drivers/input/touchscreen/atmel-wm97xx.c - arm/linux-arm64-legacy - Git at Google

 /*
  * Atmel AT91 and AVR32 continuous touch screen driver for Wolfson WM97xx AC97
  * codecs.
  *
  * Copyright (C) 2008 - 2009 Atmel Corporation
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 as published by
  * the Free Software Foundation.
  */
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/delay.h>
 #include <linux/irq.h>
 #include <linux/interrupt.h>
 #include <linux/wm97xx.h>
 #include <linux/timer.h>
 #include <linux/gpio.h>
 #include <linux/io.h>
 #include <linux/slab.h>

 #define AC97C_ICA		0x10
 #define AC97C_CBRHR		0x30
 #define AC97C_CBSR		0x38
 #define AC97C_CBMR		0x3c
 #define AC97C_IER		0x54
 #define AC97C_IDR		0x58

 #define AC97C_RXRDY		(1 << 4)
 #define AC97C_OVRUN		(1 << 5)

 #define AC97C_CMR_SIZE_20	(0 << 16)
 #define AC97C_CMR_SIZE_18	(1 << 16)
 #define AC97C_CMR_SIZE_16	(2 << 16)
 #define AC97C_CMR_SIZE_10	(3 << 16)
 #define AC97C_CMR_CEM_LITTLE	(1 << 18)
 #define AC97C_CMR_CEM_BIG	(0 << 18)
 #define AC97C_CMR_CENA		(1 << 21)

 #define AC97C_INT_CBEVT		(1 << 4)

 #define AC97C_SR_CAEVT		(1 << 3)

 #define AC97C_CH_MASK(slot)						\
 	(0x7 << (3 * (slot - 3)))
 #define AC97C_CH_ASSIGN(slot, channel)					\
 	(AC97C_CHANNEL_##channel << (3 * (slot - 3)))
 #define AC97C_CHANNEL_NONE	0x0
 #define AC97C_CHANNEL_B		0x2

 #define ac97c_writel(chip, reg, val)			\
 	__raw_writel((val), (chip)->regs + AC97C_##reg)
 #define ac97c_readl(chip, reg)				\
 	__raw_readl((chip)->regs + AC97C_##reg)

 #ifdef CONFIG_CPU_AT32AP700X
 #define ATMEL_WM97XX_AC97C_IOMEM	(0xfff02800)
 #define ATMEL_WM97XX_AC97C_IRQ		(29)
 #define ATMEL_WM97XX_GPIO_DEFAULT	(32+16) /* Pin 16 on port B. */
 #else
 #error Unknown CPU, this driver only supports AT32AP700X CPUs.
 #endif

 struct continuous {
 	u16 id;    /* codec id */
 	u8 code;   /* continuous code */
 	u8 reads;  /* number of coord reads per read cycle */
 	u32 speed; /* number of coords per second */
 };

 #define WM_READS(sp) ((sp / HZ) + 1)

 static const struct continuous cinfo[] = {
 	{WM9705_ID2, 0, WM_READS(94), 94},
 	{WM9705_ID2, 1, WM_READS(188), 188},
 	{WM9705_ID2, 2, WM_READS(375), 375},
 	{WM9705_ID2, 3, WM_READS(750), 750},
 	{WM9712_ID2, 0, WM_READS(94), 94},
 	{WM9712_ID2, 1, WM_READS(188), 188},
 	{WM9712_ID2, 2, WM_READS(375), 375},
 	{WM9712_ID2, 3, WM_READS(750), 750},
 	{WM9713_ID2, 0, WM_READS(94), 94},
 	{WM9713_ID2, 1, WM_READS(120), 120},
 	{WM9713_ID2, 2, WM_READS(154), 154},
 	{WM9713_ID2, 3, WM_READS(188), 188},
 };

 /* Continuous speed index. */
 static int sp_idx;

 /*
  * Pen sampling frequency (Hz) in continuous mode.
  */
 static int cont_rate = 188;
 module_param(cont_rate, int, 0);
 MODULE_PARM_DESC(cont_rate, "Sampling rate in continuous mode (Hz)");

