Release 4.11 drivers/input/touchscreen/tsc2007.c

/*
 * drivers/input/touchscreen/tsc2007.c
 *
 * Copyright (c) 2008 MtekVision Co., Ltd.
 *      Kwangwoo Lee <kwlee@mtekvision.com>
 *
 * Using code from:
 *  - ads7846.c
 *      Copyright (c) 2005 David Brownell
 *      Copyright (c) 2006 Nokia Corporation
 *  - corgi_ts.c
 *      Copyright (C) 2004-2005 Richard Purdie
 *  - omap_ts.[hc], ads7846.h, ts_osk.c
 *      Copyright (C) 2002 MontaVista Software
 *      Copyright (C) 2004 Texas Instruments
 *      Copyright (C) 2005 Dirk Behme
 *
 *  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/slab.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/i2c.h>
#include <linux/i2c/tsc2007.h>
#include <linux/of_device.h>
#include <linux/of.h>
#include <linux/of_gpio.h>


#define TSC2007_MEASURE_TEMP0		(0x0 << 4)

#define TSC2007_MEASURE_AUX		(0x2 << 4)

#define TSC2007_MEASURE_TEMP1		(0x4 << 4)

#define TSC2007_ACTIVATE_XN		(0x8 << 4)

#define TSC2007_ACTIVATE_YN		(0x9 << 4)

#define TSC2007_ACTIVATE_YP_XN		(0xa << 4)

#define TSC2007_SETUP			(0xb << 4)

#define TSC2007_MEASURE_X		(0xc << 4)

#define TSC2007_MEASURE_Y		(0xd << 4)

#define TSC2007_MEASURE_Z1		(0xe << 4)

#define TSC2007_MEASURE_Z2		(0xf << 4)


#define TSC2007_POWER_OFF_IRQ_EN	(0x0 << 2)

#define TSC2007_ADC_ON_IRQ_DIS0		(0x1 << 2)

#define TSC2007_ADC_OFF_IRQ_EN		(0x2 << 2)

#define TSC2007_ADC_ON_IRQ_DIS1		(0x3 << 2)


#define TSC2007_12BIT			(0x0 << 1)

#define TSC2007_8BIT			(0x1 << 1)


#define	MAX_12BIT			((1 << 12) - 1)


#define ADC_ON_12BIT	(TSC2007_12BIT | TSC2007_ADC_ON_IRQ_DIS0)


#define READ_Y		(ADC_ON_12BIT | TSC2007_MEASURE_Y)

#define READ_Z1		(ADC_ON_12BIT | TSC2007_MEASURE_Z1)

#define READ_Z2		(ADC_ON_12BIT | TSC2007_MEASURE_Z2)

#define READ_X		(ADC_ON_12BIT | TSC2007_MEASURE_X)

#define PWRDOWN		(TSC2007_12BIT | TSC2007_POWER_OFF_IRQ_EN)


struct ts_event {
	
u16	x;
	
u16	y;
	

u16	z1, z2;
};


struct tsc2007 {
	
struct input_dev	*input;
	
char			phys[32];

	
struct i2c_client	*client;

	
u16			model;
	
u16			x_plate_ohms;
	
u16			max_rt;
	
unsigned long		poll_period; /* in jiffies */
	
int			fuzzx;
	
int			fuzzy;
	
int			fuzzz;

	
unsigned		gpio;
	
int			irq;

	
wait_queue_head_t	wait;
	
bool			stopped;

	
int			(*get_pendown_state)(struct device *);
	
void			(*clear_penirq)(void);
};



static inline int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd)
{
	s32 data;
	u16 val;

	data = i2c_smbus_read_word_data(tsc->client, cmd);
	if (data < 0) {
		dev_err(&tsc->client->dev, "i2c io error: %d\n", data);
		return data;
	}

	/* The protocol and raw data format from i2c interface:
         * S Addr Wr [A] Comm [A] S Addr Rd [A] [DataLow] A [DataHigh] NA P
         * Where DataLow has [D11-D4], DataHigh has [D3-D0 << 4 | Dummy 4bit].
         */
	val = swab16(data) >> 4;

	dev_dbg(&tsc->client->dev, "data: 0x%x, val: 0x%x\n", data, val);

	return val;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Kwangwoo Lee
86
100.00%
1
100.00%
Total
86
100.00%
1
100.00%



static void tsc2007_read_values(struct tsc2007 *tsc, struct ts_event *tc)
{
	/* y- still on; turn on only y+ (and ADC) */
	tc->y = tsc2007_xfer(tsc, READ_Y);

	/* turn y- off, x+ on, then leave in lowpower */
	tc->x = tsc2007_xfer(tsc, READ_X);

