drivers/gpio/gpio-bcm-kona.c

   1 /*
   2  * Copyright (C) 2012-2014 Broadcom Corporation
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation version 2.
   7  *
   8  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
   9  * kind, whether express or implied; without even the implied warranty
  10  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <linux/bitops.h>
  15 #include <linux/err.h>
  16 #include <linux/io.h>
  17 #include <linux/gpio.h>
  18 #include <linux/of_device.h>
  19 #include <linux/of_irq.h>
  20 #include <linux/module.h>
  21 #include <linux/irqdomain.h>
  22 #include <linux/irqchip/chained_irq.h>
  23
  24 #define BCM_GPIO_PASSWD                         0x00a5a501
  25 #define GPIO_PER_BANK                           32
  26 #define GPIO_MAX_BANK_NUM                       8
  27
  28 #define GPIO_BANK(gpio)                         ((gpio) >> 5)
  29 #define GPIO_BIT(gpio)                          ((gpio) & (GPIO_PER_BANK - 1))
  30
  31 /* There is a GPIO control register for each GPIO */
  32 #define GPIO_CONTROL(gpio)                      (0x00000100 + ((gpio) << 2))
  33
  34 /* The remaining registers are per GPIO bank */
  35 #define GPIO_OUT_STATUS(bank)                   (0x00000000 + ((bank) << 2))
  36 #define GPIO_IN_STATUS(bank)                    (0x00000020 + ((bank) << 2))
  37 #define GPIO_OUT_SET(bank)                      (0x00000040 + ((bank) << 2))
  38 #define GPIO_OUT_CLEAR(bank)                    (0x00000060 + ((bank) << 2))
  39 #define GPIO_INT_STATUS(bank)                   (0x00000080 + ((bank) << 2))
  40 #define GPIO_INT_MASK(bank)                     (0x000000a0 + ((bank) << 2))
  41 #define GPIO_INT_MSKCLR(bank)                   (0x000000c0 + ((bank) << 2))
  42 #define GPIO_PWD_STATUS(bank)                   (0x00000500 + ((bank) << 2))
  43
  44 #define GPIO_GPPWR_OFFSET                       0x00000520
  45
  46 #define GPIO_GPCTR0_DBR_SHIFT                   5
  47 #define GPIO_GPCTR0_DBR_MASK                    0x000001e0
  48
  49 #define GPIO_GPCTR0_ITR_SHIFT                   3
  50 #define GPIO_GPCTR0_ITR_MASK                    0x00000018
  51 #define GPIO_GPCTR0_ITR_CMD_RISING_EDGE         0x00000001
  52 #define GPIO_GPCTR0_ITR_CMD_FALLING_EDGE        0x00000002
  53 #define GPIO_GPCTR0_ITR_CMD_BOTH_EDGE           0x00000003
  54
  55 #define GPIO_GPCTR0_IOTR_MASK                   0x00000001
  56 #define GPIO_GPCTR0_IOTR_CMD_0UTPUT             0x00000000
  57 #define GPIO_GPCTR0_IOTR_CMD_INPUT              0x00000001
  58
  59 #define GPIO_GPCTR0_DB_ENABLE_MASK              0x00000100
  60
  61 #define LOCK_CODE                               0xffffffff
  62 #define UNLOCK_CODE                             0x00000000
  63
  64 struct bcm_kona_gpio {
  65         void __iomem *reg_base;
  66         int num_bank;
  67         spinlock_t lock;
  68         struct gpio_chip gpio_chip;
  69         struct irq_domain *irq_domain;
  70         struct bcm_kona_gpio_bank *banks;
  71         struct platform_device *pdev;
  72 };
  73
  74 struct bcm_kona_gpio_bank {
  75         int id;
  76         int irq;
  77         /* Used in the interrupt handler */
  78         struct bcm_kona_gpio *kona_gpio;
  79 };
  80
  81 static inline struct bcm_kona_gpio *to_kona_gpio(struct gpio_chip *chip)
  82 {
  83         return container_of(chip, struct bcm_kona_gpio, gpio_chip);
  84 }
  85
  86 static inline void bcm_kona_gpio_write_lock_regs(void __iomem *reg_base,
