drivers/gpio/gpio-bcm-kona.c

   1 /*
   2  * Broadcom Kona GPIO Driver
   3  *
   4  * Author: Broadcom Corporation <bcm-kernel-feedback-list@broadcom.com>
   5  * Copyright (C) 2012-2014 Broadcom Corporation
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License as
   9  * published by the Free Software Foundation version 2.
  10  *
  11  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  12  * kind, whether express or implied; without even the implied warranty
  13  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  */
  16
  17 #include <linux/bitops.h>
  18 #include <linux/err.h>
  19 #include <linux/io.h>
  20 #include <linux/gpio/driver.h>
  21 #include <linux/of_device.h>
  22 #include <linux/init.h>
  23 #include <linux/irqdomain.h>
  24 #include <linux/irqchip/chained_irq.h>
  25
  26 #define BCM_GPIO_PASSWD                         0x00a5a501
  27 #define GPIO_PER_BANK                           32
  28 #define GPIO_MAX_BANK_NUM                       8
  29
  30 #define GPIO_BANK(gpio)                         ((gpio) >> 5)
  31 #define GPIO_BIT(gpio)                          ((gpio) & (GPIO_PER_BANK - 1))
  32
  33 /* There is a GPIO control register for each GPIO */
  34 #define GPIO_CONTROL(gpio)                      (0x00000100 + ((gpio) << 2))
  35
  36 /* The remaining registers are per GPIO bank */
  37 #define GPIO_OUT_STATUS(bank)                   (0x00000000 + ((bank) << 2))
  38 #define GPIO_IN_STATUS(bank)                    (0x00000020 + ((bank) << 2))
  39 #define GPIO_OUT_SET(bank)                      (0x00000040 + ((bank) << 2))
  40 #define GPIO_OUT_CLEAR(bank)                    (0x00000060 + ((bank) << 2))
  41 #define GPIO_INT_STATUS(bank)                   (0x00000080 + ((bank) << 2))
  42 #define GPIO_INT_MASK(bank)                     (0x000000a0 + ((bank) << 2))
  43 #define GPIO_INT_MSKCLR(bank)                   (0x000000c0 + ((bank) << 2))
  44 #define GPIO_PWD_STATUS(bank)                   (0x00000500 + ((bank) << 2))
  45
  46 #define GPIO_GPPWR_OFFSET                       0x00000520
  47
  48 #define GPIO_GPCTR0_DBR_SHIFT                   5
  49 #define GPIO_GPCTR0_DBR_MASK                    0x000001e0
  50
  51 #define GPIO_GPCTR0_ITR_SHIFT                   3
  52 #define GPIO_GPCTR0_ITR_MASK                    0x00000018
  53 #define GPIO_GPCTR0_ITR_CMD_RISING_EDGE         0x00000001
  54 #define GPIO_GPCTR0_ITR_CMD_FALLING_EDGE        0x00000002
  55 #define GPIO_GPCTR0_ITR_CMD_BOTH_EDGE           0x00000003
  56
  57 #define GPIO_GPCTR0_IOTR_MASK                   0x00000001
  58 #define GPIO_GPCTR0_IOTR_CMD_0UTPUT             0x00000000
  59 #define GPIO_GPCTR0_IOTR_CMD_INPUT              0x00000001
  60
  61 #define GPIO_GPCTR0_DB_ENABLE_MASK              0x00000100
  62
  63 #define LOCK_CODE                               0xffffffff
  64 #define UNLOCK_CODE                             0x00000000
  65
  66 struct bcm_kona_gpio {
  67         void __iomem *reg_base;
  68         int num_bank;
  69         raw_spinlock_t lock;
  70         struct gpio_chip gpio_chip;
  71         struct irq_domain *irq_domain;
  72         struct bcm_kona_gpio_bank *banks;
  73         struct platform_device *pdev;
  74 };
  75
  76 struct bcm_kona_gpio_bank {
  77         int id;
  78         int irq;
  79         /* Used in the interrupt handler */
  80         struct bcm_kona_gpio *kona_gpio;
  81 };
  82
  83 static inline void bcm_kona_gpio_write_lock_regs(void __iomem *reg_base,
  84                                                 int bank_id, u32 lockcode)
  85 {
  86         writel(BCM_GPIO_PASSWD, reg_base + GPIO_GPPWR_OFFSET);
