drivers/input/touchscreen/wm831x-ts.c - linux - Git at Google

 /*
  * Touchscreen driver for WM831x PMICs
  *
  * Copyright 2011 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/module.h>
 #include <linux/moduleparam.h>
 #include <linux/kernel.h>
 #include <linux/string.h>
 #include <linux/pm.h>
 #include <linux/input.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/mfd/wm831x/core.h>
 #include <linux/mfd/wm831x/irq.h>
 #include <linux/mfd/wm831x/pdata.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/types.h>

 /*
  * R16424 (0x4028) - Touch Control 1
  */
 #define WM831X_TCH_ENA                          0x8000  /* TCH_ENA */
 #define WM831X_TCH_CVT_ENA                      0x4000  /* TCH_CVT_ENA */
 #define WM831X_TCH_SLPENA                       0x1000  /* TCH_SLPENA */
 #define WM831X_TCH_Z_ENA                        0x0400  /* TCH_Z_ENA */
 #define WM831X_TCH_Y_ENA                        0x0200  /* TCH_Y_ENA */
 #define WM831X_TCH_X_ENA                        0x0100  /* TCH_X_ENA */
 #define WM831X_TCH_DELAY_MASK                   0x00E0  /* TCH_DELAY - [7:5] */
 #define WM831X_TCH_DELAY_SHIFT                       5  /* TCH_DELAY - [7:5] */
 #define WM831X_TCH_DELAY_WIDTH                       3  /* TCH_DELAY - [7:5] */
 #define WM831X_TCH_RATE_MASK                    0x001F  /* TCH_RATE - [4:0] */
 #define WM831X_TCH_RATE_SHIFT                        0  /* TCH_RATE - [4:0] */
 #define WM831X_TCH_RATE_WIDTH                        5  /* TCH_RATE - [4:0] */

 /*
  * R16425 (0x4029) - Touch Control 2
  */
 #define WM831X_TCH_PD_WK                        0x2000  /* TCH_PD_WK */
 #define WM831X_TCH_5WIRE                        0x1000  /* TCH_5WIRE */
 #define WM831X_TCH_PDONLY                       0x0800  /* TCH_PDONLY */
 #define WM831X_TCH_ISEL                         0x0100  /* TCH_ISEL */
 #define WM831X_TCH_RPU_MASK                     0x000F  /* TCH_RPU - [3:0] */
 #define WM831X_TCH_RPU_SHIFT                         0  /* TCH_RPU - [3:0] */
 #define WM831X_TCH_RPU_WIDTH                         4  /* TCH_RPU - [3:0] */

 /*
  * R16426-8 (0x402A-C) - Touch Data X/Y/X
  */
 #define WM831X_TCH_PD                           0x8000  /* TCH_PD1 */
 #define WM831X_TCH_DATA_MASK                    0x0FFF  /* TCH_DATA - [11:0] */
 #define WM831X_TCH_DATA_SHIFT                        0  /* TCH_DATA - [11:0] */
 #define WM831X_TCH_DATA_WIDTH                       12  /* TCH_DATA - [11:0] */

 struct wm831x_ts {
 	struct input_dev *input_dev;
 	struct wm831x *wm831x;
 	unsigned int data_irq;
 	unsigned int pd_irq;
 	bool pressure;
 	bool pen_down;
 	struct work_struct pd_data_work;
 };

 static void wm831x_pd_data_work(struct work_struct *work)
 {
 	struct wm831x_ts *wm831x_ts =
 		container_of(work, struct wm831x_ts, pd_data_work);

 	if (wm831x_ts->pen_down) {
 		enable_irq(wm831x_ts->data_irq);
 		dev_dbg(wm831x_ts->wm831x->dev, "IRQ PD->DATA done\n");
 	} else {
 		enable_irq(wm831x_ts->pd_irq);
 		dev_dbg(wm831x_ts->wm831x->dev, "IRQ DATA->PD done\n");
 	}
 }

 static irqreturn_t wm831x_ts_data_irq(int irq, void *irq_data)
 {
 	struct wm831x_ts *wm831x_ts = irq_data;
 	struct wm831x *wm831x = wm831x_ts->wm831x;
 	static int data_types[] = { ABS_X, ABS_Y, ABS_PRESSURE };
 	u16 data[3];
 	int count;
 	int i, ret;

 	if (wm831x_ts->pressure)
 		count = 3;
 	else
 		count = 2;

 	wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
 			WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT);

 	ret = wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count,
 			       data);
 	if (ret != 0) {
 		dev_err(wm831x->dev, "Failed to read touch data: %d\n",
 			ret);
 		return IRQ_NONE;
 	}

