// SPDX-License-Identifier: GPL-2.0-only
/*
 * Broadcom Kona GPIO Driver
 *
 * Author: Broadcom Corporation <bcm-kernel-feedback-list@broadcom.com>
 * Copyright (C) 2012-2014 Broadcom Corporation
 */

#include <linux/bitops.h>
#include <linux/cleanup.h>
#include <linux/err.h>
#include <linux/gpio/driver.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/irqdomain.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/mod_devicetable.h>
#include <linux/platform_device.h>
#include <linux/property.h>

#define BCM_GPIO_PASSWD                         0x00a5a501
#define GPIO_PER_BANK                           32
#define GPIO_MAX_BANK_NUM                       8

#define GPIO_BANK(gpio)                         ((gpio) >> 5)
#define GPIO_BIT(gpio)                          ((gpio) & (GPIO_PER_BANK - 1))

/* There is a GPIO control register for each GPIO */
#define GPIO_CONTROL(gpio)                      (0x00000100 + ((gpio) << 2))

/* The remaining registers are per GPIO bank */
#define GPIO_OUT_STATUS(bank)                   (0x00000000 + ((bank) << 2))
#define GPIO_IN_STATUS(bank)                    (0x00000020 + ((bank) << 2))
#define GPIO_OUT_SET(bank)                      (0x00000040 + ((bank) << 2))
#define GPIO_OUT_CLEAR(bank)                    (0x00000060 + ((bank) << 2))
#define GPIO_INT_STATUS(bank)                   (0x00000080 + ((bank) << 2))
#define GPIO_INT_MASK(bank)                     (0x000000a0 + ((bank) << 2))
#define GPIO_INT_MSKCLR(bank)                   (0x000000c0 + ((bank) << 2))
#define GPIO_PWD_STATUS(bank)                   (0x00000500 + ((bank) << 2))

#define GPIO_GPPWR_OFFSET                       0x00000520

#define GPIO_GPCTR0_DBR_SHIFT                   5
#define GPIO_GPCTR0_DBR_MASK                    0x000001e0

#define GPIO_GPCTR0_ITR_SHIFT                   3
#define GPIO_GPCTR0_ITR_MASK                    0x00000018
#define GPIO_GPCTR0_ITR_CMD_RISING_EDGE         0x00000001
#define GPIO_GPCTR0_ITR_CMD_FALLING_EDGE        0x00000002
#define GPIO_GPCTR0_ITR_CMD_BOTH_EDGE           0x00000003

#define GPIO_GPCTR0_IOTR_MASK                   0x00000001
#define GPIO_GPCTR0_IOTR_CMD_0UTPUT             0x00000000
#define GPIO_GPCTR0_IOTR_CMD_INPUT              0x00000001

#define GPIO_GPCTR0_DB_ENABLE_MASK              0x00000100

#define LOCK_CODE                               0xffffffff
#define UNLOCK_CODE                             0x00000000

struct bcm_kona_gpio {
        void __iomem *reg_base;
        int num_bank;
        raw_spinlock_t lock;
        struct gpio_chip gpio_chip;
        struct irq_domain *irq_domain;
        struct bcm_kona_gpio_bank *banks;
};

struct bcm_kona_gpio_bank {
        int id;
        int irq;
        /*
         * Used to keep track of lock/unlock operations for each GPIO in the
         * bank.
         *
         * All GPIOs are locked by default (see bcm_kona_gpio_reset), and the
         * unlock count for all GPIOs is 0 by default. Each unlock increments
         * the counter, and each lock decrements the counter.
         *
         * The lock function only locks the GPIO once its unlock counter is
         * down to 0. This is necessary because the GPIO is unlocked in two
         * places in this driver: once for requested GPIOs, and once for
         * requested IRQs. Since it is possible for a GPIO to be requested
         * as both a GPIO and an IRQ, we need to ensure that we don't lock it
         * too early.
         */
        u8 gpio_unlock_count[GPIO_PER_BANK];
        /* Used in the interrupt handler */
        struct bcm_kona_gpio *kona_gpio;
};

