drivers/mfd/htc-i2cpld.c

   1 /*
   2  *  htc-i2cpld.c
   3  *  Chip driver for an unknown CPLD chip found on omap850 HTC devices like
   4  *  the HTC Wizard and HTC Herald.
   5  *  The cpld is located on the i2c bus and acts as an input/output GPIO
   6  *  extender.
   7  *
   8  *  Copyright (C) 2009 Cory Maccarrone <darkstar6262@gmail.com>
   9  *
  10  *  Based on work done in the linwizard project
  11  *  Copyright (C) 2008-2009 Angelo Arrifano <miknix@gmail.com>
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2 of the License, or
  16  * (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  26  */
  27
  28 #include <linux/kernel.h>
  29 #include <linux/init.h>
  30 #include <linux/module.h>
  31 #include <linux/interrupt.h>
  32 #include <linux/platform_device.h>
  33 #include <linux/i2c.h>
  34 #include <linux/irq.h>
  35 #include <linux/spinlock.h>
  36 #include <linux/htcpld.h>
  37 #include <linux/gpio.h>
  38
  39 struct htcpld_chip {
  40         spinlock_t              lock;
  41
  42         /* chip info */
  43         u8                      reset;
  44         u8                      addr;
  45         struct device           *dev;
  46         struct i2c_client       *client;
  47
  48         /* Output details */
  49         u8                      cache_out;
  50         struct gpio_chip        chip_out;
  51
  52         /* Input details */
  53         u8                      cache_in;
  54         struct gpio_chip        chip_in;
  55
  56         u16                     irqs_enabled;
  57         uint                    irq_start;
  58         int                     nirqs;
  59
  60         /*
  61          * Work structure to allow for setting values outside of any
  62          * possible interrupt context
  63          */
  64         struct work_struct set_val_work;
  65 };
  66
  67 struct htcpld_data {
  68         /* irq info */
  69         u16                irqs_enabled;
  70         uint               irq_start;
  71         int                nirqs;
  72         uint               chained_irq;
  73         unsigned int       int_reset_gpio_hi;
  74         unsigned int       int_reset_gpio_lo;
  75
  76         /* htcpld info */
  77         struct htcpld_chip *chip;
  78         unsigned int       nchips;
  79 };
  80
  81 /* There does not appear to be a way to proactively mask interrupts
  82  * on the htcpld chip itself.  So, we simply ignore interrupts that
  83  * aren't desired. */
  84 static void htcpld_mask(unsigned int irq)
  85 {
  86         struct htcpld_chip *chip = get_irq_chip_data(irq);
  87         chip->irqs_enabled &= ~(1 << (irq - chip->irq_start));
  88         pr_debug("HTCPLD mask %d %04x\n", irq, chip->irqs_enabled);
  89 }
  90 static void htcpld_unmask(unsigned int irq)
  91 {
  92         struct htcpld_chip *chip = get_irq_chip_data(irq);
  93         chip->irqs_enabled |= 1 << (irq - chip->irq_start);
  94         pr_debug("HTCPLD unmask %d %04x\n", irq, chip->irqs_enabled);
  95 }
  96
  97 static int htcpld_set_type(unsigned int irq, unsigned int flags)
  98 {
  99         struct irq_desc *d = irq_to_desc(irq);
 100
 101         if (!d) {
 102                 pr_err("HTCPLD invalid IRQ: %d\n", irq);
 103                 return -EINVAL;
 104         }
 105
 106         if (flags & ~IRQ_TYPE_SENSE_MASK)
 107                 return -EINVAL;
 108
 109         /* We only allow edge triggering */
 110         if (flags & (IRQ_TYPE_LEVEL_LOW|IRQ_TYPE_LEVEL_HIGH))
 111                 return -EINVAL;
 112
 113         d->status &= ~IRQ_TYPE_SENSE_MASK;
 114         d->status |= flags;
 115
 116         return 0;
 117 }
 118
 119 static struct irq_chip htcpld_muxed_chip = {
 120         .name     = "htcpld",
 121         .mask     = htcpld_mask,
 122         .unmask   = htcpld_unmask,
 123         .set_type = htcpld_set_type,
 124 };
 125
 126 /* To properly dispatch IRQ events, we need to read from the
 127  * chip.  This is an I2C action that could possibly sleep
 128  * (which is bad in interrupt context) -- so we use a threaded
 129  * interrupt handler to get around that.
