Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1772 insertions, 0 deletions

diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
new file mode 100644
index 000000000..feabac407
--- /dev/null
+++ b/drivers/gpio/gpio-omap.c
@@ -0,0 +1,1772 @@
+/*
+ * 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/gpio/driver.h>
+#include <linux/bitops.h>
+#include <linux/platform_data/gpio-omap.h>
+
+#define OFF_MODE	1
+#define OMAP4_GPIO_DEBOUNCINGTIME_MASK 0xFF
+
+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;
+	int irq;
+	u32 non_wakeup_gpios;
+	u32 enabled_non_wakeup_gpios;
+	struct gpio_regs context;
+	u32 saved_datain;
+	u32 level_mask;
+	u32 toggle_mask;
+	raw_spinlock_t lock;
+	raw_spinlock_t wa_lock;
+	struct gpio_chip chip;
+	struct clk *dbck;
+	u32 mod_usage;
+	u32 irq_usage;
+	u32 dbck_enable_mask;
+	bool dbck_enabled;
+	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, unsigned gpio, int enable);
+	void (*set_dataout_multiple)(struct gpio_bank *bank,
+				     unsigned long *mask, unsigned long *bits);
+	int (*get_context_loss_count)(struct device *dev);
+
+	struct omap_gpio_reg_offs *regs;
+};
+
+#define GPIO_MOD_CTRL_BIT	BIT(0)
+
+#define BANK_USED(bank) (bank->mod_usage || bank->irq_usage)
+#define LINE_USED(line, offset) (line & (BIT(offset)))
+
+static void omap_gpio_unmask_irq(struct irq_data *d);
+
+static inline struct gpio_bank *omap_irq_data_get_bank(struct irq_data *d)
+{
+	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
+	return gpiochip_get_data(chip);
+}
+
+static void omap_set_gpio_direction(struct gpio_bank *bank, int gpio,
+				    int is_input)
+{
+	void __iomem *reg = bank->base;
+	u32 l;
+
+	reg += bank->regs->direction;
+	l = readl_relaxed(reg);
+	if (is_input)
+		l |= BIT(gpio);
+	else
+		l &= ~(BIT(gpio));
+	writel_relaxed(l, reg);
+	bank->context.oe = l;
+}
+
+
+/* set data out value using dedicate set/clear register */
+static void omap_set_gpio_dataout_reg(struct gpio_bank *bank, unsigned offset,
+				      int enable)
+{
+	void __iomem *reg = bank->base;
+	u32 l = BIT(offset);
+
+	if (enable) {
+		reg += bank->regs->set_dataout;
+		bank->context.dataout |= l;
+	} else {
+		reg += bank->regs->clr_dataout;
+		bank->context.dataout &= ~l;
+	}
+
+	writel_relaxed(l, reg);
+}
+
+/* set data out value using mask register */
+static void omap_set_gpio_dataout_mask(struct gpio_bank *bank, unsigned offset,
+				       int enable)
+{
+	void __iomem *reg = bank->base + bank->regs->dataout;
+	u32 gpio_bit = BIT(offset);
+	u32 l;
+
+	l = readl_relaxed(reg);
+	if (enable)
+		l |= gpio_bit;
+	else
+		l &= ~gpio_bit;
+	writel_relaxed(l, reg);
+	bank->context.dataout = l;
+}
+
+static int omap_get_gpio_datain(struct gpio_bank *bank, int offset)
+{
+	void __iomem *reg = bank->base + bank->regs->datain;
+
+	return (readl_relaxed(reg) & (BIT(offset))) != 0;
+}
+
+static int omap_get_gpio_dataout(struct gpio_bank *bank, int offset)
+{
+	void __iomem *reg = bank->base + bank->regs->dataout;
+
+	return (readl_relaxed(reg) & (BIT(offset))) != 0;
+}
+
+/* set multiple data out values using dedicate set/clear register */
+static void omap_set_gpio_dataout_reg_multiple(struct gpio_bank *bank,
+					       unsigned long *mask,
+					       unsigned long *bits)
+{
+	void __iomem *reg = bank->base;
+	u32 l;
+
+	l = *bits & *mask;
+	writel_relaxed(l, reg + bank->regs->set_dataout);
+	bank->context.dataout |= l;
+
+	l = ~*bits & *mask;
+	writel_relaxed(l, reg + bank->regs->clr_dataout);
+	bank->context.dataout &= ~l;
+}
+
+/* set multiple data out values using mask register */
+static void omap_set_gpio_dataout_mask_multiple(struct gpio_bank *bank,
+						unsigned long *mask,
+						unsigned long *bits)
+{
+	void __iomem *reg = bank->base + bank->regs->dataout;
+	u32 l = (readl_relaxed(reg) & ~*mask) | (*bits & *mask);
+
+	writel_relaxed(l, reg);
+	bank->context.dataout = l;
+}
+
+static unsigned long omap_get_gpio_datain_multiple(struct gpio_bank *bank,
+					      unsigned long *mask)
+{
+	void __iomem *reg = bank->base + bank->regs->datain;
+
+	return readl_relaxed(reg) & *mask;
+}
+
+static unsigned long omap_get_gpio_dataout_multiple(struct gpio_bank *bank,
+					       unsigned long *mask)
+{
+	void __iomem *reg = bank->base + bank->regs->dataout;
+
+	return readl_relaxed(reg) & *mask;
+}
+
+static inline void omap_gpio_rmw(void __iomem *base, u32 reg, u32 mask, bool set)
+{
+	int l = readl_relaxed(base + reg);
+
+	if (set)
+		l |= mask;
+	else
+		l &= ~mask;
+
+	writel_relaxed(l, base + reg);
+}
+
+static inline void omap_gpio_dbck_enable(struct gpio_bank *bank)
+{
+	if (bank->dbck_enable_mask && !bank->dbck_enabled) {
+		clk_enable(bank->dbck);
+		bank->dbck_enabled = true;
+
+		writel_relaxed(bank->dbck_enable_mask,
+			     bank->base + bank->regs->debounce_en);
+	}
+}
+
+static inline void omap_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.