static inline void bcm_kona_gpio_write_lock_regs(void __iomem *reg_base,
                                                int bank_id, u32 lockcode)
{
        writel(BCM_GPIO_PASSWD, reg_base + GPIO_GPPWR_OFFSET);
        writel(lockcode, reg_base + GPIO_PWD_STATUS(bank_id));
}

static void bcm_kona_gpio_lock_gpio(struct bcm_kona_gpio *kona_gpio,
                                        unsigned gpio)
{
        u32 val;
        int bank_id = GPIO_BANK(gpio);
        int bit = GPIO_BIT(gpio);
        struct bcm_kona_gpio_bank *bank = &kona_gpio->banks[bank_id];

        if (bank->gpio_unlock_count[bit] == 0) {
                dev_err(kona_gpio->gpio_chip.parent,
                        "Unbalanced locks for GPIO %u\n", gpio);
                return;
        }

        if (--bank->gpio_unlock_count[bit] == 0) {
                guard(raw_spinlock_irqsave)(&kona_gpio->lock);

                val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
                val |= BIT(bit);
                bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
        }
}

static void bcm_kona_gpio_unlock_gpio(struct bcm_kona_gpio *kona_gpio,
                                        unsigned gpio)
{
        u32 val;
        int bank_id = GPIO_BANK(gpio);
        int bit = GPIO_BIT(gpio);
        struct bcm_kona_gpio_bank *bank = &kona_gpio->banks[bank_id];

        if (bank->gpio_unlock_count[bit] == 0) {
                guard(raw_spinlock_irqsave)(&kona_gpio->lock);

                val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
                val &= ~BIT(bit);
                bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
        }

        ++bank->gpio_unlock_count[bit];
}

static int bcm_kona_gpio_get_dir(struct gpio_chip *chip, unsigned gpio)
{
        struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
        void __iomem *reg_base = kona_gpio->reg_base;
        u32 val;

        val = readl(reg_base + GPIO_CONTROL(gpio)) & GPIO_GPCTR0_IOTR_MASK;
        return val ? GPIO_LINE_DIRECTION_IN : GPIO_LINE_DIRECTION_OUT;
}

static int bcm_kona_gpio_set(struct gpio_chip *chip, unsigned int gpio,
                             int value)
{
        struct bcm_kona_gpio *kona_gpio;
        void __iomem *reg_base;
        int bank_id = GPIO_BANK(gpio);
        int bit = GPIO_BIT(gpio);
        u32 val, reg_offset;

        kona_gpio = gpiochip_get_data(chip);
        reg_base = kona_gpio->reg_base;

        guard(raw_spinlock_irqsave)(&kona_gpio->lock);

        /* this function only applies to output pin */
        if (bcm_kona_gpio_get_dir(chip, gpio) == GPIO_LINE_DIRECTION_IN)
                return 0;

        reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);

        val = readl(reg_base + reg_offset);
        val |= BIT(bit);
        writel(val, reg_base + reg_offset);

        return 0;
}

static int bcm_kona_gpio_get(struct gpio_chip *chip, unsigned gpio)
{
        struct bcm_kona_gpio *kona_gpio;
        void __iomem *reg_base;
        int bank_id = GPIO_BANK(gpio);
        int bit = GPIO_BIT(gpio);
        u32 val, reg_offset;

        kona_gpio = gpiochip_get_data(chip);
        reg_base = kona_gpio->reg_base;

        guard(raw_spinlock_irqsave)(&kona_gpio->lock);

        if (bcm_kona_gpio_get_dir(chip, gpio) == GPIO_LINE_DIRECTION_IN)
                reg_offset = GPIO_IN_STATUS(bank_id);
        else
                reg_offset = GPIO_OUT_STATUS(bank_id);

        /* read the GPIO bank status */
        val = readl(reg_base + reg_offset);

