[deliverable/linux.git] / drivers / input / touchscreen / mc13783_ts.c

/*
 * Driver for the Freescale Semiconductor MC13783 touchscreen.
 *
 * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
 * Copyright (C) 2009 Sascha Hauer, Pengutronix
 *
 * Initial development of this code was funded by
 * Phytec Messtechnik GmbH, http://www.phytec.de/
 *
 * 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/platform_device.h>
#include <linux/mfd/mc13783.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/input.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/init.h>

#define MC13783_TS_NAME	"mc13783-ts"

#define DEFAULT_SAMPLE_TOLERANCE 300

static unsigned int sample_tolerance = DEFAULT_SAMPLE_TOLERANCE;
module_param(sample_tolerance, uint, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(sample_tolerance,
		"If the minimal and maximal value read out for one axis (out "
		"of three) differ by this value (default: "
		__stringify(DEFAULT_SAMPLE_TOLERANCE) ") or more, the reading "
		"is supposed to be wrong and is discarded.  Set to 0 to "
		"disable this check.");

struct mc13783_ts_priv {
	struct input_dev *idev;
	struct mc13xxx *mc13xxx;
	struct delayed_work work;
	struct workqueue_struct *workq;
	unsigned int sample[4];
	struct mc13xxx_ts_platform_data *touch;
};

static irqreturn_t mc13783_ts_handler(int irq, void *data)
{
	struct mc13783_ts_priv *priv = data;

	mc13xxx_irq_ack(priv->mc13xxx, irq);

	/*
	 * Kick off reading coordinates. Note that if work happens already
	 * be queued for future execution (it rearms itself) it will not
	 * be rescheduled for immediate execution here. However the rearm
	 * delay is HZ / 50 which is acceptable.
	 */
	queue_delayed_work(priv->workq, &priv->work, 0);

	return IRQ_HANDLED;
}

#define sort3(a0, a1, a2) ({						\
		if (a0 > a1)						\
			swap(a0, a1);					\
		if (a1 > a2)						\
			swap(a1, a2);					\
		if (a0 > a1)						\
			swap(a0, a1);					\
		})

static void mc13783_ts_report_sample(struct mc13783_ts_priv *priv)
{
	struct input_dev *idev = priv->idev;
	int x0, x1, x2, y0, y1, y2;
	int cr0, cr1;

	/*
	 * the values are 10-bit wide only, but the two least significant
	 * bits are for future 12 bit use and reading yields 0
	 */
	x0 = priv->sample[0] & 0xfff;
	x1 = priv->sample[1] & 0xfff;
	x2 = priv->sample[2] & 0xfff;
	y0 = priv->sample[3] & 0xfff;
	y1 = (priv->sample[0] >> 12) & 0xfff;
	y2 = (priv->sample[1] >> 12) & 0xfff;
	cr0 = (priv->sample[2] >> 12) & 0xfff;
	cr1 = (priv->sample[3] >> 12) & 0xfff;

	dev_dbg(&idev->dev,
		"x: (% 4d,% 4d,% 4d) y: (% 4d, % 4d,% 4d) cr: (% 4d, % 4d)\n",
		x0, x1, x2, y0, y1, y2, cr0, cr1);

	sort3(x0, x1, x2);
	sort3(y0, y1, y2);

	cr0 = (cr0 + cr1) / 2;

	if (!cr0 || !sample_tolerance ||
			(x2 - x0 < sample_tolerance &&
			 y2 - y0 < sample_tolerance)) {
		/* report the median coordinate and average pressure */
		if (cr0) {
			input_report_abs(idev, ABS_X, x1);
			input_report_abs(idev, ABS_Y, y1);

			dev_dbg(&idev->dev, "report (%d, %d, %d)\n",
					x1, y1, 0x1000 - cr0);
			queue_delayed_work(priv->workq, &priv->work, HZ / 50);
		} else
			dev_dbg(&idev->dev, "report release\n");

		input_report_abs(idev, ABS_PRESSURE,
				cr0 ? 0x1000 - cr0 : cr0);
		input_report_key(idev, BTN_TOUCH, cr0);
		input_sync(idev);
	} else
		dev_dbg(&idev->dev, "discard event\n");
}