 	/*
 	 * We get a pen down reading on every reading, report pen up if any
 	 * individual reading does so.
 	 */
 	wm831x_ts->pen_down = true;
 	for (i = 0; i < count; i++) {
 		if (!(data[i] & WM831X_TCH_PD)) {
 			wm831x_ts->pen_down = false;
 			continue;
 		}
 		input_report_abs(wm831x_ts->input_dev, data_types[i],
 				 data[i] & WM831X_TCH_DATA_MASK);
 	}

 	if (!wm831x_ts->pen_down) {
 		/* Switch from data to pen down */
 		dev_dbg(wm831x->dev, "IRQ DATA->PD\n");

 		disable_irq_nosync(wm831x_ts->data_irq);

 		/* Don't need data any more */
 		wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
 				WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA |
 				WM831X_TCH_Z_ENA, 0);

 		/* Flush any final samples that arrived while reading */
 		wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
 				WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT);

 		wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count, data);

 		if (wm831x_ts->pressure)
 			input_report_abs(wm831x_ts->input_dev,
 					 ABS_PRESSURE, 0);

 		input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 0);

 		schedule_work(&wm831x_ts->pd_data_work);
 	} else {
 		input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 1);
 	}

 	input_sync(wm831x_ts->input_dev);

 	return IRQ_HANDLED;
 }

 static irqreturn_t wm831x_ts_pen_down_irq(int irq, void *irq_data)
 {
 	struct wm831x_ts *wm831x_ts = irq_data;
 	struct wm831x *wm831x = wm831x_ts->wm831x;
 	int ena = 0;

 	if (wm831x_ts->pen_down)
 		return IRQ_HANDLED;

 	disable_irq_nosync(wm831x_ts->pd_irq);

 	/* Start collecting data */
 	if (wm831x_ts->pressure)
 		ena |= WM831X_TCH_Z_ENA;

 	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
 			WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | WM831X_TCH_Z_ENA,
 			WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | ena);

 	wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
 			WM831X_TCHPD_EINT, WM831X_TCHPD_EINT);

 	wm831x_ts->pen_down = true;

 	/* Switch from pen down to data */
 	dev_dbg(wm831x->dev, "IRQ PD->DATA\n");
 	schedule_work(&wm831x_ts->pd_data_work);

 	return IRQ_HANDLED;
 }

 static int wm831x_ts_input_open(struct input_dev *idev)
 {
 	struct wm831x_ts *wm831x_ts = input_get_drvdata(idev);
 	struct wm831x *wm831x = wm831x_ts->wm831x;

 	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
 			WM831X_TCH_ENA | WM831X_TCH_CVT_ENA |
 			WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA |
 			WM831X_TCH_Z_ENA, WM831X_TCH_ENA);

 	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
 			WM831X_TCH_CVT_ENA, WM831X_TCH_CVT_ENA);

 	return 0;
 }

 static void wm831x_ts_input_close(struct input_dev *idev)
 {
 	struct wm831x_ts *wm831x_ts = input_get_drvdata(idev);
 	struct wm831x *wm831x = wm831x_ts->wm831x;

 	/* Shut the controller down, disabling all other functionality too */
 	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
 			WM831X_TCH_ENA | WM831X_TCH_X_ENA |
 			WM831X_TCH_Y_ENA | WM831X_TCH_Z_ENA, 0);

 	/* Make sure any pending IRQs are done, the above will prevent
 	 * new ones firing.
 	 */
 	synchronize_irq(wm831x_ts->data_irq);
 	synchronize_irq(wm831x_ts->pd_irq);

 	/* Make sure the IRQ completion work is quiesced */
 	flush_work(&wm831x_ts->pd_data_work);

