--- /dev/null
+/*
+ * wm831x-gpio.c  --  gpiolib support for Wolfson WM831x PMICs
+ *
+ * Copyright 2009 Wolfson Microelectronics PLC.
+ *
+ * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+ *
+ *  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/gpio.h>
+#include <linux/mfd/core.h>
+#include <linux/platform_device.h>
+#include <linux/seq_file.h>
+
+#include <linux/mfd/wm831x/core.h>
+#include <linux/mfd/wm831x/pdata.h>
+#include <linux/mfd/wm831x/gpio.h>
+
+#define WM831X_GPIO_MAX 16
+
+struct wm831x_gpio {
+       struct wm831x *wm831x;
+       struct gpio_chip gpio_chip;
+};
+
+static inline struct wm831x_gpio *to_wm831x_gpio(struct gpio_chip *chip)
+{
+       return container_of(chip, struct wm831x_gpio, gpio_chip);
+}
+
+static int wm831x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
+{
+       struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
+       struct wm831x *wm831x = wm831x_gpio->wm831x;
+
+       return wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset,
+                              WM831X_GPN_DIR | WM831X_GPN_TRI,
+                              WM831X_GPN_DIR);
+}
+
+static int wm831x_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+       struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
+       struct wm831x *wm831x = wm831x_gpio->wm831x;
+       int ret;
+
+       ret = wm831x_reg_read(wm831x, WM831X_GPIO_LEVEL);
+       if (ret < 0)
+               return ret;
+
+       if (ret & 1 << offset)
+               return 1;
+       else
+               return 0;
+}
+
+static int wm831x_gpio_direction_out(struct gpio_chip *chip,
+                                    unsigned offset, int value)
+{
+       struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
+       struct wm831x *wm831x = wm831x_gpio->wm831x;
+
+       return wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset,
+                              WM831X_GPN_DIR | WM831X_GPN_TRI, 0);
+}
+
+static void wm831x_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+       struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
+       struct wm831x *wm831x = wm831x_gpio->wm831x;
+
+       wm831x_set_bits(wm831x, WM831X_GPIO_LEVEL, 1 << offset,
+                       value << offset);
+}
+
+#ifdef CONFIG_DEBUG_FS
+static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
+{
+       struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
+       struct wm831x *wm831x = wm831x_gpio->wm831x;
+       int i;
+
+       for (i = 0; i < chip->ngpio; i++) {
+               int gpio = i + chip->base;
+               int reg;
+               const char *label, *pull, *powerdomain;
+
+               /* We report the GPIO even if it's not requested since
+                * we're also reporting things like alternate
+                * functions which apply even when the GPIO is not in
+                * use as a GPIO.
+                */
+               label = gpiochip_is_requested(chip, i);
+               if (!label)
+                       label = "Unrequested";
+
+               seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);
+
+               reg = wm831x_reg_read(wm831x, WM831X_GPIO1_CONTROL + i);
+               if (reg < 0) {
+                       dev_err(wm831x->dev,
+                               "GPIO control %d read failed: %d\n",
+                               gpio, reg);
+                       seq_printf(s, "\n");
+                       continue;
+               }
+
+               switch (reg & WM831X_GPN_PULL_MASK) {
+               case WM831X_GPIO_PULL_NONE:
+                       pull = "nopull";
+                       break;
+               case WM831X_GPIO_PULL_DOWN:
+                       pull = "pulldown";
+                       break;
+               case WM831X_GPIO_PULL_UP:
+                       pull = "pullup";
+               default:
+                       pull = "INVALID PULL";
+                       break;
+               }
+
+               switch (i + 1) {
+               case 1 ... 3:
+               case 7 ... 9:
+                       if (reg & WM831X_GPN_PWR_DOM)
+                               powerdomain = "VPMIC";
+                       else
+                               powerdomain = "DBVDD";
+                       break;
+
+               case 4 ... 6:
+               case 10 ... 12:
+                       if (reg & WM831X_GPN_PWR_DOM)
+                               powerdomain = "SYSVDD";
+                       else
+                               powerdomain = "DBVDD";
+                       break;
+
+               case 13 ... 16:
+                       powerdomain = "TPVDD";
+                       break;
+
+               default:
+                       BUG();
+                       break;
+               }
+
+               seq_printf(s, " %s %s %s %s%s\n"
+                          "                                  %s%s (0x%4x)\n",
+                          reg & WM831X_GPN_DIR ? "in" : "out",
+                          wm831x_gpio_get(chip, i) ? "high" : "low",
+                          pull,
+                          powerdomain,
+                          reg & WM831X_GPN_POL ? " inverted" : "",
+                          reg & WM831X_GPN_OD ? "open-drain" : "CMOS",
+                          reg & WM831X_GPN_TRI ? " tristated" : "",
+                          reg);
+       }
