gpio: move Nomadik GPIO driver to drivers/gpio

This moves the Nomadik GPIO driver out of arch/arm/plat-nomadik
and into the desired location indicated by the subsystem
maintainer.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
[grant.likely: squashed with kconfig fixup]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

2 files changed, 1021 insertions, 0 deletions

diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 27a22086739b..7481e7da2adb 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -35,6 +35,7 @@ obj-$(CONFIG_GPIO_WM8350)	+= wm8350-gpiolib.o
 obj-$(CONFIG_GPIO_WM8994)       += wm8994-gpio.o
 obj-$(CONFIG_GPIO_SCH)          += sch_gpio.o
 obj-$(CONFIG_MACH_U300)         += gpio-u300.o
+obj-$(CONFIG_PLAT_NOMADIK)      += gpio-nomadik.o
 obj-$(CONFIG_GPIO_RDC321X)      += rdc321x-gpio.o
 obj-$(CONFIG_GPIO_JANZ_TTL)     += janz-ttl.o
 obj-$(CONFIG_GPIO_SX150X)       += sx150x.o
diff --git a/drivers/gpio/gpio-nomadik.c b/drivers/gpio/gpio-nomadik.c
new file mode 100644
index 000000000000..307b8131aa8c
--- /dev/null
+++ b/drivers/gpio/gpio-nomadik.c
@@ -0,0 +1,1020 @@
+/*
+ * Generic GPIO driver for logic cells found in the Nomadik SoC
+ *
+ * Copyright (C) 2008,2009 STMicroelectronics
+ * Copyright (C) 2009 Alessandro Rubini <rubini@unipv.it>
+ *   Rewritten based on work by Prafulla WADASKAR <prafulla.wadaskar@st.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/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/slab.h>
+
+#include <asm/mach/irq.h>
+
+#include <plat/pincfg.h>
+#include <mach/hardware.h>
+#include <mach/gpio.h>
+
+/*
+ * The GPIO module in the Nomadik family of Systems-on-Chip is an
+ * AMBA device, managing 32 pins and alternate functions.  The logic block
+ * is currently used in the Nomadik and ux500.
+ *
+ * Symbols in this file are called "nmk_gpio" for "nomadik gpio"
+ */
+
+#define NMK_GPIO_PER_CHIP       32
+
+struct nmk_gpio_chip {
+        struct gpio_chip chip;
+        void __iomem *addr;
+        struct clk *clk;
+        unsigned int bank;
+        unsigned int parent_irq;
+        int secondary_parent_irq;
+        u32 (*get_secondary_status)(unsigned int bank);
+        void (*set_ioforce)(bool enable);
+        spinlock_t lock;
+        /* Keep track of configured edges */
+        u32 edge_rising;
+        u32 edge_falling;
+        u32 real_wake;
+        u32 rwimsc;
+        u32 fwimsc;
+        u32 slpm;
+        u32 enabled;
+};
+
+static struct nmk_gpio_chip *
+nmk_gpio_chips[DIV_ROUND_UP(ARCH_NR_GPIOS, NMK_GPIO_PER_CHIP)];
+
+static DEFINE_SPINLOCK(nmk_gpio_slpm_lock);
+
+#define NUM_BANKS ARRAY_SIZE(nmk_gpio_chips)
+
+static void __nmk_gpio_set_mode(struct nmk_gpio_chip *nmk_chip,
+                                unsigned offset, int gpio_mode)
+{
+        u32 bit = 1 << offset;
+        u32 afunc, bfunc;
+
+        afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & ~bit;
+        bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & ~bit;
+        if (gpio_mode & NMK_GPIO_ALT_A)
+                afunc |= bit;
+        if (gpio_mode & NMK_GPIO_ALT_B)
+                bfunc |= bit;
+        writel(afunc, nmk_chip->addr + NMK_GPIO_AFSLA);
+        writel(bfunc, nmk_chip->addr + NMK_GPIO_AFSLB);
+}
+
+static void __nmk_gpio_set_slpm(struct nmk_gpio_chip *nmk_chip,
+                                unsigned offset, enum nmk_gpio_slpm mode)
+{
+        u32 bit = 1 << offset;
+        u32 slpm;
+
+        slpm = readl(nmk_chip->addr + NMK_GPIO_SLPC);
+        if (mode == NMK_GPIO_SLPM_NOCHANGE)
+                slpm |= bit;
+        else
+                slpm &= ~bit;
+        writel(slpm, nmk_chip->addr + NMK_GPIO_SLPC);
+}
+
+static void __nmk_gpio_set_pull(struct nmk_gpio_chip *nmk_chip,
+                                unsigned offset, enum nmk_gpio_pull pull)
+{
+        u32 bit = 1 << offset;
+        u32 pdis;
+
+        pdis = readl(nmk_chip->addr + NMK_GPIO_PDIS);
+        if (pull == NMK_GPIO_PULL_NONE)
+                pdis |= bit;
+        else
+                pdis &= ~bit;
+        writel(pdis, nmk_chip->addr + NMK_GPIO_PDIS);
+
+        if (pull == NMK_GPIO_PULL_UP)
+                writel(bit, nmk_chip->addr + NMK_GPIO_DATS);
+        else if (pull == NMK_GPIO_PULL_DOWN)
+                writel(bit, nmk_chip->addr + NMK_GPIO_DATC);
+}
+
+static void __nmk_gpio_make_input(struct nmk_gpio_chip *nmk_chip,
