5 files changed, 915 insertions, 1 deletions

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 4fd0f276df5a..724038dab4ca 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -195,6 +195,13 @@ config GPIO_PCF857X
           This driver provides an in-kernel interface to those GPIOs using
           platform-neutral GPIO calls.
 
+config GPIO_TC35892
+        bool "TC35892 GPIOs"
+        depends on MFD_TC35892
+        help
+          This enables support for the GPIOs found on the TC35892
+          I/O Expander.
+
 config GPIO_TWL4030
         tristate "TWL4030, TWL5030, and TPS659x0 GPIOs"
         depends on TWL4030_CORE
@@ -282,6 +289,15 @@ config GPIO_TIMBERDALE
         ---help---
         Add support for the GPIO IP in the timberdale FPGA.
 
+config GPIO_RDC321X
+        tristate "RDC R-321x GPIO support"
+        depends on PCI && GPIOLIB
+        select MFD_CORE
+        select MFD_RDC321X
+        help
+          Support for the RDC R321x SoC GPIOs over southbridge
+          PCI configuration space.
+
 comment "SPI GPIO expanders:"
 
 config GPIO_MAX7301
@@ -317,4 +333,14 @@ config GPIO_UCB1400
           To compile this driver as a module, choose M here: the
           module will be called ucb1400_gpio.
 
+comment "MODULbus GPIO expanders:"
+
+config GPIO_JANZ_TTL
+        tristate "Janz VMOD-TTL Digital IO Module"
+        depends on MFD_JANZ_CMODIO
+        help
+          This enables support for the Janz VMOD-TTL Digital IO module.
+          This driver provides support for driving the pins in output
+          mode only. Input mode is not supported.
+
 endif
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 10f3f8d958b1..51c3cdd41b5a 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_GPIO_MCP23S08)	+= mcp23s08.o
 obj-$(CONFIG_GPIO_PCA953X)      += pca953x.o
 obj-$(CONFIG_GPIO_PCF857X)      += pcf857x.o
 obj-$(CONFIG_GPIO_PL061)        += pl061.o
+obj-$(CONFIG_GPIO_TC35892)      += tc35892-gpio.o
 obj-$(CONFIG_GPIO_TIMBERDALE)   += timbgpio.o
 obj-$(CONFIG_GPIO_TWL4030)      += twl4030-gpio.o
 obj-$(CONFIG_GPIO_UCB1400)      += ucb1400_gpio.o
@@ -27,4 +28,6 @@ obj-$(CONFIG_GPIO_VR41XX)	+= vr41xx_giu.o
 obj-$(CONFIG_GPIO_WM831X)       += wm831x-gpio.o
 obj-$(CONFIG_GPIO_WM8350)       += wm8350-gpiolib.o
 obj-$(CONFIG_GPIO_WM8994)       += wm8994-gpio.o
-obj-$(CONFIG_GPIO_SCH)          += sch_gpio.o
\ No newline at end of file
+obj-$(CONFIG_GPIO_SCH)          += sch_gpio.o
+obj-$(CONFIG_GPIO_RDC321X)      += rdc321x-gpio.o
+obj-$(CONFIG_GPIO_JANZ_TTL)     += janz-ttl.o
diff --git a/drivers/gpio/janz-ttl.c b/drivers/gpio/janz-ttl.c
new file mode 100644
index 000000000000..813ac077e5d7
--- /dev/null
+++ b/drivers/gpio/janz-ttl.c
@@ -0,0 +1,258 @@
+/*
+ * Janz MODULbus VMOD-TTL GPIO Driver
+ *
+ * Copyright (c) 2010 Ira W. Snyder <iws@ovro.caltech.edu>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+#include <linux/slab.h>
+
+#include <linux/mfd/janz.h>
+
+#define DRV_NAME "janz-ttl"
+
+#define PORTA_DIRECTION         0x23
+#define PORTB_DIRECTION         0x2B
+#define PORTC_DIRECTION         0x06
+#define PORTA_IOCTL             0x24
+#define PORTB_IOCTL             0x2C
+#define PORTC_IOCTL             0x07
+
+#define MASTER_INT_CTL          0x00
+#define MASTER_CONF_CTL         0x01
+
+#define CONF_PAE                (1 << 2)
+#define CONF_PBE                (1 << 7)
+#define CONF_PCE                (1 << 4)
+
+struct ttl_control_regs {
+        __be16 portc;
+        __be16 portb;
+        __be16 porta;
+        __be16 control;
+};
+
+struct ttl_module {
+        struct gpio_chip gpio;
+
+        /* base address of registers */
+        struct ttl_control_regs __iomem *regs;
+
+        u8 portc_shadow;
+        u8 portb_shadow;
+        u8 porta_shadow;
+
+        spinlock_t lock;
+};
+
