1 /*
2 * Apple Motion Sensor driver (joystick emulation)
3 *
4 * Copyright (C) 2005 Stelian Pop (stelian@popies.net)
5 * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 */
12
13 #include <linux/module.h>
14
15 #include <linux/types.h>
16 #include <linux/errno.h>
17 #include <linux/init.h>
18 #include <linux/delay.h>
19
20 #include "ams.h"
21
22 static bool joystick;
23 module_param(joystick, bool, S_IRUGO);
24 MODULE_PARM_DESC(joystick, "Enable the input class device on module load");
25
26 static bool invert;
27 module_param(invert, bool, S_IWUSR | S_IRUGO);
28 MODULE_PARM_DESC(invert, "Invert input data on X and Y axis");
29
30 static DEFINE_MUTEX(ams_input_mutex);
31
ams_idev_poll(struct input_polled_dev * dev)32 static void ams_idev_poll(struct input_polled_dev *dev)
33 {
34 struct input_dev *idev = dev->input;
35 s8 x, y, z;
36
37 mutex_lock(&ams_info.lock);
38
39 ams_sensors(&x, &y, &z);
40
41 x -= ams_info.xcalib;
42 y -= ams_info.ycalib;
43 z -= ams_info.zcalib;
44
45 input_report_abs(idev, ABS_X, invert ? -x : x);
46 input_report_abs(idev, ABS_Y, invert ? -y : y);
47 input_report_abs(idev, ABS_Z, z);
48
49 input_sync(idev);
50
51 mutex_unlock(&ams_info.lock);
52 }
53
54 /* Call with ams_info.lock held! */
ams_input_enable(void)55 static int ams_input_enable(void)
56 {
57 struct input_dev *input;
58 s8 x, y, z;
59 int error;
60
61 ams_sensors(&x, &y, &z);
62 ams_info.xcalib = x;
63 ams_info.ycalib = y;
64 ams_info.zcalib = z;
65
66 ams_info.idev = input_allocate_polled_device();
67 if (!ams_info.idev)
68 return -ENOMEM;
69
70 ams_info.idev->poll = ams_idev_poll;
71 ams_info.idev->poll_interval = 25;
72
73 input = ams_info.idev->input;
74 input->name = "Apple Motion Sensor";
75 input->id.bustype = ams_info.bustype;
76 input->id.vendor = 0;
77 input->dev.parent = &ams_info.of_dev->dev;
78
79 input_set_abs_params(input, ABS_X, -50, 50, 3, 0);
80 input_set_abs_params(input, ABS_Y, -50, 50, 3, 0);
81 input_set_abs_params(input, ABS_Z, -50, 50, 3, 0);
82
83 set_bit(EV_ABS, input->evbit);
84 set_bit(EV_KEY, input->evbit);
85 set_bit(BTN_TOUCH, input->keybit);
86
87 error = input_register_polled_device(ams_info.idev);
88 if (error) {
89 input_free_polled_device(ams_info.idev);
90 ams_info.idev = NULL;
91 return error;
92 }
93
94 joystick = 1;
95
96 return 0;
97 }
98
ams_input_disable(void)99 static void ams_input_disable(void)
100 {
101 if (ams_info.idev) {
102 input_unregister_polled_device(ams_info.idev);
103 input_free_polled_device(ams_info.idev);
104 ams_info.idev = NULL;
105 }
106
107 joystick = 0;
108 }
109
ams_input_show_joystick(struct device * dev,struct device_attribute * attr,char * buf)110 static ssize_t ams_input_show_joystick(struct device *dev,
111 struct device_attribute *attr, char *buf)
112 {
113 return sprintf(buf, "%d\n", joystick);
114 }
115
ams_input_store_joystick(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)116 static ssize_t ams_input_store_joystick(struct device *dev,
117 struct device_attribute *attr, const char *buf, size_t count)
118 {
119 unsigned long enable;
120 int error = 0;
121
122 if (strict_strtoul(buf, 0, &enable) || enable > 1)
123 return -EINVAL;
124
125 mutex_lock(&ams_input_mutex);
126
127 if (enable != joystick) {
128 if (enable)
129 error = ams_input_enable();
130 else
131 ams_input_disable();
132 }
133
134 mutex_unlock(&ams_input_mutex);
135
136 return error ? error : count;
137 }
138
139 static DEVICE_ATTR(joystick, S_IRUGO | S_IWUSR,
140 ams_input_show_joystick, ams_input_store_joystick);
141
ams_input_init(void)142 int ams_input_init(void)
143 {
144 if (joystick)
145 ams_input_enable();
146
147 return device_create_file(&ams_info.of_dev->dev, &dev_attr_joystick);
148 }
149
ams_input_exit(void)150 void ams_input_exit(void)
151 {
152 device_remove_file(&ams_info.of_dev->dev, &dev_attr_joystick);
153
154 mutex_lock(&ams_input_mutex);
155 ams_input_disable();
156 mutex_unlock(&ams_input_mutex);
157 }
158