 	/* If we ended up with the pen down then make sure we revert back
 	 * to pen detection state for the next time we start up.
 	 */
 	if (wm831x_ts->pen_down) {
 		disable_irq(wm831x_ts->data_irq);
 		enable_irq(wm831x_ts->pd_irq);
 		wm831x_ts->pen_down = false;
 	}
 }

 static int wm831x_ts_probe(struct platform_device *pdev)
 {
 	struct wm831x_ts *wm831x_ts;
 	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
 	struct wm831x_pdata *core_pdata = dev_get_platdata(pdev->dev.parent);
 	struct wm831x_touch_pdata *pdata = NULL;
 	struct input_dev *input_dev;
 	int error, irqf;

 	if (core_pdata)
 		pdata = core_pdata->touch;

 	wm831x_ts = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_ts),
 				 GFP_KERNEL);
 	input_dev = devm_input_allocate_device(&pdev->dev);
 	if (!wm831x_ts || !input_dev) {
 		error = -ENOMEM;
 		goto err_alloc;
 	}

 	wm831x_ts->wm831x = wm831x;
 	wm831x_ts->input_dev = input_dev;
 	INIT_WORK(&wm831x_ts->pd_data_work, wm831x_pd_data_work);

 	/*
 	 * If we have a direct IRQ use it, otherwise use the interrupt
 	 * from the WM831x IRQ controller.
 	 */
 	wm831x_ts->data_irq = wm831x_irq(wm831x,
 					 platform_get_irq_byname(pdev,
 								 "TCHDATA"));
 	if (pdata && pdata->data_irq)
 		wm831x_ts->data_irq = pdata->data_irq;

 	wm831x_ts->pd_irq = wm831x_irq(wm831x,
 				       platform_get_irq_byname(pdev, "TCHPD"));
 	if (pdata && pdata->pd_irq)
 		wm831x_ts->pd_irq = pdata->pd_irq;

 	if (pdata)
 		wm831x_ts->pressure = pdata->pressure;
 	else
 		wm831x_ts->pressure = true;

 	/* Five wire touchscreens can't report pressure */
 	if (pdata && pdata->fivewire) {
 		wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
 				WM831X_TCH_5WIRE, WM831X_TCH_5WIRE);

 		/* Pressure measurements are not possible for five wire mode */
 		WARN_ON(pdata->pressure && pdata->fivewire);
 		wm831x_ts->pressure = false;
 	} else {
 		wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
 				WM831X_TCH_5WIRE, 0);
 	}

 	if (pdata) {
 		switch (pdata->isel) {
 		default:
 			dev_err(&pdev->dev, "Unsupported ISEL setting: %d\n",
 				pdata->isel);
 			/* Fall through */
 		case 200:
 		case 0:
 			wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
 					WM831X_TCH_ISEL, 0);
 			break;
 		case 400:
 			wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
 					WM831X_TCH_ISEL, WM831X_TCH_ISEL);
 			break;
 		}
 	}

 	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
 			WM831X_TCH_PDONLY, 0);

 	/* Default to 96 samples/sec */
 	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
 			WM831X_TCH_RATE_MASK, 6);

 	if (pdata && pdata->data_irqf)
 		irqf = pdata->data_irqf;
 	else
 		irqf = IRQF_TRIGGER_HIGH;

 	error = request_threaded_irq(wm831x_ts->data_irq,
 				     NULL, wm831x_ts_data_irq,
 				     irqf | IRQF_ONESHOT,
 				     "Touchscreen data", wm831x_ts);
 	if (error) {
 		dev_err(&pdev->dev, "Failed to request data IRQ %d: %d\n",
 			wm831x_ts->data_irq, error);
 		goto err_alloc;
 	}
 	disable_irq(wm831x_ts->data_irq);

 	if (pdata && pdata->pd_irqf)
 		irqf = pdata->pd_irqf;
 	else
 		irqf = IRQF_TRIGGER_HIGH;

 	error = request_threaded_irq(wm831x_ts->pd_irq,
 				     NULL, wm831x_ts_pen_down_irq,
 				     irqf | IRQF_ONESHOT,
 				     "Touchscreen pen down", wm831x_ts);
 	if (error) {
 		dev_err(&pdev->dev, "Failed to request pen down IRQ %d: %d\n",
 			wm831x_ts->pd_irq, error);
 		goto err_data_irq;
 	}

