xref: /linux/drivers/input/touchscreen/jornada720_ts.c (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
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 #include <linux/slab.h>
22 #include <linux/io.h>
23 
24 #include <mach/hardware.h>
25 #include <mach/jornada720.h>
26 #include <mach/irqs.h>
27 
28 MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson@gmail.com>");
29 MODULE_DESCRIPTION("HP Jornada 710/720/728 touchscreen driver");
30 MODULE_LICENSE("GPL v2");
31 
32 struct jornada_ts {
33 	struct input_dev *dev;
34 	int x_data[4];		/* X sample values */
35 	int y_data[4];		/* Y sample values */
36 };
37 
38 static void jornada720_ts_collect_data(struct jornada_ts *jornada_ts)
39 {
40 
41     /* 3 low word X samples */
42     jornada_ts->x_data[0] = jornada_ssp_byte(TXDUMMY);
43     jornada_ts->x_data[1] = jornada_ssp_byte(TXDUMMY);
44     jornada_ts->x_data[2] = jornada_ssp_byte(TXDUMMY);
45 
46     /* 3 low word Y samples */
47     jornada_ts->y_data[0] = jornada_ssp_byte(TXDUMMY);
48     jornada_ts->y_data[1] = jornada_ssp_byte(TXDUMMY);
49     jornada_ts->y_data[2] = jornada_ssp_byte(TXDUMMY);
50 
51     /* combined x samples bits */
52     jornada_ts->x_data[3] = jornada_ssp_byte(TXDUMMY);
53 
54     /* combined y samples bits */
55     jornada_ts->y_data[3] = jornada_ssp_byte(TXDUMMY);
56 }
57 
58 static int jornada720_ts_average(int coords[4])
59 {
60 	int coord, high_bits = coords[3];
61 
62 	coord  = coords[0] | ((high_bits & 0x03) << 8);
63 	coord += coords[1] | ((high_bits & 0x0c) << 6);
64 	coord += coords[2] | ((high_bits & 0x30) << 4);
65 
66 	return coord / 3;
67 }
68 
69 static irqreturn_t jornada720_ts_interrupt(int irq, void *dev_id)
70 {
71 	struct platform_device *pdev = dev_id;
72 	struct jornada_ts *jornada_ts = platform_get_drvdata(pdev);
73 	struct input_dev *input = jornada_ts->dev;
74 	int x, y;
75 
76 	/* If GPIO_GPIO9 is set to high then report pen up */
77 	if (GPLR & GPIO_GPIO(9)) {
78 		input_report_key(input, BTN_TOUCH, 0);
79 		input_sync(input);
80 	} else {
81 		jornada_ssp_start();
82 
83 		/* proper reply to request is always TXDUMMY */
84 		if (jornada_ssp_inout(GETTOUCHSAMPLES) == TXDUMMY) {
85 			jornada720_ts_collect_data(jornada_ts);
86 
87 			x = jornada720_ts_average(jornada_ts->x_data);
88 			y = jornada720_ts_average(jornada_ts->y_data);
89 
90 			input_report_key(input, BTN_TOUCH, 1);
91 			input_report_abs(input, ABS_X, x);
92 			input_report_abs(input, ABS_Y, y);
93 			input_sync(input);
94 		}
95 
96 		jornada_ssp_end();
97 	}
98 
99 	return IRQ_HANDLED;
100 }
101 
102 static int jornada720_ts_probe(struct platform_device *pdev)
103 {
104 	struct jornada_ts *jornada_ts;
105 	struct input_dev *input_dev;
106 	int error;
107 
108 	jornada_ts = kzalloc(sizeof(struct jornada_ts), GFP_KERNEL);
109 	input_dev = input_allocate_device();
110 
111 	if (!jornada_ts || !input_dev) {
112 		error = -ENOMEM;
113 		goto fail1;
114 	}
115 
116 	platform_set_drvdata(pdev, jornada_ts);
117 
118 	jornada_ts->dev = input_dev;
119 
120 	input_dev->name = "HP Jornada 7xx Touchscreen";
121 	input_dev->phys = "jornadats/input0";
122 	input_dev->id.bustype = BUS_HOST;
123 	input_dev->dev.parent = &pdev->dev;
124 
125 	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
126 	input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
127 	input_set_abs_params(input_dev, ABS_X, 270, 3900, 0, 0);
128 	input_set_abs_params(input_dev, ABS_Y, 180, 3700, 0, 0);
129 
130 	error = request_irq(IRQ_GPIO9,
131 			jornada720_ts_interrupt,
132 			IRQF_TRIGGER_RISING,
133 			"HP7XX Touchscreen driver", pdev);
134 	if (error) {
135 		printk(KERN_INFO "HP7XX TS : Unable to acquire irq!\n");
136 		goto fail1;
137 	}
138 
139 	error = input_register_device(jornada_ts->dev);
140 	if (error)
141 		goto fail2;
142 
143 	return 0;
144 
145  fail2:
146 	free_irq(IRQ_GPIO9, pdev);
147  fail1:
148 	input_free_device(input_dev);
149 	kfree(jornada_ts);
150 	return error;
151 }
152 
153 static int jornada720_ts_remove(struct platform_device *pdev)
154 {
155 	struct jornada_ts *jornada_ts = platform_get_drvdata(pdev);
156 
157 	free_irq(IRQ_GPIO9, pdev);
158 	input_unregister_device(jornada_ts->dev);
159 	kfree(jornada_ts);
160 
161 	return 0;
162 }
163 
164 /* work with hotplug and coldplug */
165 MODULE_ALIAS("platform:jornada_ts");
166 
167 static struct platform_driver jornada720_ts_driver = {
168 	.probe		= jornada720_ts_probe,
169 	.remove		= jornada720_ts_remove,
170 	.driver		= {
171 		.name	= "jornada_ts",
172 		.owner	= THIS_MODULE,
173 	},
174 };
175 module_platform_driver(jornada720_ts_driver);
176