[linux-2.6-block.git] / drivers / input / touchscreen / wm9712.c

/*
 * wm9712.c  --  Codec driver for Wolfson WM9712 AC97 Codecs.
 *
 * Copyright 2003, 2004, 2005, 2006, 2007 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.
 *
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/input.h>
#include <linux/delay.h>
#include <linux/bitops.h>
#include <linux/wm97xx.h>

#define TS_NAME			"wm97xx"
#define WM9712_VERSION		"1.00"
#define DEFAULT_PRESSURE	0xb0c0

/*
 * Module parameters
 */

/*
 * Set internal pull up for pen detect.
 *
 * Pull up is in the range 1.02k (least sensitive) to 64k (most sensitive)
 * i.e. pull up resistance = 64k Ohms / rpu.
 *
 * Adjust this value if you are having problems with pen detect not
 * detecting any down event.
 */
static int rpu = 8;
module_param(rpu, int, 0);
MODULE_PARM_DESC(rpu, "Set internal pull up resitor for pen detect.");

/*
 * Set current used for pressure measurement.
 *
 * Set pil = 2 to use 400uA
 *     pil = 1 to use 200uA and
 *     pil = 0 to disable pressure measurement.
 *
 * This is used to increase the range of values returned by the adc
 * when measureing touchpanel pressure.
 */
static int pil;
module_param(pil, int, 0);
MODULE_PARM_DESC(pil, "Set current used for pressure measurement.");

/*
 * Set threshold for pressure measurement.
 *
 * Pen down pressure below threshold is ignored.
 */
static int pressure = DEFAULT_PRESSURE & 0xfff;
module_param(pressure, int, 0);
MODULE_PARM_DESC(pressure, "Set threshold for pressure measurement.");

/*
 * Set adc sample delay.
 *
 * For accurate touchpanel measurements, some settling time may be
 * required between the switch matrix applying a voltage across the
 * touchpanel plate and the ADC sampling the signal.
 *
 * This delay can be set by setting delay = n, where n is the array
 * position of the delay in the array delay_table below.
 * Long delays > 1ms are supported for completeness, but are not
 * recommended.
 */
static int delay = 3;
module_param(delay, int, 0);
MODULE_PARM_DESC(delay, "Set adc sample delay.");

/*
 * Set five_wire = 1 to use a 5 wire touchscreen.
 *
 * NOTE: Five wire mode does not allow for readback of pressure.
 */
static int five_wire;
module_param(five_wire, int, 0);
MODULE_PARM_DESC(five_wire, "Set to '1' to use 5-wire touchscreen.");

/*
 * Set adc mask function.
 *
 * Sources of glitch noise, such as signals driving an LCD display, may feed
 * through to the touch screen plates and affect measurement accuracy. In
 * order to minimise this, a signal may be applied to the MASK pin to delay or
 * synchronise the sampling.
 *
 * 0 = No delay or sync
 * 1 = High on pin stops conversions
 * 2 = Edge triggered, edge on pin delays conversion by delay param (above)
 * 3 = Edge triggered, edge on pin starts conversion after delay param
 */
static int mask;
module_param(mask, int, 0);
MODULE_PARM_DESC(mask, "Set adc mask function.");

/*
 * Coordinate Polling Enable.
 *
 * Set to 1 to enable coordinate polling. e.g. x,y[,p] is sampled together
 * for every poll.
 */
static int coord;
module_param(coord, int, 0);
MODULE_PARM_DESC(coord, "Polling coordinate mode");

/*
 * ADC sample delay times in uS
 */
static const int delay_table[] = {
	21,    /* 1 AC97 Link frames */
	42,    /* 2 */
	84,    /* 4 */
	167,   /* 8 */
	333,   /* 16 */
	667,   /* 32 */
	1000,  /* 48 */
	1333,  /* 64 */
	2000,  /* 96 */
	2667,  /* 128 */
	3333,  /* 160 */
	4000,  /* 192 */
	4667,  /* 224 */
	5333,  /* 256 */
	6000,  /* 288 */
	0      /* No delay, switch matrix always on */
};

