/*
 * Support functions for OMAP GPIO
 *
 * Copyright (C) 2003-2005 Nokia Corporation
 * Written by Juha Yrjölä <juha.yrjola@nokia.com>
 *
 * Copyright (C) 2009 Texas Instruments
 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/syscore_ops.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/device.h>
#include <linux/pm_runtime.h>
#include <linux/pm.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/irqdomain.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/gpio.h>
#include <linux/platform_data/gpio-omap.h>

#define OFF_MODE        1

static LIST_HEAD(omap_gpio_list);

struct gpio_regs {
        u32 irqenable1;
        u32 irqenable2;
        u32 wake_en;
        u32 ctrl;
        u32 oe;
        u32 leveldetect0;
        u32 leveldetect1;
        u32 risingdetect;
        u32 fallingdetect;
        u32 dataout;
        u32 debounce;
        u32 debounce_en;
};

struct gpio_bank {
        struct list_head node;
        void __iomem *base;
        u16 irq;
        struct irq_domain *domain;
        u32 non_wakeup_gpios;
        u32 enabled_non_wakeup_gpios;
        struct gpio_regs context;
        u32 saved_datain;
        u32 level_mask;
        u32 toggle_mask;
        spinlock_t lock;
        struct gpio_chip chip;
        struct clk *dbck;
        u32 mod_usage;
        u32 irq_usage;
        u32 dbck_enable_mask;
        bool dbck_enabled;
        struct device *dev;
        bool is_mpuio;
        bool dbck_flag;
        bool loses_context;
        bool context_valid;
        int stride;
        u32 width;
        int context_loss_count;
        int power_mode;
        bool workaround_enabled;

        void (*set_dataout)(struct gpio_bank *bank, int gpio, int enable);
        int (*get_context_loss_count)(struct device *dev);

        struct omap_gpio_reg_offs *regs;
};

#define GPIO_INDEX(bank, gpio) (gpio % bank->width)
#define GPIO_BIT(bank, gpio) (1 << GPIO_INDEX(bank, gpio))
#define GPIO_MOD_CTRL_BIT       BIT(0)

#define BANK_USED(bank) (bank->mod_usage || bank->irq_usage)
#define LINE_USED(line, offset) (line & (1 << offset))

static int irq_to_gpio(struct gpio_bank *bank, unsigned int gpio_irq)
{
        return bank->chip.base + gpio_irq;
}

static int omap_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
        struct gpio_bank *bank = container_of(chip, struct gpio_bank, chip);

        return irq_find_mapping(bank->domain, offset);
}

static void _set_gpio_direction(struct gpio_bank *bank, int gpio, int is_input)
{
        void __iomem *reg = bank->base;
        u32 l;

        reg += bank->regs->direction;
        l = __raw_readl(reg);
        if (is_input)
                l |= 1 << gpio;
        else
                l &= ~(1 << gpio);
        __raw_writel(l, reg);
        bank->context.oe = l;
}


/* set data out value using dedicate set/clear register */
static void _set_gpio_dataout_reg(struct gpio_bank *bank, int gpio, int enable)
{
        void __iomem *reg = bank->base;
        u32 l = GPIO_BIT(bank, gpio);

        if (enable) {
                reg += bank->regs->set_dataout;
                bank->context.dataout |= l;
        } else {
                reg += bank->regs->clr_dataout;
                bank->context.dataout &= ~l;
        }

        __raw_writel(l, reg);
}

/* set data out value using mask register */
static void _set_gpio_dataout_mask(struct gpio_bank *bank, int gpio, int enable)
{
        void __iomem *reg = bank->base + bank->regs->dataout;
        u32 gpio_bit = GPIO_BIT(bank, gpio);
        u32 l;

        l = __raw_readl(reg);
        if (enable)
                l |= gpio_bit;
        else
                l &= ~gpio_bit;
        __raw_writel(l, reg);
        bank->context.dataout = l;
}

static int _get_gpio_datain(struct gpio_bank *bank, int offset)
{
        void __iomem *reg = bank->base + bank->regs->datain;

        return (__raw_readl(reg) & (1 << offset)) != 0;
}

static int _get_gpio_dataout(struct gpio_bank *bank, int offset)
{
        void __iomem *reg = bank->base + bank->regs->dataout;

        return (__raw_readl(reg) & (1 << offset)) != 0;
}

static inline void _gpio_rmw(void __iomem *base, u32 reg, u32 mask, bool set)
{
        int l = __raw_readl(base + reg);

        if (set)
                l |= mask;
        else
                l &= ~mask;

        __raw_writel(l, base + reg);
}

static inline void _gpio_dbck_enable(struct gpio_bank *bank)
{
        if (bank->dbck_enable_mask && !bank->dbck_enabled) {
                clk_enable(bank->dbck);
                bank->dbck_enabled = true;

                __raw_writel(bank->dbck_enable_mask,
                             bank->base + bank->regs->debounce_en);
        }
}

static inline void _gpio_dbck_disable(struct gpio_bank *bank)
{
        if (bank->dbck_enable_mask && bank->dbck_enabled) {
                /*
                 * Disable debounce before cutting it's clock. If debounce is
                 * enabled but the clock is not, GPIO module seems to be unable
                 * to detect events and generate interrupts at least on OMAP3.
                 */
                __raw_writel(0, bank->base + bank->regs->debounce_en);

                clk_disable(bank->dbck);
                bank->dbck_enabled = false;
        }
}

/**
 * _set_gpio_debounce - low level gpio debounce time
 * @bank: the gpio bank we're acting upon
 * @gpio: the gpio number on this @gpio
 * @debounce: debounce time to use
 *
 * OMAP's debounce time is in 31us steps so we need
 * to convert and round up to the closest unit.
 */
static void _set_gpio_debounce(struct gpio_bank *bank, unsigned gpio,
                unsigned debounce)
{
        void __iomem            *reg;
        u32                     val;
        u32                     l;

        if (!bank->dbck_flag)
                return;

        if (debounce < 32)
                debounce = 0x01;
        else if (debounce > 7936)
                debounce = 0xff;
        else
                debounce = (debounce / 0x1f) - 1;

        l = GPIO_BIT(bank, gpio);

        clk_enable(bank->dbck);
        reg = bank->base + bank->regs->debounce;
        __raw_writel(debounce, reg);

        reg = bank->base + bank->regs->debounce_en;
        val = __raw_readl(reg);

        if (debounce)
                val |= l;
        else
                val &= ~l;
        bank->dbck_enable_mask = val;

        __raw_writel(val, reg);
        clk_disable(bank->dbck);
        /*
         * Enable debounce clock per module.
         * This call is mandatory because in omap_gpio_request() when
         * *_runtime_get_sync() is called,  _gpio_dbck_enable() within
         * runtime callbck fails to turn on dbck because dbck_enable_mask
         * used within _gpio_dbck_enable() is still not initialized at
         * that point. Therefore we have to enable dbck here.
         */
        _gpio_dbck_enable(bank);
        if (bank->dbck_enable_mask) {
                bank->context.debounce = debounce;
                bank->context.debounce_en = val;
        }
}