  87         writel(lockcode, reg_base + GPIO_PWD_STATUS(bank_id));
  88 }
  89
  90 static void bcm_kona_gpio_lock_gpio(struct bcm_kona_gpio *kona_gpio,
  91                                         unsigned gpio)
  92 {
  93         u32 val;
  94         unsigned long flags;
  95         int bank_id = GPIO_BANK(gpio);
  96
  97         raw_spin_lock_irqsave(&kona_gpio->lock, flags);
  98
  99         val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
 100         val |= BIT(gpio);
 101         bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
 102
 103         raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 104 }
 105
 106 static void bcm_kona_gpio_unlock_gpio(struct bcm_kona_gpio *kona_gpio,
 107                                         unsigned gpio)
 108 {
 109         u32 val;
 110         unsigned long flags;
 111         int bank_id = GPIO_BANK(gpio);
 112
 113         raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 114
 115         val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
 116         val &= ~BIT(gpio);
 117         bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
 118
 119         raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 120 }
 121
 122 static int bcm_kona_gpio_get_dir(struct gpio_chip *chip, unsigned gpio)
 123 {
 124         struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
 125         void __iomem *reg_base = kona_gpio->reg_base;
 126         u32 val;
 127
 128         val = readl(reg_base + GPIO_CONTROL(gpio)) & GPIO_GPCTR0_IOTR_MASK;
 129         return val ? GPIO_LINE_DIRECTION_IN : GPIO_LINE_DIRECTION_OUT;
 130 }
 131
 132 static void bcm_kona_gpio_set(struct gpio_chip *chip, unsigned gpio, int value)
 133 {
 134         struct bcm_kona_gpio *kona_gpio;
 135         void __iomem *reg_base;
 136         int bank_id = GPIO_BANK(gpio);
 137         int bit = GPIO_BIT(gpio);
 138         u32 val, reg_offset;
 139         unsigned long flags;
 140
 141         kona_gpio = gpiochip_get_data(chip);
 142         reg_base = kona_gpio->reg_base;
 143         raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 144
 145         /* this function only applies to output pin */
 146         if (bcm_kona_gpio_get_dir(chip, gpio) == GPIO_LINE_DIRECTION_IN)
 147                 goto out;
 148
 149         reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
 150
 151         val = readl(reg_base + reg_offset);
 152         val |= BIT(bit);
 153         writel(val, reg_base + reg_offset);
 154
 155 out:
 156         raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 157 }
 158
 159 static int bcm_kona_gpio_get(struct gpio_chip *chip, unsigned gpio)
 160 {
 161         struct bcm_kona_gpio *kona_gpio;
 162         void __iomem *reg_base;
 163         int bank_id = GPIO_BANK(gpio);
 164         int bit = GPIO_BIT(gpio);
 165         u32 val, reg_offset;
 166         unsigned long flags;
 167
 168         kona_gpio = gpiochip_get_data(chip);
 169         reg_base = kona_gpio->reg_base;
 170         raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 171
 172         if (bcm_kona_gpio_get_dir(chip, gpio) == GPIO_LINE_DIRECTION_IN)
 173                 reg_offset = GPIO_IN_STATUS(bank_id);
 174         else
 175                 reg_offset = GPIO_OUT_STATUS(bank_id);
 176
 177         /* read the GPIO bank status */
 178         val = readl(reg_base + reg_offset);
 179
 180         raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 181
 182         /* return the specified bit status */
 183         return !!(val & BIT(bit));
 184 }
 185
