linux/drivers/gpio/gpio-bcm-kona.c
<<
>>
Prefs
   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/of_irq.h>
  23#include <linux/init.h>
  24#include <linux/irqdomain.h>
  25#include <linux/irqchip/chained_irq.h>
  26
  27#define BCM_GPIO_PASSWD                         0x00a5a501
  28#define GPIO_PER_BANK                           32
  29#define GPIO_MAX_BANK_NUM                       8
  30
  31#define GPIO_BANK(gpio)                         ((gpio) >> 5)
  32#define GPIO_BIT(gpio)                          ((gpio) & (GPIO_PER_BANK - 1))
  33
  34/* There is a GPIO control register for each GPIO */
  35#define GPIO_CONTROL(gpio)                      (0x00000100 + ((gpio) << 2))
  36
  37/* The remaining registers are per GPIO bank */
  38#define GPIO_OUT_STATUS(bank)                   (0x00000000 + ((bank) << 2))
  39#define GPIO_IN_STATUS(bank)                    (0x00000020 + ((bank) << 2))
  40#define GPIO_OUT_SET(bank)                      (0x00000040 + ((bank) << 2))
  41#define GPIO_OUT_CLEAR(bank)                    (0x00000060 + ((bank) << 2))
  42#define GPIO_INT_STATUS(bank)                   (0x00000080 + ((bank) << 2))
  43#define GPIO_INT_MASK(bank)                     (0x000000a0 + ((bank) << 2))
  44#define GPIO_INT_MSKCLR(bank)                   (0x000000c0 + ((bank) << 2))
  45#define GPIO_PWD_STATUS(bank)                   (0x00000500 + ((bank) << 2))
  46
  47#define GPIO_GPPWR_OFFSET                       0x00000520
  48
  49#define GPIO_GPCTR0_DBR_SHIFT                   5
  50#define GPIO_GPCTR0_DBR_MASK                    0x000001e0
  51
  52#define GPIO_GPCTR0_ITR_SHIFT                   3
  53#define GPIO_GPCTR0_ITR_MASK                    0x00000018
  54#define GPIO_GPCTR0_ITR_CMD_RISING_EDGE         0x00000001
  55#define GPIO_GPCTR0_ITR_CMD_FALLING_EDGE        0x00000002
  56#define GPIO_GPCTR0_ITR_CMD_BOTH_EDGE           0x00000003
  57
  58#define GPIO_GPCTR0_IOTR_MASK                   0x00000001
  59#define GPIO_GPCTR0_IOTR_CMD_0UTPUT             0x00000000
  60#define GPIO_GPCTR0_IOTR_CMD_INPUT              0x00000001
  61
  62#define GPIO_GPCTR0_DB_ENABLE_MASK              0x00000100
  63
  64#define LOCK_CODE                               0xffffffff
  65#define UNLOCK_CODE                             0x00000000
  66
  67struct bcm_kona_gpio {
  68        void __iomem *reg_base;
  69        int num_bank;
  70        raw_spinlock_t lock;
  71        struct gpio_chip gpio_chip;
  72        struct irq_domain *irq_domain;
  73        struct bcm_kona_gpio_bank *banks;
  74        struct platform_device *pdev;
  75};
  76
  77struct bcm_kona_gpio_bank {
  78        int id;
  79        int irq;
  80        /* Used in the interrupt handler */
  81        struct bcm_kona_gpio *kona_gpio;
  82};
  83
  84static inline void bcm_kona_gpio_write_lock_regs(void __iomem *reg_base,
  85                                                int bank_id, u32 lockcode)
  86{
  87        writel(BCM_GPIO_PASSWD, reg_base + GPIO_GPPWR_OFFSET);
  88        writel(lockcode, reg_base + GPIO_PWD_STATUS(bank_id));
  89}
  90
  91static void bcm_kona_gpio_lock_gpio(struct bcm_kona_gpio *kona_gpio,
  92                                        unsigned gpio)
  93{
  94        u32 val;
  95        unsigned long flags;
  96        int bank_id = GPIO_BANK(gpio);
  97
  98        raw_spin_lock_irqsave(&kona_gpio->lock, flags);
  99
 100        val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
 101        val |= BIT(gpio);
 102        bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
 103
 104        raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 105}
 106
 107static void bcm_kona_gpio_unlock_gpio(struct bcm_kona_gpio *kona_gpio,
 108                                        unsigned gpio)
 109{
 110        u32 val;
 111        unsigned long flags;
 112        int bank_id = GPIO_BANK(gpio);
 113
 114        raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 115
 116        val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
 117        val &= ~BIT(gpio);
 118        bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