+                                  unsigned offset)
+{
+        writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRC);
+}
+
+static void __nmk_gpio_set_output(struct nmk_gpio_chip *nmk_chip,
+                                  unsigned offset, int val)
+{
+        if (val)
+                writel(1 << offset, nmk_chip->addr + NMK_GPIO_DATS);
+        else
+                writel(1 << offset, nmk_chip->addr + NMK_GPIO_DATC);
+}
+
+static void __nmk_gpio_make_output(struct nmk_gpio_chip *nmk_chip,
+                                  unsigned offset, int val)
+{
+        writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRS);
+        __nmk_gpio_set_output(nmk_chip, offset, val);
+}
+
+static void __nmk_gpio_set_mode_safe(struct nmk_gpio_chip *nmk_chip,
+                                     unsigned offset, int gpio_mode,
+                                     bool glitch)
+{
+        u32 rwimsc = readl(nmk_chip->addr + NMK_GPIO_RWIMSC);
+        u32 fwimsc = readl(nmk_chip->addr + NMK_GPIO_FWIMSC);
+
+        if (glitch && nmk_chip->set_ioforce) {
+                u32 bit = BIT(offset);
+
+                /* Prevent spurious wakeups */
+                writel(rwimsc & ~bit, nmk_chip->addr + NMK_GPIO_RWIMSC);
+                writel(fwimsc & ~bit, nmk_chip->addr + NMK_GPIO_FWIMSC);
+
+                nmk_chip->set_ioforce(true);
+        }
+
+        __nmk_gpio_set_mode(nmk_chip, offset, gpio_mode);
+
+        if (glitch && nmk_chip->set_ioforce) {
+                nmk_chip->set_ioforce(false);
+
+                writel(rwimsc, nmk_chip->addr + NMK_GPIO_RWIMSC);
+                writel(fwimsc, nmk_chip->addr + NMK_GPIO_FWIMSC);
+        }
+}
+
+static void __nmk_config_pin(struct nmk_gpio_chip *nmk_chip, unsigned offset,
+                             pin_cfg_t cfg, bool sleep, unsigned int *slpmregs)
+{
+        static const char *afnames[] = {
+                [NMK_GPIO_ALT_GPIO]     = "GPIO",
+                [NMK_GPIO_ALT_A]        = "A",
+                [NMK_GPIO_ALT_B]        = "B",
+                [NMK_GPIO_ALT_C]        = "C"
+        };
+        static const char *pullnames[] = {
+                [NMK_GPIO_PULL_NONE]    = "none",
+                [NMK_GPIO_PULL_UP]      = "up",
+                [NMK_GPIO_PULL_DOWN]    = "down",
+                [3] /* illegal */       = "??"
+        };
+        static const char *slpmnames[] = {
+                [NMK_GPIO_SLPM_INPUT]           = "input/wakeup",
+                [NMK_GPIO_SLPM_NOCHANGE]        = "no-change/no-wakeup",
+        };
+
+        int pin = PIN_NUM(cfg);
+        int pull = PIN_PULL(cfg);
+        int af = PIN_ALT(cfg);
+        int slpm = PIN_SLPM(cfg);
+        int output = PIN_DIR(cfg);
+        int val = PIN_VAL(cfg);
+        bool glitch = af == NMK_GPIO_ALT_C;
+
+        dev_dbg(nmk_chip->chip.dev, "pin %d [%#lx]: af %s, pull %s, slpm %s (%s%s)\n",
+                pin, cfg, afnames[af], pullnames[pull], slpmnames[slpm],
+                output ? "output " : "input",
+                output ? (val ? "high" : "low") : "");
+
+        if (sleep) {
+                int slpm_pull = PIN_SLPM_PULL(cfg);
+                int slpm_output = PIN_SLPM_DIR(cfg);
+                int slpm_val = PIN_SLPM_VAL(cfg);
+
+                af = NMK_GPIO_ALT_GPIO;
+
+                /*
+                 * The SLPM_* values are normal values + 1 to allow zero to
+                 * mean "same as normal".
+                 */
+                if (slpm_pull)
+                        pull = slpm_pull - 1;
+                if (slpm_output)
+                        output = slpm_output - 1;
+                if (slpm_val)
+                        val = slpm_val - 1;
+
+                dev_dbg(nmk_chip->chip.dev, "pin %d: sleep pull %s, dir %s, val %s\n",
+                        pin,
+                        slpm_pull ? pullnames[pull] : "same",
+                        slpm_output ? (output ? "output" : "input") : "same",
+                        slpm_val ? (val ? "high" : "low") : "same");
+        }
+
+        if (output)
+                __nmk_gpio_make_output(nmk_chip, offset, val);
+        else {
+                __nmk_gpio_make_input(nmk_chip, offset);
+                __nmk_gpio_set_pull(nmk_chip, offset, pull);
+        }
+
+        /*
+         * If we've backed up the SLPM registers (glitch workaround), modify
+         * the backups since they will be restored.