  87                                                 int bank_id, u32 lockcode)
  88 {
  89         writel(BCM_GPIO_PASSWD, reg_base + GPIO_GPPWR_OFFSET);
  90         writel(lockcode, reg_base + GPIO_PWD_STATUS(bank_id));
  91 }
  92
  93 static void bcm_kona_gpio_lock_gpio(struct bcm_kona_gpio *kona_gpio,
  94                                         unsigned gpio)
  95 {
  96         u32 val;
  97         unsigned long flags;
  98         int bank_id = GPIO_BANK(gpio);
  99
 100         spin_lock_irqsave(&kona_gpio->lock, flags);
 101
 102         val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
 103         val |= BIT(gpio);
 104         bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
 105
 106         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 107 }
 108
 109 static void bcm_kona_gpio_unlock_gpio(struct bcm_kona_gpio *kona_gpio,
 110                                         unsigned gpio)
 111 {
 112         u32 val;
 113         unsigned long flags;
 114         int bank_id = GPIO_BANK(gpio);
 115
 116         spin_lock_irqsave(&kona_gpio->lock, flags);
 117
 118         val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
 119         val &= ~BIT(gpio);
 120         bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
 121
 122         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 123 }
 124
 125 static int bcm_kona_gpio_get_dir(struct gpio_chip *chip, unsigned gpio)
 126 {
 127         struct bcm_kona_gpio *kona_gpio = to_kona_gpio(chip);
 128         void __iomem *reg_base = kona_gpio->reg_base;
 129         u32 val;
 130
 131         val = readl(reg_base + GPIO_CONTROL(gpio)) & GPIO_GPCTR0_IOTR_MASK;
 132         return val ? GPIOF_DIR_IN : GPIOF_DIR_OUT;
 133 }
 134
 135 static void bcm_kona_gpio_set(struct gpio_chip *chip, unsigned gpio, int value)
 136 {
 137         struct bcm_kona_gpio *kona_gpio;
 138         void __iomem *reg_base;
 139         int bank_id = GPIO_BANK(gpio);
 140         int bit = GPIO_BIT(gpio);
 141         u32 val, reg_offset;
 142         unsigned long flags;
 143
 144         kona_gpio = to_kona_gpio(chip);
 145         reg_base = kona_gpio->reg_base;
 146         spin_lock_irqsave(&kona_gpio->lock, flags);
 147
 148         /* this function only applies to output pin */
 149         if (bcm_kona_gpio_get_dir(chip, gpio) == GPIOF_DIR_IN)
 150                 goto out;
 151
 152         reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
 153
 154         val = readl(reg_base + reg_offset);
 155         val |= BIT(bit);
 156         writel(val, reg_base + reg_offset);
 157
 158 out:
 159         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 160 }
 161
 162 static int bcm_kona_gpio_get(struct gpio_chip *chip, unsigned gpio)
 163 {
 164         struct bcm_kona_gpio *kona_gpio;
 165         void __iomem *reg_base;
 166         int bank_id = GPIO_BANK(gpio);
 167         int bit = GPIO_BIT(gpio);
 168         u32 val, reg_offset;
 169         unsigned long flags;
 170
 171         kona_gpio = to_kona_gpio(chip);
 172         reg_base = kona_gpio->reg_base;
 173         spin_lock_irqsave(&kona_gpio->lock, flags);
 174
 175         if (bcm_kona_gpio_get_dir(chip, gpio) == GPIOF_DIR_IN)
 176                 reg_offset = GPIO_IN_STATUS(bank_id);
 177         else
 178                 reg_offset = GPIO_OUT_STATUS(bank_id);
 179
 180         /* read the GPIO bank status */
 181         val = readl(reg_base + reg_offset);
