[linux-2.6-block.git] / drivers / mfd / ucb1x00-ts.c

/*
 *  Touchscreen driver for UCB1x00-based touchscreens
 *
 *  Copyright (C) 2001 Russell King, All Rights Reserved.
 *  Copyright (C) 2005 Pavel Machek
 *
 * 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.
 *
 * 21-Jan-2002 <jco@ict.es> :
 *
 * Added support for synchronous A/D mode. This mode is useful to
 * avoid noise induced in the touchpanel by the LCD, provided that
 * the UCB1x00 has a valid LCD sync signal routed to its ADCSYNC pin.
 * It is important to note that the signal connected to the ADCSYNC
 * pin should provide pulses even when the LCD is blanked, otherwise
 * a pen touch needed to unblank the LCD will never be read.
 */
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/sched.h>
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/input.h>
#include <linux/device.h>
#include <linux/freezer.h>
#include <linux/slab.h>
#include <linux/kthread.h>
#include <linux/mfd/ucb1x00.h>

#include <mach/dma.h>
#include <mach/collie.h>
#include <asm/mach-types.h>


struct ucb1x00_ts {
	struct input_dev	*idev;
	struct ucb1x00		*ucb;

	wait_queue_head_t	irq_wait;
	struct task_struct	*rtask;
	u16			x_res;
	u16			y_res;

	unsigned int		restart:1;
	unsigned int		adcsync:1;
};

static int adcsync;

static inline void ucb1x00_ts_evt_add(struct ucb1x00_ts *ts, u16 pressure, u16 x, u16 y)
{
	struct input_dev *idev = ts->idev;

	input_report_abs(idev, ABS_X, x);
	input_report_abs(idev, ABS_Y, y);
	input_report_abs(idev, ABS_PRESSURE, pressure);
	input_report_key(idev, BTN_TOUCH, 1);
	input_sync(idev);
}

static inline void ucb1x00_ts_event_release(struct ucb1x00_ts *ts)
{
	struct input_dev *idev = ts->idev;

	input_report_abs(idev, ABS_PRESSURE, 0);
	input_report_key(idev, BTN_TOUCH, 0);
	input_sync(idev);
}

/*
 * Switch to interrupt mode.
 */
static inline void ucb1x00_ts_mode_int(struct ucb1x00_ts *ts)
{
	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
			UCB_TS_CR_TSMX_POW | UCB_TS_CR_TSPX_POW |
			UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_GND |
			UCB_TS_CR_MODE_INT);
}

/*
 * Switch to pressure mode, and read pressure.  We don't need to wait
 * here, since both plates are being driven.
 */
static inline unsigned int ucb1x00_ts_read_pressure(struct ucb1x00_ts *ts)
{
	if (machine_is_collie()) {
		ucb1x00_io_write(ts->ucb, COLLIE_TC35143_GPIO_TBL_CHK, 0);
		ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
				  UCB_TS_CR_TSPX_POW | UCB_TS_CR_TSMX_POW |
				  UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);

		udelay(55);

		return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_AD2, ts->adcsync);
	} else {
		ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
				  UCB_TS_CR_TSMX_POW | UCB_TS_CR_TSPX_POW |
				  UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_GND |
				  UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);

		return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPY, ts->adcsync);
	}
}

/*
 * Switch to X position mode and measure Y plate.  We switch the plate
 * configuration in pressure mode, then switch to position mode.  This
 * gives a faster response time.  Even so, we need to wait about 55us
 * for things to stabilise.
 */
static inline unsigned int ucb1x00_ts_read_xpos(struct ucb1x00_ts *ts)
{
	if (machine_is_collie())
		ucb1x00_io_write(ts->ucb, 0, COLLIE_TC35143_GPIO_TBL_CHK);
	else {
		ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
				  UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
				  UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
		ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
				  UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
				  UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
	}
	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
			UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
			UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);

	udelay(55);

	return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPY, ts->adcsync);
}

/*
 * Switch to Y position mode and measure X plate.  We switch the plate
 * configuration in pressure mode, then switch to position mode.  This
 * gives a faster response time.  Even so, we need to wait about 55us
 * for things to stabilise.
 */
static inline unsigned int ucb1x00_ts_read_ypos(struct ucb1x00_ts *ts)
{
	if (machine_is_collie())
		ucb1x00_io_write(ts->ucb, 0, COLLIE_TC35143_GPIO_TBL_CHK);
	else {
		ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
				  UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
				  UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
		ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
				  UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
				  UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
	}