+         */
+        if (slpmregs) {
+                if (slpm == NMK_GPIO_SLPM_NOCHANGE)
+                        slpmregs[nmk_chip->bank] |= BIT(offset);
+                else
+                        slpmregs[nmk_chip->bank] &= ~BIT(offset);
+        } else
+                __nmk_gpio_set_slpm(nmk_chip, offset, slpm);
+
+        __nmk_gpio_set_mode_safe(nmk_chip, offset, af, glitch);
+}
+
+/*
+ * Safe sequence used to switch IOs between GPIO and Alternate-C mode:
+ *  - Save SLPM registers
+ *  - Set SLPM=0 for the IOs you want to switch and others to 1
+ *  - Configure the GPIO registers for the IOs that are being switched
+ *  - Set IOFORCE=1
+ *  - Modify the AFLSA/B registers for the IOs that are being switched
+ *  - Set IOFORCE=0
+ *  - Restore SLPM registers
+ *  - Any spurious wake up event during switch sequence to be ignored and
+ *    cleared
+ */
+static void nmk_gpio_glitch_slpm_init(unsigned int *slpm)
+{
+        int i;
+
+        for (i = 0; i < NUM_BANKS; i++) {
+                struct nmk_gpio_chip *chip = nmk_gpio_chips[i];
+                unsigned int temp = slpm[i];
+
+                if (!chip)
+                        break;
+
+                slpm[i] = readl(chip->addr + NMK_GPIO_SLPC);
+                writel(temp, chip->addr + NMK_GPIO_SLPC);
+        }
+}
+
+static void nmk_gpio_glitch_slpm_restore(unsigned int *slpm)
+{
+        int i;
+
+        for (i = 0; i < NUM_BANKS; i++) {
+                struct nmk_gpio_chip *chip = nmk_gpio_chips[i];
+
+                if (!chip)
+                        break;
+
+                writel(slpm[i], chip->addr + NMK_GPIO_SLPC);
+        }
+}
+
+static int __nmk_config_pins(pin_cfg_t *cfgs, int num, bool sleep)
+{
+        static unsigned int slpm[NUM_BANKS];
+        unsigned long flags;
+        bool glitch = false;
+        int ret = 0;
+        int i;
+
+        for (i = 0; i < num; i++) {
+                if (PIN_ALT(cfgs[i]) == NMK_GPIO_ALT_C) {
+                        glitch = true;
+                        break;
+                }
+        }
+
+        spin_lock_irqsave(&nmk_gpio_slpm_lock, flags);
+
+        if (glitch) {
+                memset(slpm, 0xff, sizeof(slpm));
+
+                for (i = 0; i < num; i++) {
+                        int pin = PIN_NUM(cfgs[i]);
+                        int offset = pin % NMK_GPIO_PER_CHIP;
+
+                        if (PIN_ALT(cfgs[i]) == NMK_GPIO_ALT_C)
+                                slpm[pin / NMK_GPIO_PER_CHIP] &= ~BIT(offset);
+                }
+
+                nmk_gpio_glitch_slpm_init(slpm);
+        }
+
+        for (i = 0; i < num; i++) {
+                struct nmk_gpio_chip *nmk_chip;
+                int pin = PIN_NUM(cfgs[i]);
+
+                nmk_chip = irq_get_chip_data(NOMADIK_GPIO_TO_IRQ(pin));
+                if (!nmk_chip) {
+                        ret = -EINVAL;
+                        break;
+                }
+
+                spin_lock(&nmk_chip->lock);
+                __nmk_config_pin(nmk_chip, pin - nmk_chip->chip.base,
+                                 cfgs[i], sleep, glitch ? slpm : NULL);
+                spin_unlock(&nmk_chip->lock);
+        }
+
+        if (glitch)
+                nmk_gpio_glitch_slpm_restore(slpm);
+
+        spin_unlock_irqrestore(&nmk_gpio_slpm_lock, flags);
+
+        return ret;
+}
+
+/**
+ * nmk_config_pin - configure a pin's mux attributes
+ * @cfg: pin confguration
+ *
+ * Configures a pin's mode (alternate function or GPIO), its pull up status,
+ * and its sleep mode based on the specified configuration.  The @cfg is
+ * usually one of the SoC specific macros defined in mach/<soc>-pins.h.  These
+ * are constructed using, and can be further enhanced with, the macros in
+ * plat/pincfg.h.
+ *
+ * If a pin's mode is set to GPIO, it is configured as an input to avoid
+ * side-effects.  The gpio can be manipulated later using standard GPIO API
+ * calls.