/*
 * Delay after issuing a POLL command.
 *
 * The delay is 3 AC97 link frames + the touchpanel settling delay
 */
static inline void poll_delay(int d)
{
	udelay(3 * AC97_LINK_FRAME + delay_table[d]);
}

/*
 * set up the physical settings of the WM9712
 */
static void wm9712_phy_init(struct wm97xx *wm)
{
	u16 dig1 = 0;
	u16 dig2 = WM97XX_RPR | WM9712_RPU(1);

	/* WM9712 rpu */
	if (rpu) {
		dig2 &= 0xffc0;
		dig2 |= WM9712_RPU(rpu);
		dev_dbg(wm->dev, "setting pen detect pull-up to %d Ohms",
			64000 / rpu);
	}

	/* WM9712 five wire */
	if (five_wire) {
		dig2 |= WM9712_45W;
		dev_dbg(wm->dev, "setting 5-wire touchscreen mode.");

		if (pil) {
			dev_warn(wm->dev, "pressure measurement is not "
				 "supported in 5-wire mode\n");
			pil = 0;
		}
	}

	/* touchpanel pressure current*/
	if (pil == 2) {
		dig2 |= WM9712_PIL;
		dev_dbg(wm->dev,
			"setting pressure measurement current to 400uA.");
	} else if (pil)
		dev_dbg(wm->dev,
			"setting pressure measurement current to 200uA.");
	if (!pil)
		pressure = 0;

	/* polling mode sample settling delay */
	if (delay < 0 || delay > 15) {
		dev_dbg(wm->dev, "supplied delay out of range.");
		delay = 4;
	}
	dig1 &= 0xff0f;
	dig1 |= WM97XX_DELAY(delay);
	dev_dbg(wm->dev, "setting adc sample delay to %d u Secs.",
		delay_table[delay]);

	/* mask */
	dig2 |= ((mask & 0x3) << 6);
	if (mask) {
		u16 reg;
		/* Set GPIO4 as Mask Pin*/
		reg = wm97xx_reg_read(wm, AC97_MISC_AFE);
		wm97xx_reg_write(wm, AC97_MISC_AFE, reg | WM97XX_GPIO_4);
		reg = wm97xx_reg_read(wm, AC97_GPIO_CFG);
		wm97xx_reg_write(wm, AC97_GPIO_CFG, reg | WM97XX_GPIO_4);
	}

	/* wait - coord mode */
	if (coord)
		dig2 |= WM9712_WAIT;

	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, dig1);
	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, dig2);
}

static void wm9712_dig_enable(struct wm97xx *wm, int enable)
{
	u16 dig2 = wm->dig[2];

	if (enable) {
		wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2,
				 dig2 | WM97XX_PRP_DET_DIG);
		wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); /* dummy read */
	} else
		wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2,
				 dig2 & ~WM97XX_PRP_DET_DIG);
}

static void wm9712_aux_prepare(struct wm97xx *wm)
{
	memcpy(wm->dig_save, wm->dig, sizeof(wm->dig));
	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, 0);
	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, WM97XX_PRP_DET_DIG);
}

static void wm9712_dig_restore(struct wm97xx *wm)
{
	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, wm->dig_save[1]);
	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, wm->dig_save[2]);
}

static inline int is_pden(struct wm97xx *wm)
{
	return wm->dig[2] & WM9712_PDEN;
}

/*
 * Read a sample from the WM9712 adc in polling mode.
 */
static int wm9712_poll_sample(struct wm97xx *wm, int adcsel, int *sample)
{
	int timeout = 5 * delay;

	if (!wm->pen_probably_down) {
		u16 data = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
		if (!(data & WM97XX_PEN_DOWN))
			return RC_PENUP;
		wm->pen_probably_down = 1;
	}

