 200 }
 201
 202 static s32 sx150x_i2c_write(struct i2c_client *client, u8 reg, u8 val)
 203 {
 204         s32 err = i2c_smbus_write_byte_data(client, reg, val);
 205
 206         if (err < 0)
 207                 dev_warn(&client->dev,
 208                         "i2c write fail: can't write %02x to %02x: %d\n",
 209                         val, reg, err);
 210         return err;
 211 }
 212
 213 static s32 sx150x_i2c_read(struct i2c_client *client, u8 reg, u8 *val)
 214 {
 215         s32 err = i2c_smbus_read_byte_data(client, reg);
 216
 217         if (err >= 0)
 218                 *val = err;
 219         else
 220                 dev_warn(&client->dev,
 221                         "i2c read fail: can't read from %02x: %d\n",
 222                         reg, err);
 223         return err;
 224 }
 225
 226 static inline bool offset_is_oscio(struct sx150x_chip *chip, unsigned offset)
 227 {
 228         return (chip->dev_cfg->ngpios == offset);
 229 }
 230
 231 /*
 232  * These utility functions solve the common problem of locating and setting
 233  * configuration bits.  Configuration bits are grouped into registers
 234  * whose indexes increase downwards.  For example, with eight-bit registers,
 235  * sixteen gpios would have their config bits grouped in the following order:
 236  * REGISTER N-1 [ f e d c b a 9 8 ]
 237  *          N   [ 7 6 5 4 3 2 1 0 ]
 238  *
 239  * For multi-bit configurations, the pattern gets wider:
 240  * REGISTER N-3 [ f f e e d d c c ]
 241  *          N-2 [ b b a a 9 9 8 8 ]
 242  *          N-1 [ 7 7 6 6 5 5 4 4 ]
 243  *          N   [ 3 3 2 2 1 1 0 0 ]
 244  *
 245  * Given the address of the starting register 'N', the index of the gpio
 246  * whose configuration we seek to change, and the width in bits of that
 247  * configuration, these functions allow us to locate the correct
 248  * register and mask the correct bits.
 249  */
 250 static inline void sx150x_find_cfg(u8 offset, u8 width,
 251                                 u8 *reg, u8 *mask, u8 *shift)
 252 {
 253         *reg   -= offset * width / 8;
 254         *mask   = (1 << width) - 1;
 255         *shift  = (offset * width) % 8;
 256         *mask <<= *shift;
 257 }
 258
 259 static s32 sx150x_write_cfg(struct sx150x_chip *chip,
 260                         u8 offset, u8 width, u8 reg, u8 val)
 261 {
 262         u8  mask;
 263         u8  data;
 264         u8  shift;
 265         s32 err;
 266
 267         sx150x_find_cfg(offset, width, &reg, &mask, &shift);
 268         err = sx150x_i2c_read(chip->client, reg, &data);
 269         if (err < 0)
 270                 return err;
 271
 272         data &= ~mask;
 273         data |= (val << shift) & mask;
 274         return sx150x_i2c_write(chip->client, reg, data);
 275 }
 276
 277 static int sx150x_get_io(struct sx150x_chip *chip, unsigned offset)
 278 {
 279         u8  reg = chip->dev_cfg->reg_data;
 280         u8  mask;
 281         u8  data;
 282         u8  shift;
 283         s32 err;
 284
 285         sx150x_find_cfg(offset, 1, &reg, &mask, &shift);
 286         err = sx150x_i2c_read(chip->client, reg, &data);
 287         if (err >= 0)
 288                 err = (data & mask) != 0 ? 1 : 0;
 289
 290         return err;
 291 }
 292
 293 static void sx150x_set_oscio(struct sx150x_chip *chip, int val)
 294 {
 295         sx150x_i2c_write(chip->client,
 296                         chip->dev_cfg->pri.x789.reg_clock,
 297                         (val ? 0x1f : 0x10));
 298 }
 299
 300 static void sx150x_set_io(struct sx150x_chip *chip, unsigned offset, int val)
 301 {
 302         sx150x_write_cfg(chip,
 303                         offset,
 304                         1,
 305                         chip->dev_cfg->reg_data,
 306                         (val ? 1 : 0));
 307 }
 308
 309 static int sx150x_io_input(struct sx150x_chip *chip, unsigned offset)
 310 {
 311         return sx150x_write_cfg(chip,
 312                                 offset,
 313                                 1,
 314                                 chip->dev_cfg->reg_dir,
