Adding upstream version 6.1.76.upstream/6.1.76upstream

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

1 files changed, 910 insertions, 0 deletions

diff --git a/drivers/input/touchscreen/wm97xx-core.c b/drivers/input/touchscreen/wm97xx-core.c
new file mode 100644
index 000000000..f51ab5614
--- /dev/null
+++ b/drivers/input/touchscreen/wm97xx-core.c
@@ -0,0 +1,910 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 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 <lrg@slimlogic.co.uk>
+ * Parts Copyright : Ian Molton <spyro@f2s.com>
+ *                   Andrew Zabolotny <zap@homelink.ru>
+ *                   Russell King <rmk@arm.linux.org.uk>
+ *
+ * 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/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/mfd/wm97xx.h>
+#include <linux/workqueue.h>
+#include <linux/wm97xx.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+#include <linux/slab.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.rst for more details.
+ */
+
+static int abs_x[3] = {150, 4000, 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] = {200, 4000, 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;
+	int rc = 0;
+	int timeout = 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;
+
+	while (rc != RC_VALID && timeout++ < 5)
+		rc = 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;
+
+	if (timeout >= 5) {
+		dev_err(wm->dev,
+			"timeout reading auxadc %d, disabling digitiser\n",
+			adcsel);
+		wm->codec->dig_enable(wm, false);
+	}
+
+	mutex_unlock(&wm->codec_mutex);
+	return (rc == RC_VALID ? auxval & 0xfff : -EBUSY);
+}
+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
+ * @status: status
+ *
+ * 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 && wm->variant != WM97xx_WM1613)
+		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);
+
+/*
+ * Configure the WM97XX_PRP value to use while system is suspended.
+ * If a value other than 0 is set then WM97xx pen detection will be
+ * left enabled in the configured mode while the system is in suspend,
+ * the device has users and suspend has not been disabled via the
+ * wakeup sysfs entries.
+ *
+ * @wm:   WM97xx device to configure
+ * @mode: WM97XX_PRP value to configure while suspended
+ */
+void wm97xx_set_suspend_mode(struct wm97xx *wm, u16 mode)
+{
+	wm->suspend_mode = mode;
+	device_init_wakeup(&wm->input_dev->dev, mode != 0);
+}
+EXPORT_SYMBOL_GPL(wm97xx_set_suspend_mode);
+
+/*
+ * Codec PENDOWN irq handler
+ *
+ */
+static irqreturn_t wm97xx_pen_interrupt(int irq, void *dev_id)
+{
+	struct wm97xx *wm = dev_id;
+	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 && wm->variant != WM97xx_WM1613)
+			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 available 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);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * initialise pen IRQ handler and workqueue
+ */
+static int wm97xx_init_pen_irq(struct wm97xx *wm)
+{
+	u16 reg;
+
+	if (request_threaded_irq(wm->pen_irq, NULL, wm97xx_pen_interrupt,
+				 IRQF_SHARED | IRQF_ONESHOT,
+				 "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_report_key(wm->input_dev, BTN_TOUCH, 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);
+
+		if (abs_x[0] > (data.x & 0xfff) ||
+		    abs_x[1] < (data.x & 0xfff) ||
+		    abs_y[0] > (data.y & 0xfff) ||
+		    abs_y[1] < (data.y & 0xfff)) {
+			dev_dbg(wm->dev, "Measurement out of range, dropping it\n");
