drivers/gpio/gpio-sx150x.c

   1 /* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
   2  *
   3  * Driver for Semtech SX150X I2C GPIO Expanders
   4  *
   5  * Author: Gregory Bean <gbean@codeaurora.org>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 and
   9  * only version 2 as published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19  * 02110-1301, USA.
  20  */
  21 #include <linux/gpio.h>
  22 #include <linux/i2c.h>
  23 #include <linux/init.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/irq.h>
  26 #include <linux/mutex.h>
  27 #include <linux/slab.h>
  28 #include <linux/of.h>
  29 #include <linux/of_address.h>
  30 #include <linux/of_irq.h>
  31 #include <linux/of_gpio.h>
  32 #include <linux/of_device.h>
  33
  34 #define NO_UPDATE_PENDING       -1
  35
  36 /* The chip models of sx150x */
  37 #define SX150X_123 0
  38 #define SX150X_456 1
  39 #define SX150X_789 2
  40
  41 struct sx150x_123_pri {
  42         u8 reg_pld_mode;
  43         u8 reg_pld_table0;
  44         u8 reg_pld_table1;
  45         u8 reg_pld_table2;
  46         u8 reg_pld_table3;
  47         u8 reg_pld_table4;
  48         u8 reg_advance;
  49 };
  50
  51 struct sx150x_456_pri {
  52         u8 reg_pld_mode;
  53         u8 reg_pld_table0;
  54         u8 reg_pld_table1;
  55         u8 reg_pld_table2;
  56         u8 reg_pld_table3;
  57         u8 reg_pld_table4;
  58         u8 reg_advance;
  59 };
  60
  61 struct sx150x_789_pri {
  62         u8 reg_drain;
  63         u8 reg_polarity;
  64         u8 reg_clock;
  65         u8 reg_misc;
  66         u8 reg_reset;
  67         u8 ngpios;
  68 };
  69
  70 struct sx150x_device_data {
  71         u8 model;
  72         u8 reg_pullup;
  73         u8 reg_pulldn;
  74         u8 reg_dir;
  75         u8 reg_data;
  76         u8 reg_irq_mask;
  77         u8 reg_irq_src;
  78         u8 reg_sense;
  79         u8 ngpios;
  80         union {
  81                 struct sx150x_123_pri x123;
  82                 struct sx150x_456_pri x456;
  83                 struct sx150x_789_pri x789;
  84         } pri;
  85 };
  86
  87 /**
  88  * struct sx150x_platform_data - config data for SX150x driver
  89  * @gpio_base: The index number of the first GPIO assigned to this
  90  *             GPIO expander.  The expander will create a block of
  91  *             consecutively numbered gpios beginning at the given base,
  92  *             with the size of the block depending on the model of the
  93  *             expander chip.
  94  * @oscio_is_gpo: If set to true, the driver will configure OSCIO as a GPO
  95  *                instead of as an oscillator, increasing the size of the
  96  *                GP(I)O pool created by this expander by one.  The
  97  *                output-only GPO pin will be added at the end of the block.
  98  * @io_pullup_ena: A bit-mask which enables or disables the pull-up resistor
  99  *                 for each IO line in the expander.  Setting the bit at
 100  *                 position n will enable the pull-up for the IO at
 101  *                 the corresponding offset.  For chips with fewer than
 102  *                 16 IO pins, high-end bits are ignored.
 103  * @io_pulldn_ena: A bit-mask which enables-or disables the pull-down
 104  *                 resistor for each IO line in the expander. Setting the
 105  *                 bit at position n will enable the pull-down for the IO at
 106  *                 the corresponding offset.  For chips with fewer than
 107  *                 16 IO pins, high-end bits are ignored.
 108  * @io_polarity: A bit-mask which enables polarity inversion for each IO line
 109  *               in the expander.  Setting the bit at position n inverts
 110  *               the polarity of that IO line, while clearing it results
 111  *               in normal polarity. For chips with fewer than 16 IO pins,
 112  *               high-end bits are ignored.
 113  * @irq_summary: The 'summary IRQ' line to which the GPIO expander's INT line
 114  *               is connected, via which it reports interrupt events
 115  *               across all GPIO lines.  This must be a real,
 116  *               pre-existing IRQ line.
 117  *               Setting this value < 0 disables the irq_chip functionality
 118  *               of the driver.