	/* turn y+ off, x- on; we'll use formula #1 */
	tc->z1 = tsc2007_xfer(tsc, READ_Z1);
	tc->z2 = tsc2007_xfer(tsc, READ_Z2);

	/* Prepare for next touch reading - power down ADC, enable PENIRQ */
	tsc2007_xfer(tsc, PWRDOWN);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Dmitry Torokhov
52
73.24%
1
50.00%
Kwangwoo Lee
19
26.76%
1
50.00%
Total
71
100.00%
2
100.00%



static u32 tsc2007_calculate_pressure(struct tsc2007 *tsc, struct ts_event *tc)
{
	u32 rt = 0;

	/* range filtering */
	if (tc->x == MAX_12BIT)
		tc->x = 0;

	if (likely(tc->x && tc->z1)) {
		/* compute touch pressure resistance using equation #1 */
		rt = tc->z2 - tc->z1;
		rt *= tc->x;
		rt *= tsc->x_plate_ohms;
		rt /= tc->z1;
		rt = (rt + 2047) >> 12;
	}

	return rt;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Kwangwoo Lee
52
55.91%
1
50.00%
Dmitry Torokhov
41
44.09%
1
50.00%
Total
93
100.00%
2
100.00%



static bool tsc2007_is_pen_down(struct tsc2007 *ts)
{
	/*
         * NOTE: We can't rely on the pressure to determine the pen down
         * state, even though this controller has a pressure sensor.
         * The pressure value can fluctuate for quite a while after
         * lifting the pen and in some cases may not even settle at the
         * expected value.
         *
         * The only safe way to check for the pen up condition is in the
         * work function by reading the pen signal state (it's a GPIO
         * and IRQ). Unfortunately such callback is not always available,
         * in that case we assume that the pen is down and expect caller
         * to fall back on the pressure reading.
         */

	if (!ts->get_pendown_state)
		return true;

	return ts->get_pendown_state(&ts->client->dev);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Dmitry Torokhov
27
77.14%
2
66.67%
Denis Carikli
8
22.86%
1
33.33%
Total
35
100.00%
3
100.00%



static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
{
	struct tsc2007 *ts = handle;
	struct input_dev *input = ts->input;
	struct ts_event tc;
	u32 rt;

	while (!ts->stopped && tsc2007_is_pen_down(ts)) {

		/* pen is down, continue with the measurement */
		tsc2007_read_values(ts, &tc);

		rt = tsc2007_calculate_pressure(ts, &tc);

		if (!rt && !ts->get_pendown_state) {
			/*
                         * If pressure reported is 0 and we don't have
                         * callback to check pendown state, we have to
                         * assume that pen was lifted up.
                         */
			break;
		}

		if (rt <= ts->max_rt) {
			dev_dbg(&ts->client->dev,
				"DOWN point(%4d,%4d), pressure (%4u)\n",
				tc.x, tc.y, rt);

			input_report_key(input, BTN_TOUCH, 1);
			input_report_abs(input, ABS_X, tc.x);
			input_report_abs(input, ABS_Y, tc.y);
			input_report_abs(input, ABS_PRESSURE, rt);

			input_sync(input);

		} else {
			/*
                         * Sample found inconsistent by debouncing or pressure is
                         * beyond the maximum. Don't report it to user space,
                         * repeat at least once more the measurement.
                         */
			dev_dbg(&ts->client->dev, "ignored pressure %d\n", rt);
		}

		wait_event_timeout(ts->wait, ts->stopped, ts->poll_period);
	}

	dev_dbg(&ts->client->dev, "UP\n");

	input_report_key(input, BTN_TOUCH, 0);
	input_report_abs(input, ABS_PRESSURE, 0);
	input_sync(input);

	if (ts->clear_penirq)
		ts->clear_penirq();

	return IRQ_HANDLED;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Dmitry Torokhov
149
61.57%
3
42.86%
Kwangwoo Lee
88
36.36%
1
14.29%
Thierry Reding
4
1.65%
2
28.57%
Denis Carikli
1
0.41%
1
14.29%
Total
242
100.00%
7
100.00%



static irqreturn_t tsc2007_hard_irq(int irq, void *handle)
{
	struct tsc2007 *ts = handle;

	if (tsc2007_is_pen_down(ts))
		return IRQ_WAKE_THREAD;

	if (ts->clear_penirq)
		ts->clear_penirq();

	return IRQ_HANDLED;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Kwangwoo Lee
39
88.64%
1
33.33%
Dmitry Torokhov
4
9.09%
1
33.33%
Denis Carikli
1
2.27%
1
33.33%
Total
44
100.00%
3
100.00%



static void tsc2007_stop(struct tsc2007 *ts)
{
	ts->stopped = true;
	mb();
	wake_up(&ts->wait);

	disable_irq(ts->irq);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Dmitry Torokhov
35
100.00%
3
100.00%
Total
35
100.00%
3
100.00%



static int tsc2007_open(struct input_dev *input_dev)
{
	struct tsc2007 *ts = input_get_drvdata(input_dev);
	int err;

	ts->stopped = false;
	mb();

	enable_irq(ts->irq);