+			rc = RC_AGAIN;
+			goto out;
+		}
+
+		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_report_key(wm->input_dev, BTN_TOUCH, 1);
+		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;
+	}
+
+out:
+	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 = alloc_ordered_workqueue("kwm97xx", 0);
+	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);
+
+	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;
+
+	/* 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_register_touch(struct wm97xx *wm)
+{
+	struct wm97xx_pdata *pdata = dev_get_platdata(wm->dev);
+	int ret;
+
+	wm->input_dev = devm_input_allocate_device(wm->dev);
+	if (wm->input_dev == NULL)
+		return -ENOMEM;
+
+	/* set up touch configuration */
+	wm->input_dev->name = "wm97xx touchscreen";
+	wm->input_dev->phys = "wm97xx";
+	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(EV_KEY, wm->input_dev->evbit);
+	__set_bit(BTN_TOUCH, wm->input_dev->keybit);
+
+	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 = wm->dev;
+
+	ret = input_register_device(wm->input_dev);
+	if (ret)
+		return ret;
+
+	/*
+	 * register our extended touch device (for machine specific
+	 * extensions)
+	 */
+	wm->touch_dev = platform_device_alloc("wm97xx-touch", -1);
+	if (!wm->touch_dev)
+		return -ENOMEM;
+
+	platform_set_drvdata(wm->touch_dev, wm);
+	wm->touch_dev->dev.parent = wm->dev;
+	wm->touch_dev->dev.platform_data = pdata;
+	ret = platform_device_add(wm->touch_dev);
+	if (ret < 0)
+		goto touch_reg_err;
+
+	return 0;
+touch_reg_err:
+	platform_device_put(wm->touch_dev);
+
+	return ret;
+}
+
+static void wm97xx_unregister_touch(struct wm97xx *wm)
+{
+	platform_device_unregister(wm->touch_dev);
+}
+
+static int _wm97xx_probe(struct wm97xx *wm)
+{
+	int id = 0;
+
+	mutex_init(&wm->codec_mutex);
+	dev_set_drvdata(wm->dev, wm);
+
+	/* check that we have a supported codec */
+	id = wm97xx_reg_read(wm, AC97_VENDOR_ID1);
+	if (id != WM97XX_ID1) {
+		dev_err(wm->dev,
+			"Device with vendor %04x is not a wm97xx\n", id);
+		return -ENODEV;
+	}
+
+	wm->id = wm97xx_reg_read(wm, AC97_VENDOR_ID2);
+
+	wm->variant = WM97xx_GENERIC;
+
+	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);
+		return -ENODEV;
+	}
+
+	/* 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);
+
+	return wm97xx_register_touch(wm);
+}
+
+static void wm97xx_remove_battery(struct wm97xx *wm)
+{
+	platform_device_unregister(wm->battery_dev);
+}
+
+static int wm97xx_add_battery(struct wm97xx *wm,
+			      struct wm97xx_batt_pdata *pdata)
+{
+	int ret;
+
+	wm->battery_dev = platform_device_alloc("wm97xx-battery", -1);
+	if (!wm->battery_dev)
+		return -ENOMEM;
+
+	platform_set_drvdata(wm->battery_dev, wm);
+	wm->battery_dev->dev.parent = wm->dev;
+	wm->battery_dev->dev.platform_data = pdata;
+	ret = platform_device_add(wm->battery_dev);
+	if (ret)
+		platform_device_put(wm->battery_dev);
+
+	return ret;
+}
+
+static int wm97xx_probe(struct device *dev)
+{
+	struct wm97xx *wm;
+	int ret;
+	struct wm97xx_pdata *pdata = dev_get_platdata(dev);
+
+	wm = devm_kzalloc(dev, sizeof(struct wm97xx), GFP_KERNEL);
+	if (!wm)
+		return -ENOMEM;
+
+	wm->dev = dev;
+	wm->ac97 = to_ac97_t(dev);
+
+	ret =  _wm97xx_probe(wm);
+	if (ret)
+		return ret;
+
+	ret = wm97xx_add_battery(wm, pdata ? pdata->batt_pdata : NULL);
+	if (ret < 0)
+		goto batt_err;
+
+	return ret;
+
+batt_err:
+	wm97xx_unregister_touch(wm);
+	return ret;
+}
+
+static int wm97xx_remove(struct device *dev)
+{