 119
 120        raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 121}
 122
 123static int bcm_kona_gpio_get_dir(struct gpio_chip *chip, unsigned gpio)
 124{
 125        struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
 126        void __iomem *reg_base = kona_gpio->reg_base;
 127        u32 val;
 128
 129        val = readl(reg_base + GPIO_CONTROL(gpio)) & GPIO_GPCTR0_IOTR_MASK;
 130        return !!val;
 131}
 132
 133static void bcm_kona_gpio_set(struct gpio_chip *chip, unsigned gpio, int value)
 134{
 135        struct bcm_kona_gpio *kona_gpio;
 136        void __iomem *reg_base;
 137        int bank_id = GPIO_BANK(gpio);
 138        int bit = GPIO_BIT(gpio);
 139        u32 val, reg_offset;
 140        unsigned long flags;
 141
 142        kona_gpio = gpiochip_get_data(chip);
 143        reg_base = kona_gpio->reg_base;
 144        raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 145
 146        /* this function only applies to output pin */
 147        if (bcm_kona_gpio_get_dir(chip, gpio) == 1)
 148                goto out;
 149
 150        reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
 151
 152        val = readl(reg_base + reg_offset);
 153        val |= BIT(bit);
 154        writel(val, reg_base + reg_offset);
 155
 156out:
 157        raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 158}
 159
 160static int bcm_kona_gpio_get(struct gpio_chip *chip, unsigned gpio)
 161{
 162        struct bcm_kona_gpio *kona_gpio;
 163        void __iomem *reg_base;
 164        int bank_id = GPIO_BANK(gpio);
 165        int bit = GPIO_BIT(gpio);
 166        u32 val, reg_offset;
 167        unsigned long flags;
 168
 169        kona_gpio = gpiochip_get_data(chip);
 170        reg_base = kona_gpio->reg_base;
 171        raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 172
 173        if (bcm_kona_gpio_get_dir(chip, gpio) == 1)
 174                reg_offset = GPIO_IN_STATUS(bank_id);
 175        else
 176                reg_offset = GPIO_OUT_STATUS(bank_id);
 177
 178        /* read the GPIO bank status */
 179        val = readl(reg_base + reg_offset);
 180
 181        raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 182
 183        /* return the specified bit status */
 184        return !!(val & BIT(bit));
 185}
 186
 187static int bcm_kona_gpio_request(struct gpio_chip *chip, unsigned gpio)
 188{
 189        struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
 190
 191        bcm_kona_gpio_unlock_gpio(kona_gpio, gpio);
 192        return 0;
 193}
 194
 195static void bcm_kona_gpio_free(struct gpio_chip *chip, unsigned gpio)
 196{
 197        struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
 198
 199        bcm_kona_gpio_lock_gpio(kona_gpio, gpio);
 200}
 201
 202static int bcm_kona_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
 203{
 204        struct bcm_kona_gpio *kona_gpio;
 205        void __iomem *reg_base;
 206        u32 val;
 207        unsigned long flags;
 208
 209        kona_gpio = gpiochip_get_data(chip);
 210        reg_base = kona_gpio->reg_base;
 211        raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 212
 213        val = readl(reg_base + GPIO_CONTROL(gpio));
 214        val &= ~GPIO_GPCTR0_IOTR_MASK;
 215        val |= GPIO_GPCTR0_IOTR_CMD_INPUT;
 216        writel(val, reg_base + GPIO_CONTROL(gpio));
 217
 218        raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 219
 220        return 0;
 221}
 222
 223static int bcm_kona_gpio_direction_output(struct gpio_chip *chip,
 224                                          unsigned gpio, int value)
 225{
 226        struct bcm_kona_gpio *kona_gpio;
 227        void __iomem *reg_base;
 228        int bank_id = GPIO_BANK(gpio);
 229        int bit = GPIO_BIT(gpio);
 230        u32 val, reg_offset;
 231        unsigned long flags;
 232
 233        kona_gpio = gpiochip_get_data(chip);
 234        reg_base = kona_gpio->reg_base;
 235        raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 236
 237        val = readl(reg_base + GPIO_CONTROL(gpio));