	/* set up digitiser */
	if (adcsel & 0x8000)
		adcsel = ((adcsel & 0x7fff) + 3) << 12;

	if (wm->mach_ops && wm->mach_ops->pre_sample)
		wm->mach_ops->pre_sample(adcsel);
	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1,
			 adcsel | WM97XX_POLL | WM97XX_DELAY(delay));

	/* wait 3 AC97 time slots + delay for conversion */
	poll_delay(delay);

	/* wait for POLL to go low */
	while ((wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER1) & WM97XX_POLL)
	       && timeout) {
		udelay(AC97_LINK_FRAME);
		timeout--;
	}

	if (timeout <= 0) {
		/* If PDEN is set, we can get a timeout when pen goes up */
		if (is_pden(wm))
			wm->pen_probably_down = 0;
		else
			dev_dbg(wm->dev, "adc sample timeout");
		return RC_PENUP;
	}

	*sample = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
	if (wm->mach_ops && wm->mach_ops->post_sample)
		wm->mach_ops->post_sample(adcsel);

	/* check we have correct sample */
	if ((*sample & WM97XX_ADCSEL_MASK) != adcsel) {
		dev_dbg(wm->dev, "adc wrong sample, read %x got %x", adcsel,
		*sample & WM97XX_ADCSEL_MASK);
		return RC_PENUP;
	}

	if (!(*sample & WM97XX_PEN_DOWN)) {
		wm->pen_probably_down = 0;
		return RC_PENUP;
	}

	return RC_VALID;
}

/*
 * Read a coord from the WM9712 adc in polling mode.
 */
static int wm9712_poll_coord(struct wm97xx *wm, struct wm97xx_data *data)
{
	int timeout = 5 * delay;

	if (!wm->pen_probably_down) {
		u16 data_rd = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
		if (!(data_rd & WM97XX_PEN_DOWN))
			return RC_PENUP;
		wm->pen_probably_down = 1;
	}

	/* set up digitiser */
	if (wm->mach_ops && wm->mach_ops->pre_sample)
		wm->mach_ops->pre_sample(WM97XX_ADCSEL_X | WM97XX_ADCSEL_Y);

	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1,
		WM97XX_COO | WM97XX_POLL | WM97XX_DELAY(delay));

	/* wait 3 AC97 time slots + delay for conversion and read x */
	poll_delay(delay);
	data->x = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
	/* wait for POLL to go low */
	while ((wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER1) & WM97XX_POLL)
	       && timeout) {
		udelay(AC97_LINK_FRAME);
		timeout--;
	}

	if (timeout <= 0) {
		/* If PDEN is set, we can get a timeout when pen goes up */
		if (is_pden(wm))
			wm->pen_probably_down = 0;
		else
			dev_dbg(wm->dev, "adc sample timeout");
		return RC_PENUP;
	}

	/* read back y data */
	data->y = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
	if (pil)
		data->p = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
	else
		data->p = DEFAULT_PRESSURE;

	if (wm->mach_ops && wm->mach_ops->post_sample)
		wm->mach_ops->post_sample(WM97XX_ADCSEL_X | WM97XX_ADCSEL_Y);

	/* check we have correct sample */
	if (!(data->x & WM97XX_ADCSEL_X) || !(data->y & WM97XX_ADCSEL_Y))
		goto err;
	if (pil && !(data->p & WM97XX_ADCSEL_PRES))
		goto err;

	if (!(data->x & WM97XX_PEN_DOWN) || !(data->y & WM97XX_PEN_DOWN)) {
		wm->pen_probably_down = 0;
		return RC_PENUP;
	}
	return RC_VALID;
err:
	return 0;
}

/*
 * Sample the WM9712 touchscreen in polling mode
 */
static int wm9712_poll_touch(struct wm97xx *wm, struct wm97xx_data *data)
{
	int rc;

	if (coord) {
		rc = wm9712_poll_coord(wm, data);
		if (rc != RC_VALID)
			return rc;
	} else {
		rc = wm9712_poll_sample(wm, WM97XX_ADCSEL_X, &data->x);
		if (rc != RC_VALID)
			return rc;

		rc = wm9712_poll_sample(wm, WM97XX_ADCSEL_Y, &data->y);
		if (rc != RC_VALID)
			return rc;

		if (pil && !five_wire) {
			rc = wm9712_poll_sample(wm, WM97XX_ADCSEL_PRES,
						&data->p);
			if (rc != RC_VALID)
				return rc;
		} else
			data->p = DEFAULT_PRESSURE;
	}
	return RC_VALID;
}