 186 static int bcm_kona_gpio_request(struct gpio_chip *chip, unsigned gpio)
 187 {
 188         struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
 189
 190         bcm_kona_gpio_unlock_gpio(kona_gpio, gpio);
 191         return 0;
 192 }
 193
 194 static void bcm_kona_gpio_free(struct gpio_chip *chip, unsigned gpio)
 195 {
 196         struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
 197
 198         bcm_kona_gpio_lock_gpio(kona_gpio, gpio);
 199 }
 200
 201 static int bcm_kona_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
 202 {
 203         struct bcm_kona_gpio *kona_gpio;
 204         void __iomem *reg_base;
 205         u32 val;
 206         unsigned long flags;
 207
 208         kona_gpio = gpiochip_get_data(chip);
 209         reg_base = kona_gpio->reg_base;
 210         raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 211
 212         val = readl(reg_base + GPIO_CONTROL(gpio));
 213         val &= ~GPIO_GPCTR0_IOTR_MASK;
 214         val |= GPIO_GPCTR0_IOTR_CMD_INPUT;
 215         writel(val, reg_base + GPIO_CONTROL(gpio));
 216
 217         raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 218
 219         return 0;
 220 }
 221
 222 static int bcm_kona_gpio_direction_output(struct gpio_chip *chip,
 223                                           unsigned gpio, int value)
 224 {
 225         struct bcm_kona_gpio *kona_gpio;
 226         void __iomem *reg_base;
 227         int bank_id = GPIO_BANK(gpio);
 228         int bit = GPIO_BIT(gpio);
 229         u32 val, reg_offset;
 230         unsigned long flags;
 231
 232         kona_gpio = gpiochip_get_data(chip);
 233         reg_base = kona_gpio->reg_base;
 234         raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 235
 236         val = readl(reg_base + GPIO_CONTROL(gpio));
 237         val &= ~GPIO_GPCTR0_IOTR_MASK;
 238         val |= GPIO_GPCTR0_IOTR_CMD_0UTPUT;
 239         writel(val, reg_base + GPIO_CONTROL(gpio));
 240         reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
 241
 242         val = readl(reg_base + reg_offset);
 243         val |= BIT(bit);
 244         writel(val, reg_base + reg_offset);
 245
 246         raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 247
 248         return 0;
 249 }
 250
 251 static int bcm_kona_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
 252 {
 253         struct bcm_kona_gpio *kona_gpio;
 254
 255         kona_gpio = gpiochip_get_data(chip);
 256         if (gpio >= kona_gpio->gpio_chip.ngpio)
 257                 return -ENXIO;
 258         return irq_create_mapping(kona_gpio->irq_domain, gpio);
 259 }
 260
 261 static int bcm_kona_gpio_set_debounce(struct gpio_chip *chip, unsigned gpio,
 262                                       unsigned debounce)
 263 {
 264         struct bcm_kona_gpio *kona_gpio;
 265         void __iomem *reg_base;
 266         u32 val, res;
 267         unsigned long flags;
 268
 269         kona_gpio = gpiochip_get_data(chip);
 270         reg_base = kona_gpio->reg_base;
 271         /* debounce must be 1-128ms (or 0) */
 272         if ((debounce > 0 && debounce < 1000) || debounce > 128000) {
 273                 dev_err(chip->parent, "Debounce value %u not in range\n",
 274                         debounce);
 275                 return -EINVAL;
 276         }
 277
 278         /* calculate debounce bit value */
 279         if (debounce != 0) {
 280                 /* Convert to ms */
 281                 debounce /= 1000;
 282                 /* find the MSB */
 283                 res = fls(debounce) - 1;
 284                 /* Check if MSB-1 is set (round up or down) */