 182
 183         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 184
 185         /* return the specified bit status */
 186         return !!(val & BIT(bit));
 187 }
 188
 189 static int bcm_kona_gpio_request(struct gpio_chip *chip, unsigned gpio)
 190 {
 191         struct bcm_kona_gpio *kona_gpio = to_kona_gpio(chip);
 192
 193         bcm_kona_gpio_unlock_gpio(kona_gpio, gpio);
 194         return 0;
 195 }
 196
 197 static void bcm_kona_gpio_free(struct gpio_chip *chip, unsigned gpio)
 198 {
 199         struct bcm_kona_gpio *kona_gpio = to_kona_gpio(chip);
 200
 201         bcm_kona_gpio_lock_gpio(kona_gpio, gpio);
 202 }
 203
 204 static int bcm_kona_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
 205 {
 206         struct bcm_kona_gpio *kona_gpio;
 207         void __iomem *reg_base;
 208         u32 val;
 209         unsigned long flags;
 210
 211         kona_gpio = to_kona_gpio(chip);
 212         reg_base = kona_gpio->reg_base;
 213         spin_lock_irqsave(&kona_gpio->lock, flags);
 214
 215         val = readl(reg_base + GPIO_CONTROL(gpio));
 216         val &= ~GPIO_GPCTR0_IOTR_MASK;
 217         val |= GPIO_GPCTR0_IOTR_CMD_INPUT;
 218         writel(val, reg_base + GPIO_CONTROL(gpio));
 219
 220         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 221
 222         return 0;
 223 }
 224
 225 static int bcm_kona_gpio_direction_output(struct gpio_chip *chip,
 226                                           unsigned gpio, int value)
 227 {
 228         struct bcm_kona_gpio *kona_gpio;
 229         void __iomem *reg_base;
 230         int bank_id = GPIO_BANK(gpio);
 231         int bit = GPIO_BIT(gpio);
 232         u32 val, reg_offset;
 233         unsigned long flags;
 234
 235         kona_gpio = to_kona_gpio(chip);
 236         reg_base = kona_gpio->reg_base;
 237         spin_lock_irqsave(&kona_gpio->lock, flags);
 238
 239         val = readl(reg_base + GPIO_CONTROL(gpio));
 240         val &= ~GPIO_GPCTR0_IOTR_MASK;
 241         val |= GPIO_GPCTR0_IOTR_CMD_0UTPUT;
 242         writel(val, reg_base + GPIO_CONTROL(gpio));
 243         reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
 244
 245         val = readl(reg_base + reg_offset);
 246         val |= BIT(bit);
 247         writel(val, reg_base + reg_offset);
 248
 249         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 250
 251         return 0;
 252 }
 253
 254 static int bcm_kona_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
 255 {
 256         struct bcm_kona_gpio *kona_gpio;
 257
 258         kona_gpio = to_kona_gpio(chip);
 259         if (gpio >= kona_gpio->gpio_chip.ngpio)
 260                 return -ENXIO;
 261         return irq_create_mapping(kona_gpio->irq_domain, gpio);
 262 }
 263
 264 static int bcm_kona_gpio_set_debounce(struct gpio_chip *chip, unsigned gpio,
 265                                       unsigned debounce)
 266 {
 267         struct bcm_kona_gpio *kona_gpio;
 268         void __iomem *reg_base;
 269         u32 val, res;
 270         unsigned long flags;
 271
 272         kona_gpio = to_kona_gpio(chip);
 273         reg_base = kona_gpio->reg_base;
 274         /* debounce must be 1-128ms (or 0) */
 275         if ((debounce > 0 && debounce < 1000) || debounce > 128000) {
 276                 dev_err(chip->dev, "Debounce value %u not in range\n",
 277                         debounce);
 278                 return -EINVAL;
 279         }