+static int ttl_get_value(struct gpio_chip *gpio, unsigned offset)
+{
+        struct ttl_module *mod = dev_get_drvdata(gpio->dev);
+        u8 *shadow;
+        int ret;
+
+        if (offset < 8) {
+                shadow = &mod->porta_shadow;
+        } else if (offset < 16) {
+                shadow = &mod->portb_shadow;
+                offset -= 8;
+        } else {
+                shadow = &mod->portc_shadow;
+                offset -= 16;
+        }
+
+        spin_lock(&mod->lock);
+        ret = *shadow & (1 << offset);
+        spin_unlock(&mod->lock);
+        return ret;
+}
+
+static void ttl_set_value(struct gpio_chip *gpio, unsigned offset, int value)
+{
+        struct ttl_module *mod = dev_get_drvdata(gpio->dev);
+        void __iomem *port;
+        u8 *shadow;
+
+        if (offset < 8) {
+                port = &mod->regs->porta;
+                shadow = &mod->porta_shadow;
+        } else if (offset < 16) {
+                port = &mod->regs->portb;
+                shadow = &mod->portb_shadow;
+                offset -= 8;
+        } else {
+                port = &mod->regs->portc;
+                shadow = &mod->portc_shadow;
+                offset -= 16;
+        }
+
+        spin_lock(&mod->lock);
+        if (value)
+                *shadow |= (1 << offset);
+        else
+                *shadow &= ~(1 << offset);
+
+        iowrite16be(*shadow, port);
+        spin_unlock(&mod->lock);
+}
+
+static void __devinit ttl_write_reg(struct ttl_module *mod, u8 reg, u16 val)
+{
+        iowrite16be(reg, &mod->regs->control);
+        iowrite16be(val, &mod->regs->control);
+}
+
+static void __devinit ttl_setup_device(struct ttl_module *mod)
+{
+        /* reset the device to a known state */
+        iowrite16be(0x0000, &mod->regs->control);
+        iowrite16be(0x0001, &mod->regs->control);
+        iowrite16be(0x0000, &mod->regs->control);
+
+        /* put all ports in open-drain mode */
+        ttl_write_reg(mod, PORTA_IOCTL, 0x00ff);
+        ttl_write_reg(mod, PORTB_IOCTL, 0x00ff);
+        ttl_write_reg(mod, PORTC_IOCTL, 0x000f);
+
+        /* set all ports as outputs */
+        ttl_write_reg(mod, PORTA_DIRECTION, 0x0000);
+        ttl_write_reg(mod, PORTB_DIRECTION, 0x0000);
+        ttl_write_reg(mod, PORTC_DIRECTION, 0x0000);
+
+        /* set all ports to drive zeroes */
+        iowrite16be(0x0000, &mod->regs->porta);
+        iowrite16be(0x0000, &mod->regs->portb);
+        iowrite16be(0x0000, &mod->regs->portc);
+
+        /* enable all ports */
+        ttl_write_reg(mod, MASTER_CONF_CTL, CONF_PAE | CONF_PBE | CONF_PCE);
+}
+
+static int __devinit ttl_probe(struct platform_device *pdev)
+{
+        struct janz_platform_data *pdata;
+        struct device *dev = &pdev->dev;
+        struct ttl_module *mod;
+        struct gpio_chip *gpio;
+        struct resource *res;
+        int ret;
+
+        pdata = pdev->dev.platform_data;
+        if (!pdata) {
+                dev_err(dev, "no platform data\n");
+                ret = -ENXIO;
+                goto out_return;
+        }
+
+        mod = kzalloc(sizeof(*mod), GFP_KERNEL);
+        if (!mod) {
+                dev_err(dev, "unable to allocate private data\n");
+                ret = -ENOMEM;
+                goto out_return;
+        }
+
+        platform_set_drvdata(pdev, mod);
+        spin_lock_init(&mod->lock);
+
+        /* get access to the MODULbus registers for this module */
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!res) {
+                dev_err(dev, "MODULbus registers not found\n");
+                ret = -ENODEV;
+                goto out_free_mod;
+        }
+
+        mod->regs = ioremap(res->start, resource_size(res));
+        if (!mod->regs) {
+                dev_err(dev, "MODULbus registers not ioremap\n");