 130  */
 131 static irqreturn_t htcpld_handler(int irq, void *dev)
 132 {
 133         struct htcpld_data *htcpld = dev;
 134         unsigned int i;
 135         unsigned long flags;
 136         int irqpin;
 137         struct irq_desc *desc;
 138
 139         if (!htcpld) {
 140                 pr_debug("htcpld is null in ISR\n");
 141                 return IRQ_HANDLED;
 142         }
 143
 144         /*
 145          * For each chip, do a read of the chip and trigger any interrupts
 146          * desired.  The interrupts will be triggered from LSB to MSB (i.e.
 147          * bit 0 first, then bit 1, etc.)
 148          *
 149          * For chips that have no interrupt range specified, just skip 'em.
 150          */
 151         for (i = 0; i < htcpld->nchips; i++) {
 152                 struct htcpld_chip *chip = &htcpld->chip[i];
 153                 struct i2c_client *client;
 154                 int val;
 155                 unsigned long uval, old_val;
 156
 157                 if (!chip) {
 158                         pr_debug("chip %d is null in ISR\n", i);
 159                         continue;
 160                 }
 161
 162                 if (chip->nirqs == 0)
 163                         continue;
 164
 165                 client = chip->client;
 166                 if (!client) {
 167                         pr_debug("client %d is null in ISR\n", i);
 168                         continue;
 169                 }
 170
 171                 /* Scan the chip */
 172                 val = i2c_smbus_read_byte_data(client, chip->cache_out);
 173                 if (val < 0) {
 174                         /* Throw a warning and skip this chip */
 175                         dev_warn(chip->dev, "Unable to read from chip: %d\n",
 176                                  val);
 177                         continue;
 178                 }
 179
 180                 uval = (unsigned long)val;
 181
 182                 spin_lock_irqsave(&chip->lock, flags);
 183
 184                 /* Save away the old value so we can compare it */
 185                 old_val = chip->cache_in;
 186
 187                 /* Write the new value */
 188                 chip->cache_in = uval;
 189
 190                 spin_unlock_irqrestore(&chip->lock, flags);
 191
 192                 /*
 193                  * For each bit in the data (starting at bit 0), trigger
 194                  * associated interrupts.
 195                  */
 196                 for (irqpin = 0; irqpin < chip->nirqs; irqpin++) {
 197                         unsigned oldb, newb;
 198                         int flags;
 199
 200                         irq = chip->irq_start + irqpin;
 201                         desc = irq_to_desc(irq);
 202                         flags = desc->status;
 203
 204                         /* Run the IRQ handler, but only if the bit value
 205                          * changed, and the proper flags are set */
 206                         oldb = (old_val >> irqpin) & 1;
 207                         newb = (uval >> irqpin) & 1;
 208
 209                         if ((!oldb && newb && (flags & IRQ_TYPE_EDGE_RISING)) ||
 210                             (oldb && !newb &&
 211                              (flags & IRQ_TYPE_EDGE_FALLING))) {
 212                                 pr_debug("fire IRQ %d\n", irqpin);
 213                                 desc->handle_irq(irq, desc);
 214                         }
 215                 }
 216         }
 217
 218         /*
 219          * In order to continue receiving interrupts, the int_reset_gpio must
 220          * be asserted.
 221          */
 222         if (htcpld->int_reset_gpio_hi)
 223                 gpio_set_value(htcpld->int_reset_gpio_hi, 1);
 224         if (htcpld->int_reset_gpio_lo)
 225                 gpio_set_value(htcpld->int_reset_gpio_lo, 0);
 226
 227         return IRQ_HANDLED;
 228 }
 229
 230 /*
 231  * The GPIO set routines can be called from interrupt context, especially if,
 232  * for example they're attached to the led-gpio framework and a trigger is
 233  * enabled.  As such, we declared work above in the htcpld_chip structure,
 234  * and that work is scheduled in the set routine.  The kernel can then run
 235  * the I2C functions, which will sleep, in process context.