        /* return the specified bit status */
        return !!(val & BIT(bit));
}

static int bcm_kona_gpio_request(struct gpio_chip *chip, unsigned gpio)
{
        struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);

        bcm_kona_gpio_unlock_gpio(kona_gpio, gpio);
        return 0;
}

static void bcm_kona_gpio_free(struct gpio_chip *chip, unsigned gpio)
{
        struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);

        bcm_kona_gpio_lock_gpio(kona_gpio, gpio);
}

static int bcm_kona_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
{
        struct bcm_kona_gpio *kona_gpio;
        void __iomem *reg_base;
        u32 val;

        kona_gpio = gpiochip_get_data(chip);
        reg_base = kona_gpio->reg_base;

        guard(raw_spinlock_irqsave)(&kona_gpio->lock);

        val = readl(reg_base + GPIO_CONTROL(gpio));
        val &= ~GPIO_GPCTR0_IOTR_MASK;
        val |= GPIO_GPCTR0_IOTR_CMD_INPUT;
        writel(val, reg_base + GPIO_CONTROL(gpio));

        return 0;
}

static int bcm_kona_gpio_direction_output(struct gpio_chip *chip,
                                          unsigned gpio, int value)
{
        struct bcm_kona_gpio *kona_gpio;
        void __iomem *reg_base;
        int bank_id = GPIO_BANK(gpio);
        int bit = GPIO_BIT(gpio);
        u32 val, reg_offset;

        kona_gpio = gpiochip_get_data(chip);
        reg_base = kona_gpio->reg_base;

        guard(raw_spinlock_irqsave)(&kona_gpio->lock);

        val = readl(reg_base + GPIO_CONTROL(gpio));
        val &= ~GPIO_GPCTR0_IOTR_MASK;
        val |= GPIO_GPCTR0_IOTR_CMD_0UTPUT;
        writel(val, reg_base + GPIO_CONTROL(gpio));
        reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);

        val = readl(reg_base + reg_offset);
        val |= BIT(bit);
        writel(val, reg_base + reg_offset);

        return 0;
}

static int bcm_kona_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
{
        struct bcm_kona_gpio *kona_gpio;

        kona_gpio = gpiochip_get_data(chip);
        if (gpio >= kona_gpio->gpio_chip.ngpio)
                return -ENXIO;
        return irq_create_mapping(kona_gpio->irq_domain, gpio);
}

static int bcm_kona_gpio_set_debounce(struct gpio_chip *chip, unsigned gpio,
                                      unsigned debounce)
{
        struct bcm_kona_gpio *kona_gpio;
        void __iomem *reg_base;
        u32 val, res;

        kona_gpio = gpiochip_get_data(chip);
        reg_base = kona_gpio->reg_base;
        /* debounce must be 1-128ms (or 0) */
        if ((debounce > 0 && debounce < 1000) || debounce > 128000) {
                dev_err(chip->parent, "Debounce value %u not in range\n",
                        debounce);
                return -EINVAL;
        }

        /* calculate debounce bit value */
        if (debounce != 0) {
                /* Convert to ms */
                debounce /= 1000;
                /* find the MSB */
                res = fls(debounce) - 1;
                /* Check if MSB-1 is set (round up or down) */
                if (res > 0 && (debounce & BIT(res - 1)))
                        res++;
        }

        /* spin lock for read-modify-write of the GPIO register */
        guard(raw_spinlock_irqsave)(&kona_gpio->lock);

        val = readl(reg_base + GPIO_CONTROL(gpio));
        val &= ~GPIO_GPCTR0_DBR_MASK;

        if (debounce == 0) {
                /* disable debounce */
                val &= ~GPIO_GPCTR0_DB_ENABLE_MASK;
        } else {
                val |= GPIO_GPCTR0_DB_ENABLE_MASK |
                    (res << GPIO_GPCTR0_DBR_SHIFT);
        }

        writel(val, reg_base + GPIO_CONTROL(gpio));

        return 0;
}

static int bcm_kona_gpio_set_config(struct gpio_chip *chip, unsigned gpio,
                                    unsigned long config)
{
        u32 debounce;

        if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
                return -ENOTSUPP;

        debounce = pinconf_to_config_argument(config);
        return bcm_kona_gpio_set_debounce(chip, gpio, debounce);
}

static const struct gpio_chip template_chip = {
        .label = "bcm-kona-gpio",
        .owner = THIS_MODULE,
        .request = bcm_kona_gpio_request,
        .free = bcm_kona_gpio_free,
        .get_direction = bcm_kona_gpio_get_dir,
        .direction_input = bcm_kona_gpio_direction_input,
        .get = bcm_kona_gpio_get,
        .direction_output = bcm_kona_gpio_direction_output,
        .set = bcm_kona_gpio_set,
        .set_config = bcm_kona_gpio_set_config,
        .to_irq = bcm_kona_gpio_to_irq,
        .base = 0,
};