/**
 * _clear_gpio_debounce - clear debounce settings for a gpio
 * @bank: the gpio bank we're acting upon
 * @gpio: the gpio number on this @gpio
 *
 * If a gpio is using debounce, then clear the debounce enable bit and if
 * this is the only gpio in this bank using debounce, then clear the debounce
 * time too. The debounce clock will also be disabled when calling this function
 * if this is the only gpio in the bank using debounce.
 */
static void _clear_gpio_debounce(struct gpio_bank *bank, unsigned gpio)
{
        u32 gpio_bit = GPIO_BIT(bank, gpio);

        if (!bank->dbck_flag)
                return;

        if (!(bank->dbck_enable_mask & gpio_bit))
                return;

        bank->dbck_enable_mask &= ~gpio_bit;
        bank->context.debounce_en &= ~gpio_bit;
        __raw_writel(bank->context.debounce_en,
                     bank->base + bank->regs->debounce_en);

        if (!bank->dbck_enable_mask) {
                bank->context.debounce = 0;
                __raw_writel(bank->context.debounce, bank->base +
                             bank->regs->debounce);
                clk_disable(bank->dbck);
                bank->dbck_enabled = false;
        }
}

static inline void set_gpio_trigger(struct gpio_bank *bank, int gpio,
                                                unsigned trigger)
{
        void __iomem *base = bank->base;
        u32 gpio_bit = 1 << gpio;

        _gpio_rmw(base, bank->regs->leveldetect0, gpio_bit,
                  trigger & IRQ_TYPE_LEVEL_LOW);
        _gpio_rmw(base, bank->regs->leveldetect1, gpio_bit,
                  trigger & IRQ_TYPE_LEVEL_HIGH);
        _gpio_rmw(base, bank->regs->risingdetect, gpio_bit,
                  trigger & IRQ_TYPE_EDGE_RISING);
        _gpio_rmw(base, bank->regs->fallingdetect, gpio_bit,
                  trigger & IRQ_TYPE_EDGE_FALLING);

        bank->context.leveldetect0 =
                        __raw_readl(bank->base + bank->regs->leveldetect0);
        bank->context.leveldetect1 =
                        __raw_readl(bank->base + bank->regs->leveldetect1);
        bank->context.risingdetect =
                        __raw_readl(bank->base + bank->regs->risingdetect);
        bank->context.fallingdetect =
                        __raw_readl(bank->base + bank->regs->fallingdetect);

        if (likely(!(bank->non_wakeup_gpios & gpio_bit))) {
                _gpio_rmw(base, bank->regs->wkup_en, gpio_bit, trigger != 0);
                bank->context.wake_en =
                        __raw_readl(bank->base + bank->regs->wkup_en);
        }

        /* This part needs to be executed always for OMAP{34xx, 44xx} */
        if (!bank->regs->irqctrl) {
                /* On omap24xx proceed only when valid GPIO bit is set */
                if (bank->non_wakeup_gpios) {
                        if (!(bank->non_wakeup_gpios & gpio_bit))
                                goto exit;
                }

                /*
                 * Log the edge gpio and manually trigger the IRQ
                 * after resume if the input level changes
                 * to avoid irq lost during PER RET/OFF mode
                 * Applies for omap2 non-wakeup gpio and all omap3 gpios
                 */
                if (trigger & IRQ_TYPE_EDGE_BOTH)
                        bank->enabled_non_wakeup_gpios |= gpio_bit;
                else
                        bank->enabled_non_wakeup_gpios &= ~gpio_bit;
        }

exit:
        bank->level_mask =
                __raw_readl(bank->base + bank->regs->leveldetect0) |
                __raw_readl(bank->base + bank->regs->leveldetect1);
}

#ifdef CONFIG_ARCH_OMAP1
/*
 * This only applies to chips that can't do both rising and falling edge
 * detection at once.  For all other chips, this function is a noop.
 */
static void _toggle_gpio_edge_triggering(struct gpio_bank *bank, int gpio)
{
        void __iomem *reg = bank->base;
        u32 l = 0;

        if (!bank->regs->irqctrl)
                return;

        reg += bank->regs->irqctrl;

        l = __raw_readl(reg);
        if ((l >> gpio) & 1)
                l &= ~(1 << gpio);
        else
                l |= 1 << gpio;

        __raw_writel(l, reg);
}
#else
static void _toggle_gpio_edge_triggering(struct gpio_bank *bank, int gpio) {}
#endif

static int _set_gpio_triggering(struct gpio_bank *bank, int gpio,
                                                        unsigned trigger)
{
        void __iomem *reg = bank->base;
        void __iomem *base = bank->base;
        u32 l = 0;

        if (bank->regs->leveldetect0 && bank->regs->wkup_en) {
                set_gpio_trigger(bank, gpio, trigger);
        } else if (bank->regs->irqctrl) {
                reg += bank->regs->irqctrl;

                l = __raw_readl(reg);
                if ((trigger & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH)
                        bank->toggle_mask |= 1 << gpio;
                if (trigger & IRQ_TYPE_EDGE_RISING)
                        l |= 1 << gpio;
                else if (trigger & IRQ_TYPE_EDGE_FALLING)
                        l &= ~(1 << gpio);
                else
                        return -EINVAL;

                __raw_writel(l, reg);
        } else if (bank->regs->edgectrl1) {
                if (gpio & 0x08)
                        reg += bank->regs->edgectrl2;
                else
                        reg += bank->regs->edgectrl1;

                gpio &= 0x07;
                l = __raw_readl(reg);
                l &= ~(3 << (gpio << 1));
                if (trigger & IRQ_TYPE_EDGE_RISING)
                        l |= 2 << (gpio << 1);
                if (trigger & IRQ_TYPE_EDGE_FALLING)
                        l |= 1 << (gpio << 1);

                /* Enable wake-up during idle for dynamic tick */
                _gpio_rmw(base, bank->regs->wkup_en, 1 << gpio, trigger);
                bank->context.wake_en =
                        __raw_readl(bank->base + bank->regs->wkup_en);
                __raw_writel(l, reg);
        }
        return 0;
}

static void _enable_gpio_module(struct gpio_bank *bank, unsigned offset)
{
        if (bank->regs->pinctrl) {
                void __iomem *reg = bank->base + bank->regs->pinctrl;