 /*
  * Pen down detection.
  *
  * This driver can either poll or use an interrupt to indicate a pen down
  * event. If the irq request fails then it will fall back to polling mode.
  */
 static int pen_int = 1;
 module_param(pen_int, int, 0);
 MODULE_PARM_DESC(pen_int, "Pen down detection (1 = interrupt, 0 = polling)");

 /*
  * Pressure readback.
  *
  * Set to 1 to read back pen down pressure.
  */
 static int pressure;
 module_param(pressure, int, 0);
 MODULE_PARM_DESC(pressure, "Pressure readback (1 = pressure, 0 = no pressure)");

 /*
  * AC97 touch data slot.
  *
  * Touch screen readback data ac97 slot.
  */
 static int ac97_touch_slot = 5;
 module_param(ac97_touch_slot, int, 0);
 MODULE_PARM_DESC(ac97_touch_slot, "Touch screen data slot AC97 number");

 /*
  * GPIO line number.
  *
  * Set to GPIO number where the signal from the WM97xx device is hooked up.
  */
 static int atmel_gpio_line = ATMEL_WM97XX_GPIO_DEFAULT;
 module_param(atmel_gpio_line, int, 0);
 MODULE_PARM_DESC(atmel_gpio_line, "GPIO line number connected to WM97xx");

 struct atmel_wm97xx {
 	struct wm97xx		*wm;
 	struct timer_list	pen_timer;
 	void __iomem		*regs;
 	unsigned long		ac97c_irq;
 	unsigned long		gpio_pen;
 	unsigned long		gpio_irq;
 	unsigned short		x;
 	unsigned short		y;
 };

 static irqreturn_t atmel_wm97xx_channel_b_interrupt(int irq, void *dev_id)
 {
 	struct atmel_wm97xx *atmel_wm97xx = dev_id;
 	struct wm97xx *wm = atmel_wm97xx->wm;
 	int status = ac97c_readl(atmel_wm97xx, CBSR);
 	irqreturn_t retval = IRQ_NONE;

 	if (status & AC97C_OVRUN) {
 		dev_dbg(&wm->touch_dev->dev, "AC97C overrun\n");
 		ac97c_readl(atmel_wm97xx, CBRHR);
 		retval = IRQ_HANDLED;
 	} else if (status & AC97C_RXRDY) {
 		u16 data;
 		u16 value;
 		u16 source;
 		u16 pen_down;

 		data = ac97c_readl(atmel_wm97xx, CBRHR);
 		value = data & 0x0fff;
 		source = data & WM97XX_ADCSEL_MASK;
 		pen_down = (data & WM97XX_PEN_DOWN) >> 8;

 		if (source == WM97XX_ADCSEL_X)
 			atmel_wm97xx->x = value;
 		if (source == WM97XX_ADCSEL_Y)
 			atmel_wm97xx->y = value;

 		if (!pressure && source == WM97XX_ADCSEL_Y) {
 			input_report_abs(wm->input_dev, ABS_X, atmel_wm97xx->x);
 			input_report_abs(wm->input_dev, ABS_Y, atmel_wm97xx->y);
 			input_report_key(wm->input_dev, BTN_TOUCH, pen_down);
 			input_sync(wm->input_dev);
 		} else if (pressure && source == WM97XX_ADCSEL_PRES) {
 			input_report_abs(wm->input_dev, ABS_X, atmel_wm97xx->x);
 			input_report_abs(wm->input_dev, ABS_Y, atmel_wm97xx->y);
 			input_report_abs(wm->input_dev, ABS_PRESSURE, value);
 			input_report_key(wm->input_dev, BTN_TOUCH, value);
 			input_sync(wm->input_dev);
 		}

 		retval = IRQ_HANDLED;
 	}

 	return retval;
 }

 static void atmel_wm97xx_acc_pen_up(struct wm97xx *wm)
 {
 	struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(wm->touch_dev);
 	struct input_dev *input_dev = wm->input_dev;
 	int pen_down = gpio_get_value(atmel_wm97xx->gpio_pen);

 	if (pen_down != 0) {
 		mod_timer(&atmel_wm97xx->pen_timer,
 			  jiffies + msecs_to_jiffies(1));
 	} else {
 		if (pressure)
 			input_report_abs(input_dev, ABS_PRESSURE, 0);
 		input_report_key(input_dev, BTN_TOUCH, 0);
 		input_sync(input_dev);
 	}
 }