+		 */
+		writel_relaxed(0, bank->base + bank->regs->debounce_en);
+
+		clk_disable(bank->dbck);
+		bank->dbck_enabled = false;
+	}
+}
+
+/**
+ * omap2_set_gpio_debounce - low level gpio debounce time
+ * @bank: the gpio bank we're acting upon
+ * @offset: the gpio number on this @bank
+ * @debounce: debounce time to use
+ *
+ * OMAP's debounce time is in 31us steps
+ *   <debounce time> = (GPIO_DEBOUNCINGTIME[7:0].DEBOUNCETIME + 1) x 31
+ * so we need to convert and round up to the closest unit.
+ *
+ * Return: 0 on success, negative error otherwise.
+ */
+static int omap2_set_gpio_debounce(struct gpio_bank *bank, unsigned offset,
+				   unsigned debounce)
+{
+	void __iomem		*reg;
+	u32			val;
+	u32			l;
+	bool			enable = !!debounce;
+
+	if (!bank->dbck_flag)
+		return -ENOTSUPP;
+
+	if (enable) {
+		debounce = DIV_ROUND_UP(debounce, 31) - 1;
+		if ((debounce & OMAP4_GPIO_DEBOUNCINGTIME_MASK) != debounce)
+			return -EINVAL;
+	}
+
+	l = BIT(offset);
+
+	clk_enable(bank->dbck);
+	reg = bank->base + bank->regs->debounce;
+	writel_relaxed(debounce, reg);
+
+	reg = bank->base + bank->regs->debounce_en;
+	val = readl_relaxed(reg);
+
+	if (enable)
+		val |= l;
+	else
+		val &= ~l;
+	bank->dbck_enable_mask = val;
+
+	writel_relaxed(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.
+	 */
+	omap_gpio_dbck_enable(bank);
+	if (bank->dbck_enable_mask) {
+		bank->context.debounce = debounce;
+		bank->context.debounce_en = val;
+	}
+
+	return 0;
+}
+
+/**
+ * omap_clear_gpio_debounce - clear debounce settings for a gpio
+ * @bank: the gpio bank we're acting upon
+ * @offset: the gpio number on this @bank
+ *
+ * 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 omap_clear_gpio_debounce(struct gpio_bank *bank, unsigned offset)
+{
+	u32 gpio_bit = BIT(offset);
+
+	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;
+        writel_relaxed(bank->context.debounce_en,
+		     bank->base + bank->regs->debounce_en);
+
+	if (!bank->dbck_enable_mask) {
+		bank->context.debounce = 0;
+		writel_relaxed(bank->context.debounce, bank->base +
+			     bank->regs->debounce);
+		clk_disable(bank->dbck);
+		bank->dbck_enabled = false;
+	}
+}
+
+/*
+ * Off mode wake-up capable GPIOs in bank(s) that are in the wakeup domain.
+ * See TRM section for GPIO for "Wake-Up Generation" for the list of GPIOs
+ * in wakeup domain. If bank->non_wakeup_gpios is not configured, assume none
+ * are capable waking up the system from off mode.
+ */
+static bool omap_gpio_is_off_wakeup_capable(struct gpio_bank *bank, u32 gpio_mask)
+{
+	u32 no_wake = bank->non_wakeup_gpios;
+
+	if (no_wake)
+		return !!(~no_wake & gpio_mask);
+
+	return false;
+}
+
+static inline void omap_set_gpio_trigger(struct gpio_bank *bank, int gpio,
+						unsigned trigger)
+{
+	void __iomem *base = bank->base;
+	u32 gpio_bit = BIT(gpio);
+
+	omap_gpio_rmw(base, bank->regs->leveldetect0, gpio_bit,
+		      trigger & IRQ_TYPE_LEVEL_LOW);
+	omap_gpio_rmw(base, bank->regs->leveldetect1, gpio_bit,
+		      trigger & IRQ_TYPE_LEVEL_HIGH);
+	omap_gpio_rmw(base, bank->regs->risingdetect, gpio_bit,
+		      trigger & IRQ_TYPE_EDGE_RISING);
+	omap_gpio_rmw(base, bank->regs->fallingdetect, gpio_bit,
+		      trigger & IRQ_TYPE_EDGE_FALLING);
+
+	bank->context.leveldetect0 =
+			readl_relaxed(bank->base + bank->regs->leveldetect0);
+	bank->context.leveldetect1 =
+			readl_relaxed(bank->base + bank->regs->leveldetect1);
+	bank->context.risingdetect =
+			readl_relaxed(bank->base + bank->regs->risingdetect);
+	bank->context.fallingdetect =
+			readl_relaxed(bank->base + bank->regs->fallingdetect);
+
+	if (likely(!(bank->non_wakeup_gpios & gpio_bit))) {
+		omap_gpio_rmw(base, bank->regs->wkup_en, gpio_bit, trigger != 0);
+		bank->context.wake_en =
+			readl_relaxed(bank->base + bank->regs->wkup_en);
+	}
+
+	/* This part needs to be executed always for OMAP{34xx, 44xx} */
+	if (!bank->regs->irqctrl && !omap_gpio_is_off_wakeup_capable(bank, gpio)) {
+		/*
+		 * 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;