 119  * @irq_base: The first 'virtual IRQ' line at which our block of GPIO-based
 120  *            IRQ lines will appear.  Similarly to gpio_base, the expander
 121  *            will create a block of irqs beginning at this number.
 122  *            This value is ignored if irq_summary is < 0.
 123  * @reset_during_probe: If set to true, the driver will trigger a full
 124  *                      reset of the chip at the beginning of the probe
 125  *                      in order to place it in a known state.
 126  */
 127 struct sx150x_platform_data {
 128         unsigned gpio_base;
 129         bool     oscio_is_gpo;
 130         u16      io_pullup_ena;
 131         u16      io_pulldn_ena;
 132         u16      io_polarity;
 133         int      irq_summary;
 134         unsigned irq_base;
 135         bool     reset_during_probe;
 136 };
 137
 138 struct sx150x_chip {
 139         struct gpio_chip                 gpio_chip;
 140         struct i2c_client               *client;
 141         const struct sx150x_device_data *dev_cfg;
 142         int                              irq_summary;
 143         int                              irq_base;
 144         int                              irq_update;
 145         u32                              irq_sense;
 146         u32                              irq_masked;
 147         u32                              dev_sense;
 148         u32                              dev_masked;
 149         struct irq_chip                  irq_chip;
 150         struct mutex                     lock;
 151 };
 152
 153 static const struct sx150x_device_data sx150x_devices[] = {
 154         [0] = { /* sx1508q */
 155                 .model = SX150X_789,
 156                 .reg_pullup     = 0x03,
 157                 .reg_pulldn     = 0x04,
 158                 .reg_dir        = 0x07,
 159                 .reg_data       = 0x08,
 160                 .reg_irq_mask   = 0x09,
 161                 .reg_irq_src    = 0x0c,
 162                 .reg_sense      = 0x0b,
 163                 .pri.x789 = {
 164                         .reg_drain      = 0x05,
 165                         .reg_polarity   = 0x06,
 166                         .reg_clock      = 0x0f,
 167                         .reg_misc       = 0x10,
 168                         .reg_reset      = 0x7d,
 169                 },
 170                 .ngpios = 8,
 171         },
 172         [1] = { /* sx1509q */
 173                 .model = SX150X_789,
 174                 .reg_pullup     = 0x07,
 175                 .reg_pulldn     = 0x09,
 176                 .reg_dir        = 0x0f,
 177                 .reg_data       = 0x11,
 178                 .reg_irq_mask   = 0x13,
 179                 .reg_irq_src    = 0x19,
 180                 .reg_sense      = 0x17,
 181                 .pri.x789 = {
 182                         .reg_drain      = 0x0b,
 183                         .reg_polarity   = 0x0d,
 184                         .reg_clock      = 0x1e,
 185                         .reg_misc       = 0x1f,
 186                         .reg_reset      = 0x7d,
 187                 },
 188                 .ngpios = 16
 189         },
 190         [2] = { /* sx1506q */
 191                 .model = SX150X_456,
 192                 .reg_pullup     = 0x05,
 193                 .reg_pulldn     = 0x07,
 194                 .reg_dir        = 0x03,
 195                 .reg_data       = 0x01,
 196                 .reg_irq_mask   = 0x09,
 197                 .reg_irq_src    = 0x0f,
 198                 .reg_sense      = 0x0d,
 199                 .pri.x456 = {
 200                         .reg_pld_mode   = 0x21,
 201                         .reg_pld_table0 = 0x23,
 202                         .reg_pld_table1 = 0x25,
 203                         .reg_pld_table2 = 0x27,
 204                         .reg_pld_table3 = 0x29,
 205                         .reg_pld_table4 = 0x2b,
 206                         .reg_advance    = 0xad,
 207                 },
 208                 .ngpios = 16
 209         },
 210         [3] = { /* sx1502q */
 211                 .model = SX150X_123,
 212                 .reg_pullup     = 0x02,
 213                 .reg_pulldn     = 0x03,
 214                 .reg_dir        = 0x01,
 215                 .reg_data       = 0x00,
 216                 .reg_irq_mask   = 0x05,