                /* Claim the pin for MPU */
                __raw_writel(__raw_readl(reg) | (1 << offset), reg);
        }

        if (bank->regs->ctrl && !BANK_USED(bank)) {
                void __iomem *reg = bank->base + bank->regs->ctrl;
                u32 ctrl;

                ctrl = __raw_readl(reg);
                /* Module is enabled, clocks are not gated */
                ctrl &= ~GPIO_MOD_CTRL_BIT;
                __raw_writel(ctrl, reg);
                bank->context.ctrl = ctrl;
        }
}

static void _disable_gpio_module(struct gpio_bank *bank, unsigned offset)
{
        void __iomem *base = bank->base;

        if (bank->regs->wkup_en &&
            !LINE_USED(bank->mod_usage, offset) &&
            !LINE_USED(bank->irq_usage, offset)) {
                /* Disable wake-up during idle for dynamic tick */
                _gpio_rmw(base, bank->regs->wkup_en, 1 << offset, 0);
                bank->context.wake_en =
                        __raw_readl(bank->base + bank->regs->wkup_en);
        }

        if (bank->regs->ctrl && !BANK_USED(bank)) {
                void __iomem *reg = bank->base + bank->regs->ctrl;
                u32 ctrl;

                ctrl = __raw_readl(reg);
                /* Module is disabled, clocks are gated */
                ctrl |= GPIO_MOD_CTRL_BIT;
                __raw_writel(ctrl, reg);
                bank->context.ctrl = ctrl;
        }
}

static int gpio_is_input(struct gpio_bank *bank, int mask)
{
        void __iomem *reg = bank->base + bank->regs->direction;

        return __raw_readl(reg) & mask;
}

static int gpio_irq_type(struct irq_data *d, unsigned type)
{
        struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
        unsigned gpio = 0;
        int retval;
        unsigned long flags;
        unsigned offset;

        if (!BANK_USED(bank))
                pm_runtime_get_sync(bank->dev);

#ifdef CONFIG_ARCH_OMAP1
        if (d->irq > IH_MPUIO_BASE)
                gpio = OMAP_MPUIO(d->irq - IH_MPUIO_BASE);
#endif

        if (!gpio)
                gpio = irq_to_gpio(bank, d->hwirq);

        if (type & ~IRQ_TYPE_SENSE_MASK)
                return -EINVAL;

        if (!bank->regs->leveldetect0 &&
                (type & (IRQ_TYPE_LEVEL_LOW|IRQ_TYPE_LEVEL_HIGH)))
                return -EINVAL;

        spin_lock_irqsave(&bank->lock, flags);
        offset = GPIO_INDEX(bank, gpio);
        retval = _set_gpio_triggering(bank, offset, type);
        if (!LINE_USED(bank->mod_usage, offset)) {
                _enable_gpio_module(bank, offset);
                _set_gpio_direction(bank, offset, 1);
        } else if (!gpio_is_input(bank, 1 << offset)) {
                spin_unlock_irqrestore(&bank->lock, flags);
                return -EINVAL;
        }

        bank->irq_usage |= 1 << GPIO_INDEX(bank, gpio);
        spin_unlock_irqrestore(&bank->lock, flags);

        if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
                __irq_set_handler_locked(d->irq, handle_level_irq);
        else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
                __irq_set_handler_locked(d->irq, handle_edge_irq);

        return retval;
}

static void _clear_gpio_irqbank(struct gpio_bank *bank, int gpio_mask)
{
        void __iomem *reg = bank->base;

        reg += bank->regs->irqstatus;
        __raw_writel(gpio_mask, reg);

        /* Workaround for clearing DSP GPIO interrupts to allow retention */
        if (bank->regs->irqstatus2) {
                reg = bank->base + bank->regs->irqstatus2;
                __raw_writel(gpio_mask, reg);
        }

        /* Flush posted write for the irq status to avoid spurious interrupts */
        __raw_readl(reg);
}

static inline void _clear_gpio_irqstatus(struct gpio_bank *bank, int gpio)
{
        _clear_gpio_irqbank(bank, GPIO_BIT(bank, gpio));
}

static u32 _get_gpio_irqbank_mask(struct gpio_bank *bank)
{
        void __iomem *reg = bank->base;
        u32 l;
        u32 mask = (1 << bank->width) - 1;

        reg += bank->regs->irqenable;
        l = __raw_readl(reg);
        if (bank->regs->irqenable_inv)
                l = ~l;
        l &= mask;
        return l;
}

static void _enable_gpio_irqbank(struct gpio_bank *bank, int gpio_mask)
{
        void __iomem *reg = bank->base;
        u32 l;

        if (bank->regs->set_irqenable) {
                reg += bank->regs->set_irqenable;
                l = gpio_mask;
                bank->context.irqenable1 |= gpio_mask;
        } else {
                reg += bank->regs->irqenable;
                l = __raw_readl(reg);
                if (bank->regs->irqenable_inv)
                        l &= ~gpio_mask;
                else
                        l |= gpio_mask;
                bank->context.irqenable1 = l;
        }

        __raw_writel(l, reg);
}

static void _disable_gpio_irqbank(struct gpio_bank *bank, int gpio_mask)
{
        void __iomem *reg = bank->base;
        u32 l;

        if (bank->regs->clr_irqenable) {
                reg += bank->regs->clr_irqenable;
                l = gpio_mask;
                bank->context.irqenable1 &= ~gpio_mask;
        } else {
                reg += bank->regs->irqenable;
                l = __raw_readl(reg);
                if (bank->regs->irqenable_inv)
                        l |= gpio_mask;
                else
                        l &= ~gpio_mask;
                bank->context.irqenable1 = l;
        }

        __raw_writel(l, reg);
}

static inline void _set_gpio_irqenable(struct gpio_bank *bank, int gpio, int enable)
{
        if (enable)
                _enable_gpio_irqbank(bank, GPIO_BIT(bank, gpio));
        else
                _disable_gpio_irqbank(bank, GPIO_BIT(bank, gpio));
}

/*
 * Note that ENAWAKEUP needs to be enabled in GPIO_SYSCONFIG register.
 * 1510 does not seem to have a wake-up register. If JTAG is connected
 * to the target, system will wake up always on GPIO events. While
 * system is running all registered GPIO interrupts need to have wake-up
 * enabled. When system is suspended, only selected GPIO interrupts need
 * to have wake-up enabled.
 */
static int _set_gpio_wakeup(struct gpio_bank *bank, int gpio, int enable)
{
        u32 gpio_bit = GPIO_BIT(bank, gpio);
        unsigned long flags;

        if (bank->non_wakeup_gpios & gpio_bit) {
                dev_err(bank->dev,
                        "Unable to modify wakeup on non-wakeup GPIO%d\n", gpio);
                return -EINVAL;
        }

        spin_lock_irqsave(&bank->lock, flags);
        if (enable)
                bank->context.wake_en |= gpio_bit;
        else
                bank->context.wake_en &= ~gpio_bit;

        __raw_writel(bank->context.wake_en, bank->base + bank->regs->wkup_en);
        spin_unlock_irqrestore(&bank->lock, flags);

        return 0;
}

static void _reset_gpio(struct gpio_bank *bank, int gpio)
{
        _set_gpio_direction(bank, GPIO_INDEX(bank, gpio), 1);
        _set_gpio_irqenable(bank, gpio, 0);
        _clear_gpio_irqstatus(bank, gpio);
        _set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), IRQ_TYPE_NONE);
        _clear_gpio_debounce(bank, gpio);
}