 238        val &= ~GPIO_GPCTR0_IOTR_MASK;
 239        val |= GPIO_GPCTR0_IOTR_CMD_0UTPUT;
 240        writel(val, reg_base + GPIO_CONTROL(gpio));
 241        reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
 242
 243        val = readl(reg_base + reg_offset);
 244        val |= BIT(bit);
 245        writel(val, reg_base + reg_offset);
 246
 247        raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 248
 249        return 0;
 250}
 251
 252static int bcm_kona_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
 253{
 254        struct bcm_kona_gpio *kona_gpio;
 255
 256        kona_gpio = gpiochip_get_data(chip);
 257        if (gpio >= kona_gpio->gpio_chip.ngpio)
 258                return -ENXIO;
 259        return irq_create_mapping(kona_gpio->irq_domain, gpio);
 260}
 261
 262static int bcm_kona_gpio_set_debounce(struct gpio_chip *chip, unsigned gpio,
 263                                      unsigned debounce)
 264{
 265        struct bcm_kona_gpio *kona_gpio;
 266        void __iomem *reg_base;
 267        u32 val, res;
 268        unsigned long flags;
 269
 270        kona_gpio = gpiochip_get_data(chip);
 271        reg_base = kona_gpio->reg_base;
 272        /* debounce must be 1-128ms (or 0) */
 273        if ((debounce > 0 && debounce < 1000) || debounce > 128000) {
 274                dev_err(chip->parent, "Debounce value %u not in range\n",
 275                        debounce);
 276                return -EINVAL;
 277        }
 278
 279        /* calculate debounce bit value */
 280        if (debounce != 0) {
 281                /* Convert to ms */
 282                debounce /= 1000;
 283                /* find the MSB */
 284                res = fls(debounce) - 1;
 285                /* Check if MSB-1 is set (round up or down) */
 286                if (res > 0 && (debounce & BIT(res - 1)))
 287                        res++;
 288        }
 289
 290        /* spin lock for read-modify-write of the GPIO register */
 291        raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 292
 293        val = readl(reg_base + GPIO_CONTROL(gpio));
 294        val &= ~GPIO_GPCTR0_DBR_MASK;
 295
 296        if (debounce == 0) {
 297                /* disable debounce */
 298                val &= ~GPIO_GPCTR0_DB_ENABLE_MASK;
 299        } else {
 300                val |= GPIO_GPCTR0_DB_ENABLE_MASK |
 301                    (res << GPIO_GPCTR0_DBR_SHIFT);
 302        }
 303
 304        writel(val, reg_base + GPIO_CONTROL(gpio));
 305
 306        raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 307
 308        return 0;
 309}
 310
 311static int bcm_kona_gpio_set_config(struct gpio_chip *chip, unsigned gpio,
 312                                    unsigned long config)
 313{
 314        u32 debounce;
 315
 316        if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
 317                return -ENOTSUPP;
 318
 319        debounce = pinconf_to_config_argument(config);
 320        return bcm_kona_gpio_set_debounce(chip, gpio, debounce);
 321}
 322
 323static const struct gpio_chip template_chip = {
 324        .label = "bcm-kona-gpio",
 325        .owner = THIS_MODULE,
 326        .request = bcm_kona_gpio_request,
 327        .free = bcm_kona_gpio_free,
 328        .get_direction = bcm_kona_gpio_get_dir,
 329        .direction_input = bcm_kona_gpio_direction_input,
 330        .get = bcm_kona_gpio_get,
 331        .direction_output = bcm_kona_gpio_direction_output,
 332        .set = bcm_kona_gpio_set,
 333        .set_config = bcm_kona_gpio_set_config,
 334        .to_irq = bcm_kona_gpio_to_irq,
 335        .base = 0,
 336};
 337
 338static void bcm_kona_gpio_irq_ack(struct irq_data *d)
 339{
 340        struct bcm_kona_gpio *kona_gpio;
 341        void __iomem *reg_base;
 342        unsigned gpio = d->hwirq;
 343        int bank_id = GPIO_BANK(gpio);
 344        int bit = GPIO_BIT(gpio);
 345        u32 val;
 346        unsigned long flags;
 347
 348        kona_gpio = irq_data_get_irq_chip_data(d);
 349        reg_base = kona_gpio->reg_base;