 	/* set up touch configuration */
 	input_dev->name = "WM831x touchscreen";
 	input_dev->phys = "wm831x";
 	input_dev->open = wm831x_ts_input_open;
 	input_dev->close = wm831x_ts_input_close;

 	__set_bit(EV_ABS, input_dev->evbit);
 	__set_bit(EV_KEY, input_dev->evbit);
 	__set_bit(BTN_TOUCH, input_dev->keybit);

 	input_set_abs_params(input_dev, ABS_X, 0, 4095, 5, 0);
 	input_set_abs_params(input_dev, ABS_Y, 0, 4095, 5, 0);
 	if (wm831x_ts->pressure)
 		input_set_abs_params(input_dev, ABS_PRESSURE, 0, 4095, 5, 0);

 	input_set_drvdata(input_dev, wm831x_ts);
 	input_dev->dev.parent = &pdev->dev;

 	error = input_register_device(input_dev);
 	if (error)
 		goto err_pd_irq;

 	platform_set_drvdata(pdev, wm831x_ts);
 	return 0;

 err_pd_irq:
 	free_irq(wm831x_ts->pd_irq, wm831x_ts);
 err_data_irq:
 	free_irq(wm831x_ts->data_irq, wm831x_ts);
 err_alloc:

 	return error;
 }

 static int wm831x_ts_remove(struct platform_device *pdev)
 {
 	struct wm831x_ts *wm831x_ts = platform_get_drvdata(pdev);

 	free_irq(wm831x_ts->pd_irq, wm831x_ts);
 	free_irq(wm831x_ts->data_irq, wm831x_ts);

 	return 0;
 }

 static struct platform_driver wm831x_ts_driver = {
 	.driver = {
 		.name = "wm831x-touch",
 	},
 	.probe = wm831x_ts_probe,
 	.remove = wm831x_ts_remove,
 };
 module_platform_driver(wm831x_ts_driver);

 /* Module information */
 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 MODULE_DESCRIPTION("WM831x PMIC touchscreen driver");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:wm831x-touch");
	/*
	* Touchscreen driver for WM831x PMICs
	*
	* Copyright 2011 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/module.h>
	#include <linux/moduleparam.h>
	#include <linux/kernel.h>
	#include <linux/string.h>
	#include <linux/pm.h>
	#include <linux/input.h>
	#include <linux/interrupt.h>
	#include <linux/io.h>
	#include <linux/mfd/wm831x/core.h>
	#include <linux/mfd/wm831x/irq.h>
	#include <linux/mfd/wm831x/pdata.h>
	#include <linux/platform_device.h>
	#include <linux/slab.h>
	#include <linux/types.h>

	/*
	* R16424 (0x4028) - Touch Control 1
	*/
	#define WM831X_TCH_ENA 0x8000 /* TCH_ENA */
	#define WM831X_TCH_CVT_ENA 0x4000 /* TCH_CVT_ENA */
	#define WM831X_TCH_SLPENA 0x1000 /* TCH_SLPENA */
	#define WM831X_TCH_Z_ENA 0x0400 /* TCH_Z_ENA */
	#define WM831X_TCH_Y_ENA 0x0200 /* TCH_Y_ENA */
	#define WM831X_TCH_X_ENA 0x0100 /* TCH_X_ENA */
	#define WM831X_TCH_DELAY_MASK 0x00E0 /* TCH_DELAY - [7:5] */
	#define WM831X_TCH_DELAY_SHIFT 5 /* TCH_DELAY - [7:5] */
	#define WM831X_TCH_DELAY_WIDTH 3 /* TCH_DELAY - [7:5] */
	#define WM831X_TCH_RATE_MASK 0x001F /* TCH_RATE - [4:0] */
	#define WM831X_TCH_RATE_SHIFT 0 /* TCH_RATE - [4:0] */
	#define WM831X_TCH_RATE_WIDTH 5 /* TCH_RATE - [4:0] */