+                ret = -ENOMEM;
+                goto out_free_mod;
+        }
+
+        ttl_setup_device(mod);
+
+        /* Initialize the GPIO data structures */
+        gpio = &mod->gpio;
+        gpio->dev = &pdev->dev;
+        gpio->label = pdev->name;
+        gpio->get = ttl_get_value;
+        gpio->set = ttl_set_value;
+        gpio->owner = THIS_MODULE;
+
+        /* request dynamic allocation */
+        gpio->base = -1;
+        gpio->ngpio = 20;
+
+        ret = gpiochip_add(gpio);
+        if (ret) {
+                dev_err(dev, "unable to add GPIO chip\n");
+                goto out_iounmap_regs;
+        }
+
+        dev_info(&pdev->dev, "module %d: registered GPIO device\n",
+                             pdata->modno);
+        return 0;
+
+out_iounmap_regs:
+        iounmap(mod->regs);
+out_free_mod:
+        kfree(mod);
+out_return:
+        return ret;
+}
+
+static int __devexit ttl_remove(struct platform_device *pdev)
+{
+        struct ttl_module *mod = platform_get_drvdata(pdev);
+        struct device *dev = &pdev->dev;
+        int ret;
+
+        ret = gpiochip_remove(&mod->gpio);
+        if (ret) {
+                dev_err(dev, "unable to remove GPIO chip\n");
+                return ret;
+        }
+
+        iounmap(mod->regs);
+        kfree(mod);
+        return 0;
+}
+
+static struct platform_driver ttl_driver = {
+        .driver         = {
+                .name   = DRV_NAME,
+                .owner  = THIS_MODULE,
+        },
+        .probe          = ttl_probe,
+        .remove         = __devexit_p(ttl_remove),
+};
+
+static int __init ttl_init(void)
+{
+        return platform_driver_register(&ttl_driver);
+}
+
+static void __exit ttl_exit(void)
+{
+        platform_driver_unregister(&ttl_driver);
+}
+
+MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>");
+MODULE_DESCRIPTION("Janz MODULbus VMOD-TTL Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:janz-ttl");
+
+module_init(ttl_init);
+module_exit(ttl_exit);
diff --git a/drivers/gpio/rdc321x-gpio.c b/drivers/gpio/rdc321x-gpio.c
new file mode 100644
index 000000000000..2762698e0204
--- /dev/null
+++ b/drivers/gpio/rdc321x-gpio.c
@@ -0,0 +1,246 @@
+/*
+ * RDC321x GPIO driver
+ *
+ * Copyright (C) 2008, Volker Weiss <dev@tintuc.de>
+ * Copyright (C) 2007-2010 Florian Fainelli <florian@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/platform_device.h>
+#include <linux/pci.h>
+#include <linux/gpio.h>
+#include <linux/mfd/rdc321x.h>
+#include <linux/slab.h>
+
+struct rdc321x_gpio {
+        spinlock_t              lock;
+        struct pci_dev          *sb_pdev;
+        u32                     data_reg[2];
+        int                     reg1_ctrl_base;
+        int                     reg1_data_base;
+        int                     reg2_ctrl_base;
+        int                     reg2_data_base;
+        struct gpio_chip        chip;
+};
+
+/* read GPIO pin */
+static int rdc_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
+{
+        struct rdc321x_gpio *gpch;
+        u32 value = 0;
+        int reg;
+
+        gpch = container_of(chip, struct rdc321x_gpio, chip);
+        reg = gpio < 32 ? gpch->reg1_data_base : gpch->reg2_data_base;
+
+        spin_lock(&gpch->lock);
+        pci_write_config_dword(gpch->sb_pdev, reg,
+                                        gpch->data_reg[gpio < 32 ? 0 : 1]);
+        pci_read_config_dword(gpch->sb_pdev, reg, &value);
+        spin_unlock(&gpch->lock);
+
+        return (1 << (gpio & 0x1f)) & value ? 1 : 0;
+}
+
+static void rdc_gpio_set_value_impl(struct gpio_chip *chip,
+                                unsigned gpio, int value)
+{
+        struct rdc321x_gpio *gpch;
+        int reg = (gpio < 32) ? 0 : 1;
+
+        gpch = container_of(chip, struct rdc321x_gpio, chip);