 350        raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 351
 352        val = readl(reg_base + GPIO_INT_STATUS(bank_id));
 353        val |= BIT(bit);
 354        writel(val, reg_base + GPIO_INT_STATUS(bank_id));
 355
 356        raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 357}
 358
 359static void bcm_kona_gpio_irq_mask(struct irq_data *d)
 360{
 361        struct bcm_kona_gpio *kona_gpio;
 362        void __iomem *reg_base;
 363        unsigned gpio = d->hwirq;
 364        int bank_id = GPIO_BANK(gpio);
 365        int bit = GPIO_BIT(gpio);
 366        u32 val;
 367        unsigned long flags;
 368
 369        kona_gpio = irq_data_get_irq_chip_data(d);
 370        reg_base = kona_gpio->reg_base;
 371        raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 372
 373        val = readl(reg_base + GPIO_INT_MASK(bank_id));
 374        val |= BIT(bit);
 375        writel(val, reg_base + GPIO_INT_MASK(bank_id));
 376
 377        raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 378}
 379
 380static 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
 398        raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 399}
 400
 401static int bcm_kona_gpio_irq_set_type(struct irq_data *d, unsigned int type)
 402{
 403        struct bcm_kona_gpio *kona_gpio;
 404        void __iomem *reg_base;
 405        unsigned gpio = d->hwirq;
 406        u32 lvl_type;
 407        u32 val;
 408        unsigned long flags;
 409
 410        kona_gpio = irq_data_get_irq_chip_data(d);
 411        reg_base = kona_gpio->reg_base;
 412        switch (type & IRQ_TYPE_SENSE_MASK) {
 413        case IRQ_TYPE_EDGE_RISING:
 414                lvl_type = GPIO_GPCTR0_ITR_CMD_RISING_EDGE;
 415                break;
 416
 417        case IRQ_TYPE_EDGE_FALLING:
 418                lvl_type = GPIO_GPCTR0_ITR_CMD_FALLING_EDGE;
 419                break;
 420
 421        case IRQ_TYPE_EDGE_BOTH:
 422                lvl_type = GPIO_GPCTR0_ITR_CMD_BOTH_EDGE;
 423                break;
 424
 425        case IRQ_TYPE_LEVEL_HIGH:
 426        case IRQ_TYPE_LEVEL_LOW:
 427                /* BCM GPIO doesn't support level triggering */
 428        default:
 429                dev_err(kona_gpio->gpio_chip.parent,
 430                        "Invalid BCM GPIO irq type 0x%x\n", type);
 431                return -EINVAL;
 432        }
 433
 434        raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 435
 436        val = readl(reg_base + GPIO_CONTROL(gpio));
 437        val &= ~GPIO_GPCTR0_ITR_MASK;
 438        val |= lvl_type << GPIO_GPCTR0_ITR_SHIFT;
 439        writel(val, reg_base + GPIO_CONTROL(gpio));
 440
 441        raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
 442
 443        return 0;
 444}
 445
 446static void bcm_kona_gpio_irq_handler(struct irq_desc *desc)
 447{
 448        void __iomem *reg_base;
 449        int bit, bank_id;
 450        unsigned long sta;
 451        struct bcm_kona_gpio_bank *bank = irq_desc_get_handler_data(desc);
 452        struct irq_chip *chip = irq_desc_get_chip(desc);
 453
 454        chained_irq_enter(chip, desc);
 455
 456        /*
 457         * For bank interrupts, we can't use chip_data to store the kona_gpio
 458         * pointer, since GIC needs it for its own purposes. Therefore, we get
 459         * our pointer from the bank structure.
 460         */
 461        reg_base = bank->kona_gpio->reg_base;
 462        bank_id = bank->id;
 463
 464        while ((sta = readl(reg_base + GPIO_INT_STATUS(bank_id)) &
 465                    (~(readl(reg_base + GPIO_INT_MASK(bank_id)))))) {
 466                for_each_set_bit(bit, &sta, 32) {
 467                        int hwirq = GPIO_PER_BANK * bank_id + bit;
 468                        int child_irq =
 469                                irq_find_mapping(bank->kona_gpio->irq_domain,
 470                                                 hwirq);
 471                        /*
 472                         * Clear interrupt before handler is called so we don't
 473                         * miss any interrupt occurred during executing them.
