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11#include <linux/module.h>
12#include <linux/platform_device.h>
13#include <linux/input-polldev.h>
14#include <linux/gpio.h>
15#include <linux/gpio_mouse.h>
16
17
18
19
20
21
22static void gpio_mouse_scan(struct input_polled_dev *dev)
23{
24 struct gpio_mouse_platform_data *gpio = dev->private;
25 struct input_dev *input = dev->input;
26 int x, y;
27
28 if (gpio->bleft >= 0)
29 input_report_key(input, BTN_LEFT,
30 gpio_get_value(gpio->bleft) ^ gpio->polarity);
31 if (gpio->bmiddle >= 0)
32 input_report_key(input, BTN_MIDDLE,
33 gpio_get_value(gpio->bmiddle) ^ gpio->polarity);
34 if (gpio->bright >= 0)
35 input_report_key(input, BTN_RIGHT,
36 gpio_get_value(gpio->bright) ^ gpio->polarity);
37
38 x = (gpio_get_value(gpio->right) ^ gpio->polarity)
39 - (gpio_get_value(gpio->left) ^ gpio->polarity);
40 y = (gpio_get_value(gpio->down) ^ gpio->polarity)
41 - (gpio_get_value(gpio->up) ^ gpio->polarity);
42
43 input_report_rel(input, REL_X, x);
44 input_report_rel(input, REL_Y, y);
45 input_sync(input);
46}
47
48static int gpio_mouse_probe(struct platform_device *pdev)
49{
50 struct gpio_mouse_platform_data *pdata = dev_get_platdata(&pdev->dev);
51 struct input_polled_dev *input_poll;
52 struct input_dev *input;
53 int pin, i;
54 int error;
55
56 if (!pdata) {
57 dev_err(&pdev->dev, "no platform data\n");
58 error = -ENXIO;
59 goto out;
60 }
61
62 if (pdata->scan_ms < 0) {
63 dev_err(&pdev->dev, "invalid scan time\n");
64 error = -EINVAL;
65 goto out;
66 }
67
68 for (i = 0; i < GPIO_MOUSE_PIN_MAX; i++) {
69 pin = pdata->pins[i];
70
71 if (pin < 0) {
72
73 if (i <= GPIO_MOUSE_PIN_RIGHT) {
74
75 dev_err(&pdev->dev,
76 "missing GPIO for directions\n");
77 error = -EINVAL;
78 goto out_free_gpios;
79 }
80
81 if (i == GPIO_MOUSE_PIN_BLEFT)
82 dev_dbg(&pdev->dev, "no left button defined\n");
83
84 } else {
85 error = gpio_request(pin, "gpio_mouse");
86 if (error) {
87 dev_err(&pdev->dev, "fail %d pin (%d idx)\n",
88 pin, i);
89 goto out_free_gpios;
90 }
91
92 gpio_direction_input(pin);
93 }
94 }
95
96 input_poll = input_allocate_polled_device();
97 if (!input_poll) {
98 dev_err(&pdev->dev, "not enough memory for input device\n");
99 error = -ENOMEM;
100 goto out_free_gpios;
101 }
102
103 platform_set_drvdata(pdev, input_poll);
104
105
106 input_poll->private = pdata;
107 input_poll->poll = gpio_mouse_scan;
108 input_poll->poll_interval = pdata->scan_ms;
109
110 input = input_poll->input;
111 input->name = pdev->name;
112 input->id.bustype = BUS_HOST;
113 input->dev.parent = &pdev->dev;
114
115 input_set_capability(input, EV_REL, REL_X);
116 input_set_capability(input, EV_REL, REL_Y);
117 if (pdata->bleft >= 0)
118 input_set_capability(input, EV_KEY, BTN_LEFT);
119 if (pdata->bmiddle >= 0)
120 input_set_capability(input, EV_KEY, BTN_MIDDLE);
121 if (pdata->bright >= 0)
122 input_set_capability(input, EV_KEY, BTN_RIGHT);
123
124 error = input_register_polled_device(input_poll);
125 if (error) {
126 dev_err(&pdev->dev, "could not register input device\n");
127 goto out_free_polldev;
128 }
129
130 dev_dbg(&pdev->dev, "%d ms scan time, buttons: %s%s%s\n",
131 pdata->scan_ms,
132 pdata->bleft < 0 ? "" : "left ",
133 pdata->bmiddle < 0 ? "" : "middle ",
134 pdata->bright < 0 ? "" : "right");
135
136 return 0;
137
138 out_free_polldev:
139 input_free_polled_device(input_poll);
140
141 out_free_gpios:
142 while (--i >= 0) {
143 pin = pdata->pins[i];
144 if (pin)
145 gpio_free(pin);
146 }
147 out:
148 return error;
149}
150
151static int gpio_mouse_remove(struct platform_device *pdev)
152{
153 struct input_polled_dev *input = platform_get_drvdata(pdev);
154 struct gpio_mouse_platform_data *pdata = input->private;
155 int pin, i;
156
157 input_unregister_polled_device(input);
158 input_free_polled_device(input);
159
160 for (i = 0; i < GPIO_MOUSE_PIN_MAX; i++) {
161 pin = pdata->pins[i];
162 if (pin >= 0)
163 gpio_free(pin);
164 }
165
166 return 0;
167}
168
169static struct platform_driver gpio_mouse_device_driver = {
170 .probe = gpio_mouse_probe,
171 .remove = gpio_mouse_remove,
172 .driver = {
173 .name = "gpio_mouse",
174 }
175};
176module_platform_driver(gpio_mouse_device_driver);
177
178MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
179MODULE_DESCRIPTION("GPIO mouse driver");
180MODULE_LICENSE("GPL");
181MODULE_ALIAS("platform:gpio_mouse");
182
183