/*
 * Enable WM9712 continuous mode, i.e. touch data is streamed across
 * an AC97 slot
 */
static int wm9712_acc_enable(struct wm97xx *wm, int enable)
{
	u16 dig1, dig2;
	int ret = 0;

	dig1 = wm->dig[1];
	dig2 = wm->dig[2];

	if (enable) {
		/* continous mode */
		if (wm->mach_ops->acc_startup) {
			ret = wm->mach_ops->acc_startup(wm);
			if (ret < 0)
				return ret;
		}
		dig1 &= ~(WM97XX_CM_RATE_MASK | WM97XX_ADCSEL_MASK |
			WM97XX_DELAY_MASK | WM97XX_SLT_MASK);
		dig1 |= WM97XX_CTC | WM97XX_COO | WM97XX_SLEN |
			WM97XX_DELAY(delay) |
			WM97XX_SLT(wm->acc_slot) |
			WM97XX_RATE(wm->acc_rate);
		if (pil)
			dig1 |= WM97XX_ADCSEL_PRES;
		dig2 |= WM9712_PDEN;
	} else {
		dig1 &= ~(WM97XX_CTC | WM97XX_COO | WM97XX_SLEN);
		dig2 &= ~WM9712_PDEN;
		if (wm->mach_ops->acc_shutdown)
			wm->mach_ops->acc_shutdown(wm);
	}

	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, dig1);
	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, dig2);

	return 0;
}

struct wm97xx_codec_drv wm9712_codec = {
	.id = WM9712_ID2,
	.name = "wm9712",
	.poll_sample = wm9712_poll_sample,
	.poll_touch = wm9712_poll_touch,
	.acc_enable = wm9712_acc_enable,
	.phy_init = wm9712_phy_init,
	.dig_enable = wm9712_dig_enable,
	.dig_restore = wm9712_dig_restore,
	.aux_prepare = wm9712_aux_prepare,
};
EXPORT_SYMBOL_GPL(wm9712_codec);