+	struct wm97xx *wm = dev_get_drvdata(dev);
+
+	wm97xx_remove_battery(wm);
+	wm97xx_unregister_touch(wm);
+
+	return 0;
+}
+
+static int wm97xx_mfd_probe(struct platform_device *pdev)
+{
+	struct wm97xx *wm;
+	struct wm97xx_platform_data *mfd_pdata = dev_get_platdata(&pdev->dev);
+	int ret;
+
+	wm = devm_kzalloc(&pdev->dev, sizeof(struct wm97xx), GFP_KERNEL);
+	if (!wm)
+		return -ENOMEM;
+
+	wm->dev = &pdev->dev;
+	wm->ac97 = mfd_pdata->ac97;
+
+	ret =  _wm97xx_probe(wm);
+	if (ret)
+		return ret;
+
+	ret = wm97xx_add_battery(wm, mfd_pdata->batt_pdata);
+	if (ret < 0)
+		goto batt_err;
+
+	return ret;
+
+batt_err:
+	wm97xx_unregister_touch(wm);
+	return ret;
+}
+
+static int wm97xx_mfd_remove(struct platform_device *pdev)
+{
+	wm97xx_remove(&pdev->dev);
+
+	return 0;
+}
+
+static int __maybe_unused wm97xx_suspend(struct device *dev)
+{
+	struct wm97xx *wm = dev_get_drvdata(dev);
+	u16 reg;
+	int suspend_mode;
+
+	if (device_may_wakeup(&wm->input_dev->dev))
+		suspend_mode = wm->suspend_mode;
+	else
+		suspend_mode = 0;
+
+	mutex_lock(&wm->input_dev->mutex);
+	if (input_device_enabled(wm->input_dev))
+		cancel_delayed_work_sync(&wm->ts_reader);
+
+	/* Power down the digitiser (bypassing the cache for resume) */
+	reg = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER2);
+	reg &= ~WM97XX_PRP_DET_DIG;
+	if (input_device_enabled(wm->input_dev))
+		reg |= suspend_mode;
+	wm->ac97->bus->ops->write(wm->ac97, AC97_WM97XX_DIGITISER2, reg);
+
+	/* WM9713 has an additional power bit - turn it off if there
+	 * are no users or if suspend mode is zero. */
+	if (wm->id == WM9713_ID2 &&
+	    (!input_device_enabled(wm->input_dev) || !suspend_mode)) {
+		reg = wm97xx_reg_read(wm, AC97_EXTENDED_MID) | 0x8000;
+		wm97xx_reg_write(wm, AC97_EXTENDED_MID, reg);
+	}
+	mutex_unlock(&wm->input_dev->mutex);
+
+	return 0;
+}
+
+static int __maybe_unused wm97xx_resume(struct device *dev)
+{
+	struct wm97xx *wm = dev_get_drvdata(dev);
+
+	mutex_lock(&wm->input_dev->mutex);
+	/* 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 (input_device_enabled(wm->input_dev)) {
+			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 (input_device_enabled(wm->input_dev) && !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);
+	}
+	mutex_unlock(&wm->input_dev->mutex);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(wm97xx_pm_ops, wm97xx_suspend, wm97xx_resume);
+
+/*
+ * 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 =		"wm97xx-ts",
+#ifdef CONFIG_AC97_BUS
+	.bus =		&ac97_bus_type,
+#endif
+	.owner =	THIS_MODULE,
+	.probe =	wm97xx_probe,
+	.remove =	wm97xx_remove,
+	.pm =		&wm97xx_pm_ops,
+};
+
+static struct platform_driver wm97xx_mfd_driver = {
+	.driver = {
+		.name =		"wm97xx-ts",
+		.pm =		&wm97xx_pm_ops,
+	},
+	.probe =	wm97xx_mfd_probe,
+	.remove =	wm97xx_mfd_remove,
+};
+
+static int __init wm97xx_init(void)
+{
+	int ret;
+
+	ret = platform_driver_register(&wm97xx_mfd_driver);
+	if (ret)
+		return ret;
+
+	if (IS_BUILTIN(CONFIG_AC97_BUS))
+		ret =  driver_register(&wm97xx_driver);
+	return ret;
+}
+
+static void __exit wm97xx_exit(void)
+{
+	if (IS_BUILTIN(CONFIG_AC97_BUS))
+		driver_unregister(&wm97xx_driver);
+	platform_driver_unregister(&wm97xx_mfd_driver);
+}
+
+module_init(wm97xx_init);
+module_exit(wm97xx_exit);
+
+/* Module information */
+MODULE_AUTHOR("Liam Girdwood <lrg@slimlogic.co.uk>");
+MODULE_DESCRIPTION("WM97xx Core - Touch Screen / AUX ADC / GPIO Driver");
+MODULE_LICENSE("GPL");