--- /dev/null
+/*
+ * wm97xx-core.c  --  Touch screen driver core for Wolfson WM9705, WM9712
+ *                    and WM9713 AC97 Codecs.
+ *
+ * Copyright 2003, 2004, 2005, 2006, 2007, 2008 Wolfson Microelectronics PLC.
+ * Author: Liam Girdwood
+ *         liam.girdwood@wolfsonmicro.com or linux@wolfsonmicro.com
+ * Parts Copyright : Ian Molton <spyro@f2s.com>
+ *                   Andrew Zabolotny <zap@homelink.ru>
+ *                   Russell King <rmk@arm.linux.org.uk>
+ *
+ *  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.
+ *
+ * Notes:
+ *
+ *  Features:
+ *       - supports WM9705, WM9712, WM9713
+ *       - polling mode
+ *       - continuous mode (arch-dependent)
+ *       - adjustable rpu/dpp settings
+ *       - adjustable pressure current
+ *       - adjustable sample settle delay
+ *       - 4 and 5 wire touchscreens (5 wire is WM9712 only)
+ *       - pen down detection
+ *       - battery monitor
+ *       - sample AUX adcs
+ *       - power management
+ *       - codec GPIO
+ *       - codec event notification
+ * Todo
+ *       - Support for async sampling control for noisy LCDs.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/string.h>
+#include <linux/proc_fs.h>
+#include <linux/pm.h>
+#include <linux/interrupt.h>
+#include <linux/bitops.h>
+#include <linux/workqueue.h>
+#include <linux/wm97xx.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+
+#define TS_NAME                        "wm97xx"
+#define WM_CORE_VERSION                "1.00"
+#define DEFAULT_PRESSURE       0xb0c0
+
+
+/*
+ * Touchscreen absolute values
+ *
+ * These parameters are used to help the input layer discard out of
+ * range readings and reduce jitter etc.
+ *
+ *   o min, max:- indicate the min and max values your touch screen returns
+ *   o fuzz:- use a higher number to reduce jitter
+ *
+ * The default values correspond to Mainstone II in QVGA mode
+ *
+ * Please read
+ * Documentation/input/input-programming.txt for more details.
+ */
+
+static int abs_x[3] = {350, 3900, 5};
+module_param_array(abs_x, int, NULL, 0);
+MODULE_PARM_DESC(abs_x, "Touchscreen absolute X min, max, fuzz");
+
+static int abs_y[3] = {320, 3750, 40};
+module_param_array(abs_y, int, NULL, 0);
+MODULE_PARM_DESC(abs_y, "Touchscreen absolute Y min, max, fuzz");
+
+static int abs_p[3] = {0, 150, 4};
+module_param_array(abs_p, int, NULL, 0);
+MODULE_PARM_DESC(abs_p, "Touchscreen absolute Pressure min, max, fuzz");
+
+/*
+ * wm97xx IO access, all IO locking done by AC97 layer
+ */
+int wm97xx_reg_read(struct wm97xx *wm, u16 reg)
+{
+       if (wm->ac97)
+               return wm->ac97->bus->ops->read(wm->ac97, reg);
+       else
+               return -1;
+}
+EXPORT_SYMBOL_GPL(wm97xx_reg_read);
+
+void wm97xx_reg_write(struct wm97xx *wm, u16 reg, u16 val)
+{
+       /* cache digitiser registers */
+       if (reg >= AC97_WM9713_DIG1 && reg <= AC97_WM9713_DIG3)
+               wm->dig[(reg - AC97_WM9713_DIG1) >> 1] = val;
+
+       /* cache gpio regs */
+       if (reg >= AC97_GPIO_CFG && reg <= AC97_MISC_AFE)
+               wm->gpio[(reg - AC97_GPIO_CFG) >> 1] = val;
+
+       /* wm9713 irq reg */
+       if (reg == 0x5a)
+               wm->misc = val;
+
+       if (wm->ac97)
+               wm->ac97->bus->ops->write(wm->ac97, reg, val);
+}
+EXPORT_SYMBOL_GPL(wm97xx_reg_write);
+
+/**
+ * wm97xx_read_aux_adc - Read the aux adc.
+ * @wm: wm97xx device.
+ * @adcsel: codec ADC to be read
+ *
+ * Reads the selected AUX ADC.
+ */
+
+int wm97xx_read_aux_adc(struct wm97xx *wm, u16 adcsel)
+{
+       int power_adc = 0, auxval;
+       u16 power = 0;
+
+       /* get codec */
+       mutex_lock(&wm->codec_mutex);
+
+       /* When the touchscreen is not in use, we may have to power up
+        * the AUX ADC before we can use sample the AUX inputs->
+        */
+       if (wm->id == WM9713_ID2 &&
+           (power = wm97xx_reg_read(wm, AC97_EXTENDED_MID)) & 0x8000) {
+               power_adc = 1;
+               wm97xx_reg_write(wm, AC97_EXTENDED_MID, power & 0x7fff);
+       }
+
+       /* Prepare the codec for AUX reading */
+       wm->codec->aux_prepare(wm);
+
+       /* Turn polling mode on to read AUX ADC */
+       wm->pen_probably_down = 1;
+       wm->codec->poll_sample(wm, adcsel, &auxval);
+
+       if (power_adc)
+               wm97xx_reg_write(wm, AC97_EXTENDED_MID, power | 0x8000);
+
+       wm->codec->dig_restore(wm);
+
+       wm->pen_probably_down = 0;
+
+       mutex_unlock(&wm->codec_mutex);
+       return auxval & 0xfff;
+}
+EXPORT_SYMBOL_GPL(wm97xx_read_aux_adc);
+
+/**
+ * wm97xx_get_gpio - Get the status of a codec GPIO.