	/* Prepare for touch readings - power down ADC and enable PENIRQ */
	err = tsc2007_xfer(ts, PWRDOWN);
	if (err < 0) {
		tsc2007_stop(ts);
		return err;
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Dmitry Torokhov
69
100.00%
2
100.00%
Total
69
100.00%
2
100.00%



static void tsc2007_close(struct input_dev *input_dev)
{
	struct tsc2007 *ts = input_get_drvdata(input_dev);

	tsc2007_stop(ts);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Dmitry Torokhov
26
100.00%
3
100.00%
Total
26
100.00%
3
100.00%

#ifdef CONFIG_OF


static int tsc2007_get_pendown_state_gpio(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct tsc2007 *ts = i2c_get_clientdata(client);

	return !gpio_get_value(ts->gpio);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Denis Carikli
31
77.50%
1
50.00%
Kwangwoo Lee
9
22.50%
1
50.00%
Total
40
100.00%
2
100.00%



static int tsc2007_probe_dt(struct i2c_client *client, struct tsc2007 *ts)
{
	struct device_node *np = client->dev.of_node;
	u32 val32;
	u64 val64;

	if (!np) {
		dev_err(&client->dev, "missing device tree data\n");
		return -EINVAL;
	}

	if (!of_property_read_u32(np, "ti,max-rt", &val32))
		ts->max_rt = val32;
	else
		ts->max_rt = MAX_12BIT;

	if (!of_property_read_u32(np, "ti,fuzzx", &val32))
		ts->fuzzx = val32;

	if (!of_property_read_u32(np, "ti,fuzzy", &val32))
		ts->fuzzy = val32;

	if (!of_property_read_u32(np, "ti,fuzzz", &val32))
		ts->fuzzz = val32;

	if (!of_property_read_u64(np, "ti,poll-period", &val64))
		ts->poll_period = msecs_to_jiffies(val64);
	else
		ts->poll_period = msecs_to_jiffies(1);

	if (!of_property_read_u32(np, "ti,x-plate-ohms", &val32)) {
		ts->x_plate_ohms = val32;
	} else {
		dev_err(&client->dev, "missing ti,x-plate-ohms devicetree property.");
		return -EINVAL;
	}

	ts->gpio = of_get_gpio(np, 0);
	if (gpio_is_valid(ts->gpio))
		ts->get_pendown_state = tsc2007_get_pendown_state_gpio;
	else
		dev_warn(&client->dev,
			 "GPIO not specified in DT (of_get_gpio returned %d)\n",
			 ts->gpio);

	return 0;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Denis Carikli
160
63.75%
1
14.29%
Kwangwoo Lee
71
28.29%
1
14.29%
Dmitry Torokhov
7
2.79%
1
14.29%
Thierry Reding
7
2.79%
3
42.86%
Aaron Sierra
6
2.39%
1
14.29%
Total
251
100.00%
7
100.00%

#else


static int tsc2007_probe_dt(struct i2c_client *client, struct tsc2007 *ts)
{
	dev_err(&client->dev, "platform data is required!\n");
	return -EINVAL;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Denis Carikli
30
100.00%
1
100.00%
Total
30
100.00%
1
100.00%

#endif



static int tsc2007_probe_pdev(struct i2c_client *client, struct tsc2007 *ts,
			      const struct tsc2007_platform_data *pdata,
			      const struct i2c_device_id *id)
{
	ts->model             = pdata->model;
	ts->x_plate_ohms      = pdata->x_plate_ohms;
	ts->max_rt            = pdata->max_rt ? : MAX_12BIT;
	ts->poll_period       = msecs_to_jiffies(pdata->poll_period ? : 1);
	ts->get_pendown_state = pdata->get_pendown_state;
	ts->clear_penirq      = pdata->clear_penirq;
	ts->fuzzx             = pdata->fuzzx;
	ts->fuzzy             = pdata->fuzzy;
	ts->fuzzz             = pdata->fuzzz;

	if (pdata->x_plate_ohms == 0) {
		dev_err(&client->dev, "x_plate_ohms is not set up in platform data");
		return -EINVAL;
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Denis Carikli
92
67.65%
1
20.00%
Philip Rakity
19
13.97%
1
20.00%
Kwangwoo Lee
14
10.29%
1
20.00%
Thierry Reding
8
5.88%
1
20.00%
Aaron Sierra
3
2.21%
1
20.00%
Total
136
100.00%
5
100.00%