 315                                 1);
 316 }
 317
 318 static int sx150x_io_output(struct sx150x_chip *chip, unsigned offset, int val)
 319 {
 320         int err;
 321
 322         err = sx150x_write_cfg(chip,
 323                         offset,
 324                         1,
 325                         chip->dev_cfg->reg_data,
 326                         (val ? 1 : 0));
 327         if (err >= 0)
 328                 err = sx150x_write_cfg(chip,
 329                                 offset,
 330                                 1,
 331                                 chip->dev_cfg->reg_dir,
 332                                 0);
 333         return err;
 334 }
 335
 336 static int sx150x_gpio_get(struct gpio_chip *gc, unsigned offset)
 337 {
 338         struct sx150x_chip *chip = to_sx150x(gc);
 339         int status = -EINVAL;
 340
 341         if (!offset_is_oscio(chip, offset)) {
 342                 mutex_lock(&chip->lock);
 343                 status = sx150x_get_io(chip, offset);
 344                 mutex_unlock(&chip->lock);
 345         }
 346
 347         return status;
 348 }
 349
 350 static void sx150x_gpio_set(struct gpio_chip *gc, unsigned offset, int val)
 351 {
 352         struct sx150x_chip *chip = to_sx150x(gc);
 353
 354         mutex_lock(&chip->lock);
 355         if (offset_is_oscio(chip, offset))
 356                 sx150x_set_oscio(chip, val);
 357         else
 358                 sx150x_set_io(chip, offset, val);
 359         mutex_unlock(&chip->lock);
 360 }
 361
 362 static int sx150x_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
 363 {
 364         struct sx150x_chip *chip = to_sx150x(gc);
 365         int status = -EINVAL;
 366
 367         if (!offset_is_oscio(chip, offset)) {
 368                 mutex_lock(&chip->lock);
 369                 status = sx150x_io_input(chip, offset);
 370                 mutex_unlock(&chip->lock);
 371         }
 372         return status;
 373 }
 374
 375 static int sx150x_gpio_direction_output(struct gpio_chip *gc,
 376                                         unsigned offset,
 377                                         int val)
 378 {
 379         struct sx150x_chip *chip = to_sx150x(gc);
 380         int status = 0;
 381
 382         if (!offset_is_oscio(chip, offset)) {
 383                 mutex_lock(&chip->lock);
 384                 status = sx150x_io_output(chip, offset, val);
 385                 mutex_unlock(&chip->lock);
 386         }
 387         return status;
 388 }
 389
 390 static void sx150x_irq_mask(struct irq_data *d)
 391 {
 392         struct sx150x_chip *chip = to_sx150x(irq_data_get_irq_chip_data(d));
 393         unsigned n = d->hwirq;
 394
 395         chip->irq_masked |= (1 << n);
 396         chip->irq_update = n;
 397 }
 398
 399 static void sx150x_irq_unmask(struct irq_data *d)
 400 {
 401         struct sx150x_chip *chip = to_sx150x(irq_data_get_irq_chip_data(d));
 402         unsigned n = d->hwirq;
 403
 404         chip->irq_masked &= ~(1 << n);
 405         chip->irq_update = n;
 406 }
 407
 408 static int sx150x_irq_set_type(struct irq_data *d, unsigned int flow_type)
 409 {
 410         struct sx150x_chip *chip = to_sx150x(irq_data_get_irq_chip_data(d));
 411         unsigned n, val = 0;
 412
 413         if (flow_type & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
 414                 return -EINVAL;
 415
 416         n = d->hwirq;
 417
 418         if (flow_type & IRQ_TYPE_EDGE_RISING)
 419                 val |= 0x1;
 420         if (flow_type & IRQ_TYPE_EDGE_FALLING)
 421                 val |= 0x2;
 422
 423         chip->irq_sense &= ~(3UL << (n * 2));
 424         chip->irq_sense |= val << (n * 2);
 425         chip->irq_update = n;
 426         return 0;
 427 }
 428
 429 static irqreturn_t sx150x_irq_thread_fn(int irq, void *dev_id)
 430 {
 431         struct sx150x_chip *chip = (struct sx150x_chip *)dev_id;
 432         unsigned nhandled = 0;
 433         unsigned sub_irq;
 434         unsigned n;
 435         s32 err;