	/*
	* R16425 (0x4029) - Touch Control 2
	*/
	#define WM831X_TCH_PD_WK 0x2000 /* TCH_PD_WK */
	#define WM831X_TCH_5WIRE 0x1000 /* TCH_5WIRE */
	#define WM831X_TCH_PDONLY 0x0800 /* TCH_PDONLY */
	#define WM831X_TCH_ISEL 0x0100 /* TCH_ISEL */
	#define WM831X_TCH_RPU_MASK 0x000F /* TCH_RPU - [3:0] */
	#define WM831X_TCH_RPU_SHIFT 0 /* TCH_RPU - [3:0] */
	#define WM831X_TCH_RPU_WIDTH 4 /* TCH_RPU - [3:0] */

	/*
	* R16426-8 (0x402A-C) - Touch Data X/Y/X
	*/
	#define WM831X_TCH_PD 0x8000 /* TCH_PD1 */
	#define WM831X_TCH_DATA_MASK 0x0FFF /* TCH_DATA - [11:0] */
	#define WM831X_TCH_DATA_SHIFT 0 /* TCH_DATA - [11:0] */
	#define WM831X_TCH_DATA_WIDTH 12 /* TCH_DATA - [11:0] */

	struct wm831x_ts {
	struct input_dev *input_dev;
	struct wm831x *wm831x;
	unsigned int data_irq;
	unsigned int pd_irq;
	bool pressure;
	bool pen_down;
	struct work_struct pd_data_work;
	};

	static void wm831x_pd_data_work(struct work_struct *work)
	{
	struct wm831x_ts *wm831x_ts =
	container_of(work, struct wm831x_ts, pd_data_work);

	if (wm831x_ts->pen_down) {
	enable_irq(wm831x_ts->data_irq);
	dev_dbg(wm831x_ts->wm831x->dev, "IRQ PD->DATA done\n");
	} else {
	enable_irq(wm831x_ts->pd_irq);
	dev_dbg(wm831x_ts->wm831x->dev, "IRQ DATA->PD done\n");
	}
	}

	static irqreturn_t wm831x_ts_data_irq(int irq, void *irq_data)
	{
	struct wm831x_ts *wm831x_ts = irq_data;
	struct wm831x *wm831x = wm831x_ts->wm831x;
	static int data_types[] = { ABS_X, ABS_Y, ABS_PRESSURE };
	u16 data[3];
	int count;
	int i, ret;

	if (wm831x_ts->pressure)
	count = 3;
	else
	count = 2;

	wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
	WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT);

	ret = wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count,
	data);
	if (ret != 0) {
	dev_err(wm831x->dev, "Failed to read touch data: %d\n",
	ret);
	return IRQ_NONE;
	}

	/*
	* We get a pen down reading on every reading, report pen up if any
	* individual reading does so.
	*/
	wm831x_ts->pen_down = true;
	for (i = 0; i < count; i++) {
	if (!(data[i] & WM831X_TCH_PD)) {
	wm831x_ts->pen_down = false;
	continue;
	}
	input_report_abs(wm831x_ts->input_dev, data_types[i],
	data[i] & WM831X_TCH_DATA_MASK);
	}

	if (!wm831x_ts->pen_down) {
	/* Switch from data to pen down */
	dev_dbg(wm831x->dev, "IRQ DATA->PD\n");

	disable_irq_nosync(wm831x_ts->data_irq);

	/* Don't need data any more */
	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
	WM831X_TCH_X_ENA \| WM831X_TCH_Y_ENA \|
	WM831X_TCH_Z_ENA, 0);

	/* Flush any final samples that arrived while reading */
	wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
	WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT);

	wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count, data);

	if (wm831x_ts->pressure)
	input_report_abs(wm831x_ts->input_dev,
	ABS_PRESSURE, 0);

	input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 0);

	schedule_work(&wm831x_ts->pd_data_work);
	} else {
	input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 1);
	}

	input_sync(wm831x_ts->input_dev);

	return IRQ_HANDLED;
	}

	static irqreturn_t wm831x_ts_pen_down_irq(int irq, void *irq_data)
	{
	struct wm831x_ts *wm831x_ts = irq_data;
	struct wm831x *wm831x = wm831x_ts->wm831x;
	int ena = 0;

	if (wm831x_ts->pen_down)
	return IRQ_HANDLED;

	disable_irq_nosync(wm831x_ts->pd_irq);