 280
 281         /* calculate debounce bit value */
 282         if (debounce != 0) {
 283                 /* Convert to ms */
 284                 debounce /= 1000;
 285                 /* find the MSB */
 286                 res = fls(debounce) - 1;
 287                 /* Check if MSB-1 is set (round up or down) */
 288                 if (res > 0 && (debounce & BIT(res - 1)))
 289                         res++;
 290         }
 291
 292         /* spin lock for read-modify-write of the GPIO register */
 293         spin_lock_irqsave(&kona_gpio->lock, flags);
 294
 295         val = readl(reg_base + GPIO_CONTROL(gpio));
 296         val &= ~GPIO_GPCTR0_DBR_MASK;
 297
 298         if (debounce == 0) {
 299                 /* disable debounce */
 300                 val &= ~GPIO_GPCTR0_DB_ENABLE_MASK;
 301         } else {
 302                 val |= GPIO_GPCTR0_DB_ENABLE_MASK |
 303                     (res << GPIO_GPCTR0_DBR_SHIFT);
 304         }
 305
 306         writel(val, reg_base + GPIO_CONTROL(gpio));
 307
 308         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 309
 310         return 0;
 311 }
 312
 313 static struct gpio_chip template_chip = {
 314         .label = "bcm-kona-gpio",
 315         .owner = THIS_MODULE,
 316         .request = bcm_kona_gpio_request,
 317         .free = bcm_kona_gpio_free,
 318         .get_direction = bcm_kona_gpio_get_dir,
 319         .direction_input = bcm_kona_gpio_direction_input,
 320         .get = bcm_kona_gpio_get,
 321         .direction_output = bcm_kona_gpio_direction_output,
 322         .set = bcm_kona_gpio_set,
 323         .set_debounce = bcm_kona_gpio_set_debounce,
 324         .to_irq = bcm_kona_gpio_to_irq,
 325         .base = 0,
 326 };
 327
 328 static void bcm_kona_gpio_irq_ack(struct irq_data *d)
 329 {
 330         struct bcm_kona_gpio *kona_gpio;
 331         void __iomem *reg_base;
 332         unsigned gpio = d->hwirq;
 333         int bank_id = GPIO_BANK(gpio);
 334         int bit = GPIO_BIT(gpio);
 335         u32 val;
 336         unsigned long flags;
 337
 338         kona_gpio = irq_data_get_irq_chip_data(d);
 339         reg_base = kona_gpio->reg_base;
 340         spin_lock_irqsave(&kona_gpio->lock, flags);
 341
 342         val = readl(reg_base + GPIO_INT_STATUS(bank_id));
 343         val |= BIT(bit);
 344         writel(val, reg_base + GPIO_INT_STATUS(bank_id));
 345
 346         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 347 }
 348
 349 static void bcm_kona_gpio_irq_mask(struct irq_data *d)
 350 {
 351         struct bcm_kona_gpio *kona_gpio;
 352         void __iomem *reg_base;
 353         unsigned gpio = d->hwirq;
 354         int bank_id = GPIO_BANK(gpio);
 355         int bit = GPIO_BIT(gpio);
 356         u32 val;
 357         unsigned long flags;
 358
 359         kona_gpio = irq_data_get_irq_chip_data(d);
 360         reg_base = kona_gpio->reg_base;
 361         spin_lock_irqsave(&kona_gpio->lock, flags);
 362
 363         val = readl(reg_base + GPIO_INT_MASK(bank_id));
 364         val |= BIT(bit);
 365         writel(val, reg_base + GPIO_INT_MASK(bank_id));
 366
 367         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 368 }
 369
 370 static void bcm_kona_gpio_irq_unmask(struct irq_data *d)
 371 {
 372         struct bcm_kona_gpio *kona_gpio;
 373         void __iomem *reg_base;
 374         unsigned gpio = d->hwirq;
 375         int bank_id = GPIO_BANK(gpio);