+ * @wm: wm97xx device.
+ * @gpio: gpio
+ *
+ * Get the status of a codec GPIO pin
+ */
+
+enum wm97xx_gpio_status wm97xx_get_gpio(struct wm97xx *wm, u32 gpio)
+{
+       u16 status;
+       enum wm97xx_gpio_status ret;
+
+       mutex_lock(&wm->codec_mutex);
+       status = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
+
+       if (status & gpio)
+               ret = WM97XX_GPIO_HIGH;
+       else
+               ret = WM97XX_GPIO_LOW;
+
+       mutex_unlock(&wm->codec_mutex);
+       return ret;
+}
+EXPORT_SYMBOL_GPL(wm97xx_get_gpio);
+
+/**
+ * wm97xx_set_gpio - Set the status of a codec GPIO.
+ * @wm: wm97xx device.
+ * @gpio: gpio
+ *
+ *
+ * Set the status of a codec GPIO pin
+ */
+
+void wm97xx_set_gpio(struct wm97xx *wm, u32 gpio,
+                               enum wm97xx_gpio_status status)
+{
+       u16 reg;
+
+       mutex_lock(&wm->codec_mutex);
+       reg = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
+
+       if (status & WM97XX_GPIO_HIGH)
+               reg |= gpio;
+       else
+               reg &= ~gpio;
+
+       if (wm->id == WM9712_ID2)
+               wm97xx_reg_write(wm, AC97_GPIO_STATUS, reg << 1);
+       else
+               wm97xx_reg_write(wm, AC97_GPIO_STATUS, reg);
+       mutex_unlock(&wm->codec_mutex);
+}
+EXPORT_SYMBOL_GPL(wm97xx_set_gpio);
+
+/*
+ * Codec GPIO pin configuration, this sets pin direction, polarity,
+ * stickyness and wake up.
+ */
+void wm97xx_config_gpio(struct wm97xx *wm, u32 gpio, enum wm97xx_gpio_dir dir,
+                  enum wm97xx_gpio_pol pol, enum wm97xx_gpio_sticky sticky,
+                  enum wm97xx_gpio_wake wake)
+{
+       u16 reg;
+
+       mutex_lock(&wm->codec_mutex);
+       reg = wm97xx_reg_read(wm, AC97_GPIO_POLARITY);
+
+       if (pol == WM97XX_GPIO_POL_HIGH)
+               reg |= gpio;
+       else
+               reg &= ~gpio;
+
+       wm97xx_reg_write(wm, AC97_GPIO_POLARITY, reg);
+       reg = wm97xx_reg_read(wm, AC97_GPIO_STICKY);
+
+       if (sticky == WM97XX_GPIO_STICKY)
+               reg |= gpio;
+       else
+               reg &= ~gpio;
+
+       wm97xx_reg_write(wm, AC97_GPIO_STICKY, reg);
+       reg = wm97xx_reg_read(wm, AC97_GPIO_WAKEUP);
+
+       if (wake == WM97XX_GPIO_WAKE)
+               reg |= gpio;
+       else
+               reg &= ~gpio;
+
+       wm97xx_reg_write(wm, AC97_GPIO_WAKEUP, reg);
+       reg = wm97xx_reg_read(wm, AC97_GPIO_CFG);
+
+       if (dir == WM97XX_GPIO_IN)
+               reg |= gpio;
+       else
+               reg &= ~gpio;
+
+       wm97xx_reg_write(wm, AC97_GPIO_CFG, reg);
+       mutex_unlock(&wm->codec_mutex);
+}
+EXPORT_SYMBOL_GPL(wm97xx_config_gpio);
+
+/*
+ * Handle a pen down interrupt.
+ */
+static void wm97xx_pen_irq_worker(struct work_struct *work)
+{
+       struct wm97xx *wm = container_of(work, struct wm97xx, pen_event_work);
+       int pen_was_down = wm->pen_is_down;
+
+       /* do we need to enable the touch panel reader */
+       if (wm->id == WM9705_ID2) {
+               if (wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD) &
+                                       WM97XX_PEN_DOWN)
+                       wm->pen_is_down = 1;
+               else
+                       wm->pen_is_down = 0;
+       } else {
+               u16 status, pol;
+               mutex_lock(&wm->codec_mutex);
+               status = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
+               pol = wm97xx_reg_read(wm, AC97_GPIO_POLARITY);
+
+               if (WM97XX_GPIO_13 & pol & status) {
+                       wm->pen_is_down = 1;
+                       wm97xx_reg_write(wm, AC97_GPIO_POLARITY, pol &
+                                               ~WM97XX_GPIO_13);
+               } else {
+                       wm->pen_is_down = 0;
+                       wm97xx_reg_write(wm, AC97_GPIO_POLARITY, pol |
+                                        WM97XX_GPIO_13);
+               }
+
+               if (wm->id == WM9712_ID2)
+                       wm97xx_reg_write(wm, AC97_GPIO_STATUS, (status &
+                                               ~WM97XX_GPIO_13) << 1);
+               else
+                       wm97xx_reg_write(wm, AC97_GPIO_STATUS, status &
+                                               ~WM97XX_GPIO_13);
+               mutex_unlock(&wm->codec_mutex);
+       }
+
+       /* If the system is not using continuous mode or it provides a
+        * pen down operation then we need to schedule polls while the
+        * pen is down.  Otherwise the machine driver is responsible
+        * for scheduling reads.