+	}
+
+	bank->level_mask =
+		readl_relaxed(bank->base + bank->regs->leveldetect0) |
+		readl_relaxed(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 omap_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 = readl_relaxed(reg);
+	if ((l >> gpio) & 1)
+		l &= ~(BIT(gpio));
+	else
+		l |= BIT(gpio);
+
+	writel_relaxed(l, reg);
+}
+#else
+static void omap_toggle_gpio_edge_triggering(struct gpio_bank *bank, int gpio) {}
+#endif
+
+static int omap_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) {
+		omap_set_gpio_trigger(bank, gpio, trigger);
+	} else if (bank->regs->irqctrl) {
+		reg += bank->regs->irqctrl;
+
+		l = readl_relaxed(reg);
+		if ((trigger & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH)
+			bank->toggle_mask |= BIT(gpio);
+		if (trigger & IRQ_TYPE_EDGE_RISING)
+			l |= BIT(gpio);
+		else if (trigger & IRQ_TYPE_EDGE_FALLING)
+			l &= ~(BIT(gpio));
+		else
+			return -EINVAL;
+
+		writel_relaxed(l, reg);
+	} else if (bank->regs->edgectrl1) {
+		if (gpio & 0x08)
+			reg += bank->regs->edgectrl2;
+		else
+			reg += bank->regs->edgectrl1;
+
+		gpio &= 0x07;
+		l = readl_relaxed(reg);
+		l &= ~(3 << (gpio << 1));
+		if (trigger & IRQ_TYPE_EDGE_RISING)
+			l |= 2 << (gpio << 1);
+		if (trigger & IRQ_TYPE_EDGE_FALLING)
+			l |= BIT(gpio << 1);
+
+		/* Enable wake-up during idle for dynamic tick */
+		omap_gpio_rmw(base, bank->regs->wkup_en, BIT(gpio), trigger);
+		bank->context.wake_en =
+			readl_relaxed(bank->base + bank->regs->wkup_en);
+		writel_relaxed(l, reg);
+	}
+	return 0;
+}
+
+static void omap_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 */
+		writel_relaxed(readl_relaxed(reg) | (BIT(offset)), reg);
+	}
+
+	if (bank->regs->ctrl && !BANK_USED(bank)) {
+		void __iomem *reg = bank->base + bank->regs->ctrl;
+		u32 ctrl;
+
+		ctrl = readl_relaxed(reg);
+		/* Module is enabled, clocks are not gated */
+		ctrl &= ~GPIO_MOD_CTRL_BIT;
+		writel_relaxed(ctrl, reg);
+		bank->context.ctrl = ctrl;
+	}
+}
+
+static void omap_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 */
+		omap_gpio_rmw(base, bank->regs->wkup_en, BIT(offset), 0);
+		bank->context.wake_en =
+			readl_relaxed(bank->base + bank->regs->wkup_en);
+	}
+
+	if (bank->regs->ctrl && !BANK_USED(bank)) {
+		void __iomem *reg = bank->base + bank->regs->ctrl;
+		u32 ctrl;
+
+		ctrl = readl_relaxed(reg);
+		/* Module is disabled, clocks are gated */
+		ctrl |= GPIO_MOD_CTRL_BIT;
+		writel_relaxed(ctrl, reg);
+		bank->context.ctrl = ctrl;
+	}
+}
+
+static int omap_gpio_is_input(struct gpio_bank *bank, unsigned offset)
+{
+	void __iomem *reg = bank->base + bank->regs->direction;
+
+	return readl_relaxed(reg) & BIT(offset);
+}
+
+static void omap_gpio_init_irq(struct gpio_bank *bank, unsigned offset)
+{
+	if (!LINE_USED(bank->mod_usage, offset)) {
+		omap_enable_gpio_module(bank, offset);
+		omap_set_gpio_direction(bank, offset, 1);
+	}
+	bank->irq_usage |= BIT(offset);
+}
+
+static int omap_gpio_irq_type(struct irq_data *d, unsigned type)
+{
+	struct gpio_bank *bank = omap_irq_data_get_bank(d);
+	int retval;
+	unsigned long flags;
+	unsigned offset = 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;
+
+	raw_spin_lock_irqsave(&bank->lock, flags);
+	retval = omap_set_gpio_triggering(bank, offset, type);
+	if (retval) {
+		raw_spin_unlock_irqrestore(&bank->lock, flags);
+		goto error;
+	}
+	omap_gpio_init_irq(bank, offset);
+	if (!omap_gpio_is_input(bank, offset)) {
+		raw_spin_unlock_irqrestore(&bank->lock, flags);
+		retval = -EINVAL;
+		goto error;
+	}
+	raw_spin_unlock_irqrestore(&bank->lock, flags);
+
+	if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
+		irq_set_handler_locked(d, handle_level_irq);
+	else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
+		/*
+		 * Edge IRQs are already cleared/acked in irq_handler and
+		 * not need to be masked, as result handle_edge_irq()
+		 * logic is excessed here and may cause lose of interrupts.
+		 * So just use handle_simple_irq.