/* Use disable_irq_wake() and enable_irq_wake() functions from drivers */
static int gpio_wake_enable(struct irq_data *d, unsigned int enable)
{
        struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
        unsigned int gpio = irq_to_gpio(bank, d->hwirq);

        return _set_gpio_wakeup(bank, gpio, enable);
}

static int omap_gpio_request(struct gpio_chip *chip, unsigned offset)
{
        struct gpio_bank *bank = container_of(chip, struct gpio_bank, chip);
        unsigned long flags;

        /*
         * If this is the first gpio_request for the bank,
         * enable the bank module.
         */
        if (!BANK_USED(bank))
                pm_runtime_get_sync(bank->dev);

        spin_lock_irqsave(&bank->lock, flags);
        /* Set trigger to none. You need to enable the desired trigger with
         * request_irq() or set_irq_type(). Only do this if the IRQ line has
         * not already been requested.
         */
        if (!LINE_USED(bank->irq_usage, offset)) {
                _set_gpio_triggering(bank, offset, IRQ_TYPE_NONE);
                _enable_gpio_module(bank, offset);
        }
        bank->mod_usage |= 1 << offset;
        spin_unlock_irqrestore(&bank->lock, flags);

        return 0;
}

static void omap_gpio_free(struct gpio_chip *chip, unsigned offset)
{
        struct gpio_bank *bank = container_of(chip, struct gpio_bank, chip);
        unsigned long flags;

        spin_lock_irqsave(&bank->lock, flags);
        bank->mod_usage &= ~(1 << offset);
        _disable_gpio_module(bank, offset);
        _reset_gpio(bank, bank->chip.base + offset);
        spin_unlock_irqrestore(&bank->lock, flags);

        /*
         * If this is the last gpio to be freed in the bank,
         * disable the bank module.
         */
        if (!BANK_USED(bank))
                pm_runtime_put(bank->dev);
}

/*
 * We need to unmask the GPIO bank interrupt as soon as possible to
 * avoid missing GPIO interrupts for other lines in the bank.
 * Then we need to mask-read-clear-unmask the triggered GPIO lines
 * in the bank to avoid missing nested interrupts for a GPIO line.
 * If we wait to unmask individual GPIO lines in the bank after the
 * line's interrupt handler has been run, we may miss some nested
 * interrupts.
 */
static void gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
{
        void __iomem *isr_reg = NULL;
        u32 isr;
        unsigned int bit;
        struct gpio_bank *bank;
        int unmasked = 0;
        struct irq_chip *chip = irq_desc_get_chip(desc);

        chained_irq_enter(chip, desc);

        bank = irq_get_handler_data(irq);
        isr_reg = bank->base + bank->regs->irqstatus;
        pm_runtime_get_sync(bank->dev);

        if (WARN_ON(!isr_reg))
                goto exit;

        while (1) {
                u32 isr_saved, level_mask = 0;
                u32 enabled;

                enabled = _get_gpio_irqbank_mask(bank);
                isr_saved = isr = __raw_readl(isr_reg) & enabled;

                if (bank->level_mask)
                        level_mask = bank->level_mask & enabled;

                /* clear edge sensitive interrupts before handler(s) are
                called so that we don't miss any interrupt occurred while
                executing them */
                _disable_gpio_irqbank(bank, isr_saved & ~level_mask);
                _clear_gpio_irqbank(bank, isr_saved & ~level_mask);
                _enable_gpio_irqbank(bank, isr_saved & ~level_mask);

                /* if there is only edge sensitive GPIO pin interrupts
                configured, we could unmask GPIO bank interrupt immediately */
                if (!level_mask && !unmasked) {
                        unmasked = 1;
                        chained_irq_exit(chip, desc);
                }

                if (!isr)
                        break;

                while (isr) {
                        bit = __ffs(isr);
                        isr &= ~(1 << bit);

                        /*
                         * Some chips can't respond to both rising and falling
                         * at the same time.  If this irq was requested with
                         * both flags, we need to flip the ICR data for the IRQ
                         * to respond to the IRQ for the opposite direction.
                         * This will be indicated in the bank toggle_mask.
                         */
                        if (bank->toggle_mask & (1 << bit))
                                _toggle_gpio_edge_triggering(bank, bit);

                        generic_handle_irq(irq_find_mapping(bank->domain, bit));
                }
        }
        /* if bank has any level sensitive GPIO pin interrupt
        configured, we must unmask the bank interrupt only after
        handler(s) are executed in order to avoid spurious bank
        interrupt */
exit:
        if (!unmasked)
                chained_irq_exit(chip, desc);
        pm_runtime_put(bank->dev);
}

static void gpio_irq_shutdown(struct irq_data *d)
{
        struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
        unsigned int gpio = irq_to_gpio(bank, d->hwirq);
        unsigned long flags;
        unsigned offset = GPIO_INDEX(bank, gpio);

        spin_lock_irqsave(&bank->lock, flags);
        bank->irq_usage &= ~(1 << offset);
        _disable_gpio_module(bank, offset);
        _reset_gpio(bank, gpio);
        spin_unlock_irqrestore(&bank->lock, flags);

        /*
         * If this is the last IRQ to be freed in the bank,
         * disable the bank module.
         */
        if (!BANK_USED(bank))
                pm_runtime_put(bank->dev);
}

static void gpio_ack_irq(struct irq_data *d)
{
        struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
        unsigned int gpio = irq_to_gpio(bank, d->hwirq);

        _clear_gpio_irqstatus(bank, gpio);
}

static void gpio_mask_irq(struct irq_data *d)
{
        struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
        unsigned int gpio = irq_to_gpio(bank, d->hwirq);
        unsigned long flags;

        spin_lock_irqsave(&bank->lock, flags);
        _set_gpio_irqenable(bank, gpio, 0);
        _set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), IRQ_TYPE_NONE);
        spin_unlock_irqrestore(&bank->lock, flags);
}

static void gpio_unmask_irq(struct irq_data *d)
{
        struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
        unsigned int gpio = irq_to_gpio(bank, d->hwirq);
        unsigned int irq_mask = GPIO_BIT(bank, gpio);
        u32 trigger = irqd_get_trigger_type(d);
        unsigned long flags;

        spin_lock_irqsave(&bank->lock, flags);
        if (trigger)
                _set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), trigger);

        /* For level-triggered GPIOs, the clearing must be done after
         * the HW source is cleared, thus after the handler has run */
        if (bank->level_mask & irq_mask) {
                _set_gpio_irqenable(bank, gpio, 0);
                _clear_gpio_irqstatus(bank, gpio);
        }