	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
			UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
			UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);

	udelay(55);

	return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPX, ts->adcsync);
}

/*
 * Switch to X plate resistance mode.  Set MX to ground, PX to
 * supply.  Measure current.
 */
static inline unsigned int ucb1x00_ts_read_xres(struct ucb1x00_ts *ts)
{
	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
			UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
			UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
	return ucb1x00_adc_read(ts->ucb, 0, ts->adcsync);
}

/*
 * Switch to Y plate resistance mode.  Set MY to ground, PY to
 * supply.  Measure current.
 */
static inline unsigned int ucb1x00_ts_read_yres(struct ucb1x00_ts *ts)
{
	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
			UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
			UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
	return ucb1x00_adc_read(ts->ucb, 0, ts->adcsync);
}

static inline int ucb1x00_ts_pen_down(struct ucb1x00_ts *ts)
{
	unsigned int val = ucb1x00_reg_read(ts->ucb, UCB_TS_CR);

	if (machine_is_collie())
		return (!(val & (UCB_TS_CR_TSPX_LOW)));
	else
		return (val & (UCB_TS_CR_TSPX_LOW | UCB_TS_CR_TSMX_LOW));
}

/*
 * This is a RT kernel thread that handles the ADC accesses
 * (mainly so we can use semaphores in the UCB1200 core code
 * to serialise accesses to the ADC).
 */
static int ucb1x00_thread(void *_ts)
{
	struct ucb1x00_ts *ts = _ts;
	DECLARE_WAITQUEUE(wait, current);
	int valid = 0;

	set_freezable();
	add_wait_queue(&ts->irq_wait, &wait);
	while (!kthread_should_stop()) {
		unsigned int x, y, p;
		signed long timeout;

		ts->restart = 0;

		ucb1x00_adc_enable(ts->ucb);

		x = ucb1x00_ts_read_xpos(ts);
		y = ucb1x00_ts_read_ypos(ts);
		p = ucb1x00_ts_read_pressure(ts);

		/*
		 * Switch back to interrupt mode.
		 */
		ucb1x00_ts_mode_int(ts);
		ucb1x00_adc_disable(ts->ucb);

		msleep(10);

		ucb1x00_enable(ts->ucb);


		if (ucb1x00_ts_pen_down(ts)) {
			set_current_state(TASK_INTERRUPTIBLE);

			ucb1x00_enable_irq(ts->ucb, UCB_IRQ_TSPX, machine_is_collie() ? UCB_RISING : UCB_FALLING);
			ucb1x00_disable(ts->ucb);

			/*
			 * If we spat out a valid sample set last time,
			 * spit out a "pen off" sample here.
			 */
			if (valid) {
				ucb1x00_ts_event_release(ts);
				valid = 0;
			}

			timeout = MAX_SCHEDULE_TIMEOUT;
		} else {
			ucb1x00_disable(ts->ucb);

			/*
			 * Filtering is policy.  Policy belongs in user
			 * space.  We therefore leave it to user space
			 * to do any filtering they please.
			 */
			if (!ts->restart) {
				ucb1x00_ts_evt_add(ts, p, x, y);
				valid = 1;
			}

			set_current_state(TASK_INTERRUPTIBLE);
			timeout = HZ / 100;
		}

		try_to_freeze();

		schedule_timeout(timeout);
	}

	remove_wait_queue(&ts->irq_wait, &wait);

	ts->rtask = NULL;
	return 0;
}

/*
 * We only detect touch screen _touches_ with this interrupt
 * handler, and even then we just schedule our task.
 */
static void ucb1x00_ts_irq(int idx, void *id)
{
	struct ucb1x00_ts *ts = id;

	ucb1x00_disable_irq(ts->ucb, UCB_IRQ_TSPX, UCB_FALLING);
	wake_up(&ts->irq_wait);
}

static int ucb1x00_ts_open(struct input_dev *idev)
{
	struct ucb1x00_ts *ts = input_get_drvdata(idev);
	int ret = 0;