/* Module information */
MODULE_AUTHOR("Liam Girdwood <liam.girdwood@wolfsonmicro.com>");
MODULE_DESCRIPTION("WM9712 Touch Screen Driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
de22b9ef MB	1	/*
	2	* wm9712.c -- Codec driver for Wolfson WM9712 AC97 Codecs.
	3	*
	4	* Copyright 2003, 2004, 2005, 2006, 2007 Wolfson Microelectronics PLC.
	5	* Author: Liam Girdwood
	6	* liam.girdwood@wolfsonmicro.com or linux@wolfsonmicro.com
	7	* Parts Copyright : Ian Molton <spyro@f2s.com>
	8	* Andrew Zabolotny <zap@homelink.ru>
	9	* Russell King <rmk@arm.linux.org.uk>
	10	*
	11	* This program is free software; you can redistribute it and/or modify it
	12	* under the terms of the GNU General Public License as published by the
	13	* Free Software Foundation; either version 2 of the License, or (at your
	14	* option) any later version.
	15	*
	16	*/
	17
	18	#include <linux/module.h>
	19	#include <linux/moduleparam.h>
de22b9ef MB	20	#include <linux/kernel.h>
	21	#include <linux/input.h>
	22	#include <linux/delay.h>
	23	#include <linux/bitops.h>
	24	#include <linux/wm97xx.h>
	25
	26	#define TS_NAME "wm97xx"
	27	#define WM9712_VERSION "1.00"
	28	#define DEFAULT_PRESSURE 0xb0c0
	29
	30	/*
	31	* Module parameters
	32	*/
	33
	34	/*
	35	* Set internal pull up for pen detect.
	36	*
	37	* Pull up is in the range 1.02k (least sensitive) to 64k (most sensitive)
	38	* i.e. pull up resistance = 64k Ohms / rpu.
	39	*
	40	* Adjust this value if you are having problems with pen detect not
	41	* detecting any down event.
	42	*/
	43	static int rpu = 8;
	44	module_param(rpu, int, 0);
	45	MODULE_PARM_DESC(rpu, "Set internal pull up resitor for pen detect.");
	46
	47	/*
	48	* Set current used for pressure measurement.
	49	*
	50	* Set pil = 2 to use 400uA
	51	* pil = 1 to use 200uA and
	52	* pil = 0 to disable pressure measurement.
	53	*
	54	* This is used to increase the range of values returned by the adc
	55	* when measureing touchpanel pressure.
	56	*/
	57	static int pil;
	58	module_param(pil, int, 0);
	59	MODULE_PARM_DESC(pil, "Set current used for pressure measurement.");
	60
	61	/*
	62	* Set threshold for pressure measurement.
	63	*
	64	* Pen down pressure below threshold is ignored.
	65	*/
	66	static int pressure = DEFAULT_PRESSURE & 0xfff;
	67	module_param(pressure, int, 0);
	68	MODULE_PARM_DESC(pressure, "Set threshold for pressure measurement.");
	69
	70	/*
	71	* Set adc sample delay.
	72	*
	73	* For accurate touchpanel measurements, some settling time may be
	74	* required between the switch matrix applying a voltage across the
	75	* touchpanel plate and the ADC sampling the signal.
	76	*
	77	* This delay can be set by setting delay = n, where n is the array
	78	* position of the delay in the array delay_table below.
	79	* Long delays > 1ms are supported for completeness, but are not
	80	* recommended.
	81	*/
	82	static int delay = 3;
	83	module_param(delay, int, 0);
84	MODULE_PARM_DESC(delay, "Set adc sample delay.");
85
86	/*
87	* Set five_wire = 1 to use a 5 wire touchscreen.
88	*
89	* NOTE: Five wire mode does not allow for readback of pressure.
90	*/
91	static int five_wire;
92	module_param(five_wire, int, 0);
93	MODULE_PARM_DESC(five_wire, "Set to '1' to use 5-wire touchscreen.");
94
95	/*
96	* Set adc mask function.
97	*
98	* Sources of glitch noise, such as signals driving an LCD display, may feed
99	* through to the touch screen plates and affect measurement accuracy. In