        _set_gpio_irqenable(bank, gpio, 1);
        spin_unlock_irqrestore(&bank->lock, flags);
}

static struct irq_chip gpio_irq_chip = {
        .name           = "GPIO",
        .irq_shutdown   = gpio_irq_shutdown,
        .irq_ack        = gpio_ack_irq,
        .irq_mask       = gpio_mask_irq,
        .irq_unmask     = gpio_unmask_irq,
        .irq_set_type   = gpio_irq_type,
        .irq_set_wake   = gpio_wake_enable,
};

/*---------------------------------------------------------------------*/

static int omap_mpuio_suspend_noirq(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);
        struct gpio_bank        *bank = platform_get_drvdata(pdev);
        void __iomem            *mask_reg = bank->base +
                                        OMAP_MPUIO_GPIO_MASKIT / bank->stride;
        unsigned long           flags;

        spin_lock_irqsave(&bank->lock, flags);
        __raw_writel(0xffff & ~bank->context.wake_en, mask_reg);
        spin_unlock_irqrestore(&bank->lock, flags);

        return 0;
}

static int omap_mpuio_resume_noirq(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);
        struct gpio_bank        *bank = platform_get_drvdata(pdev);
        void __iomem            *mask_reg = bank->base +
                                        OMAP_MPUIO_GPIO_MASKIT / bank->stride;
        unsigned long           flags;

        spin_lock_irqsave(&bank->lock, flags);
        __raw_writel(bank->context.wake_en, mask_reg);
        spin_unlock_irqrestore(&bank->lock, flags);

        return 0;
}

static const struct dev_pm_ops omap_mpuio_dev_pm_ops = {
        .suspend_noirq = omap_mpuio_suspend_noirq,
        .resume_noirq = omap_mpuio_resume_noirq,
};

/* use platform_driver for this. */
static struct platform_driver omap_mpuio_driver = {
        .driver         = {
                .name   = "mpuio",
                .pm     = &omap_mpuio_dev_pm_ops,
        },
};

static struct platform_device omap_mpuio_device = {
        .name           = "mpuio",
        .id             = -1,
        .dev = {
                .driver = &omap_mpuio_driver.driver,
        }
        /* could list the /proc/iomem resources */
};

static inline void mpuio_init(struct gpio_bank *bank)
{
        platform_set_drvdata(&omap_mpuio_device, bank);

        if (platform_driver_register(&omap_mpuio_driver) == 0)
                (void) platform_device_register(&omap_mpuio_device);
}

/*---------------------------------------------------------------------*/

static int gpio_input(struct gpio_chip *chip, unsigned offset)
{
        struct gpio_bank *bank;
        unsigned long flags;

        bank = container_of(chip, struct gpio_bank, chip);
        spin_lock_irqsave(&bank->lock, flags);
        _set_gpio_direction(bank, offset, 1);
        spin_unlock_irqrestore(&bank->lock, flags);
        return 0;
}

static int gpio_get(struct gpio_chip *chip, unsigned offset)
{
        struct gpio_bank *bank;
        u32 mask;

        bank = container_of(chip, struct gpio_bank, chip);
        mask = (1 << offset);

        if (gpio_is_input(bank, mask))
                return _get_gpio_datain(bank, offset);
        else
                return _get_gpio_dataout(bank, offset);
}

static int gpio_output(struct gpio_chip *chip, unsigned offset, int value)
{
        struct gpio_bank *bank;
        unsigned long flags;
        int retval = 0;

        bank = container_of(chip, struct gpio_bank, chip);
        spin_lock_irqsave(&bank->lock, flags);

        if (LINE_USED(bank->irq_usage, offset)) {
                        retval = -EINVAL;
                        goto exit;
        }

        bank->set_dataout(bank, offset, value);
        _set_gpio_direction(bank, offset, 0);

exit:
        spin_unlock_irqrestore(&bank->lock, flags);
        return retval;
}

static int gpio_debounce(struct gpio_chip *chip, unsigned offset,
                unsigned debounce)
{
        struct gpio_bank *bank;
        unsigned long flags;

        bank = container_of(chip, struct gpio_bank, chip);

        spin_lock_irqsave(&bank->lock, flags);
        _set_gpio_debounce(bank, offset, debounce);
        spin_unlock_irqrestore(&bank->lock, flags);

        return 0;
}

static void gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
        struct gpio_bank *bank;
        unsigned long flags;

        bank = container_of(chip, struct gpio_bank, chip);
        spin_lock_irqsave(&bank->lock, flags);
        bank->set_dataout(bank, offset, value);

        spin_unlock_irqrestore(&bank->lock, flags);
}

/*---------------------------------------------------------------------*/

static void __init omap_gpio_show_rev(struct gpio_bank *bank)
{
        static bool called;
        u32 rev;

        if (called || bank->regs->revision == USHRT_MAX)
                return;

        rev = __raw_readw(bank->base + bank->regs->revision);
        pr_info("OMAP GPIO hardware version %d.%d\n",
                (rev >> 4) & 0x0f, rev & 0x0f);

        called = true;
}

/* 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 void omap_gpio_mod_init(struct gpio_bank *bank)
{
        void __iomem *base = bank->base;
        u32 l = 0xffffffff;

        if (bank->width == 16)
                l = 0xffff;

        if (bank->is_mpuio) {
                __raw_writel(l, bank->base + bank->regs->irqenable);
                return;
        }

        _gpio_rmw(base, bank->regs->irqenable, l, bank->regs->irqenable_inv);
        _gpio_rmw(base, bank->regs->irqstatus, l, !bank->regs->irqenable_inv);
        if (bank->regs->debounce_en)
                __raw_writel(0, base + bank->regs->debounce_en);

        /* Save OE default value (0xffffffff) in the context */
        bank->context.oe = __raw_readl(bank->base + bank->regs->direction);
         /* Initialize interface clk ungated, module enabled */
        if (bank->regs->ctrl)
                __raw_writel(0, base + bank->regs->ctrl);

        bank->dbck = clk_get(bank->dev, "dbclk");
        if (IS_ERR(bank->dbck))
                dev_err(bank->dev, "Could not get gpio dbck\n");
}

static void
omap_mpuio_alloc_gc(struct gpio_bank *bank, unsigned int irq_start,
                    unsigned int num)
{
        struct irq_chip_generic *gc;
        struct irq_chip_type *ct;

        gc = irq_alloc_generic_chip("MPUIO", 1, irq_start, bank->base,
                                    handle_simple_irq);
        if (!gc) {
                dev_err(bank->dev, "Memory alloc failed for gc\n");
                return;
        }

        ct = gc->chip_types;

        /* NOTE: No ack required, reading IRQ status clears it. */
        ct->chip.irq_mask = irq_gc_mask_set_bit;
        ct->chip.irq_unmask = irq_gc_mask_clr_bit;
        ct->chip.irq_set_type = gpio_irq_type;

        if (bank->regs->wkup_en)
                ct->chip.irq_set_wake = gpio_wake_enable;

        ct->regs.mask = OMAP_MPUIO_GPIO_INT / bank->stride;
        irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
                               IRQ_NOREQUEST | IRQ_NOPROBE, 0);
}

static void omap_gpio_chip_init(struct gpio_bank *bank)
{
        int j;
        static int gpio;