static void mc13783_ts_work(struct work_struct *work)
{
	struct mc13783_ts_priv *priv =
		container_of(work, struct mc13783_ts_priv, work.work);
	unsigned int mode = MC13XXX_ADC_MODE_TS;
	unsigned int channel = 12;

	if (mc13xxx_adc_do_conversion(priv->mc13xxx,
				mode, channel,
				priv->touch->ato, priv->touch->atox,
				priv->sample) == 0)
		mc13783_ts_report_sample(priv);
}

static int mc13783_ts_open(struct input_dev *dev)
{
	struct mc13783_ts_priv *priv = input_get_drvdata(dev);
	int ret;

	mc13xxx_lock(priv->mc13xxx);

	mc13xxx_irq_ack(priv->mc13xxx, MC13XXX_IRQ_TS);

	ret = mc13xxx_irq_request(priv->mc13xxx, MC13XXX_IRQ_TS,
		mc13783_ts_handler, MC13783_TS_NAME, priv);
	if (ret)
		goto out;

	ret = mc13xxx_reg_rmw(priv->mc13xxx, MC13XXX_ADC0,
			MC13XXX_ADC0_TSMOD_MASK, MC13XXX_ADC0_TSMOD0);
	if (ret)
		mc13xxx_irq_free(priv->mc13xxx, MC13XXX_IRQ_TS, priv);
out:
	mc13xxx_unlock(priv->mc13xxx);
	return ret;
}

static void mc13783_ts_close(struct input_dev *dev)
{
	struct mc13783_ts_priv *priv = input_get_drvdata(dev);

	mc13xxx_lock(priv->mc13xxx);
	mc13xxx_reg_rmw(priv->mc13xxx, MC13XXX_ADC0,
			MC13XXX_ADC0_TSMOD_MASK, 0);
	mc13xxx_irq_free(priv->mc13xxx, MC13XXX_IRQ_TS, priv);
	mc13xxx_unlock(priv->mc13xxx);

	cancel_delayed_work_sync(&priv->work);
}

static int __init mc13783_ts_probe(struct platform_device *pdev)
{
	struct mc13783_ts_priv *priv;
	struct input_dev *idev;
	int ret = -ENOMEM;

	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
	idev = input_allocate_device();
	if (!priv || !idev)
		goto err_free_mem;

	INIT_DELAYED_WORK(&priv->work, mc13783_ts_work);
	priv->mc13xxx = dev_get_drvdata(pdev->dev.parent);
	priv->idev = idev;
	priv->touch = dev_get_platdata(&pdev->dev);
	if (!priv->touch) {
		dev_err(&pdev->dev, "missing platform data\n");
		ret = -ENODEV;
		goto err_free_mem;
	}

	/*
	 * We need separate workqueue because mc13783_adc_do_conversion
	 * uses keventd and thus would deadlock.
	 */
	priv->workq = create_singlethread_workqueue("mc13783_ts");
	if (!priv->workq)
		goto err_free_mem;

	idev->name = MC13783_TS_NAME;
	idev->dev.parent = &pdev->dev;

	idev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
	idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
	input_set_abs_params(idev, ABS_X, 0, 0xfff, 0, 0);
	input_set_abs_params(idev, ABS_Y, 0, 0xfff, 0, 0);
	input_set_abs_params(idev, ABS_PRESSURE, 0, 0xfff, 0, 0);

	idev->open = mc13783_ts_open;
	idev->close = mc13783_ts_close;

	input_set_drvdata(idev, priv);

	ret = input_register_device(priv->idev);
	if (ret) {
		dev_err(&pdev->dev,
			"register input device failed with %d\n", ret);
		goto err_destroy_wq;
	}

	platform_set_drvdata(pdev, priv);
	return 0;

err_destroy_wq:
	destroy_workqueue(priv->workq);
err_free_mem:
	input_free_device(idev);
	kfree(priv);
	return ret;
}

static int mc13783_ts_remove(struct platform_device *pdev)
{
	struct mc13783_ts_priv *priv = platform_get_drvdata(pdev);

	destroy_workqueue(priv->workq);
	input_unregister_device(priv->idev);
	kfree(priv);

	return 0;
}

static struct platform_driver mc13783_ts_driver = {
	.remove		= mc13783_ts_remove,
	.driver		= {
		.owner	= THIS_MODULE,
		.name	= MC13783_TS_NAME,
	},
};

module_platform_driver_probe(mc13783_ts_driver, mc13783_ts_probe);