	BUG_ON(ts->rtask);

	init_waitqueue_head(&ts->irq_wait);
	ret = ucb1x00_hook_irq(ts->ucb, UCB_IRQ_TSPX, ucb1x00_ts_irq, ts);
	if (ret < 0)
		goto out;

	/*
	 * If we do this at all, we should allow the user to
	 * measure and read the X and Y resistance at any time.
	 */
	ucb1x00_adc_enable(ts->ucb);
	ts->x_res = ucb1x00_ts_read_xres(ts);
	ts->y_res = ucb1x00_ts_read_yres(ts);
	ucb1x00_adc_disable(ts->ucb);

	ts->rtask = kthread_run(ucb1x00_thread, ts, "ktsd");
	if (!IS_ERR(ts->rtask)) {
		ret = 0;
	} else {
		ucb1x00_free_irq(ts->ucb, UCB_IRQ_TSPX, ts);
		ts->rtask = NULL;
		ret = -EFAULT;
	}

 out:
	return ret;
}

/*
 * Release touchscreen resources.  Disable IRQs.
 */
static void ucb1x00_ts_close(struct input_dev *idev)
{
	struct ucb1x00_ts *ts = input_get_drvdata(idev);

	if (ts->rtask)
		kthread_stop(ts->rtask);

	ucb1x00_enable(ts->ucb);
	ucb1x00_free_irq(ts->ucb, UCB_IRQ_TSPX, ts);
	ucb1x00_reg_write(ts->ucb, UCB_TS_CR, 0);
	ucb1x00_disable(ts->ucb);
}

#ifdef CONFIG_PM
static int ucb1x00_ts_resume(struct ucb1x00_dev *dev)
{
	struct ucb1x00_ts *ts = dev->priv;

	if (ts->rtask != NULL) {
		/*
		 * Restart the TS thread to ensure the
		 * TS interrupt mode is set up again
		 * after sleep.
		 */
		ts->restart = 1;
		wake_up(&ts->irq_wait);
	}
	return 0;
}
#else
#define ucb1x00_ts_resume NULL
#endif


/*
 * Initialisation.
 */
static int ucb1x00_ts_add(struct ucb1x00_dev *dev)
{
	struct ucb1x00_ts *ts;
	struct input_dev *idev;
	int err;

	ts = kzalloc(sizeof(struct ucb1x00_ts), GFP_KERNEL);
	idev = input_allocate_device();
	if (!ts || !idev) {
		err = -ENOMEM;
		goto fail;
	}

	ts->ucb = dev->ucb;
	ts->idev = idev;
	ts->adcsync = adcsync ? UCB_SYNC : UCB_NOSYNC;

	idev->name       = "Touchscreen panel";
	idev->id.product = ts->ucb->id;
	idev->open       = ucb1x00_ts_open;
	idev->close      = ucb1x00_ts_close;

	idev->evbit[0]   = BIT_MASK(EV_ABS) | BIT_MASK(EV_KEY);
	idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);

	input_set_drvdata(idev, ts);

	ucb1x00_adc_enable(ts->ucb);
	ts->x_res = ucb1x00_ts_read_xres(ts);
	ts->y_res = ucb1x00_ts_read_yres(ts);
	ucb1x00_adc_disable(ts->ucb);

	input_set_abs_params(idev, ABS_X, 0, ts->x_res, 0, 0);
	input_set_abs_params(idev, ABS_Y, 0, ts->y_res, 0, 0);
	input_set_abs_params(idev, ABS_PRESSURE, 0, 0, 0, 0);

	err = input_register_device(idev);
	if (err)
		goto fail;

	dev->priv = ts;

	return 0;