 236  */
 237 void htcpld_chip_set(struct gpio_chip *chip, unsigned offset, int val)
 238 {
 239         struct i2c_client *client;
 240         struct htcpld_chip *chip_data;
 241         unsigned long flags;
 242
 243         chip_data = container_of(chip, struct htcpld_chip, chip_out);
 244         if (!chip_data)
 245                 return;
 246
 247         client = chip_data->client;
 248         if (client == NULL)
 249                 return;
 250
 251         spin_lock_irqsave(&chip_data->lock, flags);
 252         if (val)
 253                 chip_data->cache_out |= (1 << offset);
 254         else
 255                 chip_data->cache_out &= ~(1 << offset);
 256         spin_unlock_irqrestore(&chip_data->lock, flags);
 257
 258         schedule_work(&(chip_data->set_val_work));
 259 }
 260
 261 void htcpld_chip_set_ni(struct work_struct *work)
 262 {
 263         struct htcpld_chip *chip_data;
 264         struct i2c_client *client;
 265
 266         chip_data = container_of(work, struct htcpld_chip, set_val_work);
 267         client = chip_data->client;
 268         i2c_smbus_read_byte_data(client, chip_data->cache_out);
 269 }
 270
 271 int htcpld_chip_get(struct gpio_chip *chip, unsigned offset)
 272 {
 273         struct htcpld_chip *chip_data;
 274         int val = 0;
 275         int is_input = 0;
 276
 277         /* Try out first */
 278         chip_data = container_of(chip, struct htcpld_chip, chip_out);
 279         if (!chip_data) {
 280                 /* Try in */
 281                 is_input = 1;
 282                 chip_data = container_of(chip, struct htcpld_chip, chip_in);
 283                 if (!chip_data)
 284                         return -EINVAL;
 285         }
 286
 287         /* Determine if this is an input or output GPIO */
 288         if (!is_input)
 289                 /* Use the output cache */
 290                 val = (chip_data->cache_out >> offset) & 1;
 291         else
 292                 /* Use the input cache */
 293                 val = (chip_data->cache_in >> offset) & 1;
 294
 295         if (val)
 296                 return 1;
 297         else
 298                 return 0;
 299 }
 300
 301 static int htcpld_direction_output(struct gpio_chip *chip,
 302                                         unsigned offset, int value)
 303 {
 304         htcpld_chip_set(chip, offset, value);
 305         return 0;
 306 }
 307
 308 static int htcpld_direction_input(struct gpio_chip *chip,
 309                                         unsigned offset)
 310 {
 311         /*
 312          * No-op: this function can only be called on the input chip.
 313          * We do however make sure the offset is within range.
 314          */
 315         return (offset < chip->ngpio) ? 0 : -EINVAL;
 316 }
 317
 318 int htcpld_chip_to_irq(struct gpio_chip *chip, unsigned offset)
 319 {
 320         struct htcpld_chip *chip_data;
 321
 322         chip_data = container_of(chip, struct htcpld_chip, chip_in);
 323
 324         if (offset < chip_data->nirqs)
 325                 return chip_data->irq_start + offset;
 326         else
 327                 return -EINVAL;
 328 }
 329
 330 void htcpld_chip_reset(struct i2c_client *client)
 331 {
 332         struct htcpld_chip *chip_data = i2c_get_clientdata(client);
 333         if (!chip_data)
 334                 return;
 335
 336         i2c_smbus_read_byte_data(
 337                 client, (chip_data->cache_out = chip_data->reset));
 338 }
 339
 340 static int __devinit htcpld_setup_chip_irq(
 341                 struct platform_device *pdev,
 342                 int chip_index)
 343 {
 344         struct htcpld_data *htcpld;
 345         struct device *dev = &pdev->dev;
 346         struct htcpld_core_platform_data *pdata;
 347         struct htcpld_chip *chip;
 348         struct htcpld_chip_platform_data *plat_chip_data;
 349         unsigned int irq, irq_end;
 350         int ret = 0;
 351
 352         /* Get the platform and driver data */
 353         pdata = dev->platform_data;
 354         htcpld = platform_get_drvdata(pdev);
 355         chip = &htcpld->chip[chip_index];
 356         plat_chip_data = &pdata->chip[chip_index];
 357
 358         /* Setup irq handlers */
 359         irq_end = chip->irq_start + chip->nirqs;
 360         for (irq = chip->irq_start; irq < irq_end; irq++) {
 361                 set_irq_chip(irq, &htcpld_muxed_chip);
 362                 set_irq_chip_data(irq, chip);
