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 void bcm_kona_gpio_set(struct gpio_chip *chip, unsigned gpio, int value)
 126 {
 127         struct bcm_kona_gpio *kona_gpio;
 128         void __iomem *reg_base;
 129         int bank_id = GPIO_BANK(gpio);
 130         int bit = GPIO_BIT(gpio);
 131         u32 val, reg_offset;
 132         unsigned long flags;
 133
 134         kona_gpio = to_kona_gpio(chip);
 135         reg_base = kona_gpio->reg_base;
 136         spin_lock_irqsave(&kona_gpio->lock, flags);
 137
 138         /* determine the GPIO pin direction */
 139         val = readl(reg_base + GPIO_CONTROL(gpio));
 140         val &= GPIO_GPCTR0_IOTR_MASK;
 141
 142         /* this function only applies to output pin */
 143         if (GPIO_GPCTR0_IOTR_CMD_INPUT == val)
 144                 goto out;
 145
 146         reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
 147
 148         val = readl(reg_base + reg_offset);
 149         val |= BIT(bit);
 150         writel(val, reg_base + reg_offset);
 151
 152 out:
 153         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 154 }
 155
 156 static int bcm_kona_gpio_get(struct gpio_chip *chip, unsigned gpio)
 157 {
 158         struct bcm_kona_gpio *kona_gpio;
 159         void __iomem *reg_base;
 160         int bank_id = GPIO_BANK(gpio);
 161         int bit = GPIO_BIT(gpio);
 162         u32 val, reg_offset;
 163         unsigned long flags;
 164
 165         kona_gpio = to_kona_gpio(chip);
 166         reg_base = kona_gpio->reg_base;
 167         spin_lock_irqsave(&kona_gpio->lock, flags);
 168
 169         /* determine the GPIO pin direction */
 170         val = readl(reg_base + GPIO_CONTROL(gpio));
 171         val &= GPIO_GPCTR0_IOTR_MASK;
 172
 173         /* read the GPIO bank status */
 174         reg_offset = (GPIO_GPCTR0_IOTR_CMD_INPUT == val) ?
 175             GPIO_IN_STATUS(bank_id) : GPIO_OUT_STATUS(bank_id);
 176         val = readl(reg_base + reg_offset);
 177
 178         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 179
 180         /* return the specified bit status */
 181         return !!(val & BIT(bit));
 182 }
 183
 184 static int bcm_kona_gpio_request(struct gpio_chip *chip, unsigned gpio)
 185 {
 186         struct bcm_kona_gpio *kona_gpio = to_kona_gpio(chip);
 187
 188         bcm_kona_gpio_unlock_gpio(kona_gpio, gpio);
 189         return 0;
 190 }
 191
 192 static void bcm_kona_gpio_free(struct gpio_chip *chip, unsigned gpio)
 193 {
 194         struct bcm_kona_gpio *kona_gpio = to_kona_gpio(chip);
 195
 196         bcm_kona_gpio_lock_gpio(kona_gpio, gpio);
 197 }
 198
 199 static int bcm_kona_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
 200 {
 201         struct bcm_kona_gpio *kona_gpio;
 202         void __iomem *reg_base;
 203         u32 val;
 204         unsigned long flags;
 205
 206         kona_gpio = to_kona_gpio(chip);
 207         reg_base = kona_gpio->reg_base;
 208         spin_lock_irqsave(&kona_gpio->lock, flags);
 209
 210         val = readl(reg_base + GPIO_CONTROL(gpio));
 211         val &= ~GPIO_GPCTR0_IOTR_MASK;
 212         val |= GPIO_GPCTR0_IOTR_CMD_INPUT;
 213         writel(val, reg_base + GPIO_CONTROL(gpio));
 214
 215         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 216
 217         return 0;
 218 }
 219
 220 static int bcm_kona_gpio_direction_output(struct gpio_chip *chip,
 221                                           unsigned gpio, int value)
 222 {
 223         struct bcm_kona_gpio *kona_gpio;
 224         void __iomem *reg_base;
 225         int bank_id = GPIO_BANK(gpio);
 226         int bit = GPIO_BIT(gpio);
 227         u32 val, reg_offset;
 228         unsigned long flags;
 229
 230         kona_gpio = to_kona_gpio(chip);
 231         reg_base = kona_gpio->reg_base;
 232         spin_lock_irqsave(&kona_gpio->lock, flags);
 233
 234         val = readl(reg_base + GPIO_CONTROL(gpio));
 235         val &= ~GPIO_GPCTR0_IOTR_MASK;
 236         val |= GPIO_GPCTR0_IOTR_CMD_0UTPUT;
 237         writel(val, reg_base + GPIO_CONTROL(gpio));