	/* Start collecting data */
	if (wm831x_ts->pressure)
	ena \|= WM831X_TCH_Z_ENA;

	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
	WM831X_TCH_X_ENA \| WM831X_TCH_Y_ENA \| WM831X_TCH_Z_ENA,
	WM831X_TCH_X_ENA \| WM831X_TCH_Y_ENA \| ena);

	wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
	WM831X_TCHPD_EINT, WM831X_TCHPD_EINT);

	wm831x_ts->pen_down = true;

	/* Switch from pen down to data */
	dev_dbg(wm831x->dev, "IRQ PD->DATA\n");
	schedule_work(&wm831x_ts->pd_data_work);

	return IRQ_HANDLED;
	}

	static int wm831x_ts_input_open(struct input_dev *idev)
	{
	struct wm831x_ts *wm831x_ts = input_get_drvdata(idev);
	struct wm831x *wm831x = wm831x_ts->wm831x;

	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
	WM831X_TCH_ENA \| WM831X_TCH_CVT_ENA \|
	WM831X_TCH_X_ENA \| WM831X_TCH_Y_ENA \|
	WM831X_TCH_Z_ENA, WM831X_TCH_ENA);

	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
	WM831X_TCH_CVT_ENA, WM831X_TCH_CVT_ENA);

	return 0;
	}

	static void wm831x_ts_input_close(struct input_dev *idev)
	{
	struct wm831x_ts *wm831x_ts = input_get_drvdata(idev);
	struct wm831x *wm831x = wm831x_ts->wm831x;

	/* Shut the controller down, disabling all other functionality too */
	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
	WM831X_TCH_ENA \| WM831X_TCH_X_ENA \|
	WM831X_TCH_Y_ENA \| WM831X_TCH_Z_ENA, 0);

	/* Make sure any pending IRQs are done, the above will prevent
	* new ones firing.
	*/
	synchronize_irq(wm831x_ts->data_irq);
	synchronize_irq(wm831x_ts->pd_irq);

	/* Make sure the IRQ completion work is quiesced */
	flush_work(&wm831x_ts->pd_data_work);

	/* If we ended up with the pen down then make sure we revert back
	* to pen detection state for the next time we start up.
	*/
	if (wm831x_ts->pen_down) {
	disable_irq(wm831x_ts->data_irq);
	enable_irq(wm831x_ts->pd_irq);
	wm831x_ts->pen_down = false;
	}
	}

	static int wm831x_ts_probe(struct platform_device *pdev)
	{
	struct wm831x_ts *wm831x_ts;
	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
	struct wm831x_pdata *core_pdata = dev_get_platdata(pdev->dev.parent);
	struct wm831x_touch_pdata *pdata = NULL;
	struct input_dev *input_dev;
	int error, irqf;

	if (core_pdata)
	pdata = core_pdata->touch;

	wm831x_ts = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_ts),
	GFP_KERNEL);
	input_dev = devm_input_allocate_device(&pdev->dev);
	if (!wm831x_ts \|\| !input_dev) {
	error = -ENOMEM;
	goto err_alloc;
	}

	wm831x_ts->wm831x = wm831x;
	wm831x_ts->input_dev = input_dev;
	INIT_WORK(&wm831x_ts->pd_data_work, wm831x_pd_data_work);

	/*
	* If we have a direct IRQ use it, otherwise use the interrupt
	* from the WM831x IRQ controller.
	*/
	wm831x_ts->data_irq = wm831x_irq(wm831x,
	platform_get_irq_byname(pdev,
	"TCHDATA"));
	if (pdata && pdata->data_irq)
	wm831x_ts->data_irq = pdata->data_irq;

	wm831x_ts->pd_irq = wm831x_irq(wm831x,
	platform_get_irq_byname(pdev, "TCHPD"));
	if (pdata && pdata->pd_irq)
	wm831x_ts->pd_irq = pdata->pd_irq;

	if (pdata)
	wm831x_ts->pressure = pdata->pressure;
	else
	wm831x_ts->pressure = true;