 217                 .reg_irq_src    = 0x08,
 218                 .reg_sense      = 0x07,
 219                 .pri.x123 = {
 220                         .reg_pld_mode   = 0x10,
 221                         .reg_pld_table0 = 0x11,
 222                         .reg_pld_table1 = 0x12,
 223                         .reg_pld_table2 = 0x13,
 224                         .reg_pld_table3 = 0x14,
 225                         .reg_pld_table4 = 0x15,
 226                         .reg_advance    = 0xad,
 227                 },
 228                 .ngpios = 8,
 229         },
 230 };
 231
 232 static const struct i2c_device_id sx150x_id[] = {
 233         {"sx1508q", 0},
 234         {"sx1509q", 1},
 235         {"sx1506q", 2},
 236         {"sx1502q", 3},
 237         {}
 238 };
 239
 240 static const struct of_device_id sx150x_of_match[] = {
 241         { .compatible = "semtech,sx1508q" },
 242         { .compatible = "semtech,sx1509q" },
 243         { .compatible = "semtech,sx1506q" },
 244         { .compatible = "semtech,sx1502q" },
 245         {},
 246 };
 247
 248 static s32 sx150x_i2c_write(struct i2c_client *client, u8 reg, u8 val)
 249 {
 250         s32 err = i2c_smbus_write_byte_data(client, reg, val);
 251
 252         if (err < 0)
 253                 dev_warn(&client->dev,
 254                         "i2c write fail: can't write %02x to %02x: %d\n",
 255                         val, reg, err);
 256         return err;
 257 }
 258
 259 static s32 sx150x_i2c_read(struct i2c_client *client, u8 reg, u8 *val)
 260 {
 261         s32 err = i2c_smbus_read_byte_data(client, reg);
 262
 263         if (err >= 0)
 264                 *val = err;
 265         else
 266                 dev_warn(&client->dev,
 267                         "i2c read fail: can't read from %02x: %d\n",
 268                         reg, err);
 269         return err;
 270 }
 271
 272 static inline bool offset_is_oscio(struct sx150x_chip *chip, unsigned offset)
 273 {
 274         return (chip->dev_cfg->ngpios == offset);
 275 }
 276
 277 /*
 278  * These utility functions solve the common problem of locating and setting
 279  * configuration bits.  Configuration bits are grouped into registers
 280  * whose indexes increase downwards.  For example, with eight-bit registers,
 281  * sixteen gpios would have their config bits grouped in the following order:
 282  * REGISTER N-1 [ f e d c b a 9 8 ]
 283  *          N   [ 7 6 5 4 3 2 1 0 ]
 284  *
 285  * For multi-bit configurations, the pattern gets wider:
 286  * REGISTER N-3 [ f f e e d d c c ]
 287  *          N-2 [ b b a a 9 9 8 8 ]
 288  *          N-1 [ 7 7 6 6 5 5 4 4 ]
 289  *          N   [ 3 3 2 2 1 1 0 0 ]
 290  *
 291  * Given the address of the starting register 'N', the index of the gpio
 292  * whose configuration we seek to change, and the width in bits of that
 293  * configuration, these functions allow us to locate the correct
 294  * register and mask the correct bits.
 295  */
 296 static inline void sx150x_find_cfg(u8 offset, u8 width,
 297                                 u8 *reg, u8 *mask, u8 *shift)
 298 {
 299         *reg   -= offset * width / 8;
 300         *mask   = (1 << width) - 1;
 301         *shift  = (offset * width) % 8;
 302         *mask <<= *shift;
 303 }
 304
 305 static s32 sx150x_write_cfg(struct sx150x_chip *chip,
 306                         u8 offset, u8 width, u8 reg, u8 val)
 307 {
 308         u8  mask;
 309         u8  data;
 310         u8  shift;
 311         s32 err;
 312
 313         sx150x_find_cfg(offset, width, &reg, &mask, &shift);
 314         err = sx150x_i2c_read(chip->client, reg, &data);
 315         if (err < 0)
 316                 return err;
 317
 318         data &= ~mask;
 319         data |= (val << shift) & mask;
 320         return sx150x_i2c_write(chip->client, reg, data);
 321 }
 322
 323 static int sx150x_get_io(struct sx150x_chip *chip, unsigned offset)
 324 {
 325         u8  reg = chip->dev_cfg->reg_data;
 326         u8  mask;
 327         u8  data;
 328         u8  shift;
 329         s32 err;
 330
 331         sx150x_find_cfg(offset, 1, &reg, &mask, &shift);
 332         err = sx150x_i2c_read(chip->client, reg, &data);
 333         if (err >= 0)
 334                 err = (data & mask) != 0 ? 1 : 0;
 335
 336         return err;
 337 }
 338