+ */
+int nmk_config_pin(pin_cfg_t cfg, bool sleep)
+{
+        return __nmk_config_pins(&cfg, 1, sleep);
+}
+EXPORT_SYMBOL(nmk_config_pin);
+
+/**
+ * nmk_config_pins - configure several pins at once
+ * @cfgs: array of pin configurations
+ * @num: number of elments in the array
+ *
+ * Configures several pins using nmk_config_pin().  Refer to that function for
+ * further information.
+ */
+int nmk_config_pins(pin_cfg_t *cfgs, int num)
+{
+        return __nmk_config_pins(cfgs, num, false);
+}
+EXPORT_SYMBOL(nmk_config_pins);
+
+int nmk_config_pins_sleep(pin_cfg_t *cfgs, int num)
+{
+        return __nmk_config_pins(cfgs, num, true);
+}
+EXPORT_SYMBOL(nmk_config_pins_sleep);
+
+/**
+ * nmk_gpio_set_slpm() - configure the sleep mode of a pin
+ * @gpio: pin number
+ * @mode: NMK_GPIO_SLPM_INPUT or NMK_GPIO_SLPM_NOCHANGE,
+ *
+ * Sets the sleep mode of a pin.  If @mode is NMK_GPIO_SLPM_INPUT, the pin is
+ * changed to an input (with pullup/down enabled) in sleep and deep sleep.  If
+ * @mode is NMK_GPIO_SLPM_NOCHANGE, the pin remains in the state it was
+ * configured even when in sleep and deep sleep.
+ *
+ * On DB8500v2 onwards, this setting loses the previous meaning and instead
+ * indicates if wakeup detection is enabled on the pin.  Note that
+ * enable_irq_wake() will automatically enable wakeup detection.
+ */
+int nmk_gpio_set_slpm(int gpio, enum nmk_gpio_slpm mode)
+{
+        struct nmk_gpio_chip *nmk_chip;
+        unsigned long flags;
+
+        nmk_chip = irq_get_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));
+        if (!nmk_chip)
+                return -EINVAL;
+
+        spin_lock_irqsave(&nmk_gpio_slpm_lock, flags);
+        spin_lock(&nmk_chip->lock);
+
+        __nmk_gpio_set_slpm(nmk_chip, gpio - nmk_chip->chip.base, mode);
+
+        spin_unlock(&nmk_chip->lock);
+        spin_unlock_irqrestore(&nmk_gpio_slpm_lock, flags);
+
+        return 0;
+}
+
+/**
+ * nmk_gpio_set_pull() - enable/disable pull up/down on a gpio
+ * @gpio: pin number
+ * @pull: one of NMK_GPIO_PULL_DOWN, NMK_GPIO_PULL_UP, and NMK_GPIO_PULL_NONE
+ *
+ * Enables/disables pull up/down on a specified pin.  This only takes effect if
+ * the pin is configured as an input (either explicitly or by the alternate
+ * function).
+ *
+ * NOTE: If enabling the pull up/down, the caller must ensure that the GPIO is
+ * configured as an input.  Otherwise, due to the way the controller registers
+ * work, this function will change the value output on the pin.
+ */
+int nmk_gpio_set_pull(int gpio, enum nmk_gpio_pull pull)
+{
+        struct nmk_gpio_chip *nmk_chip;
+        unsigned long flags;
+
+        nmk_chip = irq_get_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));
+        if (!nmk_chip)
+                return -EINVAL;
+
+        spin_lock_irqsave(&nmk_chip->lock, flags);
+        __nmk_gpio_set_pull(nmk_chip, gpio - nmk_chip->chip.base, pull);
+        spin_unlock_irqrestore(&nmk_chip->lock, flags);
+
+        return 0;
+}
+
+/* Mode functions */
+/**
+ * nmk_gpio_set_mode() - set the mux mode of a gpio pin
+ * @gpio: pin number
+ * @gpio_mode: one of NMK_GPIO_ALT_GPIO, NMK_GPIO_ALT_A,
+ *             NMK_GPIO_ALT_B, and NMK_GPIO_ALT_C
+ *
+ * Sets the mode of the specified pin to one of the alternate functions or
+ * plain GPIO.