 363                 set_irq_handler(irq, handle_simple_irq);
 364 #ifdef CONFIG_ARM
 365                 set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
 366 #else
 367                 set_irq_probe(irq);
 368 #endif
 369         }
 370
 371         return ret;
 372 }
 373
 374 static int __devinit htcpld_register_chip_i2c(
 375                 struct platform_device *pdev,
 376                 int chip_index)
 377 {
 378         struct htcpld_data *htcpld;
 379         struct device *dev = &pdev->dev;
 380         struct htcpld_core_platform_data *pdata;
 381         struct htcpld_chip *chip;
 382         struct htcpld_chip_platform_data *plat_chip_data;
 383         struct i2c_adapter *adapter;
 384         struct i2c_client *client;
 385         struct i2c_board_info info;
 386
 387         /* Get the platform and driver data */
 388         pdata = dev->platform_data;
 389         htcpld = platform_get_drvdata(pdev);
 390         chip = &htcpld->chip[chip_index];
 391         plat_chip_data = &pdata->chip[chip_index];
 392
 393         adapter = i2c_get_adapter(pdata->i2c_adapter_id);
 394         if (adapter == NULL) {
 395                 /* Eek, no such I2C adapter!  Bail out. */
 396                 dev_warn(dev, "Chip at i2c address 0x%x: Invalid i2c adapter %d\n",
 397                          plat_chip_data->addr, pdata->i2c_adapter_id);
 398                 return -ENODEV;
 399         }
 400
 401         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA)) {
 402                 dev_warn(dev, "i2c adapter %d non-functional\n",
 403                          pdata->i2c_adapter_id);
 404                 return -EINVAL;
 405         }
 406
 407         memset(&info, 0, sizeof(struct i2c_board_info));
 408         info.addr = plat_chip_data->addr;
 409         strlcpy(info.type, "htcpld-chip", I2C_NAME_SIZE);
 410         info.platform_data = chip;
 411
 412         /* Add the I2C device.  This calls the probe() function. */
 413         client = i2c_new_device(adapter, &info);
 414         if (!client) {
 415                 /* I2C device registration failed, contineu with the next */
 416                 dev_warn(dev, "Unable to add I2C device for 0x%x\n",
 417                          plat_chip_data->addr);
 418                 return -ENODEV;
 419         }
 420
 421         i2c_set_clientdata(client, chip);
 422         snprintf(client->name, I2C_NAME_SIZE, "Chip_0x%d", client->addr);
 423         chip->client = client;
 424
 425         /* Reset the chip */
 426         htcpld_chip_reset(client);
 427         chip->cache_in = i2c_smbus_read_byte_data(client, chip->cache_out);
 428
 429         return 0;
 430 }
 431
 432 static void __devinit htcpld_unregister_chip_i2c(
 433                 struct platform_device *pdev,
 434                 int chip_index)
 435 {
 436         struct htcpld_data *htcpld;
 437         struct htcpld_chip *chip;
 438
 439         /* Get the platform and driver data */
 440         htcpld = platform_get_drvdata(pdev);
 441         chip = &htcpld->chip[chip_index];
 442
 443         if (chip->client)
 444                 i2c_unregister_device(chip->client);
 445 }
 446
 447 static int __devinit htcpld_register_chip_gpio(
 448                 struct platform_device *pdev,
 449                 int chip_index)
 450 {
 451         struct htcpld_data *htcpld;
 452         struct device *dev = &pdev->dev;
 453         struct htcpld_core_platform_data *pdata;
 454         struct htcpld_chip *chip;
 455         struct htcpld_chip_platform_data *plat_chip_data;
 456         struct gpio_chip *gpio_chip;
 457         int ret = 0;
 458
 459         /* Get the platform and driver data */
 460         pdata = dev->platform_data;
 461         htcpld = platform_get_drvdata(pdev);
 462         chip = &htcpld->chip[chip_index];
 463         plat_chip_data = &pdata->chip[chip_index];
 464
 465         /* Setup the GPIO chips */
 466         gpio_chip = &(chip->chip_out);
 467         gpio_chip->label           = "htcpld-out";
 468         gpio_chip->dev             = dev;
 469         gpio_chip->owner           = THIS_MODULE;
 470         gpio_chip->get             = htcpld_chip_get;
 471         gpio_chip->set             = htcpld_chip_set;
 472         gpio_chip->direction_input = NULL;
 473         gpio_chip->direction_output = htcpld_direction_output;
 474         gpio_chip->base            = plat_chip_data->gpio_out_base;
 475         gpio_chip->ngpio           = plat_chip_data->num_gpios;
