1 /*
2 * Driver for simulating a mouse on GPIO lines.
3 *
4 * Copyright (C) 2007 Atmel Corporation
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11 #include <linux/init.h>
12 #include <linux/version.h>
13 #include <linux/module.h>
14 #include <linux/platform_device.h>
15 #include <linux/input-polldev.h>
16 #include <linux/gpio_mouse.h>
17
18 #include <asm/gpio.h>
19
20 /*
21 * Timer function which is run every scan_ms ms when the device is opened.
22 * The dev input varaible is set to the the input_dev pointer.
23 */
24 static void gpio_mouse_scan(struct input_polled_dev *dev)
25 {
26 struct gpio_mouse_platform_data *gpio = dev->private;
27 struct input_dev *input = dev->input;
28 int x, y;
29
30 if (gpio->bleft >= 0)
31 input_report_key(input, BTN_LEFT,
32 gpio_get_value(gpio->bleft) ^ gpio->polarity);
33 if (gpio->bmiddle >= 0)
34 input_report_key(input, BTN_MIDDLE,
35 gpio_get_value(gpio->bmiddle) ^ gpio->polarity);
36 if (gpio->bright >= 0)
37 input_report_key(input, BTN_RIGHT,
38 gpio_get_value(gpio->bright) ^ gpio->polarity);
39
40 x = (gpio_get_value(gpio->right) ^ gpio->polarity)
41 - (gpio_get_value(gpio->left) ^ gpio->polarity);
42 y = (gpio_get_value(gpio->down) ^ gpio->polarity)
43 - (gpio_get_value(gpio->up) ^ gpio->polarity);
44
45 input_report_rel(input, REL_X, x);
46 input_report_rel(input, REL_Y, y);
47 input_sync(input);
48 }
49
50 static int __init gpio_mouse_probe(struct platform_device *pdev)
51 {
52 struct gpio_mouse_platform_data *pdata = pdev->dev.platform_data;
53 struct input_polled_dev *input_poll;
54 struct input_dev *input;
55 int pin, i;
56 int error;
57
58 if (!pdata) {
59 dev_err(&pdev->dev, "no platform data\n");
60 error = -ENXIO;
61 goto out;
62 }
63
64 if (pdata->scan_ms < 0) {
65 dev_err(&pdev->dev, "invalid scan time\n");
66 error = -EINVAL;
67 goto out;
68 }
69
70 for (i = 0; i < GPIO_MOUSE_PIN_MAX; i++) {
71 pin = pdata->pins[i];
72
73 if (pin < 0) {
74
75 if (i <= GPIO_MOUSE_PIN_RIGHT) {
76 /* Mouse direction is required. */
77 dev_err(&pdev->dev,
78 "missing GPIO for directions\n");
79 error = -EINVAL;
80 goto out_free_gpios;
81 }
82
83 if (i == GPIO_MOUSE_PIN_BLEFT)
84 dev_dbg(&pdev->dev, "no left button defined\n");
85
86 } else {
87 error = gpio_request(pin, "gpio_mouse");
88 if (error) {
89 dev_err(&pdev->dev, "fail %d pin (%d idx)\n",
90 pin, i);
91 goto out_free_gpios;
92 }
93
94 gpio_direction_input(pin);
95 }
96 }
97
98 input_poll = input_allocate_polled_device();
99 if (!input_poll) {
100 dev_err(&pdev->dev, "not enough memory for input device\n");
101 error = -ENOMEM;
102 goto out_free_gpios;
103 }
104
105 platform_set_drvdata(pdev, input_poll);
106
107 /* set input-polldev handlers */
108 input_poll->private = pdata;
109 input_poll->poll = gpio_mouse_scan;
110 input_poll->poll_interval = pdata->scan_ms;
111
112 input = input_poll->input;
113 input->name = pdev->name;
114 input->id.bustype = BUS_HOST;
115 input->dev.parent = &pdev->dev;
116
117 input_set_capability(input, EV_REL, REL_X);
118 input_set_capability(input, EV_REL, REL_Y);
119 if (pdata->bleft >= 0)
120 input_set_capability(input, EV_KEY, BTN_LEFT);
121 if (pdata->bmiddle >= 0)
122 input_set_capability(input, EV_KEY, BTN_MIDDLE);
123 if (pdata->bright >= 0)
124 input_set_capability(input, EV_KEY, BTN_RIGHT);
125
126 error = input_register_polled_device(input_poll);
127 if (error) {
128 dev_err(&pdev->dev, "could not register input device\n");
129 goto out_free_polldev;
130 }
131
132 dev_dbg(&pdev->dev, "%d ms scan time, buttons: %s%s%s\n",
133 pdata->scan_ms,
134 pdata->bleft < 0 ? "" : "left ",
135 pdata->bmiddle < 0 ? "" : "middle ",
136 pdata->bright < 0 ? "" : "right");
137
138 return 0;
139
140 out_free_polldev:
141 input_free_polled_device(input_poll);
142 platform_set_drvdata(pdev, NULL);
143
144 out_free_gpios:
145 while (--i >= 0) {
146 pin = pdata->pins[i];
147 if (pin)
148 gpio_free(pin);
149 }
150 out:
151 return error;
152 }
153
154 static int __devexit gpio_mouse_remove(struct platform_device *pdev)
155 {
156 struct input_polled_dev *input = platform_get_drvdata(pdev);
157 struct gpio_mouse_platform_data *pdata = input->private;
158 int pin, i;
159
160 input_unregister_polled_device(input);
161 input_free_polled_device(input);
162
163 for (i = 0; i < GPIO_MOUSE_PIN_MAX; i++) {
164 pin = pdata->pins[i];
165 if (pin >= 0)
166 gpio_free(pin);
167 }
168
169 platform_set_drvdata(pdev, NULL);
170
171 return 0;
172 }
173
174 struct platform_driver gpio_mouse_device_driver = {
175 .remove = __devexit_p(gpio_mouse_remove),
176 .driver = {
177 .name = "gpio_mouse",
178 }
179 };
180
181 static int __init gpio_mouse_init(void)
182 {
183 return platform_driver_probe(&gpio_mouse_device_driver,
184 gpio_mouse_probe);
185 }
186 module_init(gpio_mouse_init);
187
188 static void __exit gpio_mouse_exit(void)
189 {
190 platform_driver_unregister(&gpio_mouse_device_driver);
191 }
192 module_exit(gpio_mouse_exit);
193
194 MODULE_AUTHOR("Hans-Christian Egtvedt <hcegtvedt@atmel.com>");
195 MODULE_DESCRIPTION("GPIO mouse driver");
196 MODULE_LICENSE("GPL");
197
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