+ */
+int nmk_gpio_set_mode(int gpio, int gpio_mode)
+{
+        struct nmk_gpio_chip *nmk_chip;
+        unsigned long flags;
+
+        nmk_chip = irq_get_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));
+        if (!nmk_chip)
+                return -EINVAL;
+
+        spin_lock_irqsave(&nmk_chip->lock, flags);
+        __nmk_gpio_set_mode(nmk_chip, gpio - nmk_chip->chip.base, gpio_mode);
+        spin_unlock_irqrestore(&nmk_chip->lock, flags);
+
+        return 0;
+}
+EXPORT_SYMBOL(nmk_gpio_set_mode);
+
+int nmk_gpio_get_mode(int gpio)
+{
+        struct nmk_gpio_chip *nmk_chip;
+        u32 afunc, bfunc, bit;
+
+        nmk_chip = irq_get_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));
+        if (!nmk_chip)
+                return -EINVAL;
+
+        bit = 1 << (gpio - nmk_chip->chip.base);
+
+        afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & bit;
+        bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & bit;
+
+        return (afunc ? NMK_GPIO_ALT_A : 0) | (bfunc ? NMK_GPIO_ALT_B : 0);
+}
+EXPORT_SYMBOL(nmk_gpio_get_mode);
+
+
+/* IRQ functions */
+static inline int nmk_gpio_get_bitmask(int gpio)
+{
+        return 1 << (gpio % 32);
+}
+
+static void nmk_gpio_irq_ack(struct irq_data *d)
+{
+        int gpio;
+        struct nmk_gpio_chip *nmk_chip;
+
+        gpio = NOMADIK_IRQ_TO_GPIO(d->irq);
+        nmk_chip = irq_data_get_irq_chip_data(d);
+        if (!nmk_chip)
+                return;
+        writel(nmk_gpio_get_bitmask(gpio), nmk_chip->addr + NMK_GPIO_IC);
+}
+
+enum nmk_gpio_irq_type {
+        NORMAL,
+        WAKE,
+};
+
+static void __nmk_gpio_irq_modify(struct nmk_gpio_chip *nmk_chip,
+                                  int gpio, enum nmk_gpio_irq_type which,
+                                  bool enable)
+{
+        u32 rimsc = which == WAKE ? NMK_GPIO_RWIMSC : NMK_GPIO_RIMSC;
+        u32 fimsc = which == WAKE ? NMK_GPIO_FWIMSC : NMK_GPIO_FIMSC;
+        u32 bitmask = nmk_gpio_get_bitmask(gpio);
+        u32 reg;
+
+        /* we must individually set/clear the two edges */
+        if (nmk_chip->edge_rising & bitmask) {
+                reg = readl(nmk_chip->addr + rimsc);
+                if (enable)
+                        reg |= bitmask;
+                else
+                        reg &= ~bitmask;
+                writel(reg, nmk_chip->addr + rimsc);
+        }
+        if (nmk_chip->edge_falling & bitmask) {
+                reg = readl(nmk_chip->addr + fimsc);
+                if (enable)
+                        reg |= bitmask;
+                else
+                        reg &= ~bitmask;
+                writel(reg, nmk_chip->addr + fimsc);
+        }
+}
+
+static void __nmk_gpio_set_wake(struct nmk_gpio_chip *nmk_chip,
+                                int gpio, bool on)
+{
+        __nmk_gpio_irq_modify(nmk_chip, gpio, WAKE, on);
+}
+
+static int nmk_gpio_irq_maskunmask(struct irq_data *d, bool enable)
+{
+        int gpio;
+        struct nmk_gpio_chip *nmk_chip;
+        unsigned long flags;
+        u32 bitmask;
+
+        gpio = NOMADIK_IRQ_TO_GPIO(d->irq);
+        nmk_chip = irq_data_get_irq_chip_data(d);
+        bitmask = nmk_gpio_get_bitmask(gpio);
+        if (!nmk_chip)
+                return -EINVAL;
+
+        if (enable)
+                nmk_chip->enabled |= bitmask;
+        else
+                nmk_chip->enabled &= ~bitmask;
+
+        spin_lock_irqsave(&nmk_gpio_slpm_lock, flags);
+        spin_lock(&nmk_chip->lock);
+
+        __nmk_gpio_irq_modify(nmk_chip, gpio, NORMAL, enable);
+
+        if (!(nmk_chip->real_wake & bitmask))
+                __nmk_gpio_set_wake(nmk_chip, gpio, enable);
+
+        spin_unlock(&nmk_chip->lock);
+        spin_unlock_irqrestore(&nmk_gpio_slpm_lock, flags);
+
+        return 0;
+}
+
+static void nmk_gpio_irq_mask(struct irq_data *d)
+{
+        nmk_gpio_irq_maskunmask(d, false);
+}
+
+static void nmk_gpio_irq_unmask(struct irq_data *d)
+{
+        nmk_gpio_irq_maskunmask(d, true);
+}
+
+static int nmk_gpio_irq_set_wake(struct irq_data *d, unsigned int on)
+{
+        struct nmk_gpio_chip *nmk_chip;
+        unsigned long flags;
+        u32 bitmask;
+        int gpio;
+
+        gpio = NOMADIK_IRQ_TO_GPIO(d->irq);
+        nmk_chip = irq_data_get_irq_chip_data(d);