 474                         */
 475                        writel(readl(reg_base + GPIO_INT_STATUS(bank_id)) |
 476                               BIT(bit), reg_base + GPIO_INT_STATUS(bank_id));
 477                        /* Invoke interrupt handler */
 478                        generic_handle_irq(child_irq);
 479                }
 480        }
 481
 482        chained_irq_exit(chip, desc);
 483}
 484
 485static int bcm_kona_gpio_irq_reqres(struct irq_data *d)
 486{
 487        struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
 488        int ret;
 489
 490        ret = gpiochip_lock_as_irq(&kona_gpio->gpio_chip, d->hwirq);
 491        if (ret) {
 492                dev_err(kona_gpio->gpio_chip.parent,
 493                        "unable to lock HW IRQ %lu for IRQ\n",
 494                        d->hwirq);
 495                return ret;
 496        }
 497        return 0;
 498}
 499
 500static void bcm_kona_gpio_irq_relres(struct irq_data *d)
 501{
 502        struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
 503
 504        gpiochip_unlock_as_irq(&kona_gpio->gpio_chip, d->hwirq);
 505}
 506
 507static struct irq_chip bcm_gpio_irq_chip = {
 508        .name = "bcm-kona-gpio",
 509        .irq_ack = bcm_kona_gpio_irq_ack,
 510        .irq_mask = bcm_kona_gpio_irq_mask,
 511        .irq_unmask = bcm_kona_gpio_irq_unmask,
 512        .irq_set_type = bcm_kona_gpio_irq_set_type,
 513        .irq_request_resources = bcm_kona_gpio_irq_reqres,
 514        .irq_release_resources = bcm_kona_gpio_irq_relres,
 515};
 516
 517static struct of_device_id const bcm_kona_gpio_of_match[] = {
 518        { .compatible = "brcm,kona-gpio" },
 519        {}
 520};
 521
 522/*
 523 * This lock class tells lockdep that GPIO irqs are in a different
 524 * category than their parents, so it won't report false recursion.
 525 */
 526static struct lock_class_key gpio_lock_class;
 527static struct lock_class_key gpio_request_class;
 528
 529static int bcm_kona_gpio_irq_map(struct irq_domain *d, unsigned int irq,
 530                                 irq_hw_number_t hwirq)
 531{
 532        int ret;
 533
 534        ret = irq_set_chip_data(irq, d->host_data);
 535        if (ret < 0)
 536                return ret;
 537        irq_set_lockdep_class(irq, &gpio_lock_class, &gpio_request_class);
 538        irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip, handle_simple_irq);
 539        irq_set_noprobe(irq);
 540
 541        return 0;
 542}
 543
 544static void bcm_kona_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
 545{
 546        irq_set_chip_and_handler(irq, NULL, NULL);
 547        irq_set_chip_data(irq, NULL);
 548}
 549
 550static const struct irq_domain_ops bcm_kona_irq_ops = {
 551        .map = bcm_kona_gpio_irq_map,
 552        .unmap = bcm_kona_gpio_irq_unmap,
 553        .xlate = irq_domain_xlate_twocell,
 554};
 555
 556static void bcm_kona_gpio_reset(struct bcm_kona_gpio *kona_gpio)
 557{
 558        void __iomem *reg_base;
 559        int i;
 560
 561        reg_base = kona_gpio->reg_base;
 562        /* disable interrupts and clear status */
 563        for (i = 0; i < kona_gpio->num_bank; i++) {
 564                /* Unlock the entire bank first */
 565                bcm_kona_gpio_write_lock_regs(reg_base, i, UNLOCK_CODE);
 566                writel(0xffffffff, reg_base + GPIO_INT_MASK(i));
 567                writel(0xffffffff, reg_base + GPIO_INT_STATUS(i));
 568                /* Now re-lock the bank */
 569                bcm_kona_gpio_write_lock_regs(reg_base, i, LOCK_CODE);
 570        }
 571}
 572
 573static int bcm_kona_gpio_probe(struct platform_device *pdev)
 574{
 575        struct device *dev = &pdev->dev;
 576        const struct of_device_id *match;
 577        struct resource *res;
 578        struct bcm_kona_gpio_bank *bank;
 579        struct bcm_kona_gpio *kona_gpio;
 580        struct gpio_chip *chip;