+        */
+       if (!wm->mach_ops->acc_enabled || wm->mach_ops->acc_pen_down) {
+               if (wm->pen_is_down && !pen_was_down) {
+                       /* Data is not availiable immediately on pen down */
+                       queue_delayed_work(wm->ts_workq, &wm->ts_reader, 1);
+               }
+
+               /* Let ts_reader report the pen up for debounce. */
+               if (!wm->pen_is_down && pen_was_down)
+                       wm->pen_is_down = 1;
+       }
+
+       if (!wm->pen_is_down && wm->mach_ops->acc_enabled)
+               wm->mach_ops->acc_pen_up(wm);
+
+       wm->mach_ops->irq_enable(wm, 1);
+}
+
+/*
+ * Codec PENDOWN irq handler
+ *
+ * We have to disable the codec interrupt in the handler because it
+ * can take upto 1ms to clear the interrupt source. We schedule a task
+ * in a work queue to do the actual interaction with the chip (it
+ * doesn't matter if we end up reenqueing it before it is executed
+ * since we don't touch the chip until it has run).  The interrupt is
+ * then enabled again in the slow handler when the source has been
+ * cleared.
+ */
+static irqreturn_t wm97xx_pen_interrupt(int irq, void *dev_id)
+{
+       struct wm97xx *wm = dev_id;
+
+       wm->mach_ops->irq_enable(wm, 0);
+       queue_work(wm->ts_workq, &wm->pen_event_work);
+
+       return IRQ_HANDLED;
+}
+
+/*
+ * initialise pen IRQ handler and workqueue
+ */
+static int wm97xx_init_pen_irq(struct wm97xx *wm)
+{
+       u16 reg;
+
+       /* If an interrupt is supplied an IRQ enable operation must also be
+        * provided. */
+       BUG_ON(!wm->mach_ops->irq_enable);
+
+       if (request_irq(wm->pen_irq, wm97xx_pen_interrupt, IRQF_SHARED,
+                       "wm97xx-pen", wm)) {
+               dev_err(wm->dev,
+                       "Failed to register pen down interrupt, polling");
+               wm->pen_irq = 0;
+               return -EINVAL;
+       }
+
+       /* Configure GPIO as interrupt source on WM971x */
+       if (wm->id != WM9705_ID2) {
+               BUG_ON(!wm->mach_ops->irq_gpio);
+               reg = wm97xx_reg_read(wm, AC97_MISC_AFE);
+               wm97xx_reg_write(wm, AC97_MISC_AFE,
+                               reg & ~(wm->mach_ops->irq_gpio));
+               reg = wm97xx_reg_read(wm, 0x5a);
+               wm97xx_reg_write(wm, 0x5a, reg & ~0x0001);
+       }
+
+       return 0;
+}
+
+static int wm97xx_read_samples(struct wm97xx *wm)
+{
+       struct wm97xx_data data;
+       int rc;
+
+       mutex_lock(&wm->codec_mutex);
+
+       if (wm->mach_ops && wm->mach_ops->acc_enabled)
+               rc = wm->mach_ops->acc_pen_down(wm);
+       else
+               rc = wm->codec->poll_touch(wm, &data);
+
+       if (rc & RC_PENUP) {
+               if (wm->pen_is_down) {
+                       wm->pen_is_down = 0;
+                       dev_dbg(wm->dev, "pen up\n");
+                       input_report_abs(wm->input_dev, ABS_PRESSURE, 0);
+                       input_sync(wm->input_dev);
+               } else if (!(rc & RC_AGAIN)) {
+                       /* We need high frequency updates only while
+                       * pen is down, the user never will be able to
+                       * touch screen faster than a few times per
+                       * second... On the other hand, when the user
+                       * is actively working with the touchscreen we
+                       * don't want to lose the quick response. So we
+                       * will slowly increase sleep time after the
+                       * pen is up and quicky restore it to ~one task
+                       * switch when pen is down again.
+                       */
+                       if (wm->ts_reader_interval < HZ / 10)
+                               wm->ts_reader_interval++;
+               }
+
+       } else if (rc & RC_VALID) {
+               dev_dbg(wm->dev,
+                       "pen down: x=%x:%d, y=%x:%d, pressure=%x:%d\n",
+                       data.x >> 12, data.x & 0xfff, data.y >> 12,
+                       data.y & 0xfff, data.p >> 12, data.p & 0xfff);
+               input_report_abs(wm->input_dev, ABS_X, data.x & 0xfff);
+               input_report_abs(wm->input_dev, ABS_Y, data.y & 0xfff);
+               input_report_abs(wm->input_dev, ABS_PRESSURE, data.p & 0xfff);
+               input_sync(wm->input_dev);
+               wm->pen_is_down = 1;
+               wm->ts_reader_interval = wm->ts_reader_min_interval;
+       } else if (rc & RC_PENDOWN) {
+               dev_dbg(wm->dev, "pen down\n");
+               wm->pen_is_down = 1;
+               wm->ts_reader_interval = wm->ts_reader_min_interval;
+       }
+
+       mutex_unlock(&wm->codec_mutex);
+       return rc;
+}
+
+/*
+* The touchscreen sample reader.
+*/
+static void wm97xx_ts_reader(struct work_struct *work)
+{
+       int rc;
+       struct wm97xx *wm = container_of(work, struct wm97xx, ts_reader.work);
+
+       BUG_ON(!wm->codec);
+
+       do {
+               rc = wm97xx_read_samples(wm);
+       } while (rc & RC_AGAIN);
+
+       if (wm->pen_is_down || !wm->pen_irq)
+               queue_delayed_work(wm->ts_workq, &wm->ts_reader,
+                                  wm->ts_reader_interval);
+}
+
+/**
+ * wm97xx_ts_input_open - Open the touch screen input device.