 285                 if (res > 0 && (debounce & BIT(res - 1)))
 286                         res++;
 287         }
 288
 289         /* spin lock for read-modify-write of the GPIO register */
 290         raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 291
 292         val = readl(reg_base + GPIO_CONTROL(gpio));
 293         val &= ~GPIO_GPCTR0_DBR_MASK;
 294
 295         if (debounce == 0) {
 296                 /* disable debounce */
 297                 val &= ~GPIO_GPCTR0_DB_ENABLE_MASK;
 298         } else {
 299                 val |= GPIO_GPCTR0_DB_ENABLE_MASK |
 300                     (res << GPIO_GPCTR0_DBR_SHIFT);
 301         }
 302
 303         writel(val, reg_base + GPIO_CONTROL(gpio));
 304
 305         raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 306
 307         return 0;
 308 }
 309
 310 static int bcm_kona_gpio_set_config(struct gpio_chip *chip, unsigned gpio,
 311                                     unsigned long config)
 312 {
 313         u32 debounce;
 314
 315         if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
 316                 return -ENOTSUPP;
 317
 318         debounce = pinconf_to_config_argument(config);
 319         return bcm_kona_gpio_set_debounce(chip, gpio, debounce);
 320 }
 321
 322 static const struct gpio_chip template_chip = {
 323         .label = "bcm-kona-gpio",
 324         .owner = THIS_MODULE,
 325         .request = bcm_kona_gpio_request,
 326         .free = bcm_kona_gpio_free,
 327         .get_direction = bcm_kona_gpio_get_dir,
 328         .direction_input = bcm_kona_gpio_direction_input,
 329         .get = bcm_kona_gpio_get,
 330         .direction_output = bcm_kona_gpio_direction_output,
 331         .set = bcm_kona_gpio_set,
 332         .set_config = bcm_kona_gpio_set_config,
 333         .to_irq = bcm_kona_gpio_to_irq,
 334         .base = 0,
 335 };
 336
 337 static void bcm_kona_gpio_irq_ack(struct irq_data *d)
 338 {
 339         struct bcm_kona_gpio *kona_gpio;
 340         void __iomem *reg_base;
 341         unsigned gpio = d->hwirq;
 342         int bank_id = GPIO_BANK(gpio);
 343         int bit = GPIO_BIT(gpio);
 344         u32 val;
 345         unsigned long flags;
 346
 347         kona_gpio = irq_data_get_irq_chip_data(d);
 348         reg_base = kona_gpio->reg_base;
 349         raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 350
 351         val = readl(reg_base + GPIO_INT_STATUS(bank_id));
 352         val |= BIT(bit);
 353         writel(val, reg_base + GPIO_INT_STATUS(bank_id));
 354
 355         raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 356 }
 357
 358 static void bcm_kona_gpio_irq_mask(struct irq_data *d)
 359 {
 360         struct bcm_kona_gpio *kona_gpio;
 361         void __iomem *reg_base;
 362         unsigned gpio = d->hwirq;
 363         int bank_id = GPIO_BANK(gpio);
 364         int bit = GPIO_BIT(gpio);
 365         u32 val;
 366         unsigned long flags;
 367
 368         kona_gpio = irq_data_get_irq_chip_data(d);
 369         reg_base = kona_gpio->reg_base;
 370         raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 371
 372         val = readl(reg_base + GPIO_INT_MASK(bank_id));
 373         val |= BIT(bit);
 374         writel(val, reg_base + GPIO_INT_MASK(bank_id));
 375         gpiochip_disable_irq(&kona_gpio->gpio_chip, gpio);
 376
 377         raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 378 }
 379
 380 static void bcm_kona_gpio_irq_unmask(struct irq_data *d)
 381 {
 382         struct bcm_kona_gpio *kona_gpio;
 383         void __iomem *reg_base;
 384         unsigned gpio = d->hwirq;