 436         u8 val;
 437         int i;
 438
 439         for (i = (chip->dev_cfg->ngpios / 8) - 1; i >= 0; --i) {
 440                 err = sx150x_i2c_read(chip->client,
 441                                       chip->dev_cfg->reg_irq_src - i,
 442                                       &val);
 443                 if (err < 0)
 444                         continue;
 445
 446                 sx150x_i2c_write(chip->client,
 447                                 chip->dev_cfg->reg_irq_src - i,
 448                                 val);
 449                 for (n = 0; n < 8; ++n) {
 450                         if (val & (1 << n)) {
 451                                 sub_irq = irq_find_mapping(
 452                                         chip->gpio_chip.irqdomain,
 453                                         (i * 8) + n);
 454                                 handle_nested_irq(sub_irq);
 455                                 ++nhandled;
 456                         }
 457                 }
 458         }
 459
 460         return (nhandled > 0 ? IRQ_HANDLED : IRQ_NONE);
 461 }
 462
 463 static void sx150x_irq_bus_lock(struct irq_data *d)
 464 {
 465         struct sx150x_chip *chip = to_sx150x(irq_data_get_irq_chip_data(d));
 466
 467         mutex_lock(&chip->lock);
 468 }
 469
 470 static void sx150x_irq_bus_sync_unlock(struct irq_data *d)
 471 {
 472         struct sx150x_chip *chip = to_sx150x(irq_data_get_irq_chip_data(d));
 473         unsigned n;
 474
 475         if (chip->irq_update == NO_UPDATE_PENDING)
 476                 goto out;
 477
 478         n = chip->irq_update;
 479         chip->irq_update = NO_UPDATE_PENDING;
 480
 481         /* Avoid updates if nothing changed */
 482         if (chip->dev_sense == chip->irq_sense &&
 483             chip->dev_masked == chip->irq_masked)
 484                 goto out;
 485
 486         chip->dev_sense = chip->irq_sense;
 487         chip->dev_masked = chip->irq_masked;
 488
 489         if (chip->irq_masked & (1 << n)) {
 490                 sx150x_write_cfg(chip, n, 1, chip->dev_cfg->reg_irq_mask, 1);
 491                 sx150x_write_cfg(chip, n, 2, chip->dev_cfg->reg_sense, 0);
 492         } else {
 493                 sx150x_write_cfg(chip, n, 1, chip->dev_cfg->reg_irq_mask, 0);
 494                 sx150x_write_cfg(chip, n, 2, chip->dev_cfg->reg_sense,
 495                                  chip->irq_sense >> (n * 2));
 496         }
 497 out:
 498         mutex_unlock(&chip->lock);
 499 }
 500
 501 static void sx150x_init_chip(struct sx150x_chip *chip,
 502                         struct i2c_client *client,
 503                         kernel_ulong_t driver_data,
 504                         struct sx150x_platform_data *pdata)
 505 {
 506         mutex_init(&chip->lock);
 507
 508         chip->client                     = client;
 509         chip->dev_cfg                    = &sx150x_devices[driver_data];
 510         chip->gpio_chip.parent              = &client->dev;
 511         chip->gpio_chip.label            = client->name;
 512         chip->gpio_chip.direction_input  = sx150x_gpio_direction_input;
 513         chip->gpio_chip.direction_output = sx150x_gpio_direction_output;
 514         chip->gpio_chip.get              = sx150x_gpio_get;
 515         chip->gpio_chip.set              = sx150x_gpio_set;
 516         chip->gpio_chip.base             = pdata->gpio_base;
 517         chip->gpio_chip.can_sleep        = true;
 518         chip->gpio_chip.ngpio            = chip->dev_cfg->ngpios;
 519 #ifdef CONFIG_OF_GPIO
 520         chip->gpio_chip.of_node          = client->dev.of_node;
 521         chip->gpio_chip.of_gpio_n_cells  = 2;
 522 #endif
 523         if (pdata->oscio_is_gpo)
 524                 ++chip->gpio_chip.ngpio;
 525
 526         chip->irq_chip.name                = client->name;
 527         chip->irq_chip.irq_mask            = sx150x_irq_mask;
 528         chip->irq_chip.irq_unmask          = sx150x_irq_unmask;
 529         chip->irq_chip.irq_set_type        = sx150x_irq_set_type;