+ * @idev:      Input device to be opened.
+ *
+ * Called by the input sub system to open a wm97xx touchscreen device.
+ * Starts the touchscreen thread and touch digitiser.
+ */
+static int wm97xx_ts_input_open(struct input_dev *idev)
+{
+       struct wm97xx *wm = input_get_drvdata(idev);
+
+       wm->ts_workq = create_singlethread_workqueue("kwm97xx");
+       if (wm->ts_workq == NULL) {
+               dev_err(wm->dev,
+                       "Failed to create workqueue\n");
+               return -EINVAL;
+       }
+
+       /* start digitiser */
+       if (wm->mach_ops && wm->mach_ops->acc_enabled)
+               wm->codec->acc_enable(wm, 1);
+       wm->codec->dig_enable(wm, 1);
+
+       INIT_DELAYED_WORK(&wm->ts_reader, wm97xx_ts_reader);
+       INIT_WORK(&wm->pen_event_work, wm97xx_pen_irq_worker);
+
+       wm->ts_reader_min_interval = HZ >= 100 ? HZ / 100 : 1;
+       if (wm->ts_reader_min_interval < 1)
+               wm->ts_reader_min_interval = 1;
+       wm->ts_reader_interval = wm->ts_reader_min_interval;
+
+       wm->pen_is_down = 0;
+       if (wm->pen_irq)
+               wm97xx_init_pen_irq(wm);
+       else
+               dev_err(wm->dev, "No IRQ specified\n");
+
+       /* If we either don't have an interrupt for pen down events or
+        * failed to acquire it then we need to poll.
+        */
+       if (wm->pen_irq == 0)
+               queue_delayed_work(wm->ts_workq, &wm->ts_reader,
+                                  wm->ts_reader_interval);
+
+       return 0;
+}
+
+/**
+ * wm97xx_ts_input_close - Close the touch screen input device.
+ * @idev:      Input device to be closed.
+ *
+ * Called by the input sub system to close a wm97xx touchscreen
+ * device.  Kills the touchscreen thread and stops the touch
+ * digitiser.
+ */
+
+static void wm97xx_ts_input_close(struct input_dev *idev)
+{
+       struct wm97xx *wm = input_get_drvdata(idev);
+       u16 reg;
+
+       if (wm->pen_irq) {
+               /* Return the interrupt to GPIO usage (disabling it) */
+               if (wm->id != WM9705_ID2) {
+                       BUG_ON(!wm->mach_ops->irq_gpio);
+                       reg = wm97xx_reg_read(wm, AC97_MISC_AFE);
+                       wm97xx_reg_write(wm, AC97_MISC_AFE,
+                                        reg | wm->mach_ops->irq_gpio);
+               }
+
+               free_irq(wm->pen_irq, wm);
+       }
+
+       wm->pen_is_down = 0;
+
+       /* Balance out interrupt disables/enables */
+       if (cancel_work_sync(&wm->pen_event_work))
+               wm->mach_ops->irq_enable(wm, 1);
+
+       /* ts_reader rearms itself so we need to explicitly stop it
+        * before we destroy the workqueue.
+        */
+       cancel_delayed_work_sync(&wm->ts_reader);
+
+       destroy_workqueue(wm->ts_workq);
+
+       /* stop digitiser */
+       wm->codec->dig_enable(wm, 0);
+       if (wm->mach_ops && wm->mach_ops->acc_enabled)
+               wm->codec->acc_enable(wm, 0);
+}
+
+static int wm97xx_probe(struct device *dev)
+{
+       struct wm97xx *wm;
+       int ret = 0, id = 0;
+
+       wm = kzalloc(sizeof(struct wm97xx), GFP_KERNEL);
+       if (!wm)
+               return -ENOMEM;
+       mutex_init(&wm->codec_mutex);
+
+       wm->dev = dev;
+       dev->driver_data = wm;
+       wm->ac97 = to_ac97_t(dev);
+
+       /* check that we have a supported codec */
+       id = wm97xx_reg_read(wm, AC97_VENDOR_ID1);
+       if (id != WM97XX_ID1) {
+               dev_err(dev, "Device with vendor %04x is not a wm97xx\n", id);
+               ret = -ENODEV;
+               goto alloc_err;
+       }
+
+       wm->id = wm97xx_reg_read(wm, AC97_VENDOR_ID2);
+
+       dev_info(wm->dev, "detected a wm97%02x codec\n", wm->id & 0xff);
+
+       switch (wm->id & 0xff) {
+#ifdef CONFIG_TOUCHSCREEN_WM9705
+       case 0x05:
+               wm->codec = &wm9705_codec;
+               break;
+#endif
+#ifdef CONFIG_TOUCHSCREEN_WM9712
+       case 0x12:
+               wm->codec = &wm9712_codec;
+               break;
+#endif
+#ifdef CONFIG_TOUCHSCREEN_WM9713
+       case 0x13:
+               wm->codec = &wm9713_codec;
+               break;
+#endif
+       default:
+               dev_err(wm->dev, "Support for wm97%02x not compiled in.\n",
+                       wm->id & 0xff);
+               ret = -ENODEV;
+               goto alloc_err;
+       }
+
+       wm->input_dev = input_allocate_device();
+       if (wm->input_dev == NULL) {
+               ret = -ENOMEM;