static void bcm_kona_gpio_irq_ack(struct irq_data *d)
{
        struct bcm_kona_gpio *kona_gpio;
        void __iomem *reg_base;
        unsigned gpio = d->hwirq;
        int bank_id = GPIO_BANK(gpio);
        int bit = GPIO_BIT(gpio);
        u32 val;

        kona_gpio = irq_data_get_irq_chip_data(d);
        reg_base = kona_gpio->reg_base;

        guard(raw_spinlock_irqsave)(&kona_gpio->lock);

        val = readl(reg_base + GPIO_INT_STATUS(bank_id));
        val |= BIT(bit);
        writel(val, reg_base + GPIO_INT_STATUS(bank_id));
}

static void bcm_kona_gpio_irq_mask(struct irq_data *d)
{
        struct bcm_kona_gpio *kona_gpio;
        void __iomem *reg_base;
        unsigned gpio = d->hwirq;
        int bank_id = GPIO_BANK(gpio);
        int bit = GPIO_BIT(gpio);
        u32 val;

        kona_gpio = irq_data_get_irq_chip_data(d);
        reg_base = kona_gpio->reg_base;

        guard(raw_spinlock_irqsave)(&kona_gpio->lock);

        val = readl(reg_base + GPIO_INT_MASK(bank_id));
        val |= BIT(bit);
        writel(val, reg_base + GPIO_INT_MASK(bank_id));
        gpiochip_disable_irq(&kona_gpio->gpio_chip, gpio);
}

static void bcm_kona_gpio_irq_unmask(struct irq_data *d)
{
        struct bcm_kona_gpio *kona_gpio;
        void __iomem *reg_base;
        unsigned gpio = d->hwirq;
        int bank_id = GPIO_BANK(gpio);
        int bit = GPIO_BIT(gpio);
        u32 val;

        kona_gpio = irq_data_get_irq_chip_data(d);
        reg_base = kona_gpio->reg_base;

        guard(raw_spinlock_irqsave)(&kona_gpio->lock);

        val = readl(reg_base + GPIO_INT_MSKCLR(bank_id));
        val |= BIT(bit);
        writel(val, reg_base + GPIO_INT_MSKCLR(bank_id));
        gpiochip_enable_irq(&kona_gpio->gpio_chip, gpio);
}

static int bcm_kona_gpio_irq_set_type(struct irq_data *d, unsigned int type)
{
        struct bcm_kona_gpio *kona_gpio;
        void __iomem *reg_base;
        unsigned gpio = d->hwirq;
        u32 lvl_type;
        u32 val;

        kona_gpio = irq_data_get_irq_chip_data(d);
        reg_base = kona_gpio->reg_base;
        switch (type & IRQ_TYPE_SENSE_MASK) {
        case IRQ_TYPE_EDGE_RISING:
                lvl_type = GPIO_GPCTR0_ITR_CMD_RISING_EDGE;
                break;

        case IRQ_TYPE_EDGE_FALLING:
                lvl_type = GPIO_GPCTR0_ITR_CMD_FALLING_EDGE;
                break;

        case IRQ_TYPE_EDGE_BOTH:
                lvl_type = GPIO_GPCTR0_ITR_CMD_BOTH_EDGE;
                break;

        case IRQ_TYPE_LEVEL_HIGH:
        case IRQ_TYPE_LEVEL_LOW:
                /* BCM GPIO doesn't support level triggering */
        default:
                dev_err(kona_gpio->gpio_chip.parent,
                        "Invalid BCM GPIO irq type 0x%x\n", type);
                return -EINVAL;
        }

        guard(raw_spinlock_irqsave)(&kona_gpio->lock);

        val = readl(reg_base + GPIO_CONTROL(gpio));
        val &= ~GPIO_GPCTR0_ITR_MASK;
        val |= lvl_type << GPIO_GPCTR0_ITR_SHIFT;
        writel(val, reg_base + GPIO_CONTROL(gpio));

        return 0;
}

static void bcm_kona_gpio_irq_handler(struct irq_desc *desc)
{
        void __iomem *reg_base;
        int bit, bank_id;
        unsigned long sta;
        struct bcm_kona_gpio_bank *bank = irq_desc_get_handler_data(desc);
        struct irq_chip *chip = irq_desc_get_chip(desc);

        chained_irq_enter(chip, desc);