 fail:
	input_free_device(idev);
	kfree(ts);
	return err;
}

static void ucb1x00_ts_remove(struct ucb1x00_dev *dev)
{
	struct ucb1x00_ts *ts = dev->priv;

	input_unregister_device(ts->idev);
	kfree(ts);
}

static struct ucb1x00_driver ucb1x00_ts_driver = {
	.add		= ucb1x00_ts_add,
	.remove		= ucb1x00_ts_remove,
	.resume		= ucb1x00_ts_resume,
};

static int __init ucb1x00_ts_init(void)
{
	return ucb1x00_register_driver(&ucb1x00_ts_driver);
}

static void __exit ucb1x00_ts_exit(void)
{
	ucb1x00_unregister_driver(&ucb1x00_ts_driver);
}

module_param(adcsync, int, 0444);
module_init(ucb1x00_ts_init);
module_exit(ucb1x00_ts_exit);

MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
MODULE_DESCRIPTION("UCB1x00 touchscreen driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
acb45439	1	/*
5437775e	2	* Touchscreen driver for UCB1x00-based touchscreens
acb45439 RK	3	*
acb45439 RK	4	* Copyright (C) 2001 Russell King, All Rights Reserved.
5437775e	5	* Copyright (C) 2005 Pavel Machek
acb45439 RK	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*
	11	* 21-Jan-2002 <jco@ict.es> :
	12	*
	13	* Added support for synchronous A/D mode. This mode is useful to
	14	* avoid noise induced in the touchpanel by the LCD, provided that
	15	* the UCB1x00 has a valid LCD sync signal routed to its ADCSYNC pin.
	16	* It is important to note that the signal connected to the ADCSYNC
	17	* pin should provide pulses even when the LCD is blanked, otherwise
	18	* a pen touch needed to unblank the LCD will never be read.
	19	*/
acb45439 RK	20	#include <linux/module.h>
	21	#include <linux/moduleparam.h>
	22	#include <linux/init.h>
	23	#include <linux/smp.h>
acb45439 RK	24	#include <linux/sched.h>
	25	#include <linux/completion.h>
	26	#include <linux/delay.h>
	27	#include <linux/string.h>
	28	#include <linux/input.h>
	29	#include <linux/device.h>
7dfb7103	30	#include <linux/freezer.h>
acb45439	31	#include <linux/slab.h>
5437775e	32	#include <linux/kthread.h>
c8602edf	33	#include <linux/mfd/ucb1x00.h>
acb45439	34
dcea83ad	35	#include <mach/dma.h>
a09e64fb	36	#include <mach/collie.h>
17532989	37	#include <asm/mach-types.h>
acb45439	38
acb45439 RK	39
	40
	41	struct ucb1x00_ts {
bd622663	42	struct input_dev *idev;
acb45439 RK	43	struct ucb1x00 *ucb;
	44
	45	wait_queue_head_t irq_wait;
acb45439	46	struct task_struct *rtask;
acb45439 RK	47	u16 x_res;
	48	u16 y_res;
	49
6b9ea421 RK	50	unsigned int restart:1;
6b9ea421 RK	51	unsigned int adcsync:1;
acb45439 RK	52	};
	53
	54	static int adcsync;
	55
	56	static inline void ucb1x00_ts_evt_add(struct ucb1x00_ts *ts, u16 pressure, u16 x, u16 y)
	57	{
1393c3ed	58	struct input_dev *idev = ts->idev;
08c67d2a	59
1393c3ed NP	60	input_report_abs(idev, ABS_X, x);
	61	input_report_abs(idev, ABS_Y, y);
	62	input_report_abs(idev, ABS_PRESSURE, pressure);
de8c8b06	63	input_report_key(idev, BTN_TOUCH, 1);
1393c3ed	64	input_sync(idev);
acb45439 RK	65	}
	66