+               goto alloc_err;
+       }
+
+       /* set up touch configuration */
+       wm->input_dev->name = "wm97xx touchscreen";
+       wm->input_dev->open = wm97xx_ts_input_open;
+       wm->input_dev->close = wm97xx_ts_input_close;
+       set_bit(EV_ABS, wm->input_dev->evbit);
+       set_bit(ABS_X, wm->input_dev->absbit);
+       set_bit(ABS_Y, wm->input_dev->absbit);
+       set_bit(ABS_PRESSURE, wm->input_dev->absbit);
+       input_set_abs_params(wm->input_dev, ABS_X, abs_x[0], abs_x[1],
+                            abs_x[2], 0);
+       input_set_abs_params(wm->input_dev, ABS_Y, abs_y[0], abs_y[1],
+                            abs_y[2], 0);
+       input_set_abs_params(wm->input_dev, ABS_PRESSURE, abs_p[0], abs_p[1],
+                            abs_p[2], 0);
+       input_set_drvdata(wm->input_dev, wm);
+       wm->input_dev->dev.parent = dev;
+       ret = input_register_device(wm->input_dev);
+       if (ret < 0)
+               goto dev_alloc_err;
+
+       /* set up physical characteristics */
+       wm->codec->phy_init(wm);
+
+       /* load gpio cache */
+       wm->gpio[0] = wm97xx_reg_read(wm, AC97_GPIO_CFG);
+       wm->gpio[1] = wm97xx_reg_read(wm, AC97_GPIO_POLARITY);
+       wm->gpio[2] = wm97xx_reg_read(wm, AC97_GPIO_STICKY);
+       wm->gpio[3] = wm97xx_reg_read(wm, AC97_GPIO_WAKEUP);
+       wm->gpio[4] = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
+       wm->gpio[5] = wm97xx_reg_read(wm, AC97_MISC_AFE);
+
+       /* register our battery device */
+       wm->battery_dev = platform_device_alloc("wm97xx-battery", -1);
+       if (!wm->battery_dev) {
+               ret = -ENOMEM;
+               goto batt_err;
+       }
+       platform_set_drvdata(wm->battery_dev, wm);
+       wm->battery_dev->dev.parent = dev;
+       ret = platform_device_add(wm->battery_dev);
+       if (ret < 0)
+               goto batt_reg_err;
+
+       /* register our extended touch device (for machine specific
+        * extensions) */
+       wm->touch_dev = platform_device_alloc("wm97xx-touch", -1);
+       if (!wm->touch_dev) {
+               ret = -ENOMEM;
+               goto touch_err;
+       }
+       platform_set_drvdata(wm->touch_dev, wm);
+       wm->touch_dev->dev.parent = dev;
+       ret = platform_device_add(wm->touch_dev);
+       if (ret < 0)
+               goto touch_reg_err;
+
+       return ret;
+
+ touch_reg_err:
+       platform_device_put(wm->touch_dev);
+ touch_err:
+       platform_device_unregister(wm->battery_dev);
+       wm->battery_dev = NULL;
+ batt_reg_err:
+       platform_device_put(wm->battery_dev);
+ batt_err:
+       input_unregister_device(wm->input_dev);
+       wm->input_dev = NULL;
+ dev_alloc_err:
+       input_free_device(wm->input_dev);
+ alloc_err:
+       kfree(wm);
+
+       return ret;
+}
+
+static int wm97xx_remove(struct device *dev)
+{
+       struct wm97xx *wm = dev_get_drvdata(dev);
+
+       platform_device_unregister(wm->battery_dev);
+       platform_device_unregister(wm->touch_dev);
+       input_unregister_device(wm->input_dev);
+       kfree(wm);
+
+       return 0;
+}
+
+#ifdef CONFIG_PM
+static int wm97xx_suspend(struct device *dev, pm_message_t state)
+{
+       struct wm97xx *wm = dev_get_drvdata(dev);
+
+       if (wm->input_dev->users)
+               cancel_delayed_work_sync(&wm->ts_reader);
+
+       return 0;
+}
+
+static int wm97xx_resume(struct device *dev)
+{
+       struct wm97xx *wm = dev_get_drvdata(dev);
+
+       /* restore digitiser and gpios */
+       if (wm->id == WM9713_ID2) {
+               wm97xx_reg_write(wm, AC97_WM9713_DIG1, wm->dig[0]);
+               wm97xx_reg_write(wm, 0x5a, wm->misc);
+               if (wm->input_dev->users) {
+                       u16 reg;
+                       reg = wm97xx_reg_read(wm, AC97_EXTENDED_MID) & 0x7fff;
+                       wm97xx_reg_write(wm, AC97_EXTENDED_MID, reg);
+               }
+       }
+
+       wm97xx_reg_write(wm, AC97_WM9713_DIG2, wm->dig[1]);
+       wm97xx_reg_write(wm, AC97_WM9713_DIG3, wm->dig[2]);
+
+       wm97xx_reg_write(wm, AC97_GPIO_CFG, wm->gpio[0]);
+       wm97xx_reg_write(wm, AC97_GPIO_POLARITY, wm->gpio[1]);
+       wm97xx_reg_write(wm, AC97_GPIO_STICKY, wm->gpio[2]);
+       wm97xx_reg_write(wm, AC97_GPIO_WAKEUP, wm->gpio[3]);
+       wm97xx_reg_write(wm, AC97_GPIO_STATUS, wm->gpio[4]);
+       wm97xx_reg_write(wm, AC97_MISC_AFE, wm->gpio[5]);
+
+       if (wm->input_dev->users && !wm->pen_irq) {
+               wm->ts_reader_interval = wm->ts_reader_min_interval;