+		 */
+		irq_set_handler_locked(d, handle_simple_irq);
+
+	return 0;
+
+error:
+	return retval;
+}
+
+static void omap_clear_gpio_irqbank(struct gpio_bank *bank, int gpio_mask)
+{
+	void __iomem *reg = bank->base;
+
+	reg += bank->regs->irqstatus;
+	writel_relaxed(gpio_mask, reg);
+
+	/* Workaround for clearing DSP GPIO interrupts to allow retention */
+	if (bank->regs->irqstatus2) {
+		reg = bank->base + bank->regs->irqstatus2;
+		writel_relaxed(gpio_mask, reg);
+	}
+
+	/* Flush posted write for the irq status to avoid spurious interrupts */
+	readl_relaxed(reg);
+}
+
+static inline void omap_clear_gpio_irqstatus(struct gpio_bank *bank,
+					     unsigned offset)
+{
+	omap_clear_gpio_irqbank(bank, BIT(offset));
+}
+
+static u32 omap_get_gpio_irqbank_mask(struct gpio_bank *bank)
+{
+	void __iomem *reg = bank->base;
+	u32 l;
+	u32 mask = (BIT(bank->width)) - 1;
+
+	reg += bank->regs->irqenable;
+	l = readl_relaxed(reg);
+	if (bank->regs->irqenable_inv)
+		l = ~l;
+	l &= mask;
+	return l;
+}
+
+static void omap_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 = readl_relaxed(reg);
+		if (bank->regs->irqenable_inv)
+			l &= ~gpio_mask;
+		else
+			l |= gpio_mask;
+		bank->context.irqenable1 = l;
+	}
+
+	writel_relaxed(l, reg);
+}
+
+static void omap_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 = readl_relaxed(reg);
+		if (bank->regs->irqenable_inv)
+			l |= gpio_mask;
+		else
+			l &= ~gpio_mask;
+		bank->context.irqenable1 = l;
+	}
+
+	writel_relaxed(l, reg);
+}
+
+static inline void omap_set_gpio_irqenable(struct gpio_bank *bank,
+					   unsigned offset, int enable)
+{
+	if (enable)
+		omap_enable_gpio_irqbank(bank, BIT(offset));
+	else
+		omap_disable_gpio_irqbank(bank, BIT(offset));
+}
+
+/* Use disable_irq_wake() and enable_irq_wake() functions from drivers */
+static int omap_gpio_wake_enable(struct irq_data *d, unsigned int enable)
+{
+	struct gpio_bank *bank = omap_irq_data_get_bank(d);
+
+	return irq_set_irq_wake(bank->irq, enable);
+}
+
+static int omap_gpio_request(struct gpio_chip *chip, unsigned offset)
+{
+	struct gpio_bank *bank = gpiochip_get_data(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(chip->parent);
+
+	raw_spin_lock_irqsave(&bank->lock, flags);
+	omap_enable_gpio_module(bank, offset);
+	bank->mod_usage |= BIT(offset);
+	raw_spin_unlock_irqrestore(&bank->lock, flags);
+
+	return 0;
+}
+
+static void omap_gpio_free(struct gpio_chip *chip, unsigned offset)
+{
+	struct gpio_bank *bank = gpiochip_get_data(chip);
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&bank->lock, flags);
+	bank->mod_usage &= ~(BIT(offset));
+	if (!LINE_USED(bank->irq_usage, offset)) {
+		omap_set_gpio_direction(bank, offset, 1);
+		omap_clear_gpio_debounce(bank, offset);
+	}
+	omap_disable_gpio_module(bank, offset);
+	raw_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(chip->parent);
+}
+
+/*
+ * 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 irqreturn_t omap_gpio_irq_handler(int irq, void *gpiobank)
+{
+	void __iomem *isr_reg = NULL;
+	u32 enabled, isr, level_mask;
+	unsigned int bit;
+	struct gpio_bank *bank = gpiobank;
+	unsigned long wa_lock_flags;
+	unsigned long lock_flags;
+
+	isr_reg = bank->base + bank->regs->irqstatus;
+	if (WARN_ON(!isr_reg))
+		goto exit;
+
+	pm_runtime_get_sync(bank->chip.parent);
+
+	while (1) {
+		raw_spin_lock_irqsave(&bank->lock, lock_flags);
+
+		enabled = omap_get_gpio_irqbank_mask(bank);
+		isr = readl_relaxed(isr_reg) & enabled;
+
+		if (bank->level_mask)
+			level_mask = bank->level_mask & enabled;
+		else
+			level_mask = 0;
+
+		/* clear edge sensitive interrupts before handler(s) are
+		called so that we don't miss any interrupt occurred while
+		executing them */
+		if (isr & ~level_mask)
+			omap_clear_gpio_irqbank(bank, isr & ~level_mask);
+
+		raw_spin_unlock_irqrestore(&bank->lock, lock_flags);
+
+		if (!isr)
+			break;
+
+		while (isr) {
+			bit = __ffs(isr);
+			isr &= ~(BIT(bit));
+
+			raw_spin_lock_irqsave(&bank->lock, lock_flags);
+			/*
+			 * 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 & (BIT(bit)))
+				omap_toggle_gpio_edge_triggering(bank, bit);
+
+			raw_spin_unlock_irqrestore(&bank->lock, lock_flags);
+
+			raw_spin_lock_irqsave(&bank->wa_lock, wa_lock_flags);
+
+			generic_handle_irq(irq_find_mapping(bank->chip.irq.domain,
+							    bit));
+
+			raw_spin_unlock_irqrestore(&bank->wa_lock,
+						   wa_lock_flags);
+		}
+	}
+exit:
+	pm_runtime_put(bank->chip.parent);
+	return IRQ_HANDLED;
+}
+
+static unsigned int omap_gpio_irq_startup(struct irq_data *d)