 339 static void sx150x_set_oscio(struct sx150x_chip *chip, int val)
 340 {
 341         sx150x_i2c_write(chip->client,
 342                         chip->dev_cfg->pri.x789.reg_clock,
 343                         (val ? 0x1f : 0x10));
 344 }
 345
 346 static void sx150x_set_io(struct sx150x_chip *chip, unsigned offset, int val)
 347 {
 348         sx150x_write_cfg(chip,
 349                         offset,
 350                         1,
 351                         chip->dev_cfg->reg_data,
 352                         (val ? 1 : 0));
 353 }
 354
 355 static int sx150x_io_input(struct sx150x_chip *chip, unsigned offset)
 356 {
 357         return sx150x_write_cfg(chip,
 358                                 offset,
 359                                 1,
 360                                 chip->dev_cfg->reg_dir,
 361                                 1);
 362 }
 363
 364 static int sx150x_io_output(struct sx150x_chip *chip, unsigned offset, int val)
 365 {
 366         int err;
 367
 368         err = sx150x_write_cfg(chip,
 369                         offset,
 370                         1,
 371                         chip->dev_cfg->reg_data,
 372                         (val ? 1 : 0));
 373         if (err >= 0)
 374                 err = sx150x_write_cfg(chip,
 375                                 offset,
 376                                 1,
 377                                 chip->dev_cfg->reg_dir,
 378                                 0);
 379         return err;
 380 }
 381
 382 static int sx150x_gpio_get(struct gpio_chip *gc, unsigned offset)
 383 {
 384         struct sx150x_chip *chip = gpiochip_get_data(gc);
 385         int status = -EINVAL;
 386
 387         if (!offset_is_oscio(chip, offset)) {
 388                 mutex_lock(&chip->lock);
 389                 status = sx150x_get_io(chip, offset);
 390                 mutex_unlock(&chip->lock);
 391         }
 392
 393         return (status < 0) ? status : !!status;
 394 }
 395
 396 static void sx150x_gpio_set(struct gpio_chip *gc, unsigned offset, int val)
 397 {
 398         struct sx150x_chip *chip = gpiochip_get_data(gc);
 399
 400         mutex_lock(&chip->lock);
 401         if (offset_is_oscio(chip, offset))
 402                 sx150x_set_oscio(chip, val);
 403         else
 404                 sx150x_set_io(chip, offset, val);
 405         mutex_unlock(&chip->lock);
 406 }
 407
 408 static int sx150x_gpio_set_single_ended(struct gpio_chip *gc,
 409                                         unsigned offset,
 410                                         enum single_ended_mode mode)
 411 {
 412         struct sx150x_chip *chip = gpiochip_get_data(gc);
 413
 414         /* On the SX160X 789 we can set open drain */
 415         if (chip->dev_cfg->model != SX150X_789)
 416                 return -ENOTSUPP;
 417
 418         if (mode == LINE_MODE_PUSH_PULL)
 419                 return sx150x_write_cfg(chip,
 420                                         offset,
 421                                         1,
 422                                         chip->dev_cfg->pri.x789.reg_drain,
 423                                         0);
 424
 425         if (mode == LINE_MODE_OPEN_DRAIN)
 426                 return sx150x_write_cfg(chip,
 427                                         offset,
 428                                         1,
 429                                         chip->dev_cfg->pri.x789.reg_drain,
 430                                         1);
 431         return -ENOTSUPP;
 432 }
 433
 434 static int sx150x_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
 435 {
 436         struct sx150x_chip *chip = gpiochip_get_data(gc);
 437         int status = -EINVAL;
 438
 439         if (!offset_is_oscio(chip, offset)) {
 440                 mutex_lock(&chip->lock);
 441                 status = sx150x_io_input(chip, offset);
 442                 mutex_unlock(&chip->lock);
 443         }
 444         return status;
 445 }
 446
 447 static int sx150x_gpio_direction_output(struct gpio_chip *gc,
 448                                         unsigned offset,
 449                                         int val)
 450 {
 451         struct sx150x_chip *chip = gpiochip_get_data(gc);
 452         int status = 0;
 453
 454         if (!offset_is_oscio(chip, offset)) {
 455                 mutex_lock(&chip->lock);
