xref: /linux/drivers/input/touchscreen/jornada720_ts.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 
27 MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson@gmail.com>");
28 MODULE_DESCRIPTION("HP Jornada 710/720/728 touchscreen driver");
29 MODULE_LICENSE("GPL v2");
30 
31 struct 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 
37 static 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 
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 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 */
145 MODULE_ALIAS("platform:jornada_ts");
146 
147 static struct platform_driver jornada720_ts_driver = {
148 	.probe		= jornada720_ts_probe,
149 	.driver		= {
150 		.name	= "jornada_ts",
151 	},
152 };
153 module_platform_driver(jornada720_ts_driver);
154