	/* Five wire touchscreens can't report pressure */
	if (pdata && pdata->fivewire) {
	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
	WM831X_TCH_5WIRE, WM831X_TCH_5WIRE);

	/* Pressure measurements are not possible for five wire mode */
	WARN_ON(pdata->pressure && pdata->fivewire);
	wm831x_ts->pressure = false;
	} else {
	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
	WM831X_TCH_5WIRE, 0);
	}

	if (pdata) {
	switch (pdata->isel) {
	default:
	dev_err(&pdev->dev, "Unsupported ISEL setting: %d\n",
	pdata->isel);
	/* Fall through */
	case 200:
	case 0:
	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
	WM831X_TCH_ISEL, 0);
	break;
	case 400:
	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
	WM831X_TCH_ISEL, WM831X_TCH_ISEL);
	break;
	}
	}

	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
	WM831X_TCH_PDONLY, 0);

	/* Default to 96 samples/sec */
	wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
	WM831X_TCH_RATE_MASK, 6);

	if (pdata && pdata->data_irqf)
	irqf = pdata->data_irqf;
	else
	irqf = IRQF_TRIGGER_HIGH;

	error = request_threaded_irq(wm831x_ts->data_irq,
	NULL, wm831x_ts_data_irq,
	irqf \| IRQF_ONESHOT,
	"Touchscreen data", wm831x_ts);
	if (error) {
	dev_err(&pdev->dev, "Failed to request data IRQ %d: %d\n",
	wm831x_ts->data_irq, error);
	goto err_alloc;
	}
	disable_irq(wm831x_ts->data_irq);

	if (pdata && pdata->pd_irqf)
	irqf = pdata->pd_irqf;
	else
	irqf = IRQF_TRIGGER_HIGH;

	error = request_threaded_irq(wm831x_ts->pd_irq,
	NULL, wm831x_ts_pen_down_irq,
	irqf \| IRQF_ONESHOT,
	"Touchscreen pen down", wm831x_ts);
	if (error) {
	dev_err(&pdev->dev, "Failed to request pen down IRQ %d: %d\n",
	wm831x_ts->pd_irq, error);
	goto err_data_irq;
	}

	/* set up touch configuration */
	input_dev->name = "WM831x touchscreen";
	input_dev->phys = "wm831x";
	input_dev->open = wm831x_ts_input_open;
	input_dev->close = wm831x_ts_input_close;

	__set_bit(EV_ABS, input_dev->evbit);
	__set_bit(EV_KEY, input_dev->evbit);
	__set_bit(BTN_TOUCH, input_dev->keybit);

	input_set_abs_params(input_dev, ABS_X, 0, 4095, 5, 0);
	input_set_abs_params(input_dev, ABS_Y, 0, 4095, 5, 0);
	if (wm831x_ts->pressure)
	input_set_abs_params(input_dev, ABS_PRESSURE, 0, 4095, 5, 0);

	input_set_drvdata(input_dev, wm831x_ts);
	input_dev->dev.parent = &pdev->dev;

	error = input_register_device(input_dev);
	if (error)
	goto err_pd_irq;

	platform_set_drvdata(pdev, wm831x_ts);
	return 0;

	err_pd_irq:
	free_irq(wm831x_ts->pd_irq, wm831x_ts);
	err_data_irq:
	free_irq(wm831x_ts->data_irq, wm831x_ts);
	err_alloc:

	return error;
	}

	static int wm831x_ts_remove(struct platform_device *pdev)
	{
	struct wm831x_ts *wm831x_ts = platform_get_drvdata(pdev);

	free_irq(wm831x_ts->pd_irq, wm831x_ts);
	free_irq(wm831x_ts->data_irq, wm831x_ts);

	return 0;
	}

	static struct platform_driver wm831x_ts_driver = {
	.driver = {
	.name = "wm831x-touch",
	},
	.probe = wm831x_ts_probe,
	.remove = wm831x_ts_remove,
	};
	module_platform_driver(wm831x_ts_driver);

	/* Module information */
	MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
	MODULE_DESCRIPTION("WM831x PMIC touchscreen driver");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("platform:wm831x-touch");