 456                 status = sx150x_io_output(chip, offset, val);
 457                 mutex_unlock(&chip->lock);
 458         }
 459         return status;
 460 }
 461
 462 static void sx150x_irq_mask(struct irq_data *d)
 463 {
 464         struct sx150x_chip *chip = gpiochip_get_data(irq_data_get_irq_chip_data(d));
 465         unsigned n = d->hwirq;
 466
 467         chip->irq_masked |= (1 << n);
 468         chip->irq_update = n;
 469 }
 470
 471 static void sx150x_irq_unmask(struct irq_data *d)
 472 {
 473         struct sx150x_chip *chip = gpiochip_get_data(irq_data_get_irq_chip_data(d));
 474         unsigned n = d->hwirq;
 475
 476         chip->irq_masked &= ~(1 << n);
 477         chip->irq_update = n;
 478 }
 479
 480 static int sx150x_irq_set_type(struct irq_data *d, unsigned int flow_type)
 481 {
 482         struct sx150x_chip *chip = gpiochip_get_data(irq_data_get_irq_chip_data(d));
 483         unsigned n, val = 0;
 484
 485         if (flow_type & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
 486                 return -EINVAL;
 487
 488         n = d->hwirq;
 489
 490         if (flow_type & IRQ_TYPE_EDGE_RISING)
 491                 val |= 0x1;
 492         if (flow_type & IRQ_TYPE_EDGE_FALLING)
 493                 val |= 0x2;
 494
 495         chip->irq_sense &= ~(3UL << (n * 2));
 496         chip->irq_sense |= val << (n * 2);
 497         chip->irq_update = n;
 498         return 0;
 499 }
 500
 501 static irqreturn_t sx150x_irq_thread_fn(int irq, void *dev_id)
 502 {
 503         struct sx150x_chip *chip = (struct sx150x_chip *)dev_id;
 504         unsigned nhandled = 0;
 505         unsigned sub_irq;
 506         unsigned n;
 507         s32 err;
 508         u8 val;
 509         int i;
 510
 511         for (i = (chip->dev_cfg->ngpios / 8) - 1; i >= 0; --i) {
 512                 err = sx150x_i2c_read(chip->client,
 513                                       chip->dev_cfg->reg_irq_src - i,
 514                                       &val);
 515                 if (err < 0)
 516                         continue;
 517
 518                 sx150x_i2c_write(chip->client,
 519                                 chip->dev_cfg->reg_irq_src - i,
 520                                 val);
 521                 for (n = 0; n < 8; ++n) {
 522                         if (val & (1 << n)) {
 523                                 sub_irq = irq_find_mapping(
 524                                         chip->gpio_chip.irqdomain,
 525                                         (i * 8) + n);
 526                                 handle_nested_irq(sub_irq);
 527                                 ++nhandled;
 528                         }
 529                 }
 530         }
 531
 532         return (nhandled > 0 ? IRQ_HANDLED : IRQ_NONE);
 533 }
 534
 535 static void sx150x_irq_bus_lock(struct irq_data *d)
 536 {
 537         struct sx150x_chip *chip = gpiochip_get_data(irq_data_get_irq_chip_data(d));
 538
 539         mutex_lock(&chip->lock);
 540 }
 541
 542 static void sx150x_irq_bus_sync_unlock(struct irq_data *d)
 543 {
 544         struct sx150x_chip *chip = gpiochip_get_data(irq_data_get_irq_chip_data(d));
 545         unsigned n;
 546
 547         if (chip->irq_update == NO_UPDATE_PENDING)
 548                 goto out;
 549
 550         n = chip->irq_update;
 551         chip->irq_update = NO_UPDATE_PENDING;
 552
 553         /* Avoid updates if nothing changed */
 554         if (chip->dev_sense == chip->irq_sense &&
 555             chip->dev_masked == chip->irq_masked)
 556                 goto out;
 557
 558         chip->dev_sense = chip->irq_sense;
 559         chip->dev_masked = chip->irq_masked;
 560
 561         if (chip->irq_masked & (1 << n)) {
 562                 sx150x_write_cfg(chip, n, 1, chip->dev_cfg->reg_irq_mask, 1);
 563                 sx150x_write_cfg(chip, n, 2, chip->dev_cfg->reg_sense, 0);
 564         } else {
 565                 sx150x_write_cfg(chip, n, 1, chip->dev_cfg->reg_irq_mask, 0);
 566                 sx150x_write_cfg(chip, n, 2, chip->dev_cfg->reg_sense,
 567                                  chip->irq_sense >> (n * 2));
 568         }
 569 out:
 570         mutex_unlock(&chip->lock);
 571 }
 572
 573 static void sx150x_init_chip(struct sx150x_chip *chip,
 574                         struct i2c_client *client,