100	* order to minimise this, a signal may be applied to the MASK pin to delay or
101	* synchronise the sampling.
102	*
103	* 0 = No delay or sync
104	* 1 = High on pin stops conversions
105	* 2 = Edge triggered, edge on pin delays conversion by delay param (above)
106	* 3 = Edge triggered, edge on pin starts conversion after delay param
107	*/
108	static int mask;
109	module_param(mask, int, 0);
110	MODULE_PARM_DESC(mask, "Set adc mask function.");
111
112	/*
113	* Coordinate Polling Enable.
114	*
115	* Set to 1 to enable coordinate polling. e.g. x,y[,p] is sampled together
116	* for every poll.
117	*/
118	static int coord;
119	module_param(coord, int, 0);
120	MODULE_PARM_DESC(coord, "Polling coordinate mode");
121
122	/*
123	* ADC sample delay times in uS
124	*/
125	static const int delay_table[] = {
126	21, /* 1 AC97 Link frames */
127	42, /* 2 */
128	84, /* 4 */
129	167, /* 8 */
130	333, /* 16 */
131	667, /* 32 */
132	1000, /* 48 */
133	1333, /* 64 */
134	2000, /* 96 */
135	2667, /* 128 */
136	3333, /* 160 */
137	4000, /* 192 */
138	4667, /* 224 */
139	5333, /* 256 */
140	6000, /* 288 */
141	0 /* No delay, switch matrix always on */
142	};
143
144	/*
145	* Delay after issuing a POLL command.
146	*
147	* The delay is 3 AC97 link frames + the touchpanel settling delay
148	*/
149	static inline void poll_delay(int d)
150	{
151	udelay(3 * AC97_LINK_FRAME + delay_table[d]);
152	}
153
154	/*
155	* set up the physical settings of the WM9712
156	*/
157	static void wm9712_phy_init(struct wm97xx *wm)
158	{
159	u16 dig1 = 0;
160	u16 dig2 = WM97XX_RPR \| WM9712_RPU(1);
161
162	/* WM9712 rpu */
163	if (rpu) {
164	dig2 &= 0xffc0;
165	dig2 \|= WM9712_RPU(rpu);
166	dev_dbg(wm->dev, "setting pen detect pull-up to %d Ohms",
167	64000 / rpu);
168	}
169
8a65c02f MB	170	/* WM9712 five wire */
	171	if (five_wire) {
	172	dig2 \|= WM9712_45W;
	173	dev_dbg(wm->dev, "setting 5-wire touchscreen mode.");
	174
	175	if (pil) {
	176	dev_warn(wm->dev, "pressure measurement is not "
	177	"supported in 5-wire mode\n");
	178	pil = 0;
	179	}
	180	}
	181
de22b9ef MB	182	/* touchpanel pressure current*/
	183	if (pil == 2) {
	184	dig2 \|= WM9712_PIL;
	185	dev_dbg(wm->dev,
	186	"setting pressure measurement current to 400uA.");
	187	} else if (pil)
	188	dev_dbg(wm->dev,
	189	"setting pressure measurement current to 200uA.");
	190	if (!pil)
	191	pressure = 0;
	192
de22b9ef MB	193	/* polling mode sample settling delay */
	194	if (delay < 0 \|\| delay > 15) {
	195	dev_dbg(wm->dev, "supplied delay out of range.");
	196	delay = 4;
	197	}
	198	dig1 &= 0xff0f;
	199	dig1 \|= WM97XX_DELAY(delay);
	200	dev_dbg(wm->dev, "setting adc sample delay to %d u Secs.",
	201	delay_table[delay]);
	202
	203	/* mask */
	204	dig2 \|= ((mask & 0x3) << 6);
	205	if (mask) {
	206	u16 reg;
	207	/* Set GPIO4 as Mask Pin*/
	208	reg = wm97xx_reg_read(wm, AC97_MISC_AFE);
	209	wm97xx_reg_write(wm, AC97_MISC_AFE, reg \| WM97XX_GPIO_4);
	210	reg = wm97xx_reg_read(wm, AC97_GPIO_CFG);
	211	wm97xx_reg_write(wm, AC97_GPIO_CFG, reg \| WM97XX_GPIO_4);
	212	}
	213
	214	/* wait - coord mode */
	215	if (coord)
	216	dig2 \|= WM9712_WAIT;
	217
	218	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, dig1);
	219	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, dig2);
	220	}
	221
	222	static void wm9712_dig_enable(struct wm97xx *wm, int enable)
	223	{
	224	u16 dig2 = wm->dig[2];
	225
	226	if (enable) {
	227	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2,