        /*
         * REVISIT eventually switch from OMAP-specific gpio structs
         * over to the generic ones
         */
        bank->chip.request = omap_gpio_request;
        bank->chip.free = omap_gpio_free;
        bank->chip.direction_input = gpio_input;
        bank->chip.get = gpio_get;
        bank->chip.direction_output = gpio_output;
        bank->chip.set_debounce = gpio_debounce;
        bank->chip.set = gpio_set;
        bank->chip.to_irq = omap_gpio_to_irq;
        if (bank->is_mpuio) {
                bank->chip.label = "mpuio";
                if (bank->regs->wkup_en)
                        bank->chip.dev = &omap_mpuio_device.dev;
                bank->chip.base = OMAP_MPUIO(0);
        } else {
                bank->chip.label = "gpio";
                bank->chip.base = gpio;
                gpio += bank->width;
        }
        bank->chip.ngpio = bank->width;

        gpiochip_add(&bank->chip);

        for (j = 0; j < bank->width; j++) {
                int irq = irq_create_mapping(bank->domain, j);
                irq_set_lockdep_class(irq, &gpio_lock_class);
                irq_set_chip_data(irq, bank);
                if (bank->is_mpuio) {
                        omap_mpuio_alloc_gc(bank, irq, bank->width);
                } else {
                        irq_set_chip_and_handler(irq, &gpio_irq_chip,
                                                 handle_simple_irq);
                        set_irq_flags(irq, IRQF_VALID);
                }
        }
        irq_set_chained_handler(bank->irq, gpio_irq_handler);
        irq_set_handler_data(bank->irq, bank);
}

static const struct of_device_id omap_gpio_match[];

static int omap_gpio_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct device_node *node = dev->of_node;
        const struct of_device_id *match;
        const struct omap_gpio_platform_data *pdata;
        struct resource *res;
        struct gpio_bank *bank;
#ifdef CONFIG_ARCH_OMAP1
        int irq_base;
#endif

        match = of_match_device(of_match_ptr(omap_gpio_match), dev);

        pdata = match ? match->data : dev_get_platdata(dev);
        if (!pdata)
                return -EINVAL;

        bank = devm_kzalloc(dev, sizeof(struct gpio_bank), GFP_KERNEL);
        if (!bank) {
                dev_err(dev, "Memory alloc failed\n");
                return -ENOMEM;
        }

        res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
        if (unlikely(!res)) {
                dev_err(dev, "Invalid IRQ resource\n");
                return -ENODEV;
        }

        bank->irq = res->start;
        bank->dev = dev;
        bank->dbck_flag = pdata->dbck_flag;
        bank->stride = pdata->bank_stride;
        bank->width = pdata->bank_width;
        bank->is_mpuio = pdata->is_mpuio;
        bank->non_wakeup_gpios = pdata->non_wakeup_gpios;
        bank->regs = pdata->regs;
#ifdef CONFIG_OF_GPIO
        bank->chip.of_node = of_node_get(node);
#endif
        if (node) {
                if (!of_property_read_bool(node, "ti,gpio-always-on"))
                        bank->loses_context = true;
        } else {
                bank->loses_context = pdata->loses_context;

                if (bank->loses_context)
                        bank->get_context_loss_count =
                                pdata->get_context_loss_count;
        }

#ifdef CONFIG_ARCH_OMAP1
        /*
         * REVISIT: Once we have OMAP1 supporting SPARSE_IRQ, we can drop
         * irq_alloc_descs() and irq_domain_add_legacy() and just use a
         * linear IRQ domain mapping for all OMAP platforms.
         */
        irq_base = irq_alloc_descs(-1, 0, bank->width, 0);
        if (irq_base < 0) {
                dev_err(dev, "Couldn't allocate IRQ numbers\n");
                return -ENODEV;
        }

        bank->domain = irq_domain_add_legacy(node, bank->width, irq_base,
                                             0, &irq_domain_simple_ops, NULL);
#else
        bank->domain = irq_domain_add_linear(node, bank->width,
                                             &irq_domain_simple_ops, NULL);
#endif
        if (!bank->domain) {
                dev_err(dev, "Couldn't register an IRQ domain\n");
                return -ENODEV;
        }

        if (bank->regs->set_dataout && bank->regs->clr_dataout)
                bank->set_dataout = _set_gpio_dataout_reg;
        else
                bank->set_dataout = _set_gpio_dataout_mask;

        spin_lock_init(&bank->lock);

        /* Static mapping, never released */
        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (unlikely(!res)) {
                dev_err(dev, "Invalid mem resource\n");
                irq_domain_remove(bank->domain);
                return -ENODEV;
        }

        if (!devm_request_mem_region(dev, res->start, resource_size(res),
                                     pdev->name)) {
                dev_err(dev, "Region already claimed\n");
                irq_domain_remove(bank->domain);
                return -EBUSY;
        }

        bank->base = devm_ioremap(dev, res->start, resource_size(res));
        if (!bank->base) {
                dev_err(dev, "Could not ioremap\n");
                irq_domain_remove(bank->domain);
                return -ENOMEM;
        }

        platform_set_drvdata(pdev, bank);

        pm_runtime_enable(bank->dev);
        pm_runtime_irq_safe(bank->dev);
        pm_runtime_get_sync(bank->dev);

        if (bank->is_mpuio)
                mpuio_init(bank);

        omap_gpio_mod_init(bank);
        omap_gpio_chip_init(bank);
        omap_gpio_show_rev(bank);

        pm_runtime_put(bank->dev);

        list_add_tail(&bank->node, &omap_gpio_list);

        return 0;
}

#ifdef CONFIG_ARCH_OMAP2PLUS

#if defined(CONFIG_PM_RUNTIME)
static void omap_gpio_restore_context(struct gpio_bank *bank);

static int omap_gpio_runtime_suspend(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);
        struct gpio_bank *bank = platform_get_drvdata(pdev);
        u32 l1 = 0, l2 = 0;
        unsigned long flags;
        u32 wake_low, wake_hi;

        spin_lock_irqsave(&bank->lock, flags);