 530         chip->irq_chip.irq_bus_lock        = sx150x_irq_bus_lock;
 531         chip->irq_chip.irq_bus_sync_unlock = sx150x_irq_bus_sync_unlock;
 532         chip->irq_summary                  = -1;
 533         chip->irq_base                     = -1;
 534         chip->irq_masked                   = ~0;
 535         chip->irq_sense                    = 0;
 536         chip->dev_masked                   = ~0;
 537         chip->dev_sense                    = 0;
 538         chip->irq_update                   = NO_UPDATE_PENDING;
 539 }
 540
 541 static int sx150x_init_io(struct sx150x_chip *chip, u8 base, u16 cfg)
 542 {
 543         int err = 0;
 544         unsigned n;
 545
 546         for (n = 0; err >= 0 && n < (chip->dev_cfg->ngpios / 8); ++n)
 547                 err = sx150x_i2c_write(chip->client, base - n, cfg >> (n * 8));
 548         return err;
 549 }
 550
 551 static int sx150x_reset(struct sx150x_chip *chip)
 552 {
 553         int err;
 554
 555         err = i2c_smbus_write_byte_data(chip->client,
 556                                         chip->dev_cfg->pri.x789.reg_reset,
 557                                         0x12);
 558         if (err < 0)
 559                 return err;
 560
 561         err = i2c_smbus_write_byte_data(chip->client,
 562                                         chip->dev_cfg->pri.x789.reg_reset,
 563                                         0x34);
 564         return err;
 565 }
 566
 567 static int sx150x_init_hw(struct sx150x_chip *chip,
 568                         struct sx150x_platform_data *pdata)
 569 {
 570         int err = 0;
 571
 572         if (pdata->reset_during_probe) {
 573                 err = sx150x_reset(chip);
 574                 if (err < 0)
 575                         return err;
 576         }
 577
 578         if (chip->dev_cfg->model == SX150X_789)
 579                 err = sx150x_i2c_write(chip->client,
 580                                 chip->dev_cfg->pri.x789.reg_misc,
 581                                 0x01);
 582         else if (chip->dev_cfg->model == SX150X_456)
 583                 err = sx150x_i2c_write(chip->client,
 584                                 chip->dev_cfg->pri.x456.reg_advance,
 585                                 0x04);
 586         else
 587                 err = sx150x_i2c_write(chip->client,
 588                                 chip->dev_cfg->pri.x123.reg_advance,
 589                                 0x00);
 590         if (err < 0)
 591                 return err;
 592
 593         err = sx150x_init_io(chip, chip->dev_cfg->reg_pullup,
 594                         pdata->io_pullup_ena);
 595         if (err < 0)
 596                 return err;
 597
 598         err = sx150x_init_io(chip, chip->dev_cfg->reg_pulldn,
 599                         pdata->io_pulldn_ena);
 600         if (err < 0)
 601                 return err;
 602
 603         if (chip->dev_cfg->model == SX150X_789) {
 604                 err = sx150x_init_io(chip,
 605                                 chip->dev_cfg->pri.x789.reg_drain,
 606                                 pdata->io_open_drain_ena);
 607                 if (err < 0)
 608                         return err;
 609
 610                 err = sx150x_init_io(chip,
 611                                 chip->dev_cfg->pri.x789.reg_polarity,
 612                                 pdata->io_polarity);
 613                 if (err < 0)
 614                         return err;
 615         } else if (chip->dev_cfg->model == SX150X_456) {
 616                 /* Set all pins to work in normal mode */
 617                 err = sx150x_init_io(chip,
 618                                 chip->dev_cfg->pri.x456.reg_pld_mode,
 619                                 0);
 620                 if (err < 0)
 621                         return err;
 622         } else {
 623                 /* Set all pins to work in normal mode */
 624                 err = sx150x_init_io(chip,
 625                                 chip->dev_cfg->pri.x123.reg_pld_mode,
 626                                 0);