MODULE_DESCRIPTION("MC13783 input touchscreen driver");
MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:" MC13783_TS_NAME);
Commit	Line	Data
d201fd5d SH	1	/*
	2	* Driver for the Freescale Semiconductor MC13783 touchscreen.
	3	*
	4	* Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
	5	* Copyright (C) 2009 Sascha Hauer, Pengutronix
	6	*
	7	* Initial development of this code was funded by
	8	* Phytec Messtechnik GmbH, http://www.phytec.de/
	9	*
	10	* This program is free software; you can redistribute it and/or modify it
	11	* under the terms of the GNU General Public License version 2 as published by
	12	* the Free Software Foundation.
	13	*/
	14	#include <linux/platform_device.h>
	15	#include <linux/mfd/mc13783.h>
	16	#include <linux/kernel.h>
	17	#include <linux/module.h>
	18	#include <linux/input.h>
	19	#include <linux/sched.h>
5a0e3ad6	20	#include <linux/slab.h>
d201fd5d SH	21	#include <linux/init.h>
	22
	23	#define MC13783_TS_NAME "mc13783-ts"
	24
	25	#define DEFAULT_SAMPLE_TOLERANCE 300
	26
	27	static unsigned int sample_tolerance = DEFAULT_SAMPLE_TOLERANCE;
	28	module_param(sample_tolerance, uint, S_IRUGO \| S_IWUSR);
	29	MODULE_PARM_DESC(sample_tolerance,
	30	"If the minimal and maximal value read out for one axis (out "
	31	"of three) differ by this value (default: "
	32	__stringify(DEFAULT_SAMPLE_TOLERANCE) ") or more, the reading "
	33	"is supposed to be wrong and is discarded. Set to 0 to "
	34	"disable this check.");
	35
	36	struct mc13783_ts_priv {
	37	struct input_dev *idev;
8dd93eee	38	struct mc13xxx *mc13xxx;
d201fd5d SH	39	struct delayed_work work;
	40	struct workqueue_struct *workq;
	41	unsigned int sample[4];
1039d762	42	struct mc13xxx_ts_platform_data *touch;
d201fd5d SH	43	};
	44
	45	static irqreturn_t mc13783_ts_handler(int irq, void *data)
	46	{
	47	struct mc13783_ts_priv *priv = data;
	48
8dd93eee	49	mc13xxx_irq_ack(priv->mc13xxx, irq);
d201fd5d SH	50
	51	/*
	52	* Kick off reading coordinates. Note that if work happens already
	53	* be queued for future execution (it rearms itself) it will not
	54	* be rescheduled for immediate execution here. However the rearm
	55	* delay is HZ / 50 which is acceptable.
	56	*/
	57	queue_delayed_work(priv->workq, &priv->work, 0);
	58
	59	return IRQ_HANDLED;
	60	}
	61
	62	#define sort3(a0, a1, a2) ({ \
	63	if (a0 > a1) \
	64	swap(a0, a1); \
	65	if (a1 > a2) \
	66	swap(a1, a2); \
	67	if (a0 > a1) \
	68	swap(a0, a1); \
	69	})
	70
	71	static void mc13783_ts_report_sample(struct mc13783_ts_priv *priv)
	72	{
	73	struct input_dev *idev = priv->idev;
	74	int x0, x1, x2, y0, y1, y2;
	75	int cr0, cr1;
	76
	77	/*
	78	* the values are 10-bit wide only, but the two least significant
	79	* bits are for future 12 bit use and reading yields 0
	80	*/