+
+        if (value)
+                gpch->data_reg[reg] |= 1 << (gpio & 0x1f);
+        else
+                gpch->data_reg[reg] &= ~(1 << (gpio & 0x1f));
+
+        pci_write_config_dword(gpch->sb_pdev,
+                        reg ? gpch->reg2_data_base : gpch->reg1_data_base,
+                        gpch->data_reg[reg]);
+}
+
+/* set GPIO pin to value */
+static void rdc_gpio_set_value(struct gpio_chip *chip,
+                                unsigned gpio, int value)
+{
+        struct rdc321x_gpio *gpch;
+
+        gpch = container_of(chip, struct rdc321x_gpio, chip);
+        spin_lock(&gpch->lock);
+        rdc_gpio_set_value_impl(chip, gpio, value);
+        spin_unlock(&gpch->lock);
+}
+
+static int rdc_gpio_config(struct gpio_chip *chip,
+                                unsigned gpio, int value)
+{
+        struct rdc321x_gpio *gpch;
+        int err;
+        u32 reg;
+
+        gpch = container_of(chip, struct rdc321x_gpio, chip);
+
+        spin_lock(&gpch->lock);
+        err = pci_read_config_dword(gpch->sb_pdev, gpio < 32 ?
+                        gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, &reg);
+        if (err)
+                goto unlock;
+
+        reg |= 1 << (gpio & 0x1f);
+
+        err = pci_write_config_dword(gpch->sb_pdev, gpio < 32 ?
+                        gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, reg);
+        if (err)
+                goto unlock;
+
+        rdc_gpio_set_value_impl(chip, gpio, value);
+
+unlock:
+        spin_unlock(&gpch->lock);
+
+        return err;
+}
+
+/* configure GPIO pin as input */
+static int rdc_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
+{
+        return rdc_gpio_config(chip, gpio, 1);
+}
+
+/*
+ * Cache the initial value of both GPIO data registers
+ */
+static int __devinit rdc321x_gpio_probe(struct platform_device *pdev)
+{
+        int err;
+        struct resource *r;
+        struct rdc321x_gpio *rdc321x_gpio_dev;
+        struct rdc321x_gpio_pdata *pdata;
+
+        pdata = pdev->dev.platform_data;
+        if (!pdata) {
+                dev_err(&pdev->dev, "no platform data supplied\n");
+                return -ENODEV;
+        }
+
+        rdc321x_gpio_dev = kzalloc(sizeof(struct rdc321x_gpio), GFP_KERNEL);
+        if (!rdc321x_gpio_dev) {
+                dev_err(&pdev->dev, "failed to allocate private data\n");
+                return -ENOMEM;
+        }
+
+        r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg1");
+        if (!r) {
+                dev_err(&pdev->dev, "failed to get gpio-reg1 resource\n");
+                err = -ENODEV;
+                goto out_free;
+        }
+
+        spin_lock_init(&rdc321x_gpio_dev->lock);
+        rdc321x_gpio_dev->sb_pdev = pdata->sb_pdev;
+        rdc321x_gpio_dev->reg1_ctrl_base = r->start;
+        rdc321x_gpio_dev->reg1_data_base = r->start + 0x4;
+
+        r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg2");
+        if (!r) {
+                dev_err(&pdev->dev, "failed to get gpio-reg2 resource\n");
+                err = -ENODEV;
+                goto out_free;
+        }
+
+        rdc321x_gpio_dev->reg2_ctrl_base = r->start;
+        rdc321x_gpio_dev->reg2_data_base = r->start + 0x4;
+
+        rdc321x_gpio_dev->chip.label = "rdc321x-gpio";
+        rdc321x_gpio_dev->chip.direction_input = rdc_gpio_direction_input;
+        rdc321x_gpio_dev->chip.direction_output = rdc_gpio_config;
+        rdc321x_gpio_dev->chip.get = rdc_gpio_get_value;
+        rdc321x_gpio_dev->chip.set = rdc_gpio_set_value;
+        rdc321x_gpio_dev->chip.base = 0;
+        rdc321x_gpio_dev->chip.ngpio = pdata->max_gpios;
+
+        platform_set_drvdata(pdev, rdc321x_gpio_dev);
+
+        /* This might not be, what others (BIOS, bootloader, etc.)