+               queue_delayed_work(wm->ts_workq, &wm->ts_reader,
+                                  wm->ts_reader_interval);
+       }
+
+       return 0;
+}
+
+#else
+#define wm97xx_suspend         NULL
+#define wm97xx_resume          NULL
+#endif
+
+/*
+ * Machine specific operations
+ */
+int wm97xx_register_mach_ops(struct wm97xx *wm,
+                            struct wm97xx_mach_ops *mach_ops)
+{
+       mutex_lock(&wm->codec_mutex);
+       if (wm->mach_ops) {
+               mutex_unlock(&wm->codec_mutex);
+               return -EINVAL;
+       }
+       wm->mach_ops = mach_ops;
+       mutex_unlock(&wm->codec_mutex);
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(wm97xx_register_mach_ops);
+
+void wm97xx_unregister_mach_ops(struct wm97xx *wm)
+{
+       mutex_lock(&wm->codec_mutex);
+       wm->mach_ops = NULL;
+       mutex_unlock(&wm->codec_mutex);
+}
+EXPORT_SYMBOL_GPL(wm97xx_unregister_mach_ops);
+
+static struct device_driver wm97xx_driver = {
+       .name =         "ac97",
+       .bus =          &ac97_bus_type,
+       .owner =        THIS_MODULE,
+       .probe =        wm97xx_probe,
+       .remove =       wm97xx_remove,
+       .suspend =      wm97xx_suspend,
+       .resume =       wm97xx_resume,
+};
+
+static int __init wm97xx_init(void)
+{
+       return driver_register(&wm97xx_driver);
+}
+
+static void __exit wm97xx_exit(void)
+{
+       driver_unregister(&wm97xx_driver);
+}
+
+module_init(wm97xx_init);
+module_exit(wm97xx_exit);
+
+/* Module information */
+MODULE_AUTHOR("Liam Girdwood <liam.girdwood@wolfsonmicro.com>");
+MODULE_DESCRIPTION("WM97xx Core - Touch Screen / AUX ADC / GPIO Driver");
+MODULE_LICENSE("GPL");
 
--- /dev/null
+
+/*
+ * Register bits and API for Wolfson WM97xx series of codecs
+ */
+
+#ifndef _LINUX_WM97XX_H
+#define _LINUX_WM97XX_H
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/ac97_codec.h>
+#include <sound/initval.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/input.h>       /* Input device layer */
+#include <linux/platform_device.h>
+
+/*
+ * WM97xx AC97 Touchscreen registers
+ */
+#define AC97_WM97XX_DIGITISER1         0x76
+#define AC97_WM97XX_DIGITISER2         0x78
+#define AC97_WM97XX_DIGITISER_RD       0x7a
+#define AC97_WM9713_DIG1               0x74
+#define AC97_WM9713_DIG2               AC97_WM97XX_DIGITISER1
+#define AC97_WM9713_DIG3               AC97_WM97XX_DIGITISER2
+
+/*
+ * WM97xx register bits
+ */
+#define WM97XX_POLL            0x8000  /* initiate a polling measurement */
+#define WM97XX_ADCSEL_X                0x1000  /* x coord measurement */
+#define WM97XX_ADCSEL_Y                0x2000  /* y coord measurement */
+#define WM97XX_ADCSEL_PRES     0x3000  /* pressure measurement */
+#define WM97XX_ADCSEL_MASK     0x7000
+#define WM97XX_COO             0x0800  /* enable coordinate mode */
+#define WM97XX_CTC             0x0400  /* enable continuous mode */
+#define WM97XX_CM_RATE_93      0x0000  /* 93.75Hz continuous rate */
+#define WM97XX_CM_RATE_187     0x0100  /* 187.5Hz continuous rate */
+#define WM97XX_CM_RATE_375     0x0200  /* 375Hz continuous rate */
+#define WM97XX_CM_RATE_750     0x0300  /* 750Hz continuous rate */
+#define WM97XX_CM_RATE_8K      0x00f0  /* 8kHz continuous rate */
+#define WM97XX_CM_RATE_12K     0x01f0  /* 12kHz continuous rate */
+#define WM97XX_CM_RATE_24K     0x02f0  /* 24kHz continuous rate */
+#define WM97XX_CM_RATE_48K     0x03f0  /* 48kHz continuous rate */
+#define WM97XX_CM_RATE_MASK    0x03f0
+#define WM97XX_RATE(i)         (((i & 3) << 8) | ((i & 4) ? 0xf0 : 0))
+#define WM97XX_DELAY(i)                ((i << 4) & 0x00f0)     /* sample delay times */
+#define WM97XX_DELAY_MASK      0x00f0
+#define WM97XX_SLEN            0x0008  /* slot read back enable */
+#define WM97XX_SLT(i)          ((i - 5) & 0x7) /* panel slot (5-11) */
+#define WM97XX_SLT_MASK                0x0007
+#define WM97XX_PRP_DETW                0x4000  /* detect on, digitise off, wake */
+#define WM97XX_PRP_DET         0x8000  /* detect on, digitise off, no wake */
+#define WM97XX_PRP_DET_DIG     0xc000  /* setect on, digitise on */
+#define WM97XX_RPR             0x2000  /* wake up on pen down */
+#define WM97XX_PEN_DOWN                0x8000  /* pen is down */
+#define WM97XX_ADCSRC_MASK     0x7000  /* ADC source mask */
+
+#define WM97XX_AUX_ID1         0x8001
+#define WM97XX_AUX_ID2         0x8002
+#define WM97XX_AUX_ID3         0x8003
+#define WM97XX_AUX_ID4         0x8004
+
+