	81	x0 = priv->sample[0] & 0xfff;
	82	x1 = priv->sample[1] & 0xfff;
	83	x2 = priv->sample[2] & 0xfff;
	84	y0 = priv->sample[3] & 0xfff;
	85	y1 = (priv->sample[0] >> 12) & 0xfff;
	86	y2 = (priv->sample[1] >> 12) & 0xfff;
	87	cr0 = (priv->sample[2] >> 12) & 0xfff;
	88	cr1 = (priv->sample[3] >> 12) & 0xfff;
	89
	90	dev_dbg(&idev->dev,
	91	"x: (% 4d,% 4d,% 4d) y: (% 4d, % 4d,% 4d) cr: (% 4d, % 4d)\n",
	92	x0, x1, x2, y0, y1, y2, cr0, cr1);
	93
	94	sort3(x0, x1, x2);
	95	sort3(y0, y1, y2);
	96
	97	cr0 = (cr0 + cr1) / 2;
	98
	99	if (!cr0 \|\| !sample_tolerance \|\|
	100	(x2 - x0 < sample_tolerance &&
	101	y2 - y0 < sample_tolerance)) {
	102	/* report the median coordinate and average pressure */
	103	if (cr0) {
	104	input_report_abs(idev, ABS_X, x1);
	105	input_report_abs(idev, ABS_Y, y1);
	106
	107	dev_dbg(&idev->dev, "report (%d, %d, %d)\n",
	108	x1, y1, 0x1000 - cr0);
	109	queue_delayed_work(priv->workq, &priv->work, HZ / 50);
	110	} else
	111	dev_dbg(&idev->dev, "report release\n");
	112
	113	input_report_abs(idev, ABS_PRESSURE,
114	cr0 ? 0x1000 - cr0 : cr0);
115	input_report_key(idev, BTN_TOUCH, cr0);
116	input_sync(idev);
117	} else
118	dev_dbg(&idev->dev, "discard event\n");
119	}
120
121	static void mc13783_ts_work(struct work_struct *work)
122	{
123	struct mc13783_ts_priv *priv =
124	container_of(work, struct mc13783_ts_priv, work.work);
8dd93eee	125	unsigned int mode = MC13XXX_ADC_MODE_TS;
d201fd5d SH	126	unsigned int channel = 12;
d201fd5d SH	127
8dd93eee	128	if (mc13xxx_adc_do_conversion(priv->mc13xxx,
1039d762 MT	129	mode, channel,
	130	priv->touch->ato, priv->touch->atox,
	131	priv->sample) == 0)
d201fd5d SH	132	mc13783_ts_report_sample(priv);
	133	}
	134
	135	static int mc13783_ts_open(struct input_dev *dev)
	136	{
	137	struct mc13783_ts_priv *priv = input_get_drvdata(dev);
	138	int ret;
	139
8dd93eee	140	mc13xxx_lock(priv->mc13xxx);
d201fd5d	141
8dd93eee	142	mc13xxx_irq_ack(priv->mc13xxx, MC13XXX_IRQ_TS);
d201fd5d	143
8dd93eee	144	ret = mc13xxx_irq_request(priv->mc13xxx, MC13XXX_IRQ_TS,
d201fd5d SH	145	mc13783_ts_handler, MC13783_TS_NAME, priv);
	146	if (ret)
	147	goto out;
	148
8dd93eee UKK	149	ret = mc13xxx_reg_rmw(priv->mc13xxx, MC13XXX_ADC0,
8dd93eee UKK	150	MC13XXX_ADC0_TSMOD_MASK, MC13XXX_ADC0_TSMOD0);
d201fd5d	151	if (ret)
8dd93eee	152	mc13xxx_irq_free(priv->mc13xxx, MC13XXX_IRQ_TS, priv);
d201fd5d	153	out:
8dd93eee	154	mc13xxx_unlock(priv->mc13xxx);
d201fd5d SH	155	return ret;
	156	}
	157
	158	static void mc13783_ts_close(struct input_dev *dev)
	159	{
	160	struct mc13783_ts_priv *priv = input_get_drvdata(dev);
	161
8dd93eee UKK	162	mc13xxx_lock(priv->mc13xxx);
	163	mc13xxx_reg_rmw(priv->mc13xxx, MC13XXX_ADC0,
	164	MC13XXX_ADC0_TSMOD_MASK, 0);
	165	mc13xxx_irq_free(priv->mc13xxx, MC13XXX_IRQ_TS, priv);