 385         int bank_id = GPIO_BANK(gpio);
 386         int bit = GPIO_BIT(gpio);
 387         u32 val;
 388         unsigned long flags;
 389
 390         kona_gpio = irq_data_get_irq_chip_data(d);
 391         reg_base = kona_gpio->reg_base;
 392         raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 393
 394         val = readl(reg_base + GPIO_INT_MSKCLR(bank_id));
 395         val |= BIT(bit);
 396         writel(val, reg_base + GPIO_INT_MSKCLR(bank_id));
 397         gpiochip_enable_irq(&kona_gpio->gpio_chip, gpio);
 398
 399         raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 400 }
 401
 402 static int bcm_kona_gpio_irq_set_type(struct irq_data *d, unsigned int type)
 403 {
 404         struct bcm_kona_gpio *kona_gpio;
 405         void __iomem *reg_base;
 406         unsigned gpio = d->hwirq;
 407         u32 lvl_type;
 408         u32 val;
 409         unsigned long flags;
 410
 411         kona_gpio = irq_data_get_irq_chip_data(d);
 412         reg_base = kona_gpio->reg_base;
 413         switch (type & IRQ_TYPE_SENSE_MASK) {
 414         case IRQ_TYPE_EDGE_RISING:
 415                 lvl_type = GPIO_GPCTR0_ITR_CMD_RISING_EDGE;
 416                 break;
 417
 418         case IRQ_TYPE_EDGE_FALLING:
 419                 lvl_type = GPIO_GPCTR0_ITR_CMD_FALLING_EDGE;
 420                 break;
 421
 422         case IRQ_TYPE_EDGE_BOTH:
 423                 lvl_type = GPIO_GPCTR0_ITR_CMD_BOTH_EDGE;
 424                 break;
 425
 426         case IRQ_TYPE_LEVEL_HIGH:
 427         case IRQ_TYPE_LEVEL_LOW:
 428                 /* BCM GPIO doesn't support level triggering */
 429         default:
 430                 dev_err(kona_gpio->gpio_chip.parent,
 431                         "Invalid BCM GPIO irq type 0x%x\n", type);
 432                 return -EINVAL;
 433         }
 434
 435         raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 436
 437         val = readl(reg_base + GPIO_CONTROL(gpio));
 438         val &= ~GPIO_GPCTR0_ITR_MASK;
 439         val |= lvl_type << GPIO_GPCTR0_ITR_SHIFT;
 440         writel(val, reg_base + GPIO_CONTROL(gpio));
 441
 442         raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 443
 444         return 0;
 445 }
 446
 447 static void bcm_kona_gpio_irq_handler(struct irq_desc *desc)
 448 {
 449         void __iomem *reg_base;
 450         int bit, bank_id;
 451         unsigned long sta;
 452         struct bcm_kona_gpio_bank *bank = irq_desc_get_handler_data(desc);
 453         struct irq_chip *chip = irq_desc_get_chip(desc);
 454
 455         chained_irq_enter(chip, desc);
 456
 457         /*
 458          * For bank interrupts, we can't use chip_data to store the kona_gpio
 459          * pointer, since GIC needs it for its own purposes. Therefore, we get
 460          * our pointer from the bank structure.
 461          */
 462         reg_base = bank->kona_gpio->reg_base;
 463         bank_id = bank->id;
 464
 465         while ((sta = readl(reg_base + GPIO_INT_STATUS(bank_id)) &
 466                     (~(readl(reg_base + GPIO_INT_MASK(bank_id)))))) {
 467                 for_each_set_bit(bit, &sta, 32) {
 468                         int hwirq = GPIO_PER_BANK * bank_id + bit;
 469                         int child_irq =
 470                                 irq_find_mapping(bank->kona_gpio->irq_domain,
 471                                                  hwirq);
 472                         /*
 473                          * Clear interrupt before handler is called so we don't
 474                          * miss any interrupt occurred during executing them.
