jornada720_ts.c revision d7b5247bbcfba2bc96d4b3dec9086a4f1a31363b 
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/init.h>
18#include <linux/input.h>
19#include <linux/interrupt.h>
20#include <linux/module.h>
21
22#include <asm/hardware.h>
23#include <asm/arch/jornada720.h>
24
25MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson@gmail.com>");
26MODULE_DESCRIPTION("HP Jornada 710/720/728 touchscreen driver");
27MODULE_LICENSE("GPLv2");
28
29struct jornada_ts {
30	struct input_dev *dev;
31	int x_data[4];		/* X sample values */
32	int y_data[4];		/* Y sample values */
33};
34
35static void jornada720_ts_collect_data(struct jornada_ts *jornada_ts)
36{
37
38    /* 3 low word X samples */
39    jornada_ts->x_data[0] = jornada_ssp_byte(TXDUMMY);
40    jornada_ts->x_data[1] = jornada_ssp_byte(TXDUMMY);
41    jornada_ts->x_data[2] = jornada_ssp_byte(TXDUMMY);
42
43    /* 3 low word Y samples */
44    jornada_ts->y_data[0] = jornada_ssp_byte(TXDUMMY);
45    jornada_ts->y_data[1] = jornada_ssp_byte(TXDUMMY);
46    jornada_ts->y_data[2] = jornada_ssp_byte(TXDUMMY);
47
48    /* combined x samples bits */
49    jornada_ts->x_data[3] = jornada_ssp_byte(TXDUMMY);
50
51    /* combined y samples bits */
52    jornada_ts->y_data[3] = jornada_ssp_byte(TXDUMMY);
53}
54
55static int jornada720_ts_average(int coords[4])
56{
57	int coord, high_bits = coords[3];
58
59	coord  = coords[0] | ((high_bits & 0x03) << 8);
60	coord += coords[1] | ((high_bits & 0x0c) << 6);
61	coord += coords[2] | ((high_bits & 0x30) << 4);
62
63	return coord / 3;
64}
65
66static irqreturn_t jornada720_ts_interrupt(int irq, void *dev_id)
67{
68	struct platform_device *pdev = dev_id;
69	struct jornada_ts *jornada_ts = platform_get_drvdata(pdev);
70	struct input_dev *input = jornada_ts->dev;
71	int x, y;
72
73	/* If GPIO_GPIO9 is set to high then report pen up */
74	if (GPLR & GPIO_GPIO(9)) {
75		input_report_key(input, BTN_TOUCH, 0);
76		input_sync(input);
77	} else {
78		jornada_ssp_start();
79
80		/* proper reply to request is always TXDUMMY */
81		if (jornada_ssp_inout(GETTOUCHSAMPLES) == TXDUMMY) {
82			jornada720_ts_collect_data(jornada_ts);
83
84			x = jornada720_ts_average(jornada_ts->x_data);
85			y = jornada720_ts_average(jornada_ts->y_data);
86
87			input_report_key(input, BTN_TOUCH, 1);
88			input_report_abs(input, ABS_X, x);
89			input_report_abs(input, ABS_Y, y);
90			input_sync(input);
91		}
92
93		jornada_ssp_end();
94	}
95
96	return IRQ_HANDLED;
97}
98
99static int __devinit jornada720_ts_probe(struct platform_device *pdev)
100{
101	struct jornada_ts *jornada_ts;
102	struct input_dev *input_dev;
103	int error;
104
105	jornada_ts = kzalloc(sizeof(struct jornada_ts), GFP_KERNEL);
106	input_dev = input_allocate_device();
107
108	if (!jornada_ts || !input_dev) {
109		error = -ENOMEM;
110		goto fail1;
111	}
112
113	platform_set_drvdata(pdev, jornada_ts);
114
115	jornada_ts->dev = input_dev;
116
117	input_dev->name = "HP Jornada 7xx Touchscreen";
118	input_dev->phys = "jornadats/input0";
119	input_dev->id.bustype = BUS_HOST;
120	input_dev->dev.parent = &pdev->dev;
121
122	input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
123	input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
124	input_set_abs_params(input_dev, ABS_X, 270, 3900, 0, 0);
125	input_set_abs_params(input_dev, ABS_Y, 180, 3700, 0, 0);
126
127	error = request_irq(IRQ_GPIO9,
128			jornada720_ts_interrupt,
129			IRQF_DISABLED | IRQF_TRIGGER_RISING,
130			"HP7XX Touchscreen driver", pdev);
131	if (error) {
132		printk(KERN_INFO "HP7XX TS : Unable to acquire irq!\n");
133		goto fail1;
134	}
135
136	error = input_register_device(jornada_ts->dev);
137	if (error)
138		goto fail2;
139
140	return 0;
141
142 fail2:
143	free_irq(IRQ_GPIO9, pdev);
144 fail1:
145	platform_set_drvdata(pdev, NULL);
146	input_free_device(input_dev);
147	kfree(jornada_ts);
148	return error;
149}
150
151static int __devexit jornada720_ts_remove(struct platform_device *pdev)
152{
153	struct jornada_ts *jornada_ts = platform_get_drvdata(pdev);
154
155	free_irq(IRQ_GPIO9, pdev);
156	platform_set_drvdata(pdev, NULL);
157	input_unregister_device(jornada_ts->dev);
158	kfree(jornada_ts);
159
160	return 0;
161}
162
163/* work with hotplug and coldplug */
164MODULE_ALIAS("platform:jornada_ts");
165
166static struct platform_driver jornada720_ts_driver = {
167	.probe		= jornada720_ts_probe,
168	.remove		= __devexit_p(jornada720_ts_remove),
169	.driver		= {
170		.name	= "jornada_ts",
171		.owner	= THIS_MODULE,
172	},
173};
174
175static int __init jornada720_ts_init(void)
176{
177	return platform_driver_register(&jornada720_ts_driver);
178}
179
180static void __exit jornada720_ts_exit(void)
181{
182	platform_driver_unregister(&jornada720_ts_driver);
183}
184
185module_init(jornada720_ts_init);
186module_exit(jornada720_ts_exit);
187