        /*
         * For bank interrupts, we can't use chip_data to store the kona_gpio
         * pointer, since GIC needs it for its own purposes. Therefore, we get
         * our pointer from the bank structure.
         */
        reg_base = bank->kona_gpio->reg_base;
        bank_id = bank->id;

        while ((sta = readl(reg_base + GPIO_INT_STATUS(bank_id)) &
                    (~(readl(reg_base + GPIO_INT_MASK(bank_id)))))) {
                for_each_set_bit(bit, &sta, 32) {
                        int hwirq = GPIO_PER_BANK * bank_id + bit;
                        /*
                         * Clear interrupt before handler is called so we don't
                         * miss any interrupt occurred during executing them.
                         */
                        writel(readl(reg_base + GPIO_INT_STATUS(bank_id)) |
                               BIT(bit), reg_base + GPIO_INT_STATUS(bank_id));
                        /* Invoke interrupt handler */
                        generic_handle_domain_irq(bank->kona_gpio->irq_domain,
                                                  hwirq);
                }
        }

        chained_irq_exit(chip, desc);
}

static int bcm_kona_gpio_irq_reqres(struct irq_data *d)
{
        struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
        unsigned int gpio = d->hwirq;

        /*
         * We need to unlock the GPIO before any other operations are performed
         * on the relevant GPIO configuration registers
         */
        bcm_kona_gpio_unlock_gpio(kona_gpio, gpio);

        return gpiochip_reqres_irq(&kona_gpio->gpio_chip, gpio);
}

static void bcm_kona_gpio_irq_relres(struct irq_data *d)
{
        struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
        unsigned int gpio = d->hwirq;

        /* Once we no longer use it, lock the GPIO again */
        bcm_kona_gpio_lock_gpio(kona_gpio, gpio);

        gpiochip_relres_irq(&kona_gpio->gpio_chip, gpio);
}

static struct irq_chip bcm_gpio_irq_chip = {
        .name = "bcm-kona-gpio",
        .irq_ack = bcm_kona_gpio_irq_ack,
        .irq_mask = bcm_kona_gpio_irq_mask,
        .irq_unmask = bcm_kona_gpio_irq_unmask,
        .irq_set_type = bcm_kona_gpio_irq_set_type,
        .irq_request_resources = bcm_kona_gpio_irq_reqres,
        .irq_release_resources = bcm_kona_gpio_irq_relres,
        .flags = IRQCHIP_IMMUTABLE,
};

static struct of_device_id const bcm_kona_gpio_of_match[] = {
        { .compatible = "brcm,kona-gpio" },
        {}
};

/*
 * This lock class tells lockdep that GPIO irqs are in a different
 * category than their parents, so it won't report false recursion.
 */
static struct lock_class_key gpio_lock_class;
static struct lock_class_key gpio_request_class;

static int bcm_kona_gpio_irq_map(struct irq_domain *d, unsigned int irq,
                                 irq_hw_number_t hwirq)
{
        int ret;

        ret = irq_set_chip_data(irq, d->host_data);
        if (ret < 0)
                return ret;
        irq_set_lockdep_class(irq, &gpio_lock_class, &gpio_request_class);
        irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip, handle_simple_irq);
        irq_set_noprobe(irq);

        return 0;
}

static void bcm_kona_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
{
        irq_set_chip_and_handler(irq, NULL, NULL);
        irq_set_chip_data(irq, NULL);
}

static const struct irq_domain_ops bcm_kona_irq_ops = {
        .map = bcm_kona_gpio_irq_map,
        .unmap = bcm_kona_gpio_irq_unmap,
        .xlate = irq_domain_xlate_twocell,
};