+/* WM9712 Bits */
+#define WM9712_45W             0x1000  /* set for 5-wire touchscreen */
+#define WM9712_PDEN            0x0800  /* measure only when pen down */
+#define WM9712_WAIT            0x0200  /* wait until adc is read before next sample */
+#define WM9712_PIL             0x0100  /* current used for pressure measurement. set 400uA else 200uA */
+#define WM9712_MASK_HI         0x0040  /* hi on mask pin (47) stops conversions */
+#define WM9712_MASK_EDGE       0x0080  /* rising/falling edge on pin delays sample */
+#define        WM9712_MASK_SYNC        0x00c0  /* rising/falling edge on mask initiates sample */
+#define WM9712_RPU(i)          (i&0x3f)        /* internal pull up on pen detect (64k / rpu) */
+#define WM9712_PD(i)           (0x1 << i)      /* power management */
+
+/* WM9712 Registers */
+#define AC97_WM9712_POWER      0x24
+#define AC97_WM9712_REV                0x58
+
+/* WM9705 Bits */
+#define WM9705_PDEN            0x1000  /* measure only when pen is down */
+#define WM9705_PINV            0x0800  /* inverts sense of pen down output */
+#define WM9705_BSEN            0x0400  /* BUSY flag enable, pin47 is 1 when busy */
+#define WM9705_BINV            0x0200  /* invert BUSY (pin47) output */
+#define WM9705_WAIT            0x0100  /* wait until adc is read before next sample */
+#define WM9705_PIL             0x0080  /* current used for pressure measurement. set 400uA else 200uA */
+#define WM9705_PHIZ            0x0040  /* set PHONE and PCBEEP inputs to high impedance */
+#define WM9705_MASK_HI         0x0010  /* hi on mask stops conversions */
+#define WM9705_MASK_EDGE       0x0020  /* rising/falling edge on pin delays sample */
+#define        WM9705_MASK_SYNC        0x0030  /* rising/falling edge on mask initiates sample */
+#define WM9705_PDD(i)          (i & 0x000f)    /* pen detect comparator threshold */
+
+
+/* WM9713 Bits */
+#define WM9713_PDPOL           0x0400  /* Pen down polarity */
+#define WM9713_POLL            0x0200  /* initiate a polling measurement */
+#define WM9713_CTC             0x0100  /* enable continuous mode */
+#define WM9713_ADCSEL_X                0x0002  /* X measurement */
+#define WM9713_ADCSEL_Y                0x0004  /* Y measurement */
+#define WM9713_ADCSEL_PRES     0x0008  /* Pressure measurement */
+#define WM9713_COO             0x0001  /* enable coordinate mode */
+#define WM9713_PDEN            0x0800  /* measure only when pen down */
+#define WM9713_ADCSEL_MASK     0x00fe  /* ADC selection mask */
+#define WM9713_WAIT            0x0200  /* coordinate wait */
+
+/* AUX ADC ID's */
+#define TS_COMP1               0x0
+#define TS_COMP2               0x1
+#define TS_BMON                        0x2
+#define TS_WIPER               0x3
+
+/* ID numbers */
+#define WM97XX_ID1             0x574d
+#define WM9712_ID2             0x4c12
+#define WM9705_ID2             0x4c05
+#define WM9713_ID2             0x4c13
+
+/* Codec GPIO's */
+#define WM97XX_MAX_GPIO                16
+#define WM97XX_GPIO_1          (1 << 1)
+#define WM97XX_GPIO_2          (1 << 2)
+#define WM97XX_GPIO_3          (1 << 3)
+#define WM97XX_GPIO_4          (1 << 4)
+#define WM97XX_GPIO_5          (1 << 5)
+#define WM97XX_GPIO_6          (1 << 6)
+#define WM97XX_GPIO_7          (1 << 7)
+#define WM97XX_GPIO_8          (1 << 8)
+#define WM97XX_GPIO_9          (1 << 9)
+#define WM97XX_GPIO_10         (1 << 10)
+#define WM97XX_GPIO_11         (1 << 11)
+#define WM97XX_GPIO_12         (1 << 12)
+#define WM97XX_GPIO_13         (1 << 13)
+#define WM97XX_GPIO_14         (1 << 14)
+#define WM97XX_GPIO_15         (1 << 15)
+
+
+#define AC97_LINK_FRAME                21      /* time in uS for AC97 link frame */
+
+
+/*---------------- Return codes from sample reading functions ---------------*/
+
+/* More data is available; call the sample gathering function again */
+#define RC_AGAIN                       0x00000001
+/* The returned sample is valid */
+#define RC_VALID                       0x00000002
+/* The pen is up (the first RC_VALID without RC_PENUP means pen is down) */
+#define RC_PENUP                       0x00000004
+/* The pen is down (RC_VALID implies RC_PENDOWN, but sometimes it is helpful
+   to tell the handler that the pen is down but we don't know yet his coords,
+   so the handler should not sleep or wait for pendown irq) */
+#define RC_PENDOWN                     0x00000008
+
+/*
+ * The wm97xx driver provides a private API for writing platform-specific
+ * drivers.