	67	static inline void ucb1x00_ts_event_release(struct ucb1x00_ts *ts)
	68	{
1393c3ed	69	struct input_dev *idev = ts->idev;
08c67d2a	70
1393c3ed	71	input_report_abs(idev, ABS_PRESSURE, 0);
de8c8b06	72	input_report_key(idev, BTN_TOUCH, 0);
1393c3ed	73	input_sync(idev);
acb45439 RK	74	}
	75
	76	/*
	77	* Switch to interrupt mode.
	78	*/
	79	static inline void ucb1x00_ts_mode_int(struct ucb1x00_ts *ts)
	80	{
	81	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
	82	UCB_TS_CR_TSMX_POW \| UCB_TS_CR_TSPX_POW \|
	83	UCB_TS_CR_TSMY_GND \| UCB_TS_CR_TSPY_GND \|
	84	UCB_TS_CR_MODE_INT);
	85	}
	86
	87	/*
	88	* Switch to pressure mode, and read pressure. We don't need to wait
	89	* here, since both plates are being driven.
	90	*/
	91	static inline unsigned int ucb1x00_ts_read_pressure(struct ucb1x00_ts *ts)
	92	{
17532989 PM	93	if (machine_is_collie()) {
	94	ucb1x00_io_write(ts->ucb, COLLIE_TC35143_GPIO_TBL_CHK, 0);
	95	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
	96	UCB_TS_CR_TSPX_POW \| UCB_TS_CR_TSMX_POW \|
	97	UCB_TS_CR_MODE_POS \| UCB_TS_CR_BIAS_ENA);
	98
	99	udelay(55);
	100
	101	return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_AD2, ts->adcsync);
	102	} else {
	103	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
	104	UCB_TS_CR_TSMX_POW \| UCB_TS_CR_TSPX_POW \|
	105	UCB_TS_CR_TSMY_GND \| UCB_TS_CR_TSPY_GND \|
	106	UCB_TS_CR_MODE_PRES \| UCB_TS_CR_BIAS_ENA);
	107
	108	return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPY, ts->adcsync);
	109	}
acb45439 RK	110	}
	111
	112	/*
	113	* Switch to X position mode and measure Y plate. We switch the plate
	114	* configuration in pressure mode, then switch to position mode. This
	115	* gives a faster response time. Even so, we need to wait about 55us
	116	* for things to stabilise.
	117	*/
	118	static inline unsigned int ucb1x00_ts_read_xpos(struct ucb1x00_ts *ts)
	119	{
17532989 PM	120	if (machine_is_collie())
	121	ucb1x00_io_write(ts->ucb, 0, COLLIE_TC35143_GPIO_TBL_CHK);
	122	else {
	123	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
	124	UCB_TS_CR_TSMX_GND \| UCB_TS_CR_TSPX_POW \|
	125	UCB_TS_CR_MODE_PRES \| UCB_TS_CR_BIAS_ENA);
	126	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
	127	UCB_TS_CR_TSMX_GND \| UCB_TS_CR_TSPX_POW \|
	128	UCB_TS_CR_MODE_PRES \| UCB_TS_CR_BIAS_ENA);
	129	}
acb45439 RK	130	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
	131	UCB_TS_CR_TSMX_GND \| UCB_TS_CR_TSPX_POW \|
	132	UCB_TS_CR_MODE_POS \| UCB_TS_CR_BIAS_ENA);
	133
	134	udelay(55);
	135
	136	return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPY, ts->adcsync);
	137	}
	138
	139	/*
	140	* Switch to Y position mode and measure X plate. We switch the plate
	141	* configuration in pressure mode, then switch to position mode. This
	142	* gives a faster response time. Even so, we need to wait about 55us
	143	* for things to stabilise.
	144	*/
	145	static inline unsigned int ucb1x00_ts_read_ypos(struct ucb1x00_ts *ts)