+{
+	struct gpio_bank *bank = omap_irq_data_get_bank(d);
+	unsigned long flags;
+	unsigned offset = d->hwirq;
+
+	raw_spin_lock_irqsave(&bank->lock, flags);
+
+	if (!LINE_USED(bank->mod_usage, offset))
+		omap_set_gpio_direction(bank, offset, 1);
+	else if (!omap_gpio_is_input(bank, offset))
+		goto err;
+	omap_enable_gpio_module(bank, offset);
+	bank->irq_usage |= BIT(offset);
+
+	raw_spin_unlock_irqrestore(&bank->lock, flags);
+	omap_gpio_unmask_irq(d);
+
+	return 0;
+err:
+	raw_spin_unlock_irqrestore(&bank->lock, flags);
+	return -EINVAL;
+}
+
+static void omap_gpio_irq_shutdown(struct irq_data *d)
+{
+	struct gpio_bank *bank = omap_irq_data_get_bank(d);
+	unsigned long flags;
+	unsigned offset = d->hwirq;
+
+	raw_spin_lock_irqsave(&bank->lock, flags);
+	bank->irq_usage &= ~(BIT(offset));
+	omap_set_gpio_triggering(bank, offset, IRQ_TYPE_NONE);
+	omap_clear_gpio_irqstatus(bank, offset);
+	omap_set_gpio_irqenable(bank, offset, 0);
+	if (!LINE_USED(bank->mod_usage, offset))
+		omap_clear_gpio_debounce(bank, offset);
+	omap_disable_gpio_module(bank, offset);
+	raw_spin_unlock_irqrestore(&bank->lock, flags);
+}
+
+static void omap_gpio_irq_bus_lock(struct irq_data *data)
+{
+	struct gpio_bank *bank = omap_irq_data_get_bank(data);
+
+	if (!BANK_USED(bank))
+		pm_runtime_get_sync(bank->chip.parent);
+}
+
+static void gpio_irq_bus_sync_unlock(struct irq_data *data)
+{
+	struct gpio_bank *bank = omap_irq_data_get_bank(data);
+
+	/*
+	 * If this is the last IRQ to be freed in the bank,
+	 * disable the bank module.
+	 */
+	if (!BANK_USED(bank))
+		pm_runtime_put(bank->chip.parent);
+}
+
+static void omap_gpio_ack_irq(struct irq_data *d)
+{
+	struct gpio_bank *bank = omap_irq_data_get_bank(d);
+	unsigned offset = d->hwirq;
+
+	omap_clear_gpio_irqstatus(bank, offset);
+}
+
+static void omap_gpio_mask_irq(struct irq_data *d)
+{
+	struct gpio_bank *bank = omap_irq_data_get_bank(d);
+	unsigned offset = d->hwirq;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&bank->lock, flags);
+	omap_set_gpio_triggering(bank, offset, IRQ_TYPE_NONE);
+	omap_set_gpio_irqenable(bank, offset, 0);
+	raw_spin_unlock_irqrestore(&bank->lock, flags);
+}
+
+static void omap_gpio_unmask_irq(struct irq_data *d)
+{
+	struct gpio_bank *bank = omap_irq_data_get_bank(d);
+	unsigned offset = d->hwirq;
+	u32 trigger = irqd_get_trigger_type(d);
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&bank->lock, flags);
+	omap_set_gpio_irqenable(bank, offset, 1);
+
+	/*
+	 * For level-triggered GPIOs, clearing must be done after the source
+	 * is cleared, thus after the handler has run. OMAP4 needs this done
+	 * after enabing the interrupt to clear the wakeup status.
+	 */
+	if (bank->regs->leveldetect0 && bank->regs->wkup_en &&
+	    trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
+		omap_clear_gpio_irqstatus(bank, offset);
+
+	if (trigger)
+		omap_set_gpio_triggering(bank, offset, trigger);
+
+	raw_spin_unlock_irqrestore(&bank->lock, flags);
+}
+
+/*---------------------------------------------------------------------*/
+
+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;
+
+	raw_spin_lock_irqsave(&bank->lock, flags);
+	writel_relaxed(0xffff & ~bank->context.wake_en, mask_reg);
+	raw_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;
+
+	raw_spin_lock_irqsave(&bank->lock, flags);
+	writel_relaxed(bank->context.wake_en, mask_reg);
+	raw_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 omap_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 omap_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
+{
+	struct gpio_bank *bank;
+	unsigned long flags;
+	void __iomem *reg;
+	int dir;
+
+	bank = gpiochip_get_data(chip);
+	reg = bank->base + bank->regs->direction;
+	raw_spin_lock_irqsave(&bank->lock, flags);
+	dir = !!(readl_relaxed(reg) & BIT(offset));
+	raw_spin_unlock_irqrestore(&bank->lock, flags);
+	return dir;
+}
+
+static int omap_gpio_input(struct gpio_chip *chip, unsigned offset)
+{
+	struct gpio_bank *bank;
+	unsigned long flags;
+
+	bank = gpiochip_get_data(chip);
+	raw_spin_lock_irqsave(&bank->lock, flags);
+	omap_set_gpio_direction(bank, offset, 1);
+	raw_spin_unlock_irqrestore(&bank->lock, flags);
+	return 0;
+}
+
+static int omap_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+	struct gpio_bank *bank;
+
+	bank = gpiochip_get_data(chip);
+
+	if (omap_gpio_is_input(bank, offset))
+		return omap_get_gpio_datain(bank, offset);
+	else
+		return omap_get_gpio_dataout(bank, offset);
+}
+