 238         reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
 239
 240         val = readl(reg_base + reg_offset);
 241         val |= BIT(bit);
 242         writel(val, reg_base + reg_offset);
 243
 244         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 245
 246         return 0;
 247 }
 248
 249 static int bcm_kona_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
 250 {
 251         struct bcm_kona_gpio *kona_gpio;
 252
 253         kona_gpio = to_kona_gpio(chip);
 254         if (gpio >= kona_gpio->gpio_chip.ngpio)
 255                 return -ENXIO;
 256         return irq_create_mapping(kona_gpio->irq_domain, gpio);
 257 }
 258
 259 static int bcm_kona_gpio_set_debounce(struct gpio_chip *chip, unsigned gpio,
 260                                       unsigned debounce)
 261 {
 262         struct bcm_kona_gpio *kona_gpio;
 263         void __iomem *reg_base;
 264         u32 val, res;
 265         unsigned long flags;
 266
 267         kona_gpio = to_kona_gpio(chip);
 268         reg_base = kona_gpio->reg_base;
 269         /* debounce must be 1-128ms (or 0) */
 270         if ((debounce > 0 && debounce < 1000) || debounce > 128000) {
 271                 dev_err(chip->dev, "Debounce value %u not in range\n",
 272                         debounce);
 273                 return -EINVAL;
 274         }
 275
 276         /* calculate debounce bit value */
 277         if (debounce != 0) {
 278                 /* Convert to ms */
 279                 debounce /= 1000;
 280                 /* find the MSB */
 281                 res = fls(debounce) - 1;
 282                 /* Check if MSB-1 is set (round up or down) */
 283                 if (res > 0 && (debounce & BIT(res - 1)))
 284                         res++;
 285         }
 286
 287         /* spin lock for read-modify-write of the GPIO register */
 288         spin_lock_irqsave(&kona_gpio->lock, flags);
 289
 290         val = readl(reg_base + GPIO_CONTROL(gpio));
 291         val &= ~GPIO_GPCTR0_DBR_MASK;
 292
 293         if (debounce == 0) {
 294                 /* disable debounce */
 295                 val &= ~GPIO_GPCTR0_DB_ENABLE_MASK;
 296         } else {
 297                 val |= GPIO_GPCTR0_DB_ENABLE_MASK |
 298                     (res << GPIO_GPCTR0_DBR_SHIFT);
 299         }
 300
 301         writel(val, reg_base + GPIO_CONTROL(gpio));
 302
 303         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 304
 305         return 0;
 306 }
 307
 308 static struct gpio_chip template_chip = {
 309         .label = "bcm-kona-gpio",
 310         .owner = THIS_MODULE,
 311         .request = bcm_kona_gpio_request,
 312         .free = bcm_kona_gpio_free,
 313         .direction_input = bcm_kona_gpio_direction_input,
 314         .get = bcm_kona_gpio_get,
 315         .direction_output = bcm_kona_gpio_direction_output,
 316         .set = bcm_kona_gpio_set,
 317         .set_debounce = bcm_kona_gpio_set_debounce,
 318         .to_irq = bcm_kona_gpio_to_irq,
 319         .base = 0,
 320 };
 321
 322 static void bcm_kona_gpio_irq_ack(struct irq_data *d)
 323 {
 324         struct bcm_kona_gpio *kona_gpio;
 325         void __iomem *reg_base;
 326         unsigned gpio = d->hwirq;
 327         int bank_id = GPIO_BANK(gpio);
 328         int bit = GPIO_BIT(gpio);
 329         u32 val;
 330         unsigned long flags;
 331
 332         kona_gpio = irq_data_get_irq_chip_data(d);
 333         reg_base = kona_gpio->reg_base;
 334         spin_lock_irqsave(&kona_gpio->lock, flags);
 335
 336         val = readl(reg_base + GPIO_INT_STATUS(bank_id));
 337         val |= BIT(bit);
 338         writel(val, reg_base + GPIO_INT_STATUS(bank_id));
 339
 340         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 341 }
 342
 343 static void bcm_kona_gpio_irq_mask(struct irq_data *d)
 344 {
 345         struct bcm_kona_gpio *kona_gpio;
 346         void __iomem *reg_base;
 347         unsigned gpio = d->hwirq;
 348         int bank_id = GPIO_BANK(gpio);
 349         int bit = GPIO_BIT(gpio);
 350         u32 val;
 351         unsigned long flags;
 352