	228	dig2 \| WM97XX_PRP_DET_DIG);
	229	wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); /* dummy read */
	230	} else
	231	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2,
	232	dig2 & ~WM97XX_PRP_DET_DIG);
	233	}
	234
	235	static void wm9712_aux_prepare(struct wm97xx *wm)
	236	{
	237	memcpy(wm->dig_save, wm->dig, sizeof(wm->dig));
	238	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, 0);
	239	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, WM97XX_PRP_DET_DIG);
	240	}
	241
	242	static void wm9712_dig_restore(struct wm97xx *wm)
	243	{
	244	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, wm->dig_save[1]);
	245	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, wm->dig_save[2]);
	246	}
	247
	248	static inline int is_pden(struct wm97xx *wm)
	249	{
	250	return wm->dig[2] & WM9712_PDEN;
	251	}
	252
	253	/*
	254	* Read a sample from the WM9712 adc in polling mode.
	255	*/
	256	static int wm9712_poll_sample(struct wm97xx wm, int adcsel, int sample)
257	{
258	int timeout = 5 * delay;
259
260	if (!wm->pen_probably_down) {
261	u16 data = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
262	if (!(data & WM97XX_PEN_DOWN))
263	return RC_PENUP;
264	wm->pen_probably_down = 1;
265	}
266
267	/* set up digitiser */
268	if (adcsel & 0x8000)
269	adcsel = ((adcsel & 0x7fff) + 3) << 12;
270
271	if (wm->mach_ops && wm->mach_ops->pre_sample)
272	wm->mach_ops->pre_sample(adcsel);
273	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1,
274	adcsel \| WM97XX_POLL \| WM97XX_DELAY(delay));
275
276	/* wait 3 AC97 time slots + delay for conversion */
277	poll_delay(delay);
278
279	/* wait for POLL to go low */
280	while ((wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER1) & WM97XX_POLL)
281	&& timeout) {
282	udelay(AC97_LINK_FRAME);
283	timeout--;
284	}
285
286	if (timeout <= 0) {
287	/* If PDEN is set, we can get a timeout when pen goes up */
288	if (is_pden(wm))
289	wm->pen_probably_down = 0;
290	else
291	dev_dbg(wm->dev, "adc sample timeout");
292	return RC_PENUP;
293	}
294
295	*sample = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
296	if (wm->mach_ops && wm->mach_ops->post_sample)
297	wm->mach_ops->post_sample(adcsel);
298
299	/* check we have correct sample */
300	if ((*sample & WM97XX_ADCSEL_MASK) != adcsel) {
301	dev_dbg(wm->dev, "adc wrong sample, read %x got %x", adcsel,
302	*sample & WM97XX_ADCSEL_MASK);
303	return RC_PENUP;
304	}
305
306	if (!(*sample & WM97XX_PEN_DOWN)) {
307	wm->pen_probably_down = 0;
308	return RC_PENUP;
309	}
310
311	return RC_VALID;
312	}
313
314	/*
315	* Read a coord from the WM9712 adc in polling mode.
316	*/
317	static int wm9712_poll_coord(struct wm97xx wm, struct wm97xx_data data)
318	{
319	int timeout = 5 * delay;
320
321	if (!wm->pen_probably_down) {
322	u16 data_rd = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
323	if (!(data_rd & WM97XX_PEN_DOWN))
324	return RC_PENUP;
325	wm->pen_probably_down = 1;
326	}
327
328	/* set up digitiser */
329	if (wm->mach_ops && wm->mach_ops->pre_sample)
330	wm->mach_ops->pre_sample(WM97XX_ADCSEL_X \| WM97XX_ADCSEL_Y);
331
332	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1,
333	WM97XX_COO \| WM97XX_POLL \| WM97XX_DELAY(delay));
334
335	/* wait 3 AC97 time slots + delay for conversion and read x */
336	poll_delay(delay);
337	data->x = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
338	/* wait for POLL to go low */