+static int omap_gpio_output(struct gpio_chip *chip, unsigned offset, int value)
+{
+	struct gpio_bank *bank;
+	unsigned long flags;
+
+	bank = gpiochip_get_data(chip);
+	raw_spin_lock_irqsave(&bank->lock, flags);
+	bank->set_dataout(bank, offset, value);
+	omap_set_gpio_direction(bank, offset, 0);
+	raw_spin_unlock_irqrestore(&bank->lock, flags);
+	return 0;
+}
+
+static int omap_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask,
+				  unsigned long *bits)
+{
+	struct gpio_bank *bank = gpiochip_get_data(chip);
+	void __iomem *reg = bank->base + bank->regs->direction;
+	unsigned long in = readl_relaxed(reg), l;
+
+	*bits = 0;
+
+	l = in & *mask;
+	if (l)
+		*bits |= omap_get_gpio_datain_multiple(bank, &l);
+
+	l = ~in & *mask;
+	if (l)
+		*bits |= omap_get_gpio_dataout_multiple(bank, &l);
+
+	return 0;
+}
+
+static int omap_gpio_debounce(struct gpio_chip *chip, unsigned offset,
+			      unsigned debounce)
+{
+	struct gpio_bank *bank;
+	unsigned long flags;
+	int ret;
+
+	bank = gpiochip_get_data(chip);
+
+	raw_spin_lock_irqsave(&bank->lock, flags);
+	ret = omap2_set_gpio_debounce(bank, offset, debounce);
+	raw_spin_unlock_irqrestore(&bank->lock, flags);
+
+	if (ret)
+		dev_info(chip->parent,
+			 "Could not set line %u debounce to %u microseconds (%d)",
+			 offset, debounce, ret);
+
+	return ret;
+}
+
+static int omap_gpio_set_config(struct gpio_chip *chip, unsigned offset,
+				unsigned long config)
+{
+	u32 debounce;
+
+	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
+		return -ENOTSUPP;
+
+	debounce = pinconf_to_config_argument(config);
+	return omap_gpio_debounce(chip, offset, debounce);
+}
+
+static void omap_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+	struct gpio_bank *bank;
+	unsigned long flags;
+
+	bank = gpiochip_get_data(chip);
+	raw_spin_lock_irqsave(&bank->lock, flags);
+	bank->set_dataout(bank, offset, value);
+	raw_spin_unlock_irqrestore(&bank->lock, flags);
+}
+
+static void omap_gpio_set_multiple(struct gpio_chip *chip, unsigned long *mask,
+				   unsigned long *bits)
+{
+	struct gpio_bank *bank = gpiochip_get_data(chip);
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&bank->lock, flags);
+	bank->set_dataout_multiple(bank, mask, bits);
+	raw_spin_unlock_irqrestore(&bank->lock, flags);
+}
+
+/*---------------------------------------------------------------------*/
+
+static void omap_gpio_show_rev(struct gpio_bank *bank)
+{
+	static bool called;
+	u32 rev;
+
+	if (called || bank->regs->revision == USHRT_MAX)
+		return;
+
+	rev = readw_relaxed(bank->base + bank->regs->revision);
+	pr_info("OMAP GPIO hardware version %d.%d\n",
+		(rev >> 4) & 0x0f, rev & 0x0f);
+
+	called = true;
+}
+
+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) {
+		writel_relaxed(l, bank->base + bank->regs->irqenable);
+		return;
+	}
+
+	omap_gpio_rmw(base, bank->regs->irqenable, l,
+		      bank->regs->irqenable_inv);
+	omap_gpio_rmw(base, bank->regs->irqstatus, l,
+		      !bank->regs->irqenable_inv);
+	if (bank->regs->debounce_en)
+		writel_relaxed(0, base + bank->regs->debounce_en);
+
+	/* Save OE default value (0xffffffff) in the context */
+	bank->context.oe = readl_relaxed(bank->base + bank->regs->direction);
+	 /* Initialize interface clk ungated, module enabled */
+	if (bank->regs->ctrl)
+		writel_relaxed(0, base + bank->regs->ctrl);
+}
+
+static int omap_gpio_chip_init(struct gpio_bank *bank, struct irq_chip *irqc)
+{
+	struct gpio_irq_chip *irq;
+	static int gpio;
+	const char *label;
+	int irq_base = 0;
+	int ret;
+
+	/*
+	 * 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.get_direction = omap_gpio_get_direction;
+	bank->chip.direction_input = omap_gpio_input;
+	bank->chip.get = omap_gpio_get;
+	bank->chip.get_multiple = omap_gpio_get_multiple;
+	bank->chip.direction_output = omap_gpio_output;
+	bank->chip.set_config = omap_gpio_set_config;
+	bank->chip.set = omap_gpio_set;
+	bank->chip.set_multiple = omap_gpio_set_multiple;
+	if (bank->is_mpuio) {
+		bank->chip.label = "mpuio";
+		if (bank->regs->wkup_en)
+			bank->chip.parent = &omap_mpuio_device.dev;
+		bank->chip.base = OMAP_MPUIO(0);
+	} else {
+		label = devm_kasprintf(bank->chip.parent, GFP_KERNEL, "gpio-%d-%d",
+				       gpio, gpio + bank->width - 1);
+		if (!label)
+			return -ENOMEM;
+		bank->chip.label = label;
+		bank->chip.base = gpio;
+	}
+	bank->chip.ngpio = bank->width;
+
+#ifdef CONFIG_ARCH_OMAP1
+	/*
+	 * REVISIT: Once we have OMAP1 supporting SPARSE_IRQ, we can drop
+	 * irq_alloc_descs() since a base IRQ offset will no longer be needed.