        /*
         * Only edges can generate a wakeup event to the PRCM.
         *
         * Therefore, ensure any wake-up capable GPIOs have
         * edge-detection enabled before going idle to ensure a wakeup
         * to the PRCM is generated on a GPIO transition. (c.f. 34xx
         * NDA TRM 25.5.3.1)
         *
         * The normal values will be restored upon ->runtime_resume()
         * by writing back the values saved in bank->context.
         */
        wake_low = bank->context.leveldetect0 & bank->context.wake_en;
        if (wake_low)
                __raw_writel(wake_low | bank->context.fallingdetect,
                             bank->base + bank->regs->fallingdetect);
        wake_hi = bank->context.leveldetect1 & bank->context.wake_en;
        if (wake_hi)
                __raw_writel(wake_hi | bank->context.risingdetect,
                             bank->base + bank->regs->risingdetect);

        if (!bank->enabled_non_wakeup_gpios)
                goto update_gpio_context_count;

        if (bank->power_mode != OFF_MODE) {
                bank->power_mode = 0;
                goto update_gpio_context_count;
        }
        /*
         * If going to OFF, remove triggering for all
         * non-wakeup GPIOs.  Otherwise spurious IRQs will be
         * generated.  See OMAP2420 Errata item 1.101.
         */
        bank->saved_datain = __raw_readl(bank->base +
                                                bank->regs->datain);
        l1 = bank->context.fallingdetect;
        l2 = bank->context.risingdetect;

        l1 &= ~bank->enabled_non_wakeup_gpios;
        l2 &= ~bank->enabled_non_wakeup_gpios;

        __raw_writel(l1, bank->base + bank->regs->fallingdetect);
        __raw_writel(l2, bank->base + bank->regs->risingdetect);

        bank->workaround_enabled = true;

update_gpio_context_count:
        if (bank->get_context_loss_count)
                bank->context_loss_count =
                                bank->get_context_loss_count(bank->dev);

        _gpio_dbck_disable(bank);
        spin_unlock_irqrestore(&bank->lock, flags);

        return 0;
}

static void omap_gpio_init_context(struct gpio_bank *p);

static int omap_gpio_runtime_resume(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);
        struct gpio_bank *bank = platform_get_drvdata(pdev);
        u32 l = 0, gen, gen0, gen1;
        unsigned long flags;
        int c;

        spin_lock_irqsave(&bank->lock, flags);

        /*
         * On the first resume during the probe, the context has not
         * been initialised and so initialise it now. Also initialise
         * the context loss count.
         */
        if (bank->loses_context && !bank->context_valid) {
                omap_gpio_init_context(bank);

                if (bank->get_context_loss_count)
                        bank->context_loss_count =
                                bank->get_context_loss_count(bank->dev);
        }

        _gpio_dbck_enable(bank);

        /*
         * In ->runtime_suspend(), level-triggered, wakeup-enabled
         * GPIOs were set to edge trigger also in order to be able to
         * generate a PRCM wakeup.  Here we restore the
         * pre-runtime_suspend() values for edge triggering.
         */
        __raw_writel(bank->context.fallingdetect,
                     bank->base + bank->regs->fallingdetect);
        __raw_writel(bank->context.risingdetect,
                     bank->base + bank->regs->risingdetect);

        if (bank->loses_context) {
                if (!bank->get_context_loss_count) {
                        omap_gpio_restore_context(bank);
                } else {
                        c = bank->get_context_loss_count(bank->dev);
                        if (c != bank->context_loss_count) {
                                omap_gpio_restore_context(bank);
                        } else {
                                spin_unlock_irqrestore(&bank->lock, flags);
                                return 0;
                        }
                }
        }

        if (!bank->workaround_enabled) {
                spin_unlock_irqrestore(&bank->lock, flags);
                return 0;
        }

        l = __raw_readl(bank->base + bank->regs->datain);

        /*
         * Check if any of the non-wakeup interrupt GPIOs have changed
         * state.  If so, generate an IRQ by software.  This is
         * horribly racy, but it's the best we can do to work around
         * this silicon bug.
         */
        l ^= bank->saved_datain;
        l &= bank->enabled_non_wakeup_gpios;

        /*
         * No need to generate IRQs for the rising edge for gpio IRQs
         * configured with falling edge only; and vice versa.
         */
        gen0 = l & bank->context.fallingdetect;
        gen0 &= bank->saved_datain;

        gen1 = l & bank->context.risingdetect;
        gen1 &= ~(bank->saved_datain);

        /* FIXME: Consider GPIO IRQs with level detections properly! */
        gen = l & (~(bank->context.fallingdetect) &
                                         ~(bank->context.risingdetect));
        /* Consider all GPIO IRQs needed to be updated */
        gen |= gen0 | gen1;

        if (gen) {
                u32 old0, old1;

                old0 = __raw_readl(bank->base + bank->regs->leveldetect0);
                old1 = __raw_readl(bank->base + bank->regs->leveldetect1);

                if (!bank->regs->irqstatus_raw0) {
                        __raw_writel(old0 | gen, bank->base +
                                                bank->regs->leveldetect0);
                        __raw_writel(old1 | gen, bank->base +
                                                bank->regs->leveldetect1);
                }

                if (bank->regs->irqstatus_raw0) {
                        __raw_writel(old0 | l, bank->base +
                                                bank->regs->leveldetect0);
                        __raw_writel(old1 | l, bank->base +
                                                bank->regs->leveldetect1);
                }
                __raw_writel(old0, bank->base + bank->regs->leveldetect0);
                __raw_writel(old1, bank->base + bank->regs->leveldetect1);
        }

        bank->workaround_enabled = false;
        spin_unlock_irqrestore(&bank->lock, flags);

        return 0;
}
#endif /* CONFIG_PM_RUNTIME */

void omap2_gpio_prepare_for_idle(int pwr_mode)
{
        struct gpio_bank *bank;

        list_for_each_entry(bank, &omap_gpio_list, node) {
                if (!BANK_USED(bank) || !bank->loses_context)
                        continue;

                bank->power_mode = pwr_mode;

                pm_runtime_put_sync_suspend(bank->dev);
        }
}

void omap2_gpio_resume_after_idle(void)
{
        struct gpio_bank *bank;

        list_for_each_entry(bank, &omap_gpio_list, node) {
                if (!BANK_USED(bank) || !bank->loses_context)
                        continue;

                pm_runtime_get_sync(bank->dev);
        }
}

#if defined(CONFIG_PM_RUNTIME)
static void omap_gpio_init_context(struct gpio_bank *p)
{
        struct omap_gpio_reg_offs *regs = p->regs;
        void __iomem *base = p->base;

        p->context.ctrl         = __raw_readl(base + regs->ctrl);
        p->context.oe           = __raw_readl(base + regs->direction);
        p->context.wake_en      = __raw_readl(base + regs->wkup_en);
        p->context.leveldetect0 = __raw_readl(base + regs->leveldetect0);
        p->context.leveldetect1 = __raw_readl(base + regs->leveldetect1);
        p->context.risingdetect = __raw_readl(base + regs->risingdetect);
        p->context.fallingdetect = __raw_readl(base + regs->fallingdetect);
        p->context.irqenable1   = __raw_readl(base + regs->irqenable);
        p->context.irqenable2   = __raw_readl(base + regs->irqenable2);

        if (regs->set_dataout && p->regs->clr_dataout)
                p->context.dataout = __raw_readl(base + regs->set_dataout);
        else
                p->context.dataout = __raw_readl(base + regs->dataout);