339	while ((wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER1) & WM97XX_POLL)
340	&& timeout) {
341	udelay(AC97_LINK_FRAME);
342	timeout--;
343	}
344
345	if (timeout <= 0) {
346	/* If PDEN is set, we can get a timeout when pen goes up */
347	if (is_pden(wm))
348	wm->pen_probably_down = 0;
349	else
350	dev_dbg(wm->dev, "adc sample timeout");
351	return RC_PENUP;
352	}
353
354	/* read back y data */
355	data->y = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
356	if (pil)
357	data->p = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
358	else
359	data->p = DEFAULT_PRESSURE;
360
361	if (wm->mach_ops && wm->mach_ops->post_sample)
362	wm->mach_ops->post_sample(WM97XX_ADCSEL_X \| WM97XX_ADCSEL_Y);
363
364	/* check we have correct sample */
365	if (!(data->x & WM97XX_ADCSEL_X) \|\| !(data->y & WM97XX_ADCSEL_Y))
366	goto err;
367	if (pil && !(data->p & WM97XX_ADCSEL_PRES))
368	goto err;
369
370	if (!(data->x & WM97XX_PEN_DOWN) \|\| !(data->y & WM97XX_PEN_DOWN)) {
371	wm->pen_probably_down = 0;
372	return RC_PENUP;
373	}
374	return RC_VALID;
375	err:
376	return 0;
377	}
378
379	/*
380	* Sample the WM9712 touchscreen in polling mode
381	*/
382	static int wm9712_poll_touch(struct wm97xx wm, struct wm97xx_data data)
383	{
384	int rc;
385
386	if (coord) {
387	rc = wm9712_poll_coord(wm, data);
388	if (rc != RC_VALID)
389	return rc;
390	} else {
391	rc = wm9712_poll_sample(wm, WM97XX_ADCSEL_X, &data->x);
392	if (rc != RC_VALID)
393	return rc;
394
395	rc = wm9712_poll_sample(wm, WM97XX_ADCSEL_Y, &data->y);
396	if (rc != RC_VALID)
397	return rc;
398
399	if (pil && !five_wire) {
400	rc = wm9712_poll_sample(wm, WM97XX_ADCSEL_PRES,
401	&data->p);
402	if (rc != RC_VALID)
403	return rc;
404	} else
405	data->p = DEFAULT_PRESSURE;
406	}
407	return RC_VALID;
408	}
409
410	/*
411	* Enable WM9712 continuous mode, i.e. touch data is streamed across
412	* an AC97 slot
413	*/
414	static int wm9712_acc_enable(struct wm97xx *wm, int enable)
415	{
416	u16 dig1, dig2;
417	int ret = 0;
418
419	dig1 = wm->dig[1];
420	dig2 = wm->dig[2];
421
422	if (enable) {
423	/* continous mode */
424	if (wm->mach_ops->acc_startup) {
425	ret = wm->mach_ops->acc_startup(wm);
426	if (ret < 0)
427	return ret;
428	}
429	dig1 &= ~(WM97XX_CM_RATE_MASK \| WM97XX_ADCSEL_MASK \|
430	WM97XX_DELAY_MASK \| WM97XX_SLT_MASK);
431	dig1 \|= WM97XX_CTC \| WM97XX_COO \| WM97XX_SLEN \|
432	WM97XX_DELAY(delay) \|
433	WM97XX_SLT(wm->acc_slot) \|
434	WM97XX_RATE(wm->acc_rate);
435	if (pil)
436	dig1 \|= WM97XX_ADCSEL_PRES;
437	dig2 \|= WM9712_PDEN;
438	} else {
439	dig1 &= ~(WM97XX_CTC \| WM97XX_COO \| WM97XX_SLEN);
440	dig2 &= ~WM9712_PDEN;
441	if (wm->mach_ops->acc_shutdown)
442	wm->mach_ops->acc_shutdown(wm);
443	}
444
445	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, dig1);
446	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, dig2);
447
448	return 0;
449	}
450
451	struct wm97xx_codec_drv wm9712_codec = {
452	.id = WM9712_ID2,
453	.name = "wm9712",
454	.poll_sample = wm9712_poll_sample,
455	.poll_touch = wm9712_poll_touch,
456	.acc_enable = wm9712_acc_enable,
457	.phy_init = wm9712_phy_init,
458	.dig_enable = wm9712_dig_enable,
459	.dig_restore = wm9712_dig_restore,
460	.aux_prepare = wm9712_aux_prepare,
461	};
462	EXPORT_SYMBOL_GPL(wm9712_codec);
463
464	/* Module information */
465	MODULE_AUTHOR("Liam Girdwood <liam.girdwood@wolfsonmicro.com>");
466	MODULE_DESCRIPTION("WM9712 Touch Screen Driver");
467	MODULE_LICENSE("GPL");