+           wrote to these registers before, but it's a good guess. Still
+           better than just using 0xffffffff. */
+        err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev,
+                                        rdc321x_gpio_dev->reg1_data_base,
+                                        &rdc321x_gpio_dev->data_reg[0]);
+        if (err)
+                goto out_drvdata;
+
+        err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev,
+                                        rdc321x_gpio_dev->reg2_data_base,
+                                        &rdc321x_gpio_dev->data_reg[1]);
+        if (err)
+                goto out_drvdata;
+
+        dev_info(&pdev->dev, "registering %d GPIOs\n",
+                                        rdc321x_gpio_dev->chip.ngpio);
+        return gpiochip_add(&rdc321x_gpio_dev->chip);
+
+out_drvdata:
+        platform_set_drvdata(pdev, NULL);
+out_free:
+        kfree(rdc321x_gpio_dev);
+        return err;
+}
+
+static int __devexit rdc321x_gpio_remove(struct platform_device *pdev)
+{
+        int ret;
+        struct rdc321x_gpio *rdc321x_gpio_dev = platform_get_drvdata(pdev);
+
+        ret = gpiochip_remove(&rdc321x_gpio_dev->chip);
+        if (ret)
+                dev_err(&pdev->dev, "failed to unregister chip\n");
+
+        kfree(rdc321x_gpio_dev);
+        platform_set_drvdata(pdev, NULL);
+
+        return ret;
+}
+
+static struct platform_driver rdc321x_gpio_driver = {
+        .driver.name    = "rdc321x-gpio",
+        .driver.owner   = THIS_MODULE,
+        .probe          = rdc321x_gpio_probe,
+        .remove         = __devexit_p(rdc321x_gpio_remove),
+};
+
+static int __init rdc321x_gpio_init(void)
+{
+        return platform_driver_register(&rdc321x_gpio_driver);
+}
+
+static void __exit rdc321x_gpio_exit(void)
+{
+        platform_driver_unregister(&rdc321x_gpio_driver);
+}
+
+module_init(rdc321x_gpio_init);
+module_exit(rdc321x_gpio_exit);
+
+MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
+MODULE_DESCRIPTION("RDC321x GPIO driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:rdc321x-gpio");
diff --git a/drivers/gpio/tc35892-gpio.c b/drivers/gpio/tc35892-gpio.c
new file mode 100644
index 000000000000..1be6288780de
--- /dev/null
+++ b/drivers/gpio/tc35892-gpio.c
@@ -0,0 +1,381 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010
+ *
+ * License Terms: GNU General Public License, version 2
+ * Author: Hanumath Prasad <hanumath.prasad@stericsson.com> for ST-Ericsson
+ * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/gpio.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/tc35892.h>
+
+/*
+ * These registers are modified under the irq bus lock and cached to avoid
+ * unnecessary writes in bus_sync_unlock.