 static void atmel_wm97xx_pen_timer(unsigned long data)
 {
 	atmel_wm97xx_acc_pen_up((struct wm97xx *)data);
 }

 static int atmel_wm97xx_acc_startup(struct wm97xx *wm)
 {
 	struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(wm->touch_dev);
 	int idx = 0;

 	if (wm->ac97 == NULL)
 		return -ENODEV;

 	for (idx = 0; idx < ARRAY_SIZE(cinfo); idx++) {
 		if (wm->id != cinfo[idx].id)
 			continue;

 		sp_idx = idx;

 		if (cont_rate <= cinfo[idx].speed)
 			break;
 	}

 	wm->acc_rate = cinfo[sp_idx].code;
 	wm->acc_slot = ac97_touch_slot;
 	dev_info(&wm->touch_dev->dev, "atmel accelerated touchscreen driver, "
 			"%d samples/sec\n", cinfo[sp_idx].speed);

 	if (pen_int) {
 		unsigned long reg;

 		wm->pen_irq = atmel_wm97xx->gpio_irq;

 		switch (wm->id) {
 		case WM9712_ID2: /* Fall through. */
 		case WM9713_ID2:
 			/*
 			 * Use GPIO 13 (PEN_DOWN) to assert GPIO line 3
 			 * (PENDOWN).
 			 */
 			wm97xx_config_gpio(wm, WM97XX_GPIO_13, WM97XX_GPIO_IN,
 					WM97XX_GPIO_POL_HIGH,
 					WM97XX_GPIO_STICKY,
 					WM97XX_GPIO_WAKE);
 			wm97xx_config_gpio(wm, WM97XX_GPIO_3, WM97XX_GPIO_OUT,
 					WM97XX_GPIO_POL_HIGH,
 					WM97XX_GPIO_NOTSTICKY,
 					WM97XX_GPIO_NOWAKE);
 		case WM9705_ID2: /* Fall through. */
 			/*
 			 * Enable touch data slot in AC97 controller channel B.
 			 */
 			reg = ac97c_readl(atmel_wm97xx, ICA);
 			reg &= ~AC97C_CH_MASK(wm->acc_slot);
 			reg |= AC97C_CH_ASSIGN(wm->acc_slot, B);
 			ac97c_writel(atmel_wm97xx, ICA, reg);

 			/*
 			 * Enable channel and interrupt for RXRDY and OVERRUN.
 			 */
 			ac97c_writel(atmel_wm97xx, CBMR, AC97C_CMR_CENA
 					| AC97C_CMR_CEM_BIG
 					| AC97C_CMR_SIZE_16
 					| AC97C_OVRUN
 					| AC97C_RXRDY);
 			/* Dummy read to empty RXRHR. */
 			ac97c_readl(atmel_wm97xx, CBRHR);
 			/*
 			 * Enable interrupt for channel B in the AC97
 			 * controller.
 			 */
 			ac97c_writel(atmel_wm97xx, IER, AC97C_INT_CBEVT);
 			break;
 		default:
 			dev_err(&wm->touch_dev->dev, "pen down irq not "
 					"supported on this device\n");
 			pen_int = 0;
 			break;
 		}
 	}

 	return 0;
 }

 static void atmel_wm97xx_acc_shutdown(struct wm97xx *wm)
 {
 	if (pen_int) {
 		struct atmel_wm97xx *atmel_wm97xx =
 			platform_get_drvdata(wm->touch_dev);
 		unsigned long ica;

 		switch (wm->id & 0xffff) {
 		case WM9705_ID2: /* Fall through. */
 		case WM9712_ID2: /* Fall through. */
 		case WM9713_ID2:
 			/* Disable slot and turn off channel B interrupts. */
 			ica = ac97c_readl(atmel_wm97xx, ICA);
 			ica &= ~AC97C_CH_MASK(wm->acc_slot);
 			ac97c_writel(atmel_wm97xx, ICA, ica);
 			ac97c_writel(atmel_wm97xx, IDR, AC97C_INT_CBEVT);
 			ac97c_writel(atmel_wm97xx, CBMR, 0);
 			wm->pen_irq = 0;
 			break;
 		default:
 			dev_err(&wm->touch_dev->dev, "unknown codec\n");
 			break;
 		}
 	}
 }