	146	{
17532989 PM	147	if (machine_is_collie())
	148	ucb1x00_io_write(ts->ucb, 0, COLLIE_TC35143_GPIO_TBL_CHK);
	149	else {
	150	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
	151	UCB_TS_CR_TSMY_GND \| UCB_TS_CR_TSPY_POW \|
	152	UCB_TS_CR_MODE_PRES \| UCB_TS_CR_BIAS_ENA);
	153	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
	154	UCB_TS_CR_TSMY_GND \| UCB_TS_CR_TSPY_POW \|
	155	UCB_TS_CR_MODE_PRES \| UCB_TS_CR_BIAS_ENA);
	156	}
	157
acb45439 RK	158	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
	159	UCB_TS_CR_TSMY_GND \| UCB_TS_CR_TSPY_POW \|
	160	UCB_TS_CR_MODE_POS \| UCB_TS_CR_BIAS_ENA);
	161
	162	udelay(55);
	163
	164	return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPX, ts->adcsync);
	165	}
	166
	167	/*
	168	* Switch to X plate resistance mode. Set MX to ground, PX to
	169	* supply. Measure current.
	170	*/
	171	static inline unsigned int ucb1x00_ts_read_xres(struct ucb1x00_ts *ts)
	172	{
	173	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
	174	UCB_TS_CR_TSMX_GND \| UCB_TS_CR_TSPX_POW \|
	175	UCB_TS_CR_MODE_PRES \| UCB_TS_CR_BIAS_ENA);
	176	return ucb1x00_adc_read(ts->ucb, 0, ts->adcsync);
	177	}
	178
	179	/*
	180	* Switch to Y plate resistance mode. Set MY to ground, PY to
	181	* supply. Measure current.
	182	*/
	183	static inline unsigned int ucb1x00_ts_read_yres(struct ucb1x00_ts *ts)
	184	{
	185	ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
	186	UCB_TS_CR_TSMY_GND \| UCB_TS_CR_TSPY_POW \|
	187	UCB_TS_CR_MODE_PRES \| UCB_TS_CR_BIAS_ENA);
	188	return ucb1x00_adc_read(ts->ucb, 0, ts->adcsync);
	189	}
	190
17532989 PM	191	static inline int ucb1x00_ts_pen_down(struct ucb1x00_ts *ts)
	192	{
	193	unsigned int val = ucb1x00_reg_read(ts->ucb, UCB_TS_CR);
08c67d2a	194
17532989 PM	195	if (machine_is_collie())
	196	return (!(val & (UCB_TS_CR_TSPX_LOW)));
	197	else
	198	return (val & (UCB_TS_CR_TSPX_LOW \| UCB_TS_CR_TSMX_LOW));
	199	}
	200
acb45439 RK	201	/*
	202	* This is a RT kernel thread that handles the ADC accesses
	203	* (mainly so we can use semaphores in the UCB1200 core code
	204	* to serialise accesses to the ADC).
	205	*/
	206	static int ucb1x00_thread(void *_ts)
	207	{
	208	struct ucb1x00_ts *ts = _ts;
f7440b0e	209	DECLARE_WAITQUEUE(wait, current);
1124d5ca	210	int valid = 0;
acb45439	211
83144186	212	set_freezable();
acb45439	213	add_wait_queue(&ts->irq_wait, &wait);
5437775e	214	while (!kthread_should_stop()) {
17532989	215	unsigned int x, y, p;
acb45439 RK	216	signed long timeout;
	217
	218	ts->restart = 0;
	219
	220	ucb1x00_adc_enable(ts->ucb);
	221
	222	x = ucb1x00_ts_read_xpos(ts);
	223	y = ucb1x00_ts_read_ypos(ts);
	224	p = ucb1x00_ts_read_pressure(ts);
	225
	226	/*
	227	* Switch back to interrupt mode.
	228	*/
	229	ucb1x00_ts_mode_int(ts);
	230	ucb1x00_adc_disable(ts->ucb);
	231
5437775e	232	msleep(10);
acb45439 RK	233
acb45439 RK	234	ucb1x00_enable(ts->ucb);
