1/*
2 * drivers/input/touchscreen/jornada720_ts.c
3 *
4 * Copyright (C) 2007 Kristoffer Ericson <Kristoffer.Ericson@gmail.com>
5 *
6 *  Copyright (C) 2006 Filip Zyzniewski <filip.zyzniewski@tefnet.pl>
7 *  based on HP Jornada 56x touchscreen driver by Alex Lange <chicken@handhelds.org>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 *
13 * HP Jornada 710/720/729 Touchscreen Driver
14 */
15
16#include <linux/platform_device.h>
17#include <linux/input.h>
18#include <linux/interrupt.h>
19#include <linux/module.h>
20#include <linux/slab.h>
21#include <linux/io.h>
22
23#include <mach/hardware.h>
24#include <mach/jornada720.h>
25#include <mach/irqs.h>
26
27MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson@gmail.com>");
28MODULE_DESCRIPTION("HP Jornada 710/720/728 touchscreen driver");
29MODULE_LICENSE("GPL v2");
30
31struct jornada_ts {
32	struct input_dev *dev;
33	int x_data[4];		/* X sample values */
34	int y_data[4];		/* Y sample values */
35};
36
37static void jornada720_ts_collect_data(struct jornada_ts *jornada_ts)
38{
39	/* 3 low word X samples */
40	jornada_ts->x_data[0] = jornada_ssp_byte(TXDUMMY);
41	jornada_ts->x_data[1] = jornada_ssp_byte(TXDUMMY);
42	jornada_ts->x_data[2] = jornada_ssp_byte(TXDUMMY);
43
44	/* 3 low word Y samples */
45	jornada_ts->y_data[0] = jornada_ssp_byte(TXDUMMY);
46	jornada_ts->y_data[1] = jornada_ssp_byte(TXDUMMY);
47	jornada_ts->y_data[2] = jornada_ssp_byte(TXDUMMY);
48
49	/* combined x samples bits */
50	jornada_ts->x_data[3] = jornada_ssp_byte(TXDUMMY);
51
52	/* combined y samples bits */
53	jornada_ts->y_data[3] = jornada_ssp_byte(TXDUMMY);
54}
55
56static int jornada720_ts_average(int coords[4])
57{
58	int coord, high_bits = coords[3];
59
60	coord  = coords[0] | ((high_bits & 0x03) << 8);
61	coord += coords[1] | ((high_bits & 0x0c) << 6);
62	coord += coords[2] | ((high_bits & 0x30) << 4);
63
64	return coord / 3;
65}
66
67static irqreturn_t jornada720_ts_interrupt(int irq, void *dev_id)
68{
69	struct platform_device *pdev = dev_id;
70	struct jornada_ts *jornada_ts = platform_get_drvdata(pdev);
71	struct input_dev *input = jornada_ts->dev;
72	int x, y;
73
74	/* If GPIO_GPIO9 is set to high then report pen up */
75	if (GPLR & GPIO_GPIO(9)) {
76		input_report_key(input, BTN_TOUCH, 0);
77		input_sync(input);
78	} else {
79		jornada_ssp_start();
80
81		/* proper reply to request is always TXDUMMY */
82		if (jornada_ssp_inout(GETTOUCHSAMPLES) == TXDUMMY) {
83			jornada720_ts_collect_data(jornada_ts);
84
85			x = jornada720_ts_average(jornada_ts->x_data);
86			y = jornada720_ts_average(jornada_ts->y_data);
87
88			input_report_key(input, BTN_TOUCH, 1);
89			input_report_abs(input, ABS_X, x);
90			input_report_abs(input, ABS_Y, y);
91			input_sync(input);
92		}
93
94		jornada_ssp_end();
95	}
96
97	return IRQ_HANDLED;
98}
99
100static int jornada720_ts_probe(struct platform_device *pdev)
101{
102	struct jornada_ts *jornada_ts;
103	struct input_dev *input_dev;
104	int error;
105
106	jornada_ts = devm_kzalloc(&pdev->dev, sizeof(*jornada_ts), GFP_KERNEL);
107	if (!jornada_ts)
108		return -ENOMEM;
109
110	input_dev = devm_input_allocate_device(&pdev->dev);
111	if (!input_dev)
112		return -ENOMEM;
113
114	platform_set_drvdata(pdev, jornada_ts);
115
116	jornada_ts->dev = input_dev;
117
118	input_dev->name = "HP Jornada 7xx Touchscreen";
119	input_dev->phys = "jornadats/input0";
120	input_dev->id.bustype = BUS_HOST;
121	input_dev->dev.parent = &pdev->dev;
122
123	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
124	input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
125	input_set_abs_params(input_dev, ABS_X, 270, 3900, 0, 0);
126	input_set_abs_params(input_dev, ABS_Y, 180, 3700, 0, 0);
127
128	error = devm_request_irq(&pdev->dev, IRQ_GPIO9,
129				 jornada720_ts_interrupt,
130				 IRQF_TRIGGER_RISING,
131				 "HP7XX Touchscreen driver", pdev);
132	if (error) {
133		dev_err(&pdev->dev, "HP7XX TS : Unable to acquire irq!\n");
134		return error;
135	}
136
137	error = input_register_device(jornada_ts->dev);
138	if (error)
139		return error;
140
141	return 0;
142}
143
144/* work with hotplug and coldplug */
145MODULE_ALIAS("platform:jornada_ts");
146
147static struct platform_driver jornada720_ts_driver = {
148	.probe		= jornada720_ts_probe,
149	.driver		= {
150		.name	= "jornada_ts",
151	},
152};
153module_platform_driver(jornada720_ts_driver);
154