 376         int bit = GPIO_BIT(gpio);
 377         u32 val;
 378         unsigned long flags;
 379
 380         kona_gpio = irq_data_get_irq_chip_data(d);
 381         reg_base = kona_gpio->reg_base;
 382         spin_lock_irqsave(&kona_gpio->lock, flags);
 383
 384         val = readl(reg_base + GPIO_INT_MSKCLR(bank_id));
 385         val |= BIT(bit);
 386         writel(val, reg_base + GPIO_INT_MSKCLR(bank_id));
 387
 388         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 389 }
 390
 391 static int bcm_kona_gpio_irq_set_type(struct irq_data *d, unsigned int type)
 392 {
 393         struct bcm_kona_gpio *kona_gpio;
 394         void __iomem *reg_base;
 395         unsigned gpio = d->hwirq;
 396         u32 lvl_type;
 397         u32 val;
 398         unsigned long flags;
 399
 400         kona_gpio = irq_data_get_irq_chip_data(d);
 401         reg_base = kona_gpio->reg_base;
 402         switch (type & IRQ_TYPE_SENSE_MASK) {
 403         case IRQ_TYPE_EDGE_RISING:
 404                 lvl_type = GPIO_GPCTR0_ITR_CMD_RISING_EDGE;
 405                 break;
 406
 407         case IRQ_TYPE_EDGE_FALLING:
 408                 lvl_type = GPIO_GPCTR0_ITR_CMD_FALLING_EDGE;
 409                 break;
 410
 411         case IRQ_TYPE_EDGE_BOTH:
 412                 lvl_type = GPIO_GPCTR0_ITR_CMD_BOTH_EDGE;
 413                 break;
 414
 415         case IRQ_TYPE_LEVEL_HIGH:
 416         case IRQ_TYPE_LEVEL_LOW:
 417                 /* BCM GPIO doesn't support level triggering */
 418         default:
 419                 dev_err(kona_gpio->gpio_chip.dev,
 420                         "Invalid BCM GPIO irq type 0x%x\n", type);
 421                 return -EINVAL;
 422         }
 423
 424         spin_lock_irqsave(&kona_gpio->lock, flags);
 425
 426         val = readl(reg_base + GPIO_CONTROL(gpio));
 427         val &= ~GPIO_GPCTR0_ITR_MASK;
 428         val |= lvl_type << GPIO_GPCTR0_ITR_SHIFT;
 429         writel(val, reg_base + GPIO_CONTROL(gpio));
 430
 431         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 432
 433         return 0;
 434 }
 435
 436 static void bcm_kona_gpio_irq_handler(struct irq_desc *desc)
 437 {
 438         void __iomem *reg_base;
 439         int bit, bank_id;
 440         unsigned long sta;
 441         struct bcm_kona_gpio_bank *bank = irq_desc_get_handler_data(desc);
 442         struct irq_chip *chip = irq_desc_get_chip(desc);
 443
 444         chained_irq_enter(chip, desc);
 445
 446         /*
 447          * For bank interrupts, we can't use chip_data to store the kona_gpio
 448          * pointer, since GIC needs it for its own purposes. Therefore, we get
 449          * our pointer from the bank structure.
 450          */
 451         reg_base = bank->kona_gpio->reg_base;
 452         bank_id = bank->id;
 453
 454         while ((sta = readl(reg_base + GPIO_INT_STATUS(bank_id)) &
 455                     (~(readl(reg_base + GPIO_INT_MASK(bank_id)))))) {
 456                 for_each_set_bit(bit, &sta, 32) {
 457                         int hwirq = GPIO_PER_BANK * bank_id + bit;
 458                         int child_irq =
 459                                 irq_find_mapping(bank->kona_gpio->irq_domain,
 460                                                  hwirq);
 461                         /*
 462                          * Clear interrupt before handler is called so we don't
 463                          * miss any interrupt occurred during executing them.