 353         kona_gpio = irq_data_get_irq_chip_data(d);
 354         reg_base = kona_gpio->reg_base;
 355         spin_lock_irqsave(&kona_gpio->lock, flags);
 356
 357         val = readl(reg_base + GPIO_INT_MASK(bank_id));
 358         val |= BIT(bit);
 359         writel(val, reg_base + GPIO_INT_MASK(bank_id));
 360
 361         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 362 }
 363
 364 static void bcm_kona_gpio_irq_unmask(struct irq_data *d)
 365 {
 366         struct bcm_kona_gpio *kona_gpio;
 367         void __iomem *reg_base;
 368         unsigned gpio = d->hwirq;
 369         int bank_id = GPIO_BANK(gpio);
 370         int bit = GPIO_BIT(gpio);
 371         u32 val;
 372         unsigned long flags;
 373
 374         kona_gpio = irq_data_get_irq_chip_data(d);
 375         reg_base = kona_gpio->reg_base;
 376         spin_lock_irqsave(&kona_gpio->lock, flags);
 377
 378         val = readl(reg_base + GPIO_INT_MSKCLR(bank_id));
 379         val |= BIT(bit);
 380         writel(val, reg_base + GPIO_INT_MSKCLR(bank_id));
 381
 382         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 383 }
 384
 385 static int bcm_kona_gpio_irq_set_type(struct irq_data *d, unsigned int type)
 386 {
 387         struct bcm_kona_gpio *kona_gpio;
 388         void __iomem *reg_base;
 389         unsigned gpio = d->hwirq;
 390         u32 lvl_type;
 391         u32 val;
 392         unsigned long flags;
 393
 394         kona_gpio = irq_data_get_irq_chip_data(d);
 395         reg_base = kona_gpio->reg_base;
 396         switch (type & IRQ_TYPE_SENSE_MASK) {
 397         case IRQ_TYPE_EDGE_RISING:
 398                 lvl_type = GPIO_GPCTR0_ITR_CMD_RISING_EDGE;
 399                 break;
 400
 401         case IRQ_TYPE_EDGE_FALLING:
 402                 lvl_type = GPIO_GPCTR0_ITR_CMD_FALLING_EDGE;
 403                 break;
 404
 405         case IRQ_TYPE_EDGE_BOTH:
 406                 lvl_type = GPIO_GPCTR0_ITR_CMD_BOTH_EDGE;
 407                 break;
 408
 409         case IRQ_TYPE_LEVEL_HIGH:
 410         case IRQ_TYPE_LEVEL_LOW:
 411                 /* BCM GPIO doesn't support level triggering */
 412         default:
 413                 dev_err(kona_gpio->gpio_chip.dev,
 414                         "Invalid BCM GPIO irq type 0x%x\n", type);
 415                 return -EINVAL;
 416         }
 417
 418         spin_lock_irqsave(&kona_gpio->lock, flags);
 419
 420         val = readl(reg_base + GPIO_CONTROL(gpio));
 421         val &= ~GPIO_GPCTR0_ITR_MASK;
 422         val |= lvl_type << GPIO_GPCTR0_ITR_SHIFT;
 423         writel(val, reg_base + GPIO_CONTROL(gpio));
 424
 425         spin_unlock_irqrestore(&kona_gpio->lock, flags);
 426
 427         return 0;
 428 }
 429
 430 static void bcm_kona_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
 431 {
 432         void __iomem *reg_base;
 433         int bit, bank_id;
 434         unsigned long sta;
 435         struct bcm_kona_gpio_bank *bank = irq_get_handler_data(irq);
 436         struct irq_chip *chip = irq_desc_get_chip(desc);
 437
 438         chained_irq_enter(chip, desc);
 439
 440         /*
 441          * For bank interrupts, we can't use chip_data to store the kona_gpio
 442          * pointer, since GIC needs it for its own purposes. Therefore, we get
 443          * our pointer from the bank structure.
 444          */
 445         reg_base = bank->kona_gpio->reg_base;
 446         bank_id = bank->id;
 447
 448         while ((sta = readl(reg_base + GPIO_INT_STATUS(bank_id)) &
 449                     (~(readl(reg_base + GPIO_INT_MASK(bank_id)))))) {
 450                 for_each_set_bit(bit, &sta, 32) {
 451                         int hwirq = GPIO_PER_BANK * bank_id + bit;
 452                         int child_irq =
 453                                 irq_find_mapping(bank->kona_gpio->irq_domain,
 454                                                  hwirq);
 455                         /*
 456                          * Clear interrupt before handler is called so we don't
 457                          * miss any interrupt occurred during executing them.