 475                          */
 476                         writel(readl(reg_base + GPIO_INT_STATUS(bank_id)) |
 477                                BIT(bit), reg_base + GPIO_INT_STATUS(bank_id));
 478                         /* Invoke interrupt handler */
 479                         generic_handle_irq(child_irq);
 480                 }
 481         }
 482
 483         chained_irq_exit(chip, desc);
 484 }
 485
 486 static int bcm_kona_gpio_irq_reqres(struct irq_data *d)
 487 {
 488         struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
 489
 490         return gpiochip_reqres_irq(&kona_gpio->gpio_chip, d->hwirq);
 491 }
 492
 493 static void bcm_kona_gpio_irq_relres(struct irq_data *d)
 494 {
 495         struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
 496
 497         gpiochip_relres_irq(&kona_gpio->gpio_chip, d->hwirq);
 498 }
 499
 500 static struct irq_chip bcm_gpio_irq_chip = {
 501         .name = "bcm-kona-gpio",
 502         .irq_ack = bcm_kona_gpio_irq_ack,
 503         .irq_mask = bcm_kona_gpio_irq_mask,
 504         .irq_unmask = bcm_kona_gpio_irq_unmask,
 505         .irq_set_type = bcm_kona_gpio_irq_set_type,
 506         .irq_request_resources = bcm_kona_gpio_irq_reqres,
 507         .irq_release_resources = bcm_kona_gpio_irq_relres,
 508 };
 509
 510 static struct of_device_id const bcm_kona_gpio_of_match[] = {
 511         { .compatible = "brcm,kona-gpio" },
 512         {}
 513 };
 514
 515 /*
 516  * This lock class tells lockdep that GPIO irqs are in a different
 517  * category than their parents, so it won't report false recursion.
 518  */
 519 static struct lock_class_key gpio_lock_class;
 520 static struct lock_class_key gpio_request_class;
 521
 522 static int bcm_kona_gpio_irq_map(struct irq_domain *d, unsigned int irq,
 523                                  irq_hw_number_t hwirq)
 524 {
 525         int ret;
 526
 527         ret = irq_set_chip_data(irq, d->host_data);
 528         if (ret < 0)
 529                 return ret;
 530         irq_set_lockdep_class(irq, &gpio_lock_class, &gpio_request_class);
 531         irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip, handle_simple_irq);
 532         irq_set_noprobe(irq);
 533
 534         return 0;
 535 }
 536
 537 static void bcm_kona_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
 538 {
 539         irq_set_chip_and_handler(irq, NULL, NULL);
 540         irq_set_chip_data(irq, NULL);
 541 }
 542
 543 static const struct irq_domain_ops bcm_kona_irq_ops = {
 544         .map = bcm_kona_gpio_irq_map,
 545         .unmap = bcm_kona_gpio_irq_unmap,
 546         .xlate = irq_domain_xlate_twocell,
 547 };
 548
 549 static void bcm_kona_gpio_reset(struct bcm_kona_gpio *kona_gpio)
 550 {
 551         void __iomem *reg_base;
 552         int i;
 553
 554         reg_base = kona_gpio->reg_base;
 555         /* disable interrupts and clear status */
 556         for (i = 0; i < kona_gpio->num_bank; i++) {
 557                 /* Unlock the entire bank first */
 558                 bcm_kona_gpio_write_lock_regs(reg_base, i, UNLOCK_CODE);
 559                 writel(0xffffffff, reg_base + GPIO_INT_MASK(i));
 560                 writel(0xffffffff, reg_base + GPIO_INT_STATUS(i));
 561                 /* Now re-lock the bank */
 562                 bcm_kona_gpio_write_lock_regs(reg_base, i, LOCK_CODE);
 563         }
 564 }
 565
 566 static int bcm_kona_gpio_probe(struct platform_device *pdev)
 567 {
 568         struct device *dev = &pdev->dev;
 569         const struct of_device_id *match;
 570         struct bcm_kona_gpio_bank *bank;
 571         struct bcm_kona_gpio *kona_gpio;
 572         struct gpio_chip *chip;
 573         int ret;
 574         int i;
 575
 576         match = of_match_device(bcm_kona_gpio_of_match, dev);
 577         if (!match) {
 578                 dev_err(dev, "Failed to find gpio controller\n");
 579                 return -ENODEV;