+        if (!nmk_chip)
+                return -EINVAL;
+        bitmask = nmk_gpio_get_bitmask(gpio);
+
+        spin_lock_irqsave(&nmk_gpio_slpm_lock, flags);
+        spin_lock(&nmk_chip->lock);
+
+        if (!(nmk_chip->enabled & bitmask))
+                __nmk_gpio_set_wake(nmk_chip, gpio, on);
+
+        if (on)
+                nmk_chip->real_wake |= bitmask;
+        else
+                nmk_chip->real_wake &= ~bitmask;
+
+        spin_unlock(&nmk_chip->lock);
+        spin_unlock_irqrestore(&nmk_gpio_slpm_lock, flags);
+
+        return 0;
+}
+
+static int nmk_gpio_irq_set_type(struct irq_data *d, unsigned int type)
+{
+        bool enabled, wake = irqd_is_wakeup_set(d);
+        int gpio;
+        struct nmk_gpio_chip *nmk_chip;
+        unsigned long flags;
+        u32 bitmask;
+
+        gpio = NOMADIK_IRQ_TO_GPIO(d->irq);
+        nmk_chip = irq_data_get_irq_chip_data(d);
+        bitmask = nmk_gpio_get_bitmask(gpio);
+        if (!nmk_chip)
+                return -EINVAL;
+
+        if (type & IRQ_TYPE_LEVEL_HIGH)
+                return -EINVAL;
+        if (type & IRQ_TYPE_LEVEL_LOW)
+                return -EINVAL;
+
+        enabled = nmk_chip->enabled & bitmask;
+
+        spin_lock_irqsave(&nmk_chip->lock, flags);
+
+        if (enabled)
+                __nmk_gpio_irq_modify(nmk_chip, gpio, NORMAL, false);
+
+        if (enabled || wake)
+                __nmk_gpio_irq_modify(nmk_chip, gpio, WAKE, false);
+
+        nmk_chip->edge_rising &= ~bitmask;
+        if (type & IRQ_TYPE_EDGE_RISING)
+                nmk_chip->edge_rising |= bitmask;
+
+        nmk_chip->edge_falling &= ~bitmask;
+        if (type & IRQ_TYPE_EDGE_FALLING)
+                nmk_chip->edge_falling |= bitmask;
+
+        if (enabled)
+                __nmk_gpio_irq_modify(nmk_chip, gpio, NORMAL, true);
+
+        if (enabled || wake)
+                __nmk_gpio_irq_modify(nmk_chip, gpio, WAKE, true);
+
+        spin_unlock_irqrestore(&nmk_chip->lock, flags);
+
+        return 0;
+}
+
+static struct irq_chip nmk_gpio_irq_chip = {
+        .name           = "Nomadik-GPIO",
+        .irq_ack        = nmk_gpio_irq_ack,
+        .irq_mask       = nmk_gpio_irq_mask,
+        .irq_unmask     = nmk_gpio_irq_unmask,
+        .irq_set_type   = nmk_gpio_irq_set_type,
+        .irq_set_wake   = nmk_gpio_irq_set_wake,
+};
+
+static void __nmk_gpio_irq_handler(unsigned int irq, struct irq_desc *desc,
+                                   u32 status)
+{
+        struct nmk_gpio_chip *nmk_chip;
+        struct irq_chip *host_chip = irq_get_chip(irq);
+        unsigned int first_irq;
+
+        chained_irq_enter(host_chip, desc);
+
+        nmk_chip = irq_get_handler_data(irq);
+        first_irq = NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base);
+        while (status) {
+                int bit = __ffs(status);
+
+                generic_handle_irq(first_irq + bit);
+                status &= ~BIT(bit);
+        }
+
+        chained_irq_exit(host_chip, desc);
+}
+
+static void nmk_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+        struct nmk_gpio_chip *nmk_chip = irq_get_handler_data(irq);
+        u32 status = readl(nmk_chip->addr + NMK_GPIO_IS);
+
+        __nmk_gpio_irq_handler(irq, desc, status);
+}
+
+static void nmk_gpio_secondary_irq_handler(unsigned int irq,
+                                           struct irq_desc *desc)
+{
+        struct nmk_gpio_chip *nmk_chip = irq_get_handler_data(irq);
+        u32 status = nmk_chip->get_secondary_status(nmk_chip->bank);
+
+        __nmk_gpio_irq_handler(irq, desc, status);
+}
+
+static int nmk_gpio_init_irq(struct nmk_gpio_chip *nmk_chip)
+{
+        unsigned int first_irq;
+        int i;
+
+        first_irq = NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base);
+        for (i = first_irq; i < first_irq + nmk_chip->chip.ngpio; i++) {
+                irq_set_chip_and_handler(i, &nmk_gpio_irq_chip,
+                                         handle_edge_irq);
+                set_irq_flags(i, IRQF_VALID);
+                irq_set_chip_data(i, nmk_chip);
+                irq_set_irq_type(i, IRQ_TYPE_EDGE_FALLING);
+        }
+
+        irq_set_chained_handler(nmk_chip->parent_irq, nmk_gpio_irq_handler);
+        irq_set_handler_data(nmk_chip->parent_irq, nmk_chip);