 575                         kernel_ulong_t driver_data,
 576                         struct sx150x_platform_data *pdata)
 577 {
 578         mutex_init(&chip->lock);
 579
 580         chip->client                     = client;
 581         chip->dev_cfg                    = &sx150x_devices[driver_data];
 582         chip->gpio_chip.parent              = &client->dev;
 583         chip->gpio_chip.label            = client->name;
 584         chip->gpio_chip.direction_input  = sx150x_gpio_direction_input;
 585         chip->gpio_chip.direction_output = sx150x_gpio_direction_output;
 586         chip->gpio_chip.get              = sx150x_gpio_get;
 587         chip->gpio_chip.set              = sx150x_gpio_set;
 588         chip->gpio_chip.set_single_ended = sx150x_gpio_set_single_ended;
 589         chip->gpio_chip.base             = pdata->gpio_base;
 590         chip->gpio_chip.can_sleep        = true;
 591         chip->gpio_chip.ngpio            = chip->dev_cfg->ngpios;
 592 #ifdef CONFIG_OF_GPIO
 593         chip->gpio_chip.of_node          = client->dev.of_node;
 594         chip->gpio_chip.of_gpio_n_cells  = 2;
 595 #endif
 596         if (pdata->oscio_is_gpo)
 597                 ++chip->gpio_chip.ngpio;
 598
 599         chip->irq_chip.name                = client->name;
 600         chip->irq_chip.irq_mask            = sx150x_irq_mask;
 601         chip->irq_chip.irq_unmask          = sx150x_irq_unmask;
 602         chip->irq_chip.irq_set_type        = sx150x_irq_set_type;
 603         chip->irq_chip.irq_bus_lock        = sx150x_irq_bus_lock;
 604         chip->irq_chip.irq_bus_sync_unlock = sx150x_irq_bus_sync_unlock;
 605         chip->irq_summary                  = -1;
 606         chip->irq_base                     = -1;
 607         chip->irq_masked                   = ~0;
 608         chip->irq_sense                    = 0;
 609         chip->dev_masked                   = ~0;
 610         chip->dev_sense                    = 0;
 611         chip->irq_update                   = NO_UPDATE_PENDING;
 612 }
 613
 614 static int sx150x_init_io(struct sx150x_chip *chip, u8 base, u16 cfg)
 615 {
 616         int err = 0;
 617         unsigned n;
 618
 619         for (n = 0; err >= 0 && n < (chip->dev_cfg->ngpios / 8); ++n)
 620                 err = sx150x_i2c_write(chip->client, base - n, cfg >> (n * 8));
 621         return err;
 622 }
 623
 624 static int sx150x_reset(struct sx150x_chip *chip)
 625 {
 626         int err;
 627
 628         err = i2c_smbus_write_byte_data(chip->client,
 629                                         chip->dev_cfg->pri.x789.reg_reset,
 630                                         0x12);
 631         if (err < 0)
 632                 return err;
 633
 634         err = i2c_smbus_write_byte_data(chip->client,
 635                                         chip->dev_cfg->pri.x789.reg_reset,
 636                                         0x34);
 637         return err;
 638 }
 639
 640 static int sx150x_init_hw(struct sx150x_chip *chip,
 641                         struct sx150x_platform_data *pdata)
 642 {
 643         int err = 0;
 644
 645         if (pdata->reset_during_probe) {
 646                 err = sx150x_reset(chip);
 647                 if (err < 0)
 648                         return err;
 649         }
 650
 651         if (chip->dev_cfg->model == SX150X_789)
 652                 err = sx150x_i2c_write(chip->client,
 653                                 chip->dev_cfg->pri.x789.reg_misc,
 654                                 0x01);
 655         else if (chip->dev_cfg->model == SX150X_456)
 656                 err = sx150x_i2c_write(chip->client,
 657                                 chip->dev_cfg->pri.x456.reg_advance,
 658                                 0x04);
 659         else
 660                 err = sx150x_i2c_write(chip->client,
 661                                 chip->dev_cfg->pri.x123.reg_advance,
 662                                 0x00);
 663         if (err < 0)
 664                 return err;
 665
 666         err = sx150x_init_io(chip, chip->dev_cfg->reg_pullup,
 667                         pdata->io_pullup_ena);
 668         if (err < 0)
 669                 return err;
 670
 671         err = sx150x_init_io(chip, chip->dev_cfg->reg_pulldn,
 672                         pdata->io_pulldn_ena);