+ */
+enum { REG_IBE, REG_IEV, REG_IS, REG_IE };
+
+#define CACHE_NR_REGS   4
+#define CACHE_NR_BANKS  3
+
+struct tc35892_gpio {
+        struct gpio_chip chip;
+        struct tc35892 *tc35892;
+        struct device *dev;
+        struct mutex irq_lock;
+
+        int irq_base;
+
+        /* Caches of interrupt control registers for bus_lock */
+        u8 regs[CACHE_NR_REGS][CACHE_NR_BANKS];
+        u8 oldregs[CACHE_NR_REGS][CACHE_NR_BANKS];
+};
+
+static inline struct tc35892_gpio *to_tc35892_gpio(struct gpio_chip *chip)
+{
+        return container_of(chip, struct tc35892_gpio, chip);
+}
+
+static int tc35892_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+        struct tc35892_gpio *tc35892_gpio = to_tc35892_gpio(chip);
+        struct tc35892 *tc35892 = tc35892_gpio->tc35892;
+        u8 reg = TC35892_GPIODATA0 + (offset / 8) * 2;
+        u8 mask = 1 << (offset % 8);
+        int ret;
+
+        ret = tc35892_reg_read(tc35892, reg);
+        if (ret < 0)
+                return ret;
+
+        return ret & mask;
+}
+
+static void tc35892_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
+{
+        struct tc35892_gpio *tc35892_gpio = to_tc35892_gpio(chip);
+        struct tc35892 *tc35892 = tc35892_gpio->tc35892;
+        u8 reg = TC35892_GPIODATA0 + (offset / 8) * 2;
+        unsigned pos = offset % 8;
+        u8 data[] = {!!val << pos, 1 << pos};
+
+        tc35892_block_write(tc35892, reg, ARRAY_SIZE(data), data);
+}
+
+static int tc35892_gpio_direction_output(struct gpio_chip *chip,
+                                         unsigned offset, int val)
+{
+        struct tc35892_gpio *tc35892_gpio = to_tc35892_gpio(chip);
+        struct tc35892 *tc35892 = tc35892_gpio->tc35892;
+        u8 reg = TC35892_GPIODIR0 + offset / 8;
+        unsigned pos = offset % 8;
+
+        tc35892_gpio_set(chip, offset, val);
+
+        return tc35892_set_bits(tc35892, reg, 1 << pos, 1 << pos);
+}
+
+static int tc35892_gpio_direction_input(struct gpio_chip *chip,
+                                        unsigned offset)
+{
+        struct tc35892_gpio *tc35892_gpio = to_tc35892_gpio(chip);
+        struct tc35892 *tc35892 = tc35892_gpio->tc35892;
+        u8 reg = TC35892_GPIODIR0 + offset / 8;
+        unsigned pos = offset % 8;
+
+        return tc35892_set_bits(tc35892, reg, 1 << pos, 0);
+}
+
+static int tc35892_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+        struct tc35892_gpio *tc35892_gpio = to_tc35892_gpio(chip);
+
+        return tc35892_gpio->irq_base + offset;
+}
+
+static struct gpio_chip template_chip = {
+        .label                  = "tc35892",
+        .owner                  = THIS_MODULE,
+        .direction_input        = tc35892_gpio_direction_input,
+        .get                    = tc35892_gpio_get,
+        .direction_output       = tc35892_gpio_direction_output,
+        .set                    = tc35892_gpio_set,
+        .to_irq                 = tc35892_gpio_to_irq,
+        .can_sleep              = 1,
+};
+
+static int tc35892_gpio_irq_set_type(unsigned int irq, unsigned int type)
+{
+        struct tc35892_gpio *tc35892_gpio = get_irq_chip_data(irq);
+        int offset = irq - tc35892_gpio->irq_base;
+        int regoffset = offset / 8;
+        int mask = 1 << (offset % 8);
+
+        if (type == IRQ_TYPE_EDGE_BOTH) {
+                tc35892_gpio->regs[REG_IBE][regoffset] |= mask;
+                return 0;
+        }
+
+        tc35892_gpio->regs[REG_IBE][regoffset] &= ~mask;
+
+        if (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_LEVEL_HIGH)
+                tc35892_gpio->regs[REG_IS][regoffset] |= mask;
+        else
+                tc35892_gpio->regs[REG_IS][regoffset] &= ~mask;
+
+        if (type == IRQ_TYPE_EDGE_RISING || type == IRQ_TYPE_LEVEL_HIGH)
+                tc35892_gpio->regs[REG_IEV][regoffset] |= mask;