static void bcm_kona_gpio_reset(struct bcm_kona_gpio *kona_gpio)
{
        void __iomem *reg_base;
        int i;

        reg_base = kona_gpio->reg_base;
        /* disable interrupts and clear status */
        for (i = 0; i < kona_gpio->num_bank; i++) {
                /* Unlock the entire bank first */
                bcm_kona_gpio_write_lock_regs(reg_base, i, UNLOCK_CODE);
                writel(0xffffffff, reg_base + GPIO_INT_MASK(i));
                writel(0xffffffff, reg_base + GPIO_INT_STATUS(i));
                /* Now re-lock the bank */
                bcm_kona_gpio_write_lock_regs(reg_base, i, LOCK_CODE);
        }
}

static int bcm_kona_gpio_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct bcm_kona_gpio_bank *bank;
        struct bcm_kona_gpio *kona_gpio;
        struct gpio_chip *chip;
        int ret;
        int i;

        kona_gpio = devm_kzalloc(dev, sizeof(*kona_gpio), GFP_KERNEL);
        if (!kona_gpio)
                return -ENOMEM;

        kona_gpio->gpio_chip = template_chip;
        chip = &kona_gpio->gpio_chip;
        ret = platform_irq_count(pdev);
        if (!ret) {
                dev_err(dev, "Couldn't determine # GPIO banks\n");
                return -ENOENT;
        } else if (ret < 0) {
                return dev_err_probe(dev, ret, "Couldn't determine GPIO banks\n");
        }
        kona_gpio->num_bank = ret;

        if (kona_gpio->num_bank > GPIO_MAX_BANK_NUM) {
                dev_err(dev, "Too many GPIO banks configured (max=%d)\n",
                        GPIO_MAX_BANK_NUM);
                return -ENXIO;
        }
        kona_gpio->banks = devm_kcalloc(dev,
                                        kona_gpio->num_bank,
                                        sizeof(*kona_gpio->banks),
                                        GFP_KERNEL);
        if (!kona_gpio->banks)
                return -ENOMEM;

        chip->parent = dev;
        chip->ngpio = kona_gpio->num_bank * GPIO_PER_BANK;

        kona_gpio->irq_domain = irq_domain_create_linear(dev_fwnode(dev),
                                                         chip->ngpio,
                                                         &bcm_kona_irq_ops,
                                                         kona_gpio);
        if (!kona_gpio->irq_domain) {
                dev_err(dev, "Couldn't allocate IRQ domain\n");
                return -ENXIO;
        }

        kona_gpio->reg_base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(kona_gpio->reg_base)) {
                ret = PTR_ERR(kona_gpio->reg_base);
                goto err_irq_domain;
        }

        for (i = 0; i < kona_gpio->num_bank; i++) {
                bank = &kona_gpio->banks[i];
                bank->id = i;
                bank->irq = platform_get_irq(pdev, i);
                bank->kona_gpio = kona_gpio;
                if (bank->irq < 0) {
                        dev_err(dev, "Couldn't get IRQ for bank %d\n", i);
                        ret = -ENOENT;
                        goto err_irq_domain;
                }
        }

        dev_info(&pdev->dev, "Setting up Kona GPIO\n");

        bcm_kona_gpio_reset(kona_gpio);

        ret = devm_gpiochip_add_data(dev, chip, kona_gpio);
        if (ret < 0) {
                dev_err(dev, "Couldn't add GPIO chip -- %d\n", ret);
                goto err_irq_domain;
        }
        for (i = 0; i < kona_gpio->num_bank; i++) {
                bank = &kona_gpio->banks[i];
                irq_set_chained_handler_and_data(bank->irq,
                                                 bcm_kona_gpio_irq_handler,
                                                 bank);
        }

        raw_spin_lock_init(&kona_gpio->lock);

        return 0;

err_irq_domain:
        irq_domain_remove(kona_gpio->irq_domain);

        return ret;
}

static struct platform_driver bcm_kona_gpio_driver = {
        .driver = {
                        .name = "bcm-kona-gpio",
                        .of_match_table = bcm_kona_gpio_of_match,
        },
        .probe = bcm_kona_gpio_probe,
};
builtin_platform_driver(bcm_kona_gpio_driver);