 476
 477         gpio_chip = &(chip->chip_in);
 478         gpio_chip->label           = "htcpld-in";
 479         gpio_chip->dev             = dev;
 480         gpio_chip->owner           = THIS_MODULE;
 481         gpio_chip->get             = htcpld_chip_get;
 482         gpio_chip->set             = NULL;
 483         gpio_chip->direction_input = htcpld_direction_input;
 484         gpio_chip->direction_output = NULL;
 485         gpio_chip->to_irq          = htcpld_chip_to_irq;
 486         gpio_chip->base            = plat_chip_data->gpio_in_base;
 487         gpio_chip->ngpio           = plat_chip_data->num_gpios;
 488
 489         /* Add the GPIO chips */
 490         ret = gpiochip_add(&(chip->chip_out));
 491         if (ret) {
 492                 dev_warn(dev, "Unable to register output GPIOs for 0x%x: %d\n",
 493                          plat_chip_data->addr, ret);
 494                 return ret;
 495         }
 496
 497         ret = gpiochip_add(&(chip->chip_in));
 498         if (ret) {
 499                 int error;
 500
 501                 dev_warn(dev, "Unable to register input GPIOs for 0x%x: %d\n",
 502                          plat_chip_data->addr, ret);
 503
 504                 error = gpiochip_remove(&(chip->chip_out));
 505                 if (error)
 506                         dev_warn(dev, "Error while trying to unregister gpio chip: %d\n", error);
 507
 508                 return ret;
 509         }
 510
 511         return 0;
 512 }
 513
 514 static int __devinit htcpld_setup_chips(struct platform_device *pdev)
 515 {
 516         struct htcpld_data *htcpld;
 517         struct device *dev = &pdev->dev;
 518         struct htcpld_core_platform_data *pdata;
 519         int i;
 520
 521         /* Get the platform and driver data */
 522         pdata = dev->platform_data;
 523         htcpld = platform_get_drvdata(pdev);
 524
 525         /* Setup each chip's output GPIOs */
 526         htcpld->nchips = pdata->num_chip;
 527         htcpld->chip = kzalloc(sizeof(struct htcpld_chip) * htcpld->nchips,
 528                                GFP_KERNEL);
 529         if (!htcpld->chip) {
 530                 dev_warn(dev, "Unable to allocate memory for chips\n");
 531                 return -ENOMEM;
 532         }
 533
 534         /* Add the chips as best we can */
 535         for (i = 0; i < htcpld->nchips; i++) {
 536                 int ret;
 537
 538                 /* Setup the HTCPLD chips */
 539                 htcpld->chip[i].reset = pdata->chip[i].reset;
 540                 htcpld->chip[i].cache_out = pdata->chip[i].reset;
 541                 htcpld->chip[i].cache_in = 0;
 542                 htcpld->chip[i].dev = dev;
 543                 htcpld->chip[i].irq_start = pdata->chip[i].irq_base;
 544                 htcpld->chip[i].nirqs = pdata->chip[i].num_irqs;
 545
 546                 INIT_WORK(&(htcpld->chip[i].set_val_work), &htcpld_chip_set_ni);
 547                 spin_lock_init(&(htcpld->chip[i].lock));
 548
 549                 /* Setup the interrupts for the chip */
 550                 if (htcpld->chained_irq) {
 551                         ret = htcpld_setup_chip_irq(pdev, i);
 552                         if (ret)
 553                                 continue;
 554                 }
 555
 556                 /* Register the chip with I2C */
 557                 ret = htcpld_register_chip_i2c(pdev, i);
 558                 if (ret)
 559                         continue;
 560
 561
 562                 /* Register the chips with the GPIO subsystem */
 563                 ret = htcpld_register_chip_gpio(pdev, i);
 564                 if (ret) {
 565                         /* Unregister the chip from i2c and continue */
 566                         htcpld_unregister_chip_i2c(pdev, i);
 567                         continue;
 568                 }
 569
 570                 dev_info(dev, "Registered chip at 0x%x\n", pdata->chip[i].addr);
 571         }
 572
 573         return 0;
 574 }
 575
 576 static int __devinit htcpld_core_probe(struct platform_device *pdev)
 577 {
 578         struct htcpld_data *htcpld;
 579         struct device *dev = &pdev->dev;
 580         struct htcpld_core_platform_data *pdata;
 581         struct resource *res;
 582         int ret = 0;
 583
 584         if (!dev)
 585                 return -ENODEV;
 586
 587         pdata = dev->platform_data;
 588         if (!pdata) {
 589                 dev_warn(dev, "Platform data not found for htcpld core!\n");