+        else
+                tc35892_gpio->regs[REG_IEV][regoffset] &= ~mask;
+
+        return 0;
+}
+
+static void tc35892_gpio_irq_lock(unsigned int irq)
+{
+        struct tc35892_gpio *tc35892_gpio = get_irq_chip_data(irq);
+
+        mutex_lock(&tc35892_gpio->irq_lock);
+}
+
+static void tc35892_gpio_irq_sync_unlock(unsigned int irq)
+{
+        struct tc35892_gpio *tc35892_gpio = get_irq_chip_data(irq);
+        struct tc35892 *tc35892 = tc35892_gpio->tc35892;
+        static const u8 regmap[] = {
+                [REG_IBE]       = TC35892_GPIOIBE0,
+                [REG_IEV]       = TC35892_GPIOIEV0,
+                [REG_IS]        = TC35892_GPIOIS0,
+                [REG_IE]        = TC35892_GPIOIE0,
+        };
+        int i, j;
+
+        for (i = 0; i < CACHE_NR_REGS; i++) {
+                for (j = 0; j < CACHE_NR_BANKS; j++) {
+                        u8 old = tc35892_gpio->oldregs[i][j];
+                        u8 new = tc35892_gpio->regs[i][j];
+
+                        if (new == old)
+                                continue;
+
+                        tc35892_gpio->oldregs[i][j] = new;
+                        tc35892_reg_write(tc35892, regmap[i] + j * 8, new);
+                }
+        }
+
+        mutex_unlock(&tc35892_gpio->irq_lock);
+}
+
+static void tc35892_gpio_irq_mask(unsigned int irq)
+{
+        struct tc35892_gpio *tc35892_gpio = get_irq_chip_data(irq);
+        int offset = irq - tc35892_gpio->irq_base;
+        int regoffset = offset / 8;
+        int mask = 1 << (offset % 8);
+
+        tc35892_gpio->regs[REG_IE][regoffset] &= ~mask;
+}
+
+static void tc35892_gpio_irq_unmask(unsigned int irq)
+{
+        struct tc35892_gpio *tc35892_gpio = get_irq_chip_data(irq);
+        int offset = irq - tc35892_gpio->irq_base;
+        int regoffset = offset / 8;
+        int mask = 1 << (offset % 8);
+
+        tc35892_gpio->regs[REG_IE][regoffset] |= mask;
+}
+
+static struct irq_chip tc35892_gpio_irq_chip = {
+        .name                   = "tc35892-gpio",
+        .bus_lock               = tc35892_gpio_irq_lock,
+        .bus_sync_unlock        = tc35892_gpio_irq_sync_unlock,
+        .mask                   = tc35892_gpio_irq_mask,
+        .unmask                 = tc35892_gpio_irq_unmask,
+        .set_type               = tc35892_gpio_irq_set_type,
+};
+
+static irqreturn_t tc35892_gpio_irq(int irq, void *dev)
+{
+        struct tc35892_gpio *tc35892_gpio = dev;
+        struct tc35892 *tc35892 = tc35892_gpio->tc35892;
+        u8 status[CACHE_NR_BANKS];
+        int ret;
+        int i;
+
+        ret = tc35892_block_read(tc35892, TC35892_GPIOMIS0,
+                                 ARRAY_SIZE(status), status);
+        if (ret < 0)
+                return IRQ_NONE;
+
+        for (i = 0; i < ARRAY_SIZE(status); i++) {
+                unsigned int stat = status[i];
+                if (!stat)
+                        continue;
+
+                while (stat) {
+                        int bit = __ffs(stat);
+                        int line = i * 8 + bit;
+
+                        handle_nested_irq(tc35892_gpio->irq_base + line);
+                        stat &= ~(1 << bit);
+                }
+
+                tc35892_reg_write(tc35892, TC35892_GPIOIC0 + i, status[i]);
+        }
+
+        return IRQ_HANDLED;
+}
+
+static int tc35892_gpio_irq_init(struct tc35892_gpio *tc35892_gpio)
+{
+        int base = tc35892_gpio->irq_base;
+        int irq;
+
+        for (irq = base; irq < base + tc35892_gpio->chip.ngpio; irq++) {
+                set_irq_chip_data(irq, tc35892_gpio);
+                set_irq_chip_and_handler(irq, &tc35892_gpio_irq_chip,
+                                         handle_simple_irq);
+                set_irq_nested_thread(irq, 1);
+#ifdef CONFIG_ARM
+                set_irq_flags(irq, IRQF_VALID);
+#else