 static void atmel_wm97xx_irq_enable(struct wm97xx *wm, int enable)
 {
 	/* Intentionally left empty. */
 }

 static struct wm97xx_mach_ops atmel_mach_ops = {
 	.acc_enabled	= 1,
 	.acc_pen_up	= atmel_wm97xx_acc_pen_up,
 	.acc_startup	= atmel_wm97xx_acc_startup,
 	.acc_shutdown	= atmel_wm97xx_acc_shutdown,
 	.irq_enable	= atmel_wm97xx_irq_enable,
 	.irq_gpio	= WM97XX_GPIO_3,
 };

 static int __init atmel_wm97xx_probe(struct platform_device *pdev)
 {
 	struct wm97xx *wm = platform_get_drvdata(pdev);
 	struct atmel_wm97xx *atmel_wm97xx;
 	int ret;

 	atmel_wm97xx = kzalloc(sizeof(struct atmel_wm97xx), GFP_KERNEL);
 	if (!atmel_wm97xx) {
 		dev_dbg(&pdev->dev, "out of memory\n");
 		return -ENOMEM;
 	}

 	atmel_wm97xx->wm	= wm;
 	atmel_wm97xx->regs	= (void *)ATMEL_WM97XX_AC97C_IOMEM;
 	atmel_wm97xx->ac97c_irq	= ATMEL_WM97XX_AC97C_IRQ;
 	atmel_wm97xx->gpio_pen	= atmel_gpio_line;
 	atmel_wm97xx->gpio_irq	= gpio_to_irq(atmel_wm97xx->gpio_pen);

 	setup_timer(&atmel_wm97xx->pen_timer, atmel_wm97xx_pen_timer,
 			(unsigned long)wm);

 	ret = request_irq(atmel_wm97xx->ac97c_irq,
 			  atmel_wm97xx_channel_b_interrupt,
 			  IRQF_SHARED, "atmel-wm97xx-ch-b", atmel_wm97xx);
 	if (ret) {
 		dev_dbg(&pdev->dev, "could not request ac97c irq\n");
 		goto err;
 	}

 	platform_set_drvdata(pdev, atmel_wm97xx);

 	ret = wm97xx_register_mach_ops(wm, &atmel_mach_ops);
 	if (ret)
 		goto err_irq;

 	return ret;

 err_irq:
 	free_irq(atmel_wm97xx->ac97c_irq, atmel_wm97xx);
 err:
 	kfree(atmel_wm97xx);
 	return ret;
 }

 static int __exit atmel_wm97xx_remove(struct platform_device *pdev)
 {
 	struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(pdev);
 	struct wm97xx *wm = atmel_wm97xx->wm;

 	ac97c_writel(atmel_wm97xx, IDR, AC97C_INT_CBEVT);
 	free_irq(atmel_wm97xx->ac97c_irq, atmel_wm97xx);
 	del_timer_sync(&atmel_wm97xx->pen_timer);
 	wm97xx_unregister_mach_ops(wm);
 	kfree(atmel_wm97xx);

 	return 0;
 }

 #ifdef CONFIG_PM_SLEEP
 static int atmel_wm97xx_suspend(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(pdev);

 	ac97c_writel(atmel_wm97xx, IDR, AC97C_INT_CBEVT);
 	disable_irq(atmel_wm97xx->gpio_irq);
 	del_timer_sync(&atmel_wm97xx->pen_timer);

 	return 0;
 }

 static int atmel_wm97xx_resume(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(pdev);
 	struct wm97xx *wm = atmel_wm97xx->wm;

 	if (wm->input_dev->users) {
 		enable_irq(atmel_wm97xx->gpio_irq);
 		ac97c_writel(atmel_wm97xx, IER, AC97C_INT_CBEVT);
 	}

 	return 0;
 }
 #endif

 static SIMPLE_DEV_PM_OPS(atmel_wm97xx_pm_ops,
 			 atmel_wm97xx_suspend, atmel_wm97xx_resume);

 static struct platform_driver atmel_wm97xx_driver = {
 	.remove		= __exit_p(atmel_wm97xx_remove),
 	.driver		= {
 		.name	= "wm97xx-touch",
 		.owner	= THIS_MODULE,
 		.pm	= &atmel_wm97xx_pm_ops,
 	},
 };

 module_platform_driver_probe(atmel_wm97xx_driver, atmel_wm97xx_probe);

 MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
 MODULE_DESCRIPTION("wm97xx continuous touch driver for Atmel AT91 and AVR32");
 MODULE_LICENSE("GPL");
	/*
	* Atmel AT91 and AVR32 continuous touch screen driver for Wolfson WM97xx AC97
	* codecs.
	*
	* Copyright (C) 2008 - 2009 Atmel Corporation
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 as published by
	* the Free Software Foundation.
	*/
	#include <linux/module.h>
	#include <linux/moduleparam.h>
	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <linux/delay.h>
	#include <linux/irq.h>
	#include <linux/interrupt.h>
	#include <linux/wm97xx.h>
	#include <linux/timer.h>
	#include <linux/gpio.h>
	#include <linux/io.h>
	#include <linux/slab.h>

	#define AC97C_ICA 0x10
	#define AC97C_CBRHR 0x30
	#define AC97C_CBSR 0x38
	#define AC97C_CBMR 0x3c
	#define AC97C_IER 0x54
	#define AC97C_IDR 0x58

	#define AC97C_RXRDY (1 << 4)
	#define AC97C_OVRUN (1 << 5)

	#define AC97C_CMR_SIZE_20 (0 << 16)
	#define AC97C_CMR_SIZE_18 (1 << 16)
	#define AC97C_CMR_SIZE_16 (2 << 16)
	#define AC97C_CMR_SIZE_10 (3 << 16)
	#define AC97C_CMR_CEM_LITTLE (1 << 18)
	#define AC97C_CMR_CEM_BIG (0 << 18)
	#define AC97C_CMR_CENA (1 << 21)

	#define AC97C_INT_CBEVT (1 << 4)

	#define AC97C_SR_CAEVT (1 << 3)

	#define AC97C_CH_MASK(slot) \
	(0x7 << (3 * (slot - 3)))
	#define AC97C_CH_ASSIGN(slot, channel) \
	(AC97C_CHANNEL_##channel << (3 * (slot - 3)))
	#define AC97C_CHANNEL_NONE 0x0
	#define AC97C_CHANNEL_B 0x2

	#define ac97c_writel(chip, reg, val) \
	__raw_writel((val), (chip)->regs + AC97C_##reg)
	#define ac97c_readl(chip, reg) \
	__raw_readl((chip)->regs + AC97C_##reg)

	#ifdef CONFIG_CPU_AT32AP700X
	#define ATMEL_WM97XX_AC97C_IOMEM (0xfff02800)
	#define ATMEL_WM97XX_AC97C_IRQ (29)
	#define ATMEL_WM97XX_GPIO_DEFAULT (32+16) /* Pin 16 on port B. */
	#else
	#error Unknown CPU, this driver only supports AT32AP700X CPUs.
	#endif

	struct continuous {
	u16 id; /* codec id */
	u8 code; /* continuous code */
	u8 reads; /* number of coord reads per read cycle */
	u32 speed; /* number of coords per second */
	};

	#define WM_READS(sp) ((sp / HZ) + 1)

	static const struct continuous cinfo[] = {
	{WM9705_ID2, 0, WM_READS(94), 94},
	{WM9705_ID2, 1, WM_READS(188), 188},
	{WM9705_ID2, 2, WM_READS(375), 375},
	{WM9705_ID2, 3, WM_READS(750), 750},
	{WM9712_ID2, 0, WM_READS(94), 94},
	{WM9712_ID2, 1, WM_READS(188), 188},
	{WM9712_ID2, 2, WM_READS(375), 375},
	{WM9712_ID2, 3, WM_READS(750), 750},
	{WM9713_ID2, 0, WM_READS(94), 94},
	{WM9713_ID2, 1, WM_READS(120), 120},
	{WM9713_ID2, 2, WM_READS(154), 154},
	{WM9713_ID2, 3, WM_READS(188), 188},
	};

	/* Continuous speed index. */
	static int sp_idx;

	/*
	* Pen sampling frequency (Hz) in continuous mode.
	*/
	static int cont_rate = 188;
	module_param(cont_rate, int, 0);
	MODULE_PARM_DESC(cont_rate, "Sampling rate in continuous mode (Hz)");