+ */
+
+/* The structure used to return arch specific sampled data into */
+struct wm97xx_data {
+    int x;
+    int y;
+    int p;
+};
+
+/*
+ * Codec GPIO status
+ */
+enum wm97xx_gpio_status {
+    WM97XX_GPIO_HIGH,
+    WM97XX_GPIO_LOW
+};
+
+/*
+ * Codec GPIO direction
+ */
+enum wm97xx_gpio_dir {
+    WM97XX_GPIO_IN,
+    WM97XX_GPIO_OUT
+};
+
+/*
+ * Codec GPIO polarity
+ */
+enum wm97xx_gpio_pol {
+    WM97XX_GPIO_POL_HIGH,
+    WM97XX_GPIO_POL_LOW
+};
+
+/*
+ * Codec GPIO sticky
+ */
+enum wm97xx_gpio_sticky {
+    WM97XX_GPIO_STICKY,
+    WM97XX_GPIO_NOTSTICKY
+};
+
+/*
+ * Codec GPIO wake
+ */
+enum wm97xx_gpio_wake {
+    WM97XX_GPIO_WAKE,
+    WM97XX_GPIO_NOWAKE
+};
+
+/*
+ * Digitiser ioctl commands
+ */
+#define WM97XX_DIG_START       0x1
+#define WM97XX_DIG_STOP                0x2
+#define WM97XX_PHY_INIT                0x3
+#define WM97XX_AUX_PREPARE     0x4
+#define WM97XX_DIG_RESTORE     0x5
+
+struct wm97xx;
+
+extern struct wm97xx_codec_drv wm9705_codec;
+extern struct wm97xx_codec_drv wm9712_codec;
+extern struct wm97xx_codec_drv wm9713_codec;
+
+/*
+ * Codec driver interface - allows mapping to WM9705/12/13 and newer codecs
+ */
+struct wm97xx_codec_drv {
+       u16 id;
+       char *name;
+
+       /* read 1 sample */
+       int (*poll_sample) (struct wm97xx *, int adcsel, int *sample);
+
+       /* read X,Y,[P] in poll */
+       int (*poll_touch) (struct wm97xx *, struct wm97xx_data *);
+
+       int (*acc_enable) (struct wm97xx *, int enable);
+       void (*phy_init) (struct wm97xx *);
+       void (*dig_enable) (struct wm97xx *, int enable);
+       void (*dig_restore) (struct wm97xx *);
+       void (*aux_prepare) (struct wm97xx *);
+};
+
+
+/* Machine specific and accelerated touch operations */
+struct wm97xx_mach_ops {
+
+       /* accelerated touch readback - coords are transmited on AC97 link */
+       int acc_enabled;
+       void (*acc_pen_up) (struct wm97xx *);
+       int (*acc_pen_down) (struct wm97xx *);
+       int (*acc_startup) (struct wm97xx *);
+       void (*acc_shutdown) (struct wm97xx *);
+
+       /* interrupt mask control - required for accelerated operation */
+       void (*irq_enable) (struct wm97xx *, int enable);
+
+       /* GPIO pin used for accelerated operation */
+       int irq_gpio;
+
+       /* pre and post sample - can be used to minimise any analog noise */
+       void (*pre_sample) (int);  /* function to run before sampling */
+       void (*post_sample) (int);  /* function to run after sampling */
+};
+
+struct wm97xx {
+       u16 dig[3], id, gpio[6], misc;  /* Cached codec registers */
+       u16 dig_save[3];                /* saved during aux reading */
+       struct wm97xx_codec_drv *codec; /* attached codec driver*/
+       struct input_dev *input_dev;    /* touchscreen input device */
+       struct snd_ac97 *ac97;          /* ALSA codec access */
+       struct device *dev;             /* ALSA device */
+       struct platform_device *battery_dev;
+       struct platform_device *touch_dev;
+       struct wm97xx_mach_ops *mach_ops;
+       struct mutex codec_mutex;
+       struct delayed_work ts_reader;  /* Used to poll touchscreen */
+       unsigned long ts_reader_interval; /* Current interval for timer */
+       unsigned long ts_reader_min_interval; /* Minimum interval */
+       unsigned int pen_irq;           /* Pen IRQ number in use */
+       struct workqueue_struct *ts_workq;
+       struct work_struct pen_event_work;
+       u16 acc_slot;                   /* AC97 slot used for acc touch data */
+       u16 acc_rate;                   /* acc touch data rate */
+       unsigned pen_is_down:1;         /* Pen is down */
+       unsigned aux_waiting:1;         /* aux measurement waiting */
+       unsigned pen_probably_down:1;   /* used in polling mode */
+};
+
+/*
+ * Codec GPIO access (not supported on WM9705)
+ * This can be used to set/get codec GPIO and Virtual GPIO status.
+ */
+enum wm97xx_gpio_status wm97xx_get_gpio(struct wm97xx *wm, u32 gpio);
+void wm97xx_set_gpio(struct wm97xx *wm, u32 gpio,
+                         enum wm97xx_gpio_status status);
+void wm97xx_config_gpio(struct wm97xx *wm, u32 gpio,
+                                    enum wm97xx_gpio_dir dir,
+                                    enum wm97xx_gpio_pol pol,
+                                    enum wm97xx_gpio_sticky sticky,
+                                    enum wm97xx_gpio_wake wake);
+
+/* codec AC97 IO access */
+int wm97xx_reg_read(struct wm97xx *wm, u16 reg);
+void wm97xx_reg_write(struct wm97xx *wm, u16 reg, u16 val);
+
+/* aux adc readback */
+int wm97xx_read_aux_adc(struct wm97xx *wm, u16 adcsel);
+
+/* machine ops */
+int wm97xx_register_mach_ops(struct wm97xx *, struct wm97xx_mach_ops *);
+void wm97xx_unregister_mach_ops(struct wm97xx *);
+
+#endif