 464                          */
 465                         writel(readl(reg_base + GPIO_INT_STATUS(bank_id)) |
 466                                BIT(bit), reg_base + GPIO_INT_STATUS(bank_id));
 467                         /* Invoke interrupt handler */
 468                         generic_handle_irq(child_irq);
 469                 }
 470         }
 471
 472         chained_irq_exit(chip, desc);
 473 }
 474
 475 static int bcm_kona_gpio_irq_reqres(struct irq_data *d)
 476 {
 477         struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
 478
 479         if (gpiochip_lock_as_irq(&kona_gpio->gpio_chip, d->hwirq)) {
 480                 dev_err(kona_gpio->gpio_chip.dev,
 481                         "unable to lock HW IRQ %lu for IRQ\n",
 482                         d->hwirq);
 483                 return -EINVAL;
 484         }
 485         return 0;
 486 }
 487
 488 static void bcm_kona_gpio_irq_relres(struct irq_data *d)
 489 {
 490         struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
 491
 492         gpiochip_unlock_as_irq(&kona_gpio->gpio_chip, d->hwirq);
 493 }
 494
 495 static struct irq_chip bcm_gpio_irq_chip = {
 496         .name = "bcm-kona-gpio",
 497         .irq_ack = bcm_kona_gpio_irq_ack,
 498         .irq_mask = bcm_kona_gpio_irq_mask,
 499         .irq_unmask = bcm_kona_gpio_irq_unmask,
 500         .irq_set_type = bcm_kona_gpio_irq_set_type,
 501         .irq_request_resources = bcm_kona_gpio_irq_reqres,
 502         .irq_release_resources = bcm_kona_gpio_irq_relres,
 503 };
 504
 505 static struct of_device_id const bcm_kona_gpio_of_match[] = {
 506         { .compatible = "brcm,kona-gpio" },
 507         {}
 508 };
 509
 510 MODULE_DEVICE_TABLE(of, bcm_kona_gpio_of_match);
 511
 512 /*
 513  * This lock class tells lockdep that GPIO irqs are in a different
 514  * category than their parents, so it won't report false recursion.
 515  */
 516 static struct lock_class_key gpio_lock_class;
 517
 518 static int bcm_kona_gpio_irq_map(struct irq_domain *d, unsigned int irq,
 519                                  irq_hw_number_t hwirq)
 520 {
 521         int ret;
 522
 523         ret = irq_set_chip_data(irq, d->host_data);
 524         if (ret < 0)
 525                 return ret;
 526         irq_set_lockdep_class(irq, &gpio_lock_class);
 527         irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip, handle_simple_irq);
 528         irq_set_noprobe(irq);
 529
 530         return 0;
 531 }
 532
 533 static void bcm_kona_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
 534 {
 535         irq_set_chip_and_handler(irq, NULL, NULL);
 536         irq_set_chip_data(irq, NULL);
 537 }
 538
 539 static const struct irq_domain_ops bcm_kona_irq_ops = {
 540         .map = bcm_kona_gpio_irq_map,
 541         .unmap = bcm_kona_gpio_irq_unmap,
 542         .xlate = irq_domain_xlate_twocell,
 543 };
 544
 545 static void bcm_kona_gpio_reset(struct bcm_kona_gpio *kona_gpio)
 546 {
 547         void __iomem *reg_base;
 548         int i;
 549
 550         reg_base = kona_gpio->reg_base;
 551         /* disable interrupts and clear status */
 552         for (i = 0; i < kona_gpio->num_bank; i++) {
 553                 /* Unlock the entire bank first */
 554                 bcm_kona_gpio_write_lock_regs(reg_base, i, UNLOCK_CODE);
 555                 writel(0xffffffff, reg_base + GPIO_INT_MASK(i));
 556                 writel(0xffffffff, reg_base + GPIO_INT_STATUS(i));
 557                 /* Now re-lock the bank */
 558                 bcm_kona_gpio_write_lock_regs(reg_base, i, LOCK_CODE);
 559         }
 560 }
 561
 562 static int bcm_kona_gpio_probe(struct platform_device *pdev)
 563 {
 564         struct device *dev = &pdev->dev;
 565         const struct of_device_id *match;
 566         struct resource *res;
 567         struct bcm_kona_gpio_bank *bank;
 568         struct bcm_kona_gpio *kona_gpio;
 569         struct gpio_chip *chip;
 570         int ret;
 571         int i;
 572