 458                          */
 459                         writel(readl(reg_base + GPIO_INT_STATUS(bank_id)) |
 460                                BIT(bit), reg_base + GPIO_INT_STATUS(bank_id));
 461                         /* Invoke interrupt handler */
 462                         generic_handle_irq(child_irq);
 463                 }
 464         }
 465
 466         chained_irq_exit(chip, desc);
 467 }
 468
 469 static int bcm_kona_gpio_irq_reqres(struct irq_data *d)
 470 {
 471         struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
 472
 473         if (gpiochip_lock_as_irq(&kona_gpio->gpio_chip, d->hwirq)) {
 474                 dev_err(kona_gpio->gpio_chip.dev,
 475                         "unable to lock HW IRQ %lu for IRQ\n",
 476                         d->hwirq);
 477                 return -EINVAL;
 478         }
 479         return 0;
 480 }
 481
 482 static void bcm_kona_gpio_irq_relres(struct irq_data *d)
 483 {
 484         struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
 485
 486         gpiochip_unlock_as_irq(&kona_gpio->gpio_chip, d->hwirq);
 487 }
 488
 489 static struct irq_chip bcm_gpio_irq_chip = {
 490         .name = "bcm-kona-gpio",
 491         .irq_ack = bcm_kona_gpio_irq_ack,
 492         .irq_mask = bcm_kona_gpio_irq_mask,
 493         .irq_unmask = bcm_kona_gpio_irq_unmask,
 494         .irq_set_type = bcm_kona_gpio_irq_set_type,
 495         .irq_request_resources = bcm_kona_gpio_irq_reqres,
 496         .irq_release_resources = bcm_kona_gpio_irq_relres,
 497 };
 498
 499 static struct of_device_id const bcm_kona_gpio_of_match[] = {
 500         { .compatible = "brcm,kona-gpio" },
 501         {}
 502 };
 503
 504 MODULE_DEVICE_TABLE(of, bcm_kona_gpio_of_match);
 505
 506 /*
 507  * This lock class tells lockdep that GPIO irqs are in a different
 508  * category than their parents, so it won't report false recursion.
 509  */
 510 static struct lock_class_key gpio_lock_class;
 511
 512 static int bcm_kona_gpio_irq_map(struct irq_domain *d, unsigned int irq,
 513                                  irq_hw_number_t hwirq)
 514 {
 515         int ret;
 516
 517         ret = irq_set_chip_data(irq, d->host_data);
 518         if (ret < 0)
 519                 return ret;
 520         irq_set_lockdep_class(irq, &gpio_lock_class);
 521         irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip, handle_simple_irq);
 522 #ifdef CONFIG_ARM
 523         set_irq_flags(irq, IRQF_VALID);
 524 #else
 525         irq_set_noprobe(irq);
 526 #endif
 527
 528         return 0;
 529 }
 530
 531 static void bcm_kona_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
 532 {
 533         irq_set_chip_and_handler(irq, NULL, NULL);
 534         irq_set_chip_data(irq, NULL);
 535 }
 536
 537 static struct irq_domain_ops bcm_kona_irq_ops = {
 538         .map = bcm_kona_gpio_irq_map,
 539         .unmap = bcm_kona_gpio_irq_unmap,
 540         .xlate = irq_domain_xlate_twocell,
 541 };
 542
 543 static void bcm_kona_gpio_reset(struct bcm_kona_gpio *kona_gpio)
 544 {
 545         void __iomem *reg_base;
 546         int i;
 547
 548         reg_base = kona_gpio->reg_base;
 549         /* disable interrupts and clear status */
 550         for (i = 0; i < kona_gpio->num_bank; i++) {
 551                 /* Unlock the entire bank first */
 552                 bcm_kona_gpio_write_lock_regs(kona_gpio, i, UNLOCK_CODE);
 553                 writel(0xffffffff, reg_base + GPIO_INT_MASK(i));
 554                 writel(0xffffffff, reg_base + GPIO_INT_STATUS(i));
 555                 /* Now re-lock the bank */
 556                 bcm_kona_gpio_write_lock_regs(kona_gpio, i, LOCK_CODE);
 557         }
 558 }
 559
 560 static int bcm_kona_gpio_probe(struct platform_device *pdev)
 561 {
 562         struct device *dev = &pdev->dev;
 563         const struct of_device_id *match;
 564         struct resource *res;
 565         struct bcm_kona_gpio_bank *bank;
 566         struct bcm_kona_gpio *kona_gpio;
 567         struct gpio_chip *chip;
 568         int ret;
 569         int i;
 570
 571         match = of_match_device(bcm_kona_gpio_of_match, dev);
 572         if (!match) {
 573                 dev_err(dev, "Failed to find gpio controller\n");