static void tsc2007_call_exit_platform_hw(void *data)
{
	struct device *dev = data;
	const struct tsc2007_platform_data *pdata = dev_get_platdata(dev);

	pdata->exit_platform_hw();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Dmitry Torokhov
33
100.00%
1
100.00%
Total
33
100.00%
1
100.00%



static int tsc2007_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	const struct tsc2007_platform_data *pdata = dev_get_platdata(&client->dev);
	struct tsc2007 *ts;
	struct input_dev *input_dev;
	int err;

	if (!i2c_check_functionality(client->adapter,
				     I2C_FUNC_SMBUS_READ_WORD_DATA))
		return -EIO;

	ts = devm_kzalloc(&client->dev, sizeof(struct tsc2007), GFP_KERNEL);
	if (!ts)
		return -ENOMEM;

	if (pdata)
		err = tsc2007_probe_pdev(client, ts, pdata, id);
	else
		err = tsc2007_probe_dt(client, ts);
	if (err)
		return err;

	input_dev = devm_input_allocate_device(&client->dev);
	if (!input_dev)
		return -ENOMEM;

	i2c_set_clientdata(client, ts);

	ts->client = client;
	ts->irq = client->irq;
	ts->input = input_dev;
	init_waitqueue_head(&ts->wait);

	snprintf(ts->phys, sizeof(ts->phys),
		 "%s/input0", dev_name(&client->dev));

	input_dev->name = "TSC2007 Touchscreen";
	input_dev->phys = ts->phys;
	input_dev->id.bustype = BUS_I2C;

	input_dev->open = tsc2007_open;
	input_dev->close = tsc2007_close;

	input_set_drvdata(input_dev, ts);

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

	input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, ts->fuzzx, 0);
	input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, ts->fuzzy, 0);
	input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT,
			     ts->fuzzz, 0);

	if (pdata) {
		if (pdata->exit_platform_hw) {
			err = devm_add_action(&client->dev,
					      tsc2007_call_exit_platform_hw,
					      &client->dev);
			if (err) {
				dev_err(&client->dev,
					"Failed to register exit_platform_hw action, %d\n",
					err);
				return err;
			}
		}

		if (pdata->init_platform_hw)
			pdata->init_platform_hw();
	}

	err = devm_request_threaded_irq(&client->dev, ts->irq,
					tsc2007_hard_irq, tsc2007_soft_irq,
					IRQF_ONESHOT,
					client->dev.driver->name, ts);
	if (err) {
		dev_err(&client->dev, "Failed to request irq %d: %d\n",
			ts->irq, err);
		return err;
	}

	tsc2007_stop(ts);

	err = input_register_device(input_dev);
	if (err) {
		dev_err(&client->dev,
			"Failed to register input device: %d\n", err);
		return err;
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Kwangwoo Lee
175
36.69%
1
8.33%
Denis Carikli
171
35.85%
1
8.33%
Dmitry Torokhov
108
22.64%
4
33.33%
Richard Röjfors
12
2.52%
3
25.00%
Thierry Reding
6
1.26%
1
8.33%
Kay Sievers
4
0.84%
1
8.33%
Philip Rakity
1
0.21%
1
8.33%
Total
477
100.00%
12
100.00%


static const struct i2c_device_id tsc2007_idtable[] = {
	{ "tsc2007", 0 },
	{ }
};

MODULE_DEVICE_TABLE(i2c, tsc2007_idtable);

#ifdef CONFIG_OF

static const struct of_device_id tsc2007_of_match[] = {
	{ .compatible = "ti,tsc2007" },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, tsc2007_of_match);
#endif


static struct i2c_driver tsc2007_driver = {
	.driver = {
		.name	= "tsc2007",
		.of_match_table = of_match_ptr(tsc2007_of_match),
        },
	.id_table	= tsc2007_idtable,
	.probe		= tsc2007_probe,
};


module_i2c_driver(tsc2007_driver);

MODULE_AUTHOR("Kwangwoo Lee <kwlee@mtekvision.com>");
MODULE_DESCRIPTION("TSC2007 TouchScreen Driver");
MODULE_LICENSE("GPL");
Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
Kwangwoo Lee
798
39.86%
1
5.00%
Denis Carikli
566
28.27%
1
5.00%
Dmitry Torokhov
557
27.82%
5
25.00%
Thierry Reding
32
1.60%
5
25.00%
Philip Rakity
20
1.00%
1
5.00%
Richard Röjfors
12
0.60%
3
15.00%
Aaron Sierra
10
0.50%
1
5.00%
Kay Sievers
4
0.20%
1
5.00%
Axel Lin
2
0.10%
1
5.00%
Márton Németh
1
0.05%
1
5.00%
Total
2002
100.00%
20
100.00%
Directory: drivers/input/touchscreen

Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.