 581        int ret;
 582        int i;
 583
 584        match = of_match_device(bcm_kona_gpio_of_match, dev);
 585        if (!match) {
 586                dev_err(dev, "Failed to find gpio controller\n");
 587                return -ENODEV;
 588        }
 589
 590        kona_gpio = devm_kzalloc(dev, sizeof(*kona_gpio), GFP_KERNEL);
 591        if (!kona_gpio)
 592                return -ENOMEM;
 593
 594        kona_gpio->gpio_chip = template_chip;
 595        chip = &kona_gpio->gpio_chip;
 596        kona_gpio->num_bank = of_irq_count(dev->of_node);
 597        if (kona_gpio->num_bank == 0) {
 598                dev_err(dev, "Couldn't determine # GPIO banks\n");
 599                return -ENOENT;
 600        }
 601        if (kona_gpio->num_bank > GPIO_MAX_BANK_NUM) {
 602                dev_err(dev, "Too many GPIO banks configured (max=%d)\n",
 603                        GPIO_MAX_BANK_NUM);
 604                return -ENXIO;
 605        }
 606        kona_gpio->banks = devm_kcalloc(dev,
 607                                        kona_gpio->num_bank,
 608                                        sizeof(*kona_gpio->banks),
 609                                        GFP_KERNEL);
 610        if (!kona_gpio->banks)
 611                return -ENOMEM;
 612
 613        kona_gpio->pdev = pdev;
 614        platform_set_drvdata(pdev, kona_gpio);
 615        chip->of_node = dev->of_node;
 616        chip->ngpio = kona_gpio->num_bank * GPIO_PER_BANK;
 617
 618        kona_gpio->irq_domain = irq_domain_add_linear(dev->of_node,
 619                                                      chip->ngpio,
 620                                                      &bcm_kona_irq_ops,
 621                                                      kona_gpio);
 622        if (!kona_gpio->irq_domain) {
 623                dev_err(dev, "Couldn't allocate IRQ domain\n");
 624                return -ENXIO;
 625        }
 626
 627        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 628        kona_gpio->reg_base = devm_ioremap_resource(dev, res);
 629        if (IS_ERR(kona_gpio->reg_base)) {
 630                ret = -ENXIO;
 631                goto err_irq_domain;
 632        }
 633
 634        for (i = 0; i < kona_gpio->num_bank; i++) {
 635                bank = &kona_gpio->banks[i];
 636                bank->id = i;
 637                bank->irq = platform_get_irq(pdev, i);
 638                bank->kona_gpio = kona_gpio;
 639                if (bank->irq < 0) {
 640                        dev_err(dev, "Couldn't get IRQ for bank %d", i);
 641                        ret = -ENOENT;
 642                        goto err_irq_domain;
 643                }
 644        }
 645
 646        dev_info(&pdev->dev, "Setting up Kona GPIO\n");
 647
 648        bcm_kona_gpio_reset(kona_gpio);
 649
 650        ret = devm_gpiochip_add_data(dev, chip, kona_gpio);
 651        if (ret < 0) {
 652                dev_err(dev, "Couldn't add GPIO chip -- %d\n", ret);
 653                goto err_irq_domain;
 654        }
 655        for (i = 0; i < kona_gpio->num_bank; i++) {
 656                bank = &kona_gpio->banks[i];
 657                irq_set_chained_handler_and_data(bank->irq,
 658                                                 bcm_kona_gpio_irq_handler,
 659                                                 bank);
 660        }
 661
 662        raw_spin_lock_init(&kona_gpio->lock);
 663
 664        return 0;
 665
 666err_irq_domain:
 667        irq_domain_remove(kona_gpio->irq_domain);
 668
 669        return ret;
 670}
 671
 672static struct platform_driver bcm_kona_gpio_driver = {
 673        .driver = {
 674                        .name = "bcm-kona-gpio",
 675                        .of_match_table = bcm_kona_gpio_of_match,
 676        },
 677        .probe = bcm_kona_gpio_probe,
 678};
 679builtin_platform_driver(bcm_kona_gpio_driver);
 680