	/*
	* Pen down detection.
	*
	* This driver can either poll or use an interrupt to indicate a pen down
	* event. If the irq request fails then it will fall back to polling mode.
	*/
	static int pen_int = 1;
	module_param(pen_int, int, 0);
	MODULE_PARM_DESC(pen_int, "Pen down detection (1 = interrupt, 0 = polling)");

	/*
	* Pressure readback.
	*
	* Set to 1 to read back pen down pressure.
	*/
	static int pressure;
	module_param(pressure, int, 0);
	MODULE_PARM_DESC(pressure, "Pressure readback (1 = pressure, 0 = no pressure)");

	/*
	* AC97 touch data slot.
	*
	* Touch screen readback data ac97 slot.
	*/
	static int ac97_touch_slot = 5;
	module_param(ac97_touch_slot, int, 0);
	MODULE_PARM_DESC(ac97_touch_slot, "Touch screen data slot AC97 number");

	/*
	* GPIO line number.
	*
	* Set to GPIO number where the signal from the WM97xx device is hooked up.
	*/
	static int atmel_gpio_line = ATMEL_WM97XX_GPIO_DEFAULT;
	module_param(atmel_gpio_line, int, 0);
	MODULE_PARM_DESC(atmel_gpio_line, "GPIO line number connected to WM97xx");

	struct atmel_wm97xx {
	struct wm97xx *wm;
	struct timer_list pen_timer;
	void __iomem *regs;
	unsigned long ac97c_irq;
	unsigned long gpio_pen;
	unsigned long gpio_irq;
	unsigned short x;
	unsigned short y;
	};

	static irqreturn_t atmel_wm97xx_channel_b_interrupt(int irq, void *dev_id)
	{
	struct atmel_wm97xx *atmel_wm97xx = dev_id;
	struct wm97xx *wm = atmel_wm97xx->wm;
	int status = ac97c_readl(atmel_wm97xx, CBSR);
	irqreturn_t retval = IRQ_NONE;

	if (status & AC97C_OVRUN) {
	dev_dbg(&wm->touch_dev->dev, "AC97C overrun\n");
	ac97c_readl(atmel_wm97xx, CBRHR);
	retval = IRQ_HANDLED;
	} else if (status & AC97C_RXRDY) {
	u16 data;
	u16 value;
	u16 source;
	u16 pen_down;

	data = ac97c_readl(atmel_wm97xx, CBRHR);
	value = data & 0x0fff;
	source = data & WM97XX_ADCSEL_MASK;
	pen_down = (data & WM97XX_PEN_DOWN) >> 8;

	if (source == WM97XX_ADCSEL_X)
	atmel_wm97xx->x = value;
	if (source == WM97XX_ADCSEL_Y)
	atmel_wm97xx->y = value;

	if (!pressure && source == WM97XX_ADCSEL_Y) {
	input_report_abs(wm->input_dev, ABS_X, atmel_wm97xx->x);
	input_report_abs(wm->input_dev, ABS_Y, atmel_wm97xx->y);
	input_report_key(wm->input_dev, BTN_TOUCH, pen_down);
	input_sync(wm->input_dev);
	} else if (pressure && source == WM97XX_ADCSEL_PRES) {
	input_report_abs(wm->input_dev, ABS_X, atmel_wm97xx->x);
	input_report_abs(wm->input_dev, ABS_Y, atmel_wm97xx->y);
	input_report_abs(wm->input_dev, ABS_PRESSURE, value);
	input_report_key(wm->input_dev, BTN_TOUCH, value);
	input_sync(wm->input_dev);
	}

	retval = IRQ_HANDLED;
	}

	return retval;
	}

	static void atmel_wm97xx_acc_pen_up(struct wm97xx *wm)
	{
	struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(wm->touch_dev);
	struct input_dev *input_dev = wm->input_dev;
	int pen_down = gpio_get_value(atmel_wm97xx->gpio_pen);

	if (pen_down != 0) {
	mod_timer(&atmel_wm97xx->pen_timer,
	jiffies + msecs_to_jiffies(1));
	} else {
	if (pressure)
	input_report_abs(input_dev, ABS_PRESSURE, 0);
	input_report_key(input_dev, BTN_TOUCH, 0);
	input_sync(input_dev);
	}
	}