	166	mc13xxx_unlock(priv->mc13xxx);
d201fd5d SH	167
	168	cancel_delayed_work_sync(&priv->work);
	169	}
	170
	171	static int __init mc13783_ts_probe(struct platform_device *pdev)
	172	{
	173	struct mc13783_ts_priv *priv;
	174	struct input_dev *idev;
	175	int ret = -ENOMEM;
	176
	177	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
	178	idev = input_allocate_device();
	179	if (!priv \|\| !idev)
	180	goto err_free_mem;
	181
	182	INIT_DELAYED_WORK(&priv->work, mc13783_ts_work);
8dd93eee	183	priv->mc13xxx = dev_get_drvdata(pdev->dev.parent);
d201fd5d	184	priv->idev = idev;
1039d762 MT	185	priv->touch = dev_get_platdata(&pdev->dev);
	186	if (!priv->touch) {
	187	dev_err(&pdev->dev, "missing platform data\n");
	188	ret = -ENODEV;
	189	goto err_free_mem;
	190	}
d201fd5d SH	191
	192	/*
	193	* We need separate workqueue because mc13783_adc_do_conversion
	194	* uses keventd and thus would deadlock.
	195	*/
	196	priv->workq = create_singlethread_workqueue("mc13783_ts");
	197	if (!priv->workq)
	198	goto err_free_mem;
	199
	200	idev->name = MC13783_TS_NAME;
	201	idev->dev.parent = &pdev->dev;
	202
	203	idev->evbit[0] = BIT_MASK(EV_KEY) \| BIT_MASK(EV_ABS);
	204	idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
	205	input_set_abs_params(idev, ABS_X, 0, 0xfff, 0, 0);
	206	input_set_abs_params(idev, ABS_Y, 0, 0xfff, 0, 0);
	207	input_set_abs_params(idev, ABS_PRESSURE, 0, 0xfff, 0, 0);
	208
	209	idev->open = mc13783_ts_open;
	210	idev->close = mc13783_ts_close;
	211
	212	input_set_drvdata(idev, priv);
	213
	214	ret = input_register_device(priv->idev);
	215	if (ret) {
	216	dev_err(&pdev->dev,
	217	"register input device failed with %d\n", ret);
	218	goto err_destroy_wq;
	219	}
	220
	221	platform_set_drvdata(pdev, priv);
	222	return 0;
	223
	224	err_destroy_wq:
	225	destroy_workqueue(priv->workq);
	226	err_free_mem:
	227	input_free_device(idev);
	228	kfree(priv);
	229	return ret;
	230	}
	231
e2619cf7	232	static int mc13783_ts_remove(struct platform_device *pdev)
d201fd5d SH	233	{
	234	struct mc13783_ts_priv *priv = platform_get_drvdata(pdev);
	235
d201fd5d SH	236	destroy_workqueue(priv->workq);
	237	input_unregister_device(priv->idev);
	238	kfree(priv);
	239
	240	return 0;
	241	}
	242
	243	static struct platform_driver mc13783_ts_driver = {
1cb0aa88	244	.remove = mc13783_ts_remove,
d201fd5d SH	245	.driver = {
	246	.owner = THIS_MODULE,
	247	.name = MC13783_TS_NAME,
	248	},
	249	};
d3d25808	250
38a46eb8	251	module_platform_driver_probe(mc13783_ts_driver, mc13783_ts_probe);
d201fd5d SH	252
	253	MODULE_DESCRIPTION("MC13783 input touchscreen driver");
	254	MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
	255	MODULE_LICENSE("GPL v2");
	256	MODULE_ALIAS("platform:" MC13783_TS_NAME);