+}
+#else
+#define wm831x_gpio_dbg_show NULL
+#endif
+
+static struct gpio_chip template_chip = {
+       .label                  = "wm831x",
+       .owner                  = THIS_MODULE,
+       .direction_input        = wm831x_gpio_direction_in,
+       .get                    = wm831x_gpio_get,
+       .direction_output       = wm831x_gpio_direction_out,
+       .set                    = wm831x_gpio_set,
+       .dbg_show               = wm831x_gpio_dbg_show,
+       .can_sleep              = 1,
+};
+
+static int __devinit wm831x_gpio_probe(struct platform_device *pdev)
+{
+       struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
+       struct wm831x_pdata *pdata = wm831x->dev->platform_data;
+       struct wm831x_gpio *wm831x_gpio;
+       int ret;
+
+       wm831x_gpio = kzalloc(sizeof(*wm831x_gpio), GFP_KERNEL);
+       if (wm831x_gpio == NULL)
+               return -ENOMEM;
+
+       wm831x_gpio->wm831x = wm831x;
+       wm831x_gpio->gpio_chip = template_chip;
+       wm831x_gpio->gpio_chip.ngpio = WM831X_GPIO_MAX;
+       wm831x_gpio->gpio_chip.dev = &pdev->dev;
+       if (pdata && pdata->gpio_base)
+               wm831x_gpio->gpio_chip.base = pdata->gpio_base;
+       else
+               wm831x_gpio->gpio_chip.base = -1;
+
+       ret = gpiochip_add(&wm831x_gpio->gpio_chip);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
+                       ret);
+               goto err;
+       }
+
+       platform_set_drvdata(pdev, wm831x_gpio);
+
+       return ret;
+
+err:
+       kfree(wm831x_gpio);
+       return ret;
+}
+
+static int __devexit wm831x_gpio_remove(struct platform_device *pdev)
+{
+       struct wm831x_gpio *wm831x_gpio = platform_get_drvdata(pdev);
+       int ret;
+
+       ret = gpiochip_remove(&wm831x_gpio->gpio_chip);
+       if (ret == 0)
+               kfree(wm831x_gpio);
+
+       return ret;
+}
+
+static struct platform_driver wm831x_gpio_driver = {
+       .driver.name    = "wm831x-gpio",
+       .driver.owner   = THIS_MODULE,
+       .probe          = wm831x_gpio_probe,
+       .remove         = __devexit_p(wm831x_gpio_remove),
+};
+
+static int __init wm831x_gpio_init(void)
+{
+       return platform_driver_register(&wm831x_gpio_driver);
+}
+subsys_initcall(wm831x_gpio_init);
+
+static void __exit wm831x_gpio_exit(void)
+{
+       platform_driver_unregister(&wm831x_gpio_driver);
+}
+module_exit(wm831x_gpio_exit);
+
+MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
+MODULE_DESCRIPTION("GPIO interface for WM831x PMICs");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:wm831x-gpio");
 
--- /dev/null
+/*
+ * include/linux/mfd/wm831x/gpio.h -- GPIO for WM831x
+ *
+ * Copyright 2009 Wolfson Microelectronics PLC.
+ *
+ * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+ *
+ *  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.
+ *
+ */
+
+#ifndef __MFD_WM831X_GPIO_H__
+#define __MFD_WM831X_GPIO_H__
+
+/*
+ * R16440-16455 (0x4038-0x4047) - GPIOx Control
+ */
+#define WM831X_GPN_DIR                          0x8000  /* GPN_DIR */
+#define WM831X_GPN_DIR_MASK                     0x8000  /* GPN_DIR */
+#define WM831X_GPN_DIR_SHIFT                        15  /* GPN_DIR */
+#define WM831X_GPN_DIR_WIDTH                         1  /* GPN_DIR */
+#define WM831X_GPN_PULL_MASK                    0x6000  /* GPN_PULL - [14:13] */
+#define WM831X_GPN_PULL_SHIFT                       13  /* GPN_PULL - [14:13] */
+#define WM831X_GPN_PULL_WIDTH                        2  /* GPN_PULL - [14:13] */
+#define WM831X_GPN_INT_MODE                     0x1000  /* GPN_INT_MODE */
+#define WM831X_GPN_INT_MODE_MASK                0x1000  /* GPN_INT_MODE */
+#define WM831X_GPN_INT_MODE_SHIFT                   12  /* GPN_INT_MODE */
+#define WM831X_GPN_INT_MODE_WIDTH                    1  /* GPN_INT_MODE */
+#define WM831X_GPN_PWR_DOM                      0x0800  /* GPN_PWR_DOM */
+#define WM831X_GPN_PWR_DOM_MASK                 0x0800  /* GPN_PWR_DOM */
+#define WM831X_GPN_PWR_DOM_SHIFT                    11  /* GPN_PWR_DOM */
+#define WM831X_GPN_PWR_DOM_WIDTH                     1  /* GPN_PWR_DOM */
+#define WM831X_GPN_POL                          0x0400  /* GPN_POL */
+#define WM831X_GPN_POL_MASK                     0x0400  /* GPN_POL */
+#define WM831X_GPN_POL_SHIFT                        10  /* GPN_POL */
+#define WM831X_GPN_POL_WIDTH                         1  /* GPN_POL */
+#define WM831X_GPN_OD                           0x0200  /* GPN_OD */
+#define WM831X_GPN_OD_MASK                      0x0200  /* GPN_OD */
+#define WM831X_GPN_OD_SHIFT                          9  /* GPN_OD */
+#define WM831X_GPN_OD_WIDTH                          1  /* GPN_OD */
+#define WM831X_GPN_TRI                          0x0080  /* GPN_TRI */
+#define WM831X_GPN_TRI_MASK                     0x0080  /* GPN_TRI */
+#define WM831X_GPN_TRI_SHIFT                         7  /* GPN_TRI */
+#define WM831X_GPN_TRI_WIDTH                         1  /* GPN_TRI */
+#define WM831X_GPN_FN_MASK                      0x000F  /* GPN_FN - [3:0] */
+#define WM831X_GPN_FN_SHIFT                          0  /* GPN_FN - [3:0] */
+#define WM831X_GPN_FN_WIDTH                          4  /* GPN_FN - [3:0] */
+
+#define WM831X_GPIO_PULL_NONE (0 << WM831X_GPN_PULL_SHIFT)
+#define WM831X_GPIO_PULL_DOWN (1 << WM831X_GPN_PULL_SHIFT)
+#define WM831X_GPIO_PULL_UP   (2 << WM831X_GPN_PULL_SHIFT)
+#endif