        p->context_valid = true;
}

static void omap_gpio_restore_context(struct gpio_bank *bank)
{
        __raw_writel(bank->context.wake_en,
                                bank->base + bank->regs->wkup_en);
        __raw_writel(bank->context.ctrl, bank->base + bank->regs->ctrl);
        __raw_writel(bank->context.leveldetect0,
                                bank->base + bank->regs->leveldetect0);
        __raw_writel(bank->context.leveldetect1,
                                bank->base + bank->regs->leveldetect1);
        __raw_writel(bank->context.risingdetect,
                                bank->base + bank->regs->risingdetect);
        __raw_writel(bank->context.fallingdetect,
                                bank->base + bank->regs->fallingdetect);
        if (bank->regs->set_dataout && bank->regs->clr_dataout)
                __raw_writel(bank->context.dataout,
                                bank->base + bank->regs->set_dataout);
        else
                __raw_writel(bank->context.dataout,
                                bank->base + bank->regs->dataout);
        __raw_writel(bank->context.oe, bank->base + bank->regs->direction);

        if (bank->dbck_enable_mask) {
                __raw_writel(bank->context.debounce, bank->base +
                                        bank->regs->debounce);
                __raw_writel(bank->context.debounce_en,
                                        bank->base + bank->regs->debounce_en);
        }

        __raw_writel(bank->context.irqenable1,
                                bank->base + bank->regs->irqenable);
        __raw_writel(bank->context.irqenable2,
                                bank->base + bank->regs->irqenable2);
}
#endif /* CONFIG_PM_RUNTIME */
#else
#define omap_gpio_runtime_suspend NULL
#define omap_gpio_runtime_resume NULL
static inline void omap_gpio_init_context(struct gpio_bank *p) {}
#endif

static const struct dev_pm_ops gpio_pm_ops = {
        SET_RUNTIME_PM_OPS(omap_gpio_runtime_suspend, omap_gpio_runtime_resume,
                                                                        NULL)
};

#if defined(CONFIG_OF)
static struct omap_gpio_reg_offs omap2_gpio_regs = {
        .revision =             OMAP24XX_GPIO_REVISION,
        .direction =            OMAP24XX_GPIO_OE,
        .datain =               OMAP24XX_GPIO_DATAIN,
        .dataout =              OMAP24XX_GPIO_DATAOUT,
        .set_dataout =          OMAP24XX_GPIO_SETDATAOUT,
        .clr_dataout =          OMAP24XX_GPIO_CLEARDATAOUT,
        .irqstatus =            OMAP24XX_GPIO_IRQSTATUS1,
        .irqstatus2 =           OMAP24XX_GPIO_IRQSTATUS2,
        .irqenable =            OMAP24XX_GPIO_IRQENABLE1,
        .irqenable2 =           OMAP24XX_GPIO_IRQENABLE2,
        .set_irqenable =        OMAP24XX_GPIO_SETIRQENABLE1,
        .clr_irqenable =        OMAP24XX_GPIO_CLEARIRQENABLE1,
        .debounce =             OMAP24XX_GPIO_DEBOUNCE_VAL,
        .debounce_en =          OMAP24XX_GPIO_DEBOUNCE_EN,
        .ctrl =                 OMAP24XX_GPIO_CTRL,
        .wkup_en =              OMAP24XX_GPIO_WAKE_EN,
        .leveldetect0 =         OMAP24XX_GPIO_LEVELDETECT0,
        .leveldetect1 =         OMAP24XX_GPIO_LEVELDETECT1,
        .risingdetect =         OMAP24XX_GPIO_RISINGDETECT,
        .fallingdetect =        OMAP24XX_GPIO_FALLINGDETECT,
};

static struct omap_gpio_reg_offs omap4_gpio_regs = {
        .revision =             OMAP4_GPIO_REVISION,
        .direction =            OMAP4_GPIO_OE,
        .datain =               OMAP4_GPIO_DATAIN,
        .dataout =              OMAP4_GPIO_DATAOUT,
        .set_dataout =          OMAP4_GPIO_SETDATAOUT,
        .clr_dataout =          OMAP4_GPIO_CLEARDATAOUT,
        .irqstatus =            OMAP4_GPIO_IRQSTATUS0,
        .irqstatus2 =           OMAP4_GPIO_IRQSTATUS1,
        .irqenable =            OMAP4_GPIO_IRQSTATUSSET0,
        .irqenable2 =           OMAP4_GPIO_IRQSTATUSSET1,
        .set_irqenable =        OMAP4_GPIO_IRQSTATUSSET0,
        .clr_irqenable =        OMAP4_GPIO_IRQSTATUSCLR0,
        .debounce =             OMAP4_GPIO_DEBOUNCINGTIME,
        .debounce_en =          OMAP4_GPIO_DEBOUNCENABLE,
        .ctrl =                 OMAP4_GPIO_CTRL,
        .wkup_en =              OMAP4_GPIO_IRQWAKEN0,
        .leveldetect0 =         OMAP4_GPIO_LEVELDETECT0,
        .leveldetect1 =         OMAP4_GPIO_LEVELDETECT1,
        .risingdetect =         OMAP4_GPIO_RISINGDETECT,
        .fallingdetect =        OMAP4_GPIO_FALLINGDETECT,
};

static const struct omap_gpio_platform_data omap2_pdata = {
        .regs = &omap2_gpio_regs,
        .bank_width = 32,
        .dbck_flag = false,
};

static const struct omap_gpio_platform_data omap3_pdata = {
        .regs = &omap2_gpio_regs,
        .bank_width = 32,
        .dbck_flag = true,
};

static const struct omap_gpio_platform_data omap4_pdata = {
        .regs = &omap4_gpio_regs,
        .bank_width = 32,
        .dbck_flag = true,
};

static const struct of_device_id omap_gpio_match[] = {
        {
                .compatible = "ti,omap4-gpio",
                .data = &omap4_pdata,
        },
        {
                .compatible = "ti,omap3-gpio",
                .data = &omap3_pdata,
        },
        {
                .compatible = "ti,omap2-gpio",
                .data = &omap2_pdata,
        },
        { },
};
MODULE_DEVICE_TABLE(of, omap_gpio_match);
#endif

static struct platform_driver omap_gpio_driver = {
        .probe          = omap_gpio_probe,
        .driver         = {
                .name   = "omap_gpio",
                .pm     = &gpio_pm_ops,
                .of_match_table = of_match_ptr(omap_gpio_match),
        },
};

/*
 * gpio driver register needs to be done before
 * machine_init functions access gpio APIs.
 * Hence omap_gpio_drv_reg() is a postcore_initcall.
 */
static int __init omap_gpio_drv_reg(void)
{
        return platform_driver_register(&omap_gpio_driver);
}
postcore_initcall(omap_gpio_drv_reg);