	static void atmel_wm97xx_pen_timer(unsigned long data)
	{
	atmel_wm97xx_acc_pen_up((struct wm97xx *)data);
	}

	static int atmel_wm97xx_acc_startup(struct wm97xx *wm)
	{
	struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(wm->touch_dev);
	int idx = 0;

	if (wm->ac97 == NULL)
	return -ENODEV;

	for (idx = 0; idx < ARRAY_SIZE(cinfo); idx++) {
	if (wm->id != cinfo[idx].id)
	continue;

	sp_idx = idx;

	if (cont_rate <= cinfo[idx].speed)
	break;
	}

	wm->acc_rate = cinfo[sp_idx].code;
	wm->acc_slot = ac97_touch_slot;
	dev_info(&wm->touch_dev->dev, "atmel accelerated touchscreen driver, "
	"%d samples/sec\n", cinfo[sp_idx].speed);

	if (pen_int) {
	unsigned long reg;

	wm->pen_irq = atmel_wm97xx->gpio_irq;

	switch (wm->id) {
	case WM9712_ID2: /* Fall through. */
	case WM9713_ID2:
	/*
	* Use GPIO 13 (PEN_DOWN) to assert GPIO line 3
	* (PENDOWN).
	*/
	wm97xx_config_gpio(wm, WM97XX_GPIO_13, WM97XX_GPIO_IN,
	WM97XX_GPIO_POL_HIGH,
	WM97XX_GPIO_STICKY,
	WM97XX_GPIO_WAKE);
	wm97xx_config_gpio(wm, WM97XX_GPIO_3, WM97XX_GPIO_OUT,
	WM97XX_GPIO_POL_HIGH,
	WM97XX_GPIO_NOTSTICKY,
	WM97XX_GPIO_NOWAKE);
	case WM9705_ID2: /* Fall through. */
	/*
	* Enable touch data slot in AC97 controller channel B.
	*/
	reg = ac97c_readl(atmel_wm97xx, ICA);
	reg &= ~AC97C_CH_MASK(wm->acc_slot);
	reg \|= AC97C_CH_ASSIGN(wm->acc_slot, B);
	ac97c_writel(atmel_wm97xx, ICA, reg);

	/*
	* Enable channel and interrupt for RXRDY and OVERRUN.
	*/
	ac97c_writel(atmel_wm97xx, CBMR, AC97C_CMR_CENA
	\| AC97C_CMR_CEM_BIG
	\| AC97C_CMR_SIZE_16
	\| AC97C_OVRUN
	\| AC97C_RXRDY);
	/* Dummy read to empty RXRHR. */
	ac97c_readl(atmel_wm97xx, CBRHR);
	/*
	* Enable interrupt for channel B in the AC97
	* controller.
	*/
	ac97c_writel(atmel_wm97xx, IER, AC97C_INT_CBEVT);
	break;
	default:
	dev_err(&wm->touch_dev->dev, "pen down irq not "
	"supported on this device\n");
	pen_int = 0;
	break;
	}
	}

	return 0;
	}

	static void atmel_wm97xx_acc_shutdown(struct wm97xx *wm)
	{
	if (pen_int) {
	struct atmel_wm97xx *atmel_wm97xx =
	platform_get_drvdata(wm->touch_dev);
	unsigned long ica;

	switch (wm->id & 0xffff) {
	case WM9705_ID2: /* Fall through. */
	case WM9712_ID2: /* Fall through. */
	case WM9713_ID2:
	/* Disable slot and turn off channel B interrupts. */
	ica = ac97c_readl(atmel_wm97xx, ICA);
	ica &= ~AC97C_CH_MASK(wm->acc_slot);
	ac97c_writel(atmel_wm97xx, ICA, ica);
	ac97c_writel(atmel_wm97xx, IDR, AC97C_INT_CBEVT);
	ac97c_writel(atmel_wm97xx, CBMR, 0);
	wm->pen_irq = 0;
	break;
	default:
	dev_err(&wm->touch_dev->dev, "unknown codec\n");
	break;
	}
	}
	}

	static void atmel_wm97xx_irq_enable(struct wm97xx *wm, int enable)
	{
	/* Intentionally left empty. */
	}