 573         match = of_match_device(bcm_kona_gpio_of_match, dev);
 574         if (!match) {
 575                 dev_err(dev, "Failed to find gpio controller\n");
 576                 return -ENODEV;
 577         }
 578
 579         kona_gpio = devm_kzalloc(dev, sizeof(*kona_gpio), GFP_KERNEL);
 580         if (!kona_gpio)
 581                 return -ENOMEM;
 582
 583         kona_gpio->gpio_chip = template_chip;
 584         chip = &kona_gpio->gpio_chip;
 585         kona_gpio->num_bank = of_irq_count(dev->of_node);
 586         if (kona_gpio->num_bank == 0) {
 587                 dev_err(dev, "Couldn't determine # GPIO banks\n");
 588                 return -ENOENT;
 589         }
 590         if (kona_gpio->num_bank > GPIO_MAX_BANK_NUM) {
 591                 dev_err(dev, "Too many GPIO banks configured (max=%d)\n",
 592                         GPIO_MAX_BANK_NUM);
 593                 return -ENXIO;
 594         }
 595         kona_gpio->banks = devm_kzalloc(dev,
 596                                         kona_gpio->num_bank *
 597                                         sizeof(*kona_gpio->banks), GFP_KERNEL);
 598         if (!kona_gpio->banks)
 599                 return -ENOMEM;
 600
 601         kona_gpio->pdev = pdev;
 602         platform_set_drvdata(pdev, kona_gpio);
 603         chip->of_node = dev->of_node;
 604         chip->ngpio = kona_gpio->num_bank * GPIO_PER_BANK;
 605
 606         kona_gpio->irq_domain = irq_domain_add_linear(dev->of_node,
 607                                                       chip->ngpio,
 608                                                       &bcm_kona_irq_ops,
 609                                                       kona_gpio);
 610         if (!kona_gpio->irq_domain) {
 611                 dev_err(dev, "Couldn't allocate IRQ domain\n");
 612                 return -ENXIO;
 613         }
 614
 615         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 616         kona_gpio->reg_base = devm_ioremap_resource(dev, res);
 617         if (IS_ERR(kona_gpio->reg_base)) {
 618                 ret = -ENXIO;
 619                 goto err_irq_domain;
 620         }
 621
 622         for (i = 0; i < kona_gpio->num_bank; i++) {
 623                 bank = &kona_gpio->banks[i];
 624                 bank->id = i;
 625                 bank->irq = platform_get_irq(pdev, i);
 626                 bank->kona_gpio = kona_gpio;
 627                 if (bank->irq < 0) {
 628                         dev_err(dev, "Couldn't get IRQ for bank %d", i);
 629                         ret = -ENOENT;
 630                         goto err_irq_domain;
 631                 }
 632         }
 633
 634         dev_info(&pdev->dev, "Setting up Kona GPIO\n");
 635
 636         bcm_kona_gpio_reset(kona_gpio);
 637
 638         ret = gpiochip_add(chip);
 639         if (ret < 0) {
 640                 dev_err(dev, "Couldn't add GPIO chip -- %d\n", ret);
 641                 goto err_irq_domain;
 642         }
 643         for (i = 0; i < kona_gpio->num_bank; i++) {
 644                 bank = &kona_gpio->banks[i];
 645                 irq_set_chained_handler_and_data(bank->irq,
 646                                                  bcm_kona_gpio_irq_handler,
 647                                                  bank);
 648         }
 649
 650         spin_lock_init(&kona_gpio->lock);
 651
 652         return 0;
 653
 654 err_irq_domain:
 655         irq_domain_remove(kona_gpio->irq_domain);
 656
 657         return ret;
 658 }
 659
 660 static struct platform_driver bcm_kona_gpio_driver = {
 661         .driver = {
 662                         .name = "bcm-kona-gpio",
 663                         .of_match_table = bcm_kona_gpio_of_match,
 664         },
 665         .probe = bcm_kona_gpio_probe,
 666 };
 667
 668 module_platform_driver(bcm_kona_gpio_driver);
 669
 670 MODULE_AUTHOR("Broadcom Corporation <bcm-kernel-feedback-list@broadcom.com>");
 671 MODULE_DESCRIPTION("Broadcom Kona GPIO Driver");
 672 MODULE_LICENSE("GPL v2");