 673         if (err < 0)
 674                 return err;
 675
 676         if (chip->dev_cfg->model == SX150X_789) {
 677                 err = sx150x_init_io(chip,
 678                                 chip->dev_cfg->pri.x789.reg_polarity,
 679                                 pdata->io_polarity);
 680                 if (err < 0)
 681                         return err;
 682         } else if (chip->dev_cfg->model == SX150X_456) {
 683                 /* Set all pins to work in normal mode */
 684                 err = sx150x_init_io(chip,
 685                                 chip->dev_cfg->pri.x456.reg_pld_mode,
 686                                 0);
 687                 if (err < 0)
 688                         return err;
 689         } else {
 690                 /* Set all pins to work in normal mode */
 691                 err = sx150x_init_io(chip,
 692                                 chip->dev_cfg->pri.x123.reg_pld_mode,
 693                                 0);
 694                 if (err < 0)
 695                         return err;
 696         }
 697
 698
 699         if (pdata->oscio_is_gpo)
 700                 sx150x_set_oscio(chip, 0);
 701
 702         return err;
 703 }
 704
 705 static int sx150x_install_irq_chip(struct sx150x_chip *chip,
 706                                 int irq_summary,
 707                                 int irq_base)
 708 {
 709         int err;
 710
 711         chip->irq_summary = irq_summary;
 712         chip->irq_base    = irq_base;
 713
 714         /* Add gpio chip to irq subsystem */
 715         err = gpiochip_irqchip_add(&chip->gpio_chip,
 716                 &chip->irq_chip, chip->irq_base,
 717                 handle_edge_irq, IRQ_TYPE_EDGE_BOTH);
 718         if (err) {
 719                 dev_err(&chip->client->dev,
 720                         "could not connect irqchip to gpiochip\n");
 721                 return  err;
 722         }
 723
 724         err = devm_request_threaded_irq(&chip->client->dev,
 725                         irq_summary, NULL, sx150x_irq_thread_fn,
 726                         IRQF_ONESHOT | IRQF_SHARED | IRQF_TRIGGER_FALLING,
 727                         chip->irq_chip.name, chip);
 728         if (err < 0) {
 729                 chip->irq_summary = -1;
 730                 chip->irq_base    = -1;
 731         }
 732
 733         return err;
 734 }
 735
 736 static int sx150x_probe(struct i2c_client *client,
 737                                 const struct i2c_device_id *id)
 738 {
 739         static const u32 i2c_funcs = I2C_FUNC_SMBUS_BYTE_DATA |
 740                                      I2C_FUNC_SMBUS_WRITE_WORD_DATA;
 741         struct sx150x_platform_data *pdata;
 742         struct sx150x_chip *chip;
 743         int rc;
 744
 745         pdata = dev_get_platdata(&client->dev);
 746         if (!pdata)
 747                 return -EINVAL;
 748
 749         if (!i2c_check_functionality(client->adapter, i2c_funcs))
 750                 return -ENOSYS;
 751
 752         chip = devm_kzalloc(&client->dev,
 753                 sizeof(struct sx150x_chip), GFP_KERNEL);
 754         if (!chip)
 755                 return -ENOMEM;
 756
 757         sx150x_init_chip(chip, client, id->driver_data, pdata);
 758         rc = sx150x_init_hw(chip, pdata);
 759         if (rc < 0)
 760                 return rc;
 761
 762         rc = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip);
 763         if (rc)
 764                 return rc;
 765
 766         if (pdata->irq_summary >= 0) {
 767                 rc = sx150x_install_irq_chip(chip,
 768                                         pdata->irq_summary,
 769                                         pdata->irq_base);
 770                 if (rc < 0)
 771                         return rc;
 772         }
 773
 774         i2c_set_clientdata(client, chip);
 775
 776         return 0;
 777 }
 778
 779 static struct i2c_driver sx150x_driver = {
 780         .driver = {
 781                 .name = "sx150x",
 782                 .of_match_table = of_match_ptr(sx150x_of_match),
 783         },
 784         .probe    = sx150x_probe,
 785         .id_table = sx150x_id,
 786 };
 787
 788 static int __init sx150x_init(void)
 789 {
 790         return i2c_add_driver(&sx150x_driver);
 791 }
 792 subsys_initcall(sx150x_init);