 574                 return -ENODEV;
 575         }
 576
 577         kona_gpio = devm_kzalloc(dev, sizeof(*kona_gpio), GFP_KERNEL);
 578         if (!kona_gpio)
 579                 return -ENOMEM;
 580
 581         kona_gpio->gpio_chip = template_chip;
 582         chip = &kona_gpio->gpio_chip;
 583         kona_gpio->num_bank = of_irq_count(dev->of_node);
 584         if (kona_gpio->num_bank == 0) {
 585                 dev_err(dev, "Couldn't determine # GPIO banks\n");
 586                 return -ENOENT;
 587         }
 588         if (kona_gpio->num_bank > GPIO_MAX_BANK_NUM) {
 589                 dev_err(dev, "Too many GPIO banks configured (max=%d)\n",
 590                         GPIO_MAX_BANK_NUM);
 591                 return -ENXIO;
 592         }
 593         kona_gpio->banks = devm_kzalloc(dev,
 594                                         kona_gpio->num_bank *
 595                                         sizeof(*kona_gpio->banks), GFP_KERNEL);
 596         if (!kona_gpio->banks)
 597                 return -ENOMEM;
 598
 599         kona_gpio->pdev = pdev;
 600         platform_set_drvdata(pdev, kona_gpio);
 601         chip->of_node = dev->of_node;
 602         chip->ngpio = kona_gpio->num_bank * GPIO_PER_BANK;
 603
 604         kona_gpio->irq_domain = irq_domain_add_linear(dev->of_node,
 605                                                       chip->ngpio,
 606                                                       &bcm_kona_irq_ops,
 607                                                       kona_gpio);
 608         if (!kona_gpio->irq_domain) {
 609                 dev_err(dev, "Couldn't allocate IRQ domain\n");
 610                 return -ENXIO;
 611         }
 612
 613         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 614         kona_gpio->reg_base = devm_ioremap_resource(dev, res);
 615         if (IS_ERR(kona_gpio->reg_base)) {
 616                 ret = -ENXIO;
 617                 goto err_irq_domain;
 618         }
 619
 620         for (i = 0; i < kona_gpio->num_bank; i++) {
 621                 bank = &kona_gpio->banks[i];
 622                 bank->id = i;
 623                 bank->irq = platform_get_irq(pdev, i);
 624                 bank->kona_gpio = kona_gpio;
 625                 if (bank->irq < 0) {
 626                         dev_err(dev, "Couldn't get IRQ for bank %d", i);
 627                         ret = -ENOENT;
 628                         goto err_irq_domain;
 629                 }
 630         }
 631
 632         dev_info(&pdev->dev, "Setting up Kona GPIO\n");
 633
 634         bcm_kona_gpio_reset(kona_gpio);
 635
 636         ret = gpiochip_add(chip);
 637         if (ret < 0) {
 638                 dev_err(dev, "Couldn't add GPIO chip -- %d\n", ret);
 639                 goto err_irq_domain;
 640         }
 641         for (i = 0; i < chip->ngpio; i++) {
 642                 int irq = bcm_kona_gpio_to_irq(chip, i);
 643                 irq_set_lockdep_class(irq, &gpio_lock_class);
 644                 irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip,
 645                                          handle_simple_irq);
 646 #ifdef CONFIG_ARM
 647                 set_irq_flags(irq, IRQF_VALID);
 648 #else
 649                 irq_set_noprobe(irq);
 650 #endif
 651         }
 652         for (i = 0; i < kona_gpio->num_bank; i++) {
 653                 bank = &kona_gpio->banks[i];
 654                 irq_set_chained_handler(bank->irq, bcm_kona_gpio_irq_handler);
 655                 irq_set_handler_data(bank->irq, bank);
 656         }
 657
 658         spin_lock_init(&kona_gpio->lock);
 659
 660         return 0;
 661
 662 err_irq_domain:
 663         irq_domain_remove(kona_gpio->irq_domain);
 664
 665         return ret;
 666 }
 667
 668 static struct platform_driver bcm_kona_gpio_driver = {
 669         .driver = {
 670                         .name = "bcm-kona-gpio",
 671                         .of_match_table = bcm_kona_gpio_of_match,
 672         },
 673         .probe = bcm_kona_gpio_probe,
 674 };
 675
 676 module_platform_driver(bcm_kona_gpio_driver);
 677
 678 MODULE_AUTHOR("Broadcom Corporation <bcm-kernel-feedback-list@broadcom.com>");
 679 MODULE_DESCRIPTION("Broadcom Kona GPIO Driver");
 680 MODULE_LICENSE("GPL v2");