+	 */
+	irq_base = devm_irq_alloc_descs(bank->chip.parent,
+					-1, 0, bank->width, 0);
+	if (irq_base < 0) {
+		dev_err(bank->chip.parent, "Couldn't allocate IRQ numbers\n");
+		return -ENODEV;
+	}
+#endif
+
+	/* MPUIO is a bit different, reading IRQ status clears it */
+	if (bank->is_mpuio) {
+		irqc->irq_ack = dummy_irq_chip.irq_ack;
+		if (!bank->regs->wkup_en)
+			irqc->irq_set_wake = NULL;
+	}
+
+	irq = &bank->chip.irq;
+	irq->chip = irqc;
+	irq->handler = handle_bad_irq;
+	irq->default_type = IRQ_TYPE_NONE;
+	irq->num_parents = 1;
+	irq->parents = &bank->irq;
+	irq->first = irq_base;
+
+	ret = gpiochip_add_data(&bank->chip, bank);
+	if (ret) {
+		dev_err(bank->chip.parent,
+			"Could not register gpio chip %d\n", ret);
+		return ret;
+	}
+
+	ret = devm_request_irq(bank->chip.parent, bank->irq,
+			       omap_gpio_irq_handler,
+			       0, dev_name(bank->chip.parent), bank);
+	if (ret)
+		gpiochip_remove(&bank->chip);
+
+	if (!bank->is_mpuio)
+		gpio += bank->width;
+
+	return ret;
+}
+
+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;
+	struct irq_chip *irqc;
+	int ret;
+
+	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(*bank), GFP_KERNEL);
+	if (!bank)
+		return -ENOMEM;
+
+	irqc = devm_kzalloc(dev, sizeof(*irqc), GFP_KERNEL);
+	if (!irqc)
+		return -ENOMEM;
+
+	irqc->irq_startup = omap_gpio_irq_startup,
+	irqc->irq_shutdown = omap_gpio_irq_shutdown,
+	irqc->irq_ack = omap_gpio_ack_irq,
+	irqc->irq_mask = omap_gpio_mask_irq,
+	irqc->irq_unmask = omap_gpio_unmask_irq,
+	irqc->irq_set_type = omap_gpio_irq_type,
+	irqc->irq_set_wake = omap_gpio_wake_enable,
+	irqc->irq_bus_lock = omap_gpio_irq_bus_lock,
+	irqc->irq_bus_sync_unlock = gpio_irq_bus_sync_unlock,
+	irqc->name = dev_name(&pdev->dev);
+	irqc->flags = IRQCHIP_MASK_ON_SUSPEND;
+
+	bank->irq = platform_get_irq(pdev, 0);
+	if (bank->irq <= 0) {
+		if (!bank->irq)
+			bank->irq = -ENXIO;
+		if (bank->irq != -EPROBE_DEFER)
+			dev_err(dev,
+				"can't get irq resource ret=%d\n", bank->irq);
+		return bank->irq;
+	}
+
+	bank->chip.parent = dev;
+	bank->chip.owner = THIS_MODULE;
+	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;
+	}
+
+	if (bank->regs->set_dataout && bank->regs->clr_dataout) {
+		bank->set_dataout = omap_set_gpio_dataout_reg;
+		bank->set_dataout_multiple = omap_set_gpio_dataout_reg_multiple;
+	} else {
+		bank->set_dataout = omap_set_gpio_dataout_mask;
+		bank->set_dataout_multiple =
+				omap_set_gpio_dataout_mask_multiple;
+	}
+
+	raw_spin_lock_init(&bank->lock);
+	raw_spin_lock_init(&bank->wa_lock);
+
+	/* Static mapping, never released */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	bank->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(bank->base)) {
+		return PTR_ERR(bank->base);
+	}
+
+	if (bank->dbck_flag) {
+		bank->dbck = devm_clk_get(dev, "dbclk");
+		if (IS_ERR(bank->dbck)) {
+			dev_err(dev,
+				"Could not get gpio dbck. Disable debounce\n");
+			bank->dbck_flag = false;
+		} else {
+			clk_prepare(bank->dbck);
+		}
+	}
+
+	platform_set_drvdata(pdev, bank);
+
+	pm_runtime_enable(dev);
+	pm_runtime_irq_safe(dev);
+	pm_runtime_get_sync(dev);
+
+	if (bank->is_mpuio)
+		omap_mpuio_init(bank);
+
+	omap_gpio_mod_init(bank);
+
+	ret = omap_gpio_chip_init(bank, irqc);
+	if (ret) {
+		pm_runtime_put_sync(dev);
+		pm_runtime_disable(dev);
+		if (bank->dbck_flag)
+			clk_unprepare(bank->dbck);
+		return ret;
+	}
+
+	omap_gpio_show_rev(bank);
+
+	pm_runtime_put(dev);
+
+	list_add_tail(&bank->node, &omap_gpio_list);
+
+	return 0;
+}
+
+static int omap_gpio_remove(struct platform_device *pdev)
+{
+	struct gpio_bank *bank = platform_get_drvdata(pdev);
+
+	list_del(&bank->node);
+	gpiochip_remove(&bank->chip);
+	pm_runtime_disable(&pdev->dev);
+	if (bank->dbck_flag)
+		clk_unprepare(bank->dbck);
+
+	return 0;
+}
+
+#ifdef CONFIG_ARCH_OMAP2PLUS
+
+#if defined(CONFIG_PM)
+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;
+
+	raw_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)
+		writel_relaxed(wake_low | bank->context.fallingdetect,
+			     bank->base + bank->regs->fallingdetect);
+	wake_hi = bank->context.leveldetect1 & bank->context.wake_en;
+	if (wake_hi)
+		writel_relaxed(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 = readl_relaxed(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;
+
+	writel_relaxed(l1, bank->base + bank->regs->fallingdetect);
+	writel_relaxed(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(dev);
+
+	omap_gpio_dbck_disable(bank);
+	raw_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;
+
+	raw_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(dev);
+	}
+
+	omap_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.
