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 
23 #include <mach/hardware.h>
24 #include <mach/jornada720.h>
25 
26 MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson@gmail.com>");
27 MODULE_DESCRIPTION("HP Jornada 710/720/728 touchscreen driver");
28 MODULE_LICENSE("GPL v2");
29 
30 struct jornada_ts {
31 	struct input_dev *dev;
32 	int x_data[4];		/* X sample values */
33 	int y_data[4];		/* Y sample values */
34 };
35 
36 static void jornada720_ts_collect_data(struct jornada_ts *jornada_ts)
37 {
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 
56 static 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 
67 static 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 
100 static int __devinit 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 = kzalloc(sizeof(struct jornada_ts), GFP_KERNEL);
107 	input_dev = input_allocate_device();
108 
109 	if (!jornada_ts || !input_dev) {
110 		error = -ENOMEM;
111 		goto fail1;
112 	}
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 = request_irq(IRQ_GPIO9,
129 			jornada720_ts_interrupt,
130 			IRQF_DISABLED | IRQF_TRIGGER_RISING,
131 			"HP7XX Touchscreen driver", pdev);
132 	if (error) {
133 		printk(KERN_INFO "HP7XX TS : Unable to acquire irq!\n");
134 		goto fail1;
135 	}
136 
137 	error = input_register_device(jornada_ts->dev);
138 	if (error)
139 		goto fail2;
140 
141 	return 0;
142 
143  fail2:
144 	free_irq(IRQ_GPIO9, pdev);
145  fail1:
146 	platform_set_drvdata(pdev, NULL);
147 	input_free_device(input_dev);
148 	kfree(jornada_ts);
149 	return error;
150 }
151 
152 static int __devexit jornada720_ts_remove(struct platform_device *pdev)
153 {
154 	struct jornada_ts *jornada_ts = platform_get_drvdata(pdev);
155 
156 	free_irq(IRQ_GPIO9, pdev);
157 	platform_set_drvdata(pdev, NULL);
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		= __devexit_p(jornada720_ts_remove),
170 	.driver		= {
171 		.name	= "jornada_ts",
172 		.owner	= THIS_MODULE,
173 	},
174 };
175 
176 static int __init jornada720_ts_init(void)
177 {
178 	return platform_driver_register(&jornada720_ts_driver);
179 }
180 
181 static void __exit jornada720_ts_exit(void)
182 {
183 	platform_driver_unregister(&jornada720_ts_driver);
184 }
185 
186 module_init(jornada720_ts_init);
187 module_exit(jornada720_ts_exit);
188