+                set_irq_noprobe(irq);
+#endif
+        }
+
+        return 0;
+}
+
+static void tc35892_gpio_irq_remove(struct tc35892_gpio *tc35892_gpio)
+{
+        int base = tc35892_gpio->irq_base;
+        int irq;
+
+        for (irq = base; irq < base + tc35892_gpio->chip.ngpio; irq++) {
+#ifdef CONFIG_ARM
+                set_irq_flags(irq, 0);
+#endif
+                set_irq_chip_and_handler(irq, NULL, NULL);
+                set_irq_chip_data(irq, NULL);
+        }
+}
+
+static int __devinit tc35892_gpio_probe(struct platform_device *pdev)
+{
+        struct tc35892 *tc35892 = dev_get_drvdata(pdev->dev.parent);
+        struct tc35892_gpio_platform_data *pdata;
+        struct tc35892_gpio *tc35892_gpio;
+        int ret;
+        int irq;
+
+        pdata = tc35892->pdata->gpio;
+        if (!pdata)
+                return -ENODEV;
+
+        irq = platform_get_irq(pdev, 0);
+        if (irq < 0)
+                return irq;
+
+        tc35892_gpio = kzalloc(sizeof(struct tc35892_gpio), GFP_KERNEL);
+        if (!tc35892_gpio)
+                return -ENOMEM;
+
+        mutex_init(&tc35892_gpio->irq_lock);
+
+        tc35892_gpio->dev = &pdev->dev;
+        tc35892_gpio->tc35892 = tc35892;
+
+        tc35892_gpio->chip = template_chip;
+        tc35892_gpio->chip.ngpio = tc35892->num_gpio;
+        tc35892_gpio->chip.dev = &pdev->dev;
+        tc35892_gpio->chip.base = pdata->gpio_base;
+
+        tc35892_gpio->irq_base = tc35892->irq_base + TC35892_INT_GPIO(0);
+
+        /* Bring the GPIO module out of reset */
+        ret = tc35892_set_bits(tc35892, TC35892_RSTCTRL,
+                               TC35892_RSTCTRL_GPIRST, 0);
+        if (ret < 0)
+                goto out_free;
+
+        ret = tc35892_gpio_irq_init(tc35892_gpio);
+        if (ret)
+                goto out_free;
+
+        ret = request_threaded_irq(irq, NULL, tc35892_gpio_irq, IRQF_ONESHOT,
+                                   "tc35892-gpio", tc35892_gpio);
+        if (ret) {
+                dev_err(&pdev->dev, "unable to get irq: %d\n", ret);
+                goto out_removeirq;
+        }
+
+        ret = gpiochip_add(&tc35892_gpio->chip);
+        if (ret) {
+                dev_err(&pdev->dev, "unable to add gpiochip: %d\n", ret);
+                goto out_freeirq;
+        }
+
+        platform_set_drvdata(pdev, tc35892_gpio);
+
+        return 0;
+
+out_freeirq:
+        free_irq(irq, tc35892_gpio);
+out_removeirq:
+        tc35892_gpio_irq_remove(tc35892_gpio);
+out_free:
+        kfree(tc35892_gpio);
+        return ret;
+}
+
+static int __devexit tc35892_gpio_remove(struct platform_device *pdev)
+{
+        struct tc35892_gpio *tc35892_gpio = platform_get_drvdata(pdev);
+        int irq = platform_get_irq(pdev, 0);
+        int ret;
+
+        ret = gpiochip_remove(&tc35892_gpio->chip);
+        if (ret < 0) {
+                dev_err(tc35892_gpio->dev,
+                        "unable to remove gpiochip: %d\n", ret);
+                return ret;
+        }
+
+        free_irq(irq, tc35892_gpio);
+        tc35892_gpio_irq_remove(tc35892_gpio);
+
+        platform_set_drvdata(pdev, NULL);
+        kfree(tc35892_gpio);
+
+        return 0;
+}
+
+static struct platform_driver tc35892_gpio_driver = {
+        .driver.name    = "tc35892-gpio",
+        .driver.owner   = THIS_MODULE,
+        .probe          = tc35892_gpio_probe,
+        .remove         = __devexit_p(tc35892_gpio_remove),
+};
+
+static int __init tc35892_gpio_init(void)
+{
+        return platform_driver_register(&tc35892_gpio_driver);
+}
+subsys_initcall(tc35892_gpio_init);
+
+static void __exit tc35892_gpio_exit(void)
+{
+        platform_driver_unregister(&tc35892_gpio_driver);
+}
+module_exit(tc35892_gpio_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("TC35892 GPIO driver");
+MODULE_AUTHOR("Hanumath Prasad, Rabin Vincent");