+	 */
+	writel_relaxed(bank->context.fallingdetect,
+		     bank->base + bank->regs->fallingdetect);
+	writel_relaxed(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(dev);
+			if (c != bank->context_loss_count) {
+				omap_gpio_restore_context(bank);
+			} else {
+				raw_spin_unlock_irqrestore(&bank->lock, flags);
+				return 0;
+			}
+		}
+	}
+
+	if (!bank->workaround_enabled) {
+		raw_spin_unlock_irqrestore(&bank->lock, flags);
+		return 0;
+	}
+
+	l = readl_relaxed(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 = readl_relaxed(bank->base + bank->regs->leveldetect0);
+		old1 = readl_relaxed(bank->base + bank->regs->leveldetect1);
+
+		if (!bank->regs->irqstatus_raw0) {
+			writel_relaxed(old0 | gen, bank->base +
+						bank->regs->leveldetect0);
+			writel_relaxed(old1 | gen, bank->base +
+						bank->regs->leveldetect1);
+		}
+
+		if (bank->regs->irqstatus_raw0) {
+			writel_relaxed(old0 | l, bank->base +
+						bank->regs->leveldetect0);
+			writel_relaxed(old1 | l, bank->base +
+						bank->regs->leveldetect1);
+		}
+		writel_relaxed(old0, bank->base + bank->regs->leveldetect0);
+		writel_relaxed(old1, bank->base + bank->regs->leveldetect1);
+	}
+
+	bank->workaround_enabled = false;
+	raw_spin_unlock_irqrestore(&bank->lock, flags);
+
+	return 0;
+}
+#endif /* CONFIG_PM */
+
+#if IS_BUILTIN(CONFIG_GPIO_OMAP)
+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->chip.parent);
+	}
+}
+
+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->chip.parent);
+	}
+}
+#endif
+
+#if defined(CONFIG_PM)
+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		= readl_relaxed(base + regs->ctrl);
+	p->context.oe		= readl_relaxed(base + regs->direction);
+	p->context.wake_en	= readl_relaxed(base + regs->wkup_en);
+	p->context.leveldetect0	= readl_relaxed(base + regs->leveldetect0);
+	p->context.leveldetect1	= readl_relaxed(base + regs->leveldetect1);
+	p->context.risingdetect	= readl_relaxed(base + regs->risingdetect);
+	p->context.fallingdetect = readl_relaxed(base + regs->fallingdetect);
+	p->context.irqenable1	= readl_relaxed(base + regs->irqenable);
+	p->context.irqenable2	= readl_relaxed(base + regs->irqenable2);
+
+	if (regs->set_dataout && p->regs->clr_dataout)
+		p->context.dataout = readl_relaxed(base + regs->set_dataout);
+	else
+		p->context.dataout = readl_relaxed(base + regs->dataout);
+
+	p->context_valid = true;
+}
+
+static void omap_gpio_restore_context(struct gpio_bank *bank)
+{
+	writel_relaxed(bank->context.wake_en,
+				bank->base + bank->regs->wkup_en);
+	writel_relaxed(bank->context.ctrl, bank->base + bank->regs->ctrl);
+	writel_relaxed(bank->context.leveldetect0,
+				bank->base + bank->regs->leveldetect0);
+	writel_relaxed(bank->context.leveldetect1,
+				bank->base + bank->regs->leveldetect1);
+	writel_relaxed(bank->context.risingdetect,
+				bank->base + bank->regs->risingdetect);
+	writel_relaxed(bank->context.fallingdetect,
+				bank->base + bank->regs->fallingdetect);
+	if (bank->regs->set_dataout && bank->regs->clr_dataout)
+		writel_relaxed(bank->context.dataout,
+				bank->base + bank->regs->set_dataout);
+	else
+		writel_relaxed(bank->context.dataout,
+				bank->base + bank->regs->dataout);
+	writel_relaxed(bank->context.oe, bank->base + bank->regs->direction);
+
+	if (bank->dbck_enable_mask) {
+		writel_relaxed(bank->context.debounce, bank->base +
+					bank->regs->debounce);
+		writel_relaxed(bank->context.debounce_en,
+					bank->base + bank->regs->debounce_en);
+	}
+
+	writel_relaxed(bank->context.irqenable1,
+				bank->base + bank->regs->irqenable);
+	writel_relaxed(bank->context.irqenable2,
+				bank->base + bank->regs->irqenable2);
+}
+#endif /* CONFIG_PM */
+#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,
+	.irqstatus_raw0 =	OMAP4_GPIO_IRQSTATUSRAW0,
+	.irqstatus_raw1 =	OMAP4_GPIO_IRQSTATUSRAW1,
+	.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,
+	.remove		= omap_gpio_remove,
+	.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);
+
+static void __exit omap_gpio_exit(void)
+{
+	platform_driver_unregister(&omap_gpio_driver);
+}
+module_exit(omap_gpio_exit);
+
+MODULE_DESCRIPTION("omap gpio driver");
+MODULE_ALIAS("platform:gpio-omap");
+MODULE_LICENSE("GPL v2");