+
+        if (nmk_chip->secondary_parent_irq >= 0) {
+                irq_set_chained_handler(nmk_chip->secondary_parent_irq,
+                                        nmk_gpio_secondary_irq_handler);
+                irq_set_handler_data(nmk_chip->secondary_parent_irq, nmk_chip);
+        }
+
+        return 0;
+}
+
+/* I/O Functions */
+static int nmk_gpio_make_input(struct gpio_chip *chip, unsigned offset)
+{
+        struct nmk_gpio_chip *nmk_chip =
+                container_of(chip, struct nmk_gpio_chip, chip);
+
+        writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRC);
+        return 0;
+}
+
+static int nmk_gpio_get_input(struct gpio_chip *chip, unsigned offset)
+{
+        struct nmk_gpio_chip *nmk_chip =
+                container_of(chip, struct nmk_gpio_chip, chip);
+        u32 bit = 1 << offset;
+
+        return (readl(nmk_chip->addr + NMK_GPIO_DAT) & bit) != 0;
+}
+
+static void nmk_gpio_set_output(struct gpio_chip *chip, unsigned offset,
+                                int val)
+{
+        struct nmk_gpio_chip *nmk_chip =
+                container_of(chip, struct nmk_gpio_chip, chip);
+
+        __nmk_gpio_set_output(nmk_chip, offset, val);
+}
+
+static int nmk_gpio_make_output(struct gpio_chip *chip, unsigned offset,
+                                int val)
+{
+        struct nmk_gpio_chip *nmk_chip =
+                container_of(chip, struct nmk_gpio_chip, chip);
+
+        __nmk_gpio_make_output(nmk_chip, offset, val);
+
+        return 0;
+}
+
+static int nmk_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+        struct nmk_gpio_chip *nmk_chip =
+                container_of(chip, struct nmk_gpio_chip, chip);
+
+        return NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base) + offset;
+}
+
+#ifdef CONFIG_DEBUG_FS
+
+#include <linux/seq_file.h>
+
+static void nmk_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
+{
+        int mode;
+        unsigned                i;
+        unsigned                gpio = chip->base;
+        int                     is_out;
+        struct nmk_gpio_chip *nmk_chip =
+                container_of(chip, struct nmk_gpio_chip, chip);
+        const char *modes[] = {
+                [NMK_GPIO_ALT_GPIO]     = "gpio",
+                [NMK_GPIO_ALT_A]        = "altA",
+                [NMK_GPIO_ALT_B]        = "altB",
+                [NMK_GPIO_ALT_C]        = "altC",
+        };
+
+        for (i = 0; i < chip->ngpio; i++, gpio++) {
+                const char *label = gpiochip_is_requested(chip, i);
+                bool pull;
+                u32 bit = 1 << i;
+
+                if (!label)
+                        continue;
+
+                is_out = readl(nmk_chip->addr + NMK_GPIO_DIR) & bit;
+                pull = !(readl(nmk_chip->addr + NMK_GPIO_PDIS) & bit);
+                mode = nmk_gpio_get_mode(gpio);
+                seq_printf(s, " gpio-%-3d (%-20.20s) %s %s %s %s",
+                        gpio, label,
+                        is_out ? "out" : "in ",
+                        chip->get
+                                ? (chip->get(chip, i) ? "hi" : "lo")
+                                : "?  ",
+                        (mode < 0) ? "unknown" : modes[mode],
+                        pull ? "pull" : "none");
+                seq_printf(s, "\n");
+        }
+}
+
+#else
+#define nmk_gpio_dbg_show       NULL
+#endif
+
+/* This structure is replicated for each GPIO block allocated at probe time */
+static struct gpio_chip nmk_gpio_template = {
+        .direction_input        = nmk_gpio_make_input,
+        .get                    = nmk_gpio_get_input,
+        .direction_output       = nmk_gpio_make_output,
+        .set                    = nmk_gpio_set_output,
+        .to_irq                 = nmk_gpio_to_irq,
+        .dbg_show               = nmk_gpio_dbg_show,
+        .can_sleep              = 0,
+};
+
+/*
+ * Called from the suspend/resume path to only keep the real wakeup interrupts
+ * (those that have had set_irq_wake() called on them) as wakeup interrupts,
+ * and not the rest of the interrupts which we needed to have as wakeups for
+ * cpuidle.
+ *
+ * PM ops are not used since this needs to be done at the end, after all the
+ * other drivers are done with their suspend callbacks.