 627                 if (err < 0)
 628                         return err;
 629         }
 630
 631
 632         if (pdata->oscio_is_gpo)
 633                 sx150x_set_oscio(chip, 0);
 634
 635         return err;
 636 }
 637
 638 static int sx150x_install_irq_chip(struct sx150x_chip *chip,
 639                                 int irq_summary,
 640                                 int irq_base)
 641 {
 642         int err;
 643
 644         chip->irq_summary = irq_summary;
 645         chip->irq_base    = irq_base;
 646
 647         /* Add gpio chip to irq subsystem */
 648         err = gpiochip_irqchip_add(&chip->gpio_chip,
 649                 &chip->irq_chip, chip->irq_base,
 650                 handle_edge_irq, IRQ_TYPE_EDGE_BOTH);
 651         if (err) {
 652                 dev_err(&chip->client->dev,
 653                         "could not connect irqchip to gpiochip\n");
 654                 return  err;
 655         }
 656
 657         err = devm_request_threaded_irq(&chip->client->dev,
 658                         irq_summary, NULL, sx150x_irq_thread_fn,
 659                         IRQF_ONESHOT | IRQF_SHARED | IRQF_TRIGGER_FALLING,
 660                         chip->irq_chip.name, chip);
 661         if (err < 0) {
 662                 chip->irq_summary = -1;
 663                 chip->irq_base    = -1;
 664         }
 665
 666         return err;
 667 }
 668
 669 static int sx150x_probe(struct i2c_client *client,
 670                                 const struct i2c_device_id *id)
 671 {
 672         static const u32 i2c_funcs = I2C_FUNC_SMBUS_BYTE_DATA |
 673                                      I2C_FUNC_SMBUS_WRITE_WORD_DATA;
 674         struct sx150x_platform_data *pdata;
 675         struct sx150x_chip *chip;
 676         int rc;
 677
 678         pdata = dev_get_platdata(&client->dev);
 679         if (!pdata)
 680                 return -EINVAL;
 681
 682         if (!i2c_check_functionality(client->adapter, i2c_funcs))
 683                 return -ENOSYS;
 684
 685         chip = devm_kzalloc(&client->dev,
 686                 sizeof(struct sx150x_chip), GFP_KERNEL);
 687         if (!chip)
 688                 return -ENOMEM;
 689
 690         sx150x_init_chip(chip, client, id->driver_data, pdata);
 691         rc = sx150x_init_hw(chip, pdata);
 692         if (rc < 0)
 693                 return rc;
 694
 695         rc = gpiochip_add(&chip->gpio_chip);
 696         if (rc)
 697                 return rc;
 698
 699         if (pdata->irq_summary >= 0) {
 700                 rc = sx150x_install_irq_chip(chip,
 701                                         pdata->irq_summary,
 702                                         pdata->irq_base);
 703                 if (rc < 0)
 704                         goto probe_fail_post_gpiochip_add;
 705         }
 706
 707         i2c_set_clientdata(client, chip);
 708
 709         return 0;
 710 probe_fail_post_gpiochip_add:
 711         gpiochip_remove(&chip->gpio_chip);
 712         return rc;
 713 }
 714
 715 static int sx150x_remove(struct i2c_client *client)
 716 {
 717         struct sx150x_chip *chip;
 718
 719         chip = i2c_get_clientdata(client);
 720         gpiochip_remove(&chip->gpio_chip);
 721
 722         return 0;
 723 }
 724
 725 static struct i2c_driver sx150x_driver = {
 726         .driver = {
 727                 .name = "sx150x",
 728                 .of_match_table = of_match_ptr(sx150x_of_match),
 729         },
 730         .probe    = sx150x_probe,
 731         .remove   = sx150x_remove,
 732         .id_table = sx150x_id,
 733 };
 734
 735 static int __init sx150x_init(void)
 736 {
 737         return i2c_add_driver(&sx150x_driver);
 738 }
 739 subsys_initcall(sx150x_init);
 740
 741 static void __exit sx150x_exit(void)
 742 {
 743         return i2c_del_driver(&sx150x_driver);
 744 }
 745 module_exit(sx150x_exit);
 746
 747 MODULE_AUTHOR("Gregory Bean <gbean@codeaurora.org>");
 748 MODULE_DESCRIPTION("Driver for Semtech SX150X I2C GPIO Expanders");
 749 MODULE_LICENSE("GPL v2");