 580         }
 581
 582         kona_gpio = devm_kzalloc(dev, sizeof(*kona_gpio), GFP_KERNEL);
 583         if (!kona_gpio)
 584                 return -ENOMEM;
 585
 586         kona_gpio->gpio_chip = template_chip;
 587         chip = &kona_gpio->gpio_chip;
 588         ret = platform_irq_count(pdev);
 589         if (!ret) {
 590                 dev_err(dev, "Couldn't determine # GPIO banks\n");
 591                 return -ENOENT;
 592         } else if (ret < 0) {
 593                 if (ret != -EPROBE_DEFER)
 594                         dev_err(dev, "Couldn't determine GPIO banks: (%pe)\n",
 595                                 ERR_PTR(ret));
 596                 return ret;
 597         }
 598         kona_gpio->num_bank = ret;
 599
 600         if (kona_gpio->num_bank > GPIO_MAX_BANK_NUM) {
 601                 dev_err(dev, "Too many GPIO banks configured (max=%d)\n",
 602                         GPIO_MAX_BANK_NUM);
 603                 return -ENXIO;
 604         }
 605         kona_gpio->banks = devm_kcalloc(dev,
 606                                         kona_gpio->num_bank,
 607                                         sizeof(*kona_gpio->banks),
 608                                         GFP_KERNEL);
 609         if (!kona_gpio->banks)
 610                 return -ENOMEM;
 611
 612         kona_gpio->pdev = pdev;
 613         platform_set_drvdata(pdev, kona_gpio);
 614         chip->of_node = dev->of_node;
 615         chip->ngpio = kona_gpio->num_bank * GPIO_PER_BANK;
 616
 617         kona_gpio->irq_domain = irq_domain_add_linear(dev->of_node,
 618                                                       chip->ngpio,
 619                                                       &bcm_kona_irq_ops,
 620                                                       kona_gpio);
 621         if (!kona_gpio->irq_domain) {
 622                 dev_err(dev, "Couldn't allocate IRQ domain\n");
 623                 return -ENXIO;
 624         }
 625
 626         kona_gpio->reg_base = devm_platform_ioremap_resource(pdev, 0);
 627         if (IS_ERR(kona_gpio->reg_base)) {
 628                 ret = PTR_ERR(kona_gpio->reg_base);
 629                 goto err_irq_domain;
 630         }
 631
 632         for (i = 0; i < kona_gpio->num_bank; i++) {
 633                 bank = &kona_gpio->banks[i];
 634                 bank->id = i;
 635                 bank->irq = platform_get_irq(pdev, i);
 636                 bank->kona_gpio = kona_gpio;
 637                 if (bank->irq < 0) {
 638                         dev_err(dev, "Couldn't get IRQ for bank %d", i);
 639                         ret = -ENOENT;
 640                         goto err_irq_domain;
 641                 }
 642         }
 643
 644         dev_info(&pdev->dev, "Setting up Kona GPIO\n");
 645
 646         bcm_kona_gpio_reset(kona_gpio);
 647
 648         ret = devm_gpiochip_add_data(dev, chip, kona_gpio);
 649         if (ret < 0) {
 650                 dev_err(dev, "Couldn't add GPIO chip -- %d\n", ret);
 651                 goto err_irq_domain;
 652         }
 653         for (i = 0; i < kona_gpio->num_bank; i++) {
 654                 bank = &kona_gpio->banks[i];
 655                 irq_set_chained_handler_and_data(bank->irq,
 656                                                  bcm_kona_gpio_irq_handler,
 657                                                  bank);
 658         }
 659
 660         raw_spin_lock_init(&kona_gpio->lock);
 661
 662         return 0;
 663
 664 err_irq_domain:
 665         irq_domain_remove(kona_gpio->irq_domain);
 666
 667         return ret;
 668 }
 669
 670 static struct platform_driver bcm_kona_gpio_driver = {
 671         .driver = {
 672                         .name = "bcm-kona-gpio",
 673                         .of_match_table = bcm_kona_gpio_of_match,
 674         },
 675         .probe = bcm_kona_gpio_probe,
 676 };
 677 builtin_platform_driver(bcm_kona_gpio_driver);