+ */
+void nmk_gpio_wakeups_suspend(void)
+{
+        int i;
+
+        for (i = 0; i < NUM_BANKS; i++) {
+                struct nmk_gpio_chip *chip = nmk_gpio_chips[i];
+
+                if (!chip)
+                        break;
+
+                chip->rwimsc = readl(chip->addr + NMK_GPIO_RWIMSC);
+                chip->fwimsc = readl(chip->addr + NMK_GPIO_FWIMSC);
+
+                writel(chip->rwimsc & chip->real_wake,
+                       chip->addr + NMK_GPIO_RWIMSC);
+                writel(chip->fwimsc & chip->real_wake,
+                       chip->addr + NMK_GPIO_FWIMSC);
+
+                if (cpu_is_u8500v2()) {
+                        chip->slpm = readl(chip->addr + NMK_GPIO_SLPC);
+
+                        /* 0 -> wakeup enable */
+                        writel(~chip->real_wake, chip->addr + NMK_GPIO_SLPC);
+                }
+        }
+}
+
+void nmk_gpio_wakeups_resume(void)
+{
+        int i;
+
+        for (i = 0; i < NUM_BANKS; i++) {
+                struct nmk_gpio_chip *chip = nmk_gpio_chips[i];
+
+                if (!chip)
+                        break;
+
+                writel(chip->rwimsc, chip->addr + NMK_GPIO_RWIMSC);
+                writel(chip->fwimsc, chip->addr + NMK_GPIO_FWIMSC);
+
+                if (cpu_is_u8500v2())
+                        writel(chip->slpm, chip->addr + NMK_GPIO_SLPC);
+        }
+}
+
+static int __devinit nmk_gpio_probe(struct platform_device *dev)
+{
+        struct nmk_gpio_platform_data *pdata = dev->dev.platform_data;
+        struct nmk_gpio_chip *nmk_chip;
+        struct gpio_chip *chip;
+        struct resource *res;
+        struct clk *clk;
+        int secondary_irq;
+        int irq;
+        int ret;
+
+        if (!pdata)
+                return -ENODEV;
+
+        res = platform_get_resource(dev, IORESOURCE_MEM, 0);
+        if (!res) {
+                ret = -ENOENT;
+                goto out;
+        }
+
+        irq = platform_get_irq(dev, 0);
+        if (irq < 0) {
+                ret = irq;
+                goto out;
+        }
+
+        secondary_irq = platform_get_irq(dev, 1);
+        if (secondary_irq >= 0 && !pdata->get_secondary_status) {
+                ret = -EINVAL;
+                goto out;
+        }
+
+        if (request_mem_region(res->start, resource_size(res),
+                               dev_name(&dev->dev)) == NULL) {
+                ret = -EBUSY;
+                goto out;
+        }
+
+        clk = clk_get(&dev->dev, NULL);
+        if (IS_ERR(clk)) {
+                ret = PTR_ERR(clk);
+                goto out_release;
+        }
+
+        clk_enable(clk);
+
+        nmk_chip = kzalloc(sizeof(*nmk_chip), GFP_KERNEL);
+        if (!nmk_chip) {
+                ret = -ENOMEM;
+                goto out_clk;
+        }
+        /*
+         * The virt address in nmk_chip->addr is in the nomadik register space,
+         * so we can simply convert the resource address, without remapping
+         */
+        nmk_chip->bank = dev->id;
+        nmk_chip->clk = clk;
+        nmk_chip->addr = io_p2v(res->start);
+        nmk_chip->chip = nmk_gpio_template;
+        nmk_chip->parent_irq = irq;
+        nmk_chip->secondary_parent_irq = secondary_irq;
+        nmk_chip->get_secondary_status = pdata->get_secondary_status;
+        nmk_chip->set_ioforce = pdata->set_ioforce;
+        spin_lock_init(&nmk_chip->lock);
+
+        chip = &nmk_chip->chip;
+        chip->base = pdata->first_gpio;
+        chip->ngpio = pdata->num_gpio;
+        chip->label = pdata->name ?: dev_name(&dev->dev);
+        chip->dev = &dev->dev;
+        chip->owner = THIS_MODULE;
+
+        ret = gpiochip_add(&nmk_chip->chip);
+        if (ret)
+                goto out_free;
+
+        BUG_ON(nmk_chip->bank >= ARRAY_SIZE(nmk_gpio_chips));
+
+        nmk_gpio_chips[nmk_chip->bank] = nmk_chip;
+        platform_set_drvdata(dev, nmk_chip);
+
+        nmk_gpio_init_irq(nmk_chip);
+
+        dev_info(&dev->dev, "Bits %i-%i at address %p\n",
+                 nmk_chip->chip.base, nmk_chip->chip.base+31, nmk_chip->addr);
+        return 0;
+
+out_free:
+        kfree(nmk_chip);
+out_clk:
+        clk_disable(clk);
+        clk_put(clk);
+out_release:
+        release_mem_region(res->start, resource_size(res));
+out:
+        dev_err(&dev->dev, "Failure %i for GPIO %i-%i\n", ret,
+                  pdata->first_gpio, pdata->first_gpio+31);
+        return ret;
+}
+
+static struct platform_driver nmk_gpio_driver = {
+        .driver = {
+                .owner = THIS_MODULE,
+                .name = "gpio",
+        },
+        .probe = nmk_gpio_probe,
+};
+
+static int __init nmk_gpio_init(void)
+{
+        return platform_driver_register(&nmk_gpio_driver);
+}
+
+core_initcall(nmk_gpio_init);
+
+MODULE_AUTHOR("Prafulla WADASKAR and Alessandro Rubini");
+MODULE_DESCRIPTION("Nomadik GPIO Driver");
+MODULE_LICENSE("GPL");
+
+