acb45439	235
17532989 PM	236
17532989 PM	237	if (ucb1x00_ts_pen_down(ts)) {
f7440b0e	238	set_current_state(TASK_INTERRUPTIBLE);
acb45439	239
17532989	240	ucb1x00_enable_irq(ts->ucb, UCB_IRQ_TSPX, machine_is_collie() ? UCB_RISING : UCB_FALLING);
acb45439 RK	241	ucb1x00_disable(ts->ucb);
	242
	243	/*
	244	* If we spat out a valid sample set last time,
	245	* spit out a "pen off" sample here.
	246	*/
	247	if (valid) {
	248	ucb1x00_ts_event_release(ts);
	249	valid = 0;
	250	}
	251
	252	timeout = MAX_SCHEDULE_TIMEOUT;
	253	} else {
	254	ucb1x00_disable(ts->ucb);
	255
	256	/*
	257	* Filtering is policy. Policy belongs in user
	258	* space. We therefore leave it to user space
	259	* to do any filtering they please.
	260	*/
	261	if (!ts->restart) {
	262	ucb1x00_ts_evt_add(ts, p, x, y);
	263	valid = 1;
	264	}
	265
f7440b0e	266	set_current_state(TASK_INTERRUPTIBLE);
acb45439 RK	267	timeout = HZ / 100;
	268	}
	269
	270	try_to_freeze();
	271
	272	schedule_timeout(timeout);
acb45439 RK	273	}
	274
	275	remove_wait_queue(&ts->irq_wait, &wait);
	276
	277	ts->rtask = NULL;
5437775e	278	return 0;
acb45439 RK	279	}
	280
	281	/*
	282	* We only detect touch screen _touches_ with this interrupt
	283	* handler, and even then we just schedule our task.
	284	*/
	285	static void ucb1x00_ts_irq(int idx, void *id)
	286	{
	287	struct ucb1x00_ts *ts = id;
08c67d2a	288
acb45439 RK	289	ucb1x00_disable_irq(ts->ucb, UCB_IRQ_TSPX, UCB_FALLING);
	290	wake_up(&ts->irq_wait);
	291	}
	292
	293	static int ucb1x00_ts_open(struct input_dev *idev)
	294	{
26be5a50	295	struct ucb1x00_ts *ts = input_get_drvdata(idev);
acb45439 RK	296	int ret = 0;
acb45439 RK	297
5437775e	298	BUG_ON(ts->rtask);
acb45439 RK	299
	300	init_waitqueue_head(&ts->irq_wait);
	301	ret = ucb1x00_hook_irq(ts->ucb, UCB_IRQ_TSPX, ucb1x00_ts_irq, ts);
	302	if (ret < 0)
	303	goto out;
	304
	305	/*
	306	* If we do this at all, we should allow the user to
	307	* measure and read the X and Y resistance at any time.
	308	*/
	309	ucb1x00_adc_enable(ts->ucb);
	310	ts->x_res = ucb1x00_ts_read_xres(ts);
	311	ts->y_res = ucb1x00_ts_read_yres(ts);
	312	ucb1x00_adc_disable(ts->ucb);
	313
5437775e PM	314	ts->rtask = kthread_run(ucb1x00_thread, ts, "ktsd");
5437775e PM	315	if (!IS_ERR(ts->rtask)) {
acb45439 RK	316	ret = 0;
	317	} else {
	318	ucb1x00_free_irq(ts->ucb, UCB_IRQ_TSPX, ts);
5437775e PM	319	ts->rtask = NULL;
5437775e PM	320	ret = -EFAULT;
acb45439 RK	321	}
	322
	323	out:
acb45439 RK	324	return ret;
	325	}
	326
	327	/*
	328	* Release touchscreen resources. Disable IRQs.
	329	*/
	330	static void ucb1x00_ts_close(struct input_dev *idev)
	331	{
26be5a50	332	struct ucb1x00_ts *ts = input_get_drvdata(idev);
acb45439	333
5437775e PM	334	if (ts->rtask)
5437775e PM	335	kthread_stop(ts->rtask);
acb45439	336
5437775e PM	337	ucb1x00_enable(ts->ucb);
	338	ucb1x00_free_irq(ts->ucb, UCB_IRQ_TSPX, ts);
	339	ucb1x00_reg_write(ts->ucb, UCB_TS_CR, 0);