 590                 return -ENXIO;
 591         }
 592
 593         htcpld = kzalloc(sizeof(struct htcpld_data), GFP_KERNEL);
 594         if (!htcpld)
 595                 return -ENOMEM;
 596
 597         /* Find chained irq */
 598         ret = -EINVAL;
 599         res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 600         if (res) {
 601                 int flags;
 602                 htcpld->chained_irq = res->start;
 603
 604                 /* Setup the chained interrupt handler */
 605                 flags = IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING;
 606                 ret = request_threaded_irq(htcpld->chained_irq,
 607                                            NULL, htcpld_handler,
 608                                            flags, pdev->name, htcpld);
 609                 if (ret) {
 610                         dev_warn(dev, "Unable to setup chained irq handler: %d\n", ret);
 611                         goto fail;
 612                 } else
 613                         device_init_wakeup(dev, 0);
 614         }
 615
 616         /* Set the driver data */
 617         platform_set_drvdata(pdev, htcpld);
 618
 619         /* Setup the htcpld chips */
 620         ret = htcpld_setup_chips(pdev);
 621         if (ret)
 622                 goto fail;
 623
 624         /* Request the GPIO(s) for the int reset and set them up */
 625         if (pdata->int_reset_gpio_hi) {
 626                 ret = gpio_request(pdata->int_reset_gpio_hi, "htcpld-core");
 627                 if (ret) {
 628                         /*
 629                          * If it failed, that sucks, but we can probably
 630                          * continue on without it.
 631                          */
 632                         dev_warn(dev, "Unable to request int_reset_gpio_hi -- interrupts may not work\n");
 633                         htcpld->int_reset_gpio_hi = 0;
 634                 } else {
 635                         htcpld->int_reset_gpio_hi = pdata->int_reset_gpio_hi;
 636                         gpio_set_value(htcpld->int_reset_gpio_hi, 1);
 637                 }
 638         }
 639
 640         if (pdata->int_reset_gpio_lo) {
 641                 ret = gpio_request(pdata->int_reset_gpio_lo, "htcpld-core");
 642                 if (ret) {
 643                         /*
 644                          * If it failed, that sucks, but we can probably
 645                          * continue on without it.
 646                          */
 647                         dev_warn(dev, "Unable to request int_reset_gpio_lo -- interrupts may not work\n");
 648                         htcpld->int_reset_gpio_lo = 0;
 649                 } else {
 650                         htcpld->int_reset_gpio_lo = pdata->int_reset_gpio_lo;
 651                         gpio_set_value(htcpld->int_reset_gpio_lo, 0);
 652                 }
 653         }
 654
 655         dev_info(dev, "Initialized successfully\n");
 656         return 0;
 657
 658 fail:
 659         kfree(htcpld);
 660         return ret;
 661 }
 662
 663 /* The I2C Driver -- used internally */
 664 static const struct i2c_device_id htcpld_chip_id[] = {
 665         { "htcpld-chip", 0 },
 666         { }
 667 };
 668 MODULE_DEVICE_TABLE(i2c, htcpld_chip_id);
 669
 670
 671 static struct i2c_driver htcpld_chip_driver = {
 672         .driver = {
 673                 .name   = "htcpld-chip",
 674         },
 675         .id_table = htcpld_chip_id,
 676 };
 677
 678 /* The Core Driver */
 679 static struct platform_driver htcpld_core_driver = {
 680         .driver = {
 681                 .name = "i2c-htcpld",
 682         },
 683 };
 684
 685 static int __init htcpld_core_init(void)
 686 {
 687         int ret;
 688
 689         /* Register the I2C Chip driver */
 690         ret = i2c_add_driver(&htcpld_chip_driver);
 691         if (ret)
 692                 return ret;
 693
 694         /* Probe for our chips */
 695         return platform_driver_probe(&htcpld_core_driver, htcpld_core_probe);
 696 }
 697
 698 static void __exit htcpld_core_exit(void)
 699 {
 700         i2c_del_driver(&htcpld_chip_driver);
 701         platform_driver_unregister(&htcpld_core_driver);
 702 }
 703
 704 module_init(htcpld_core_init);
 705 module_exit(htcpld_core_exit);
 706
 707 MODULE_AUTHOR("Cory Maccarrone <darkstar6262@gmail.com>");
 708 MODULE_DESCRIPTION("I2C HTC PLD Driver");
 709 MODULE_LICENSE("GPL");
 710