	static struct wm97xx_mach_ops atmel_mach_ops = {
	.acc_enabled = 1,
	.acc_pen_up = atmel_wm97xx_acc_pen_up,
	.acc_startup = atmel_wm97xx_acc_startup,
	.acc_shutdown = atmel_wm97xx_acc_shutdown,
	.irq_enable = atmel_wm97xx_irq_enable,
	.irq_gpio = WM97XX_GPIO_3,
	};

	static int __init atmel_wm97xx_probe(struct platform_device *pdev)
	{
	struct wm97xx *wm = platform_get_drvdata(pdev);
	struct atmel_wm97xx *atmel_wm97xx;
	int ret;

	atmel_wm97xx = kzalloc(sizeof(struct atmel_wm97xx), GFP_KERNEL);
	if (!atmel_wm97xx) {
	dev_dbg(&pdev->dev, "out of memory\n");
	return -ENOMEM;
	}

	atmel_wm97xx->wm = wm;
	atmel_wm97xx->regs = (void *)ATMEL_WM97XX_AC97C_IOMEM;
	atmel_wm97xx->ac97c_irq = ATMEL_WM97XX_AC97C_IRQ;
	atmel_wm97xx->gpio_pen = atmel_gpio_line;
	atmel_wm97xx->gpio_irq = gpio_to_irq(atmel_wm97xx->gpio_pen);

	setup_timer(&atmel_wm97xx->pen_timer, atmel_wm97xx_pen_timer,
	(unsigned long)wm);

	ret = request_irq(atmel_wm97xx->ac97c_irq,
	atmel_wm97xx_channel_b_interrupt,
	IRQF_SHARED, "atmel-wm97xx-ch-b", atmel_wm97xx);
	if (ret) {
	dev_dbg(&pdev->dev, "could not request ac97c irq\n");
	goto err;
	}

	platform_set_drvdata(pdev, atmel_wm97xx);

	ret = wm97xx_register_mach_ops(wm, &atmel_mach_ops);
	if (ret)
	goto err_irq;

	return ret;

	err_irq:
	free_irq(atmel_wm97xx->ac97c_irq, atmel_wm97xx);
	err:
	kfree(atmel_wm97xx);
	return ret;
	}

	static int __exit atmel_wm97xx_remove(struct platform_device *pdev)
	{
	struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(pdev);
	struct wm97xx *wm = atmel_wm97xx->wm;

	ac97c_writel(atmel_wm97xx, IDR, AC97C_INT_CBEVT);
	free_irq(atmel_wm97xx->ac97c_irq, atmel_wm97xx);
	del_timer_sync(&atmel_wm97xx->pen_timer);
	wm97xx_unregister_mach_ops(wm);
	kfree(atmel_wm97xx);

	return 0;
	}

	#ifdef CONFIG_PM_SLEEP
	static int atmel_wm97xx_suspend(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(pdev);

	ac97c_writel(atmel_wm97xx, IDR, AC97C_INT_CBEVT);
	disable_irq(atmel_wm97xx->gpio_irq);
	del_timer_sync(&atmel_wm97xx->pen_timer);

	return 0;
	}

	static int atmel_wm97xx_resume(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(pdev);
	struct wm97xx *wm = atmel_wm97xx->wm;

	if (wm->input_dev->users) {
	enable_irq(atmel_wm97xx->gpio_irq);
	ac97c_writel(atmel_wm97xx, IER, AC97C_INT_CBEVT);
	}

	return 0;
	}
	#endif

	static SIMPLE_DEV_PM_OPS(atmel_wm97xx_pm_ops,
	atmel_wm97xx_suspend, atmel_wm97xx_resume);

	static struct platform_driver atmel_wm97xx_driver = {
	.remove = __exit_p(atmel_wm97xx_remove),
	.driver = {
	.name = "wm97xx-touch",
	.owner = THIS_MODULE,
	.pm = &atmel_wm97xx_pm_ops,
	},
	};

	module_platform_driver_probe(atmel_wm97xx_driver, atmel_wm97xx_probe);

	MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
	MODULE_DESCRIPTION("wm97xx continuous touch driver for Atmel AT91 and AVR32");
	MODULE_LICENSE("GPL");