	340	ucb1x00_disable(ts->ucb);
acb45439 RK	341	}
	342
	343	#ifdef CONFIG_PM
	344	static int ucb1x00_ts_resume(struct ucb1x00_dev *dev)
	345	{
	346	struct ucb1x00_ts *ts = dev->priv;
	347
	348	if (ts->rtask != NULL) {
	349	/*
	350	* Restart the TS thread to ensure the
	351	* TS interrupt mode is set up again
	352	* after sleep.
	353	*/
	354	ts->restart = 1;
	355	wake_up(&ts->irq_wait);
	356	}
	357	return 0;
	358	}
	359	#else
	360	#define ucb1x00_ts_resume NULL
	361	#endif
	362
	363
	364	/*
	365	* Initialisation.
	366	*/
	367	static int ucb1x00_ts_add(struct ucb1x00_dev *dev)
	368	{
	369	struct ucb1x00_ts *ts;
08c67d2a DT	370	struct input_dev *idev;
08c67d2a DT	371	int err;
acb45439	372
bd622663	373	ts = kzalloc(sizeof(struct ucb1x00_ts), GFP_KERNEL);
08c67d2a DT	374	idev = input_allocate_device();
	375	if (!ts \|\| !idev) {
	376	err = -ENOMEM;
	377	goto fail;
bd622663	378	}
acb45439 RK	379
acb45439 RK	380	ts->ucb = dev->ucb;
08c67d2a	381	ts->idev = idev;
acb45439	382	ts->adcsync = adcsync ? UCB_SYNC : UCB_NOSYNC;
acb45439	383
08c67d2a DT	384	idev->name = "Touchscreen panel";
	385	idev->id.product = ts->ucb->id;
	386	idev->open = ucb1x00_ts_open;
	387	idev->close = ucb1x00_ts_close;
acb45439	388
de8c8b06 JF	389	idev->evbit[0] = BIT_MASK(EV_ABS) \| BIT_MASK(EV_KEY);
de8c8b06 JF	390	idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
acb45439	391
26be5a50 DT	392	input_set_drvdata(idev, ts);
26be5a50 DT	393
9063f1f1 JF	394	ucb1x00_adc_enable(ts->ucb);
	395	ts->x_res = ucb1x00_ts_read_xres(ts);
	396	ts->y_res = ucb1x00_ts_read_yres(ts);
	397	ucb1x00_adc_disable(ts->ucb);
	398
	399	input_set_abs_params(idev, ABS_X, 0, ts->x_res, 0, 0);
	400	input_set_abs_params(idev, ABS_Y, 0, ts->y_res, 0, 0);
	401	input_set_abs_params(idev, ABS_PRESSURE, 0, 0, 0, 0);
	402
08c67d2a DT	403	err = input_register_device(idev);
	404	if (err)
	405	goto fail;
acb45439 RK	406
	407	dev->priv = ts;
	408
	409	return 0;
08c67d2a DT	410
	411	fail:
	412	input_free_device(idev);
	413	kfree(ts);
	414	return err;
acb45439 RK	415	}
	416
	417	static void ucb1x00_ts_remove(struct ucb1x00_dev *dev)
	418	{
	419	struct ucb1x00_ts *ts = dev->priv;
bd622663 DT	420
bd622663 DT	421	input_unregister_device(ts->idev);
acb45439 RK	422	kfree(ts);
	423	}
	424
	425	static struct ucb1x00_driver ucb1x00_ts_driver = {
	426	.add = ucb1x00_ts_add,
	427	.remove = ucb1x00_ts_remove,
	428	.resume = ucb1x00_ts_resume,
	429	};
	430
	431	static int __init ucb1x00_ts_init(void)
	432	{
	433	return ucb1x00_register_driver(&ucb1x00_ts_driver);
	434	}
	435
	436	static void __exit ucb1x00_ts_exit(void)
	437	{
	438	ucb1x00_unregister_driver(&ucb1x00_ts_driver);
	439	}
	440
	441	module_param(adcsync, int, 0444);
	442	module_init(ucb1x00_ts_init);
	443	module_exit(ucb1x00_ts_exit);
	444
	445	MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
	446	MODULE_DESCRIPTION("UCB1x00 touchscreen driver");
	447	MODULE_LICENSE("GPL");