xref: /linux/drivers/macintosh/mac_hid.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 /*
2  * drivers/macintosh/mac_hid.c
3  *
4  * HID support stuff for Macintosh computers.
5  *
6  * Copyright (C) 2000 Franz Sirl.
7  *
8  * This file will soon be removed in favor of an uinput userspace tool.
9  */
10 
11 #include <linux/init.h>
12 #include <linux/proc_fs.h>
13 #include <linux/sysctl.h>
14 #include <linux/input.h>
15 #include <linux/module.h>
16 #include <linux/slab.h>
17 
18 MODULE_LICENSE("GPL");
19 
20 static int mouse_emulate_buttons;
21 static int mouse_button2_keycode = KEY_RIGHTCTRL;	/* right control key */
22 static int mouse_button3_keycode = KEY_RIGHTALT;	/* right option key */
23 
24 static struct input_dev *mac_hid_emumouse_dev;
25 
26 static DEFINE_MUTEX(mac_hid_emumouse_mutex);
27 
28 static int mac_hid_create_emumouse(void)
29 {
30 	static struct lock_class_key mac_hid_emumouse_dev_event_class;
31 	static struct lock_class_key mac_hid_emumouse_dev_mutex_class;
32 	int err;
33 
34 	mac_hid_emumouse_dev = input_allocate_device();
35 	if (!mac_hid_emumouse_dev)
36 		return -ENOMEM;
37 
38 	lockdep_set_class(&mac_hid_emumouse_dev->event_lock,
39 			  &mac_hid_emumouse_dev_event_class);
40 	lockdep_set_class(&mac_hid_emumouse_dev->mutex,
41 			  &mac_hid_emumouse_dev_mutex_class);
42 
43 	mac_hid_emumouse_dev->name = "Macintosh mouse button emulation";
44 	mac_hid_emumouse_dev->id.bustype = BUS_ADB;
45 	mac_hid_emumouse_dev->id.vendor = 0x0001;
46 	mac_hid_emumouse_dev->id.product = 0x0001;
47 	mac_hid_emumouse_dev->id.version = 0x0100;
48 
49 	mac_hid_emumouse_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL);
50 	mac_hid_emumouse_dev->keybit[BIT_WORD(BTN_MOUSE)] =
51 		BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_MIDDLE) | BIT_MASK(BTN_RIGHT);
52 	mac_hid_emumouse_dev->relbit[0] = BIT_MASK(REL_X) | BIT_MASK(REL_Y);
53 
54 	err = input_register_device(mac_hid_emumouse_dev);
55 	if (err) {
56 		input_free_device(mac_hid_emumouse_dev);
57 		mac_hid_emumouse_dev = NULL;
58 		return err;
59 	}
60 
61 	return 0;
62 }
63 
64 static void mac_hid_destroy_emumouse(void)
65 {
66 	input_unregister_device(mac_hid_emumouse_dev);
67 	mac_hid_emumouse_dev = NULL;
68 }
69 
70 static bool mac_hid_emumouse_filter(struct input_handle *handle,
71 				    unsigned int type, unsigned int code,
72 				    int value)
73 {
74 	unsigned int btn;
75 
76 	if (type != EV_KEY)
77 		return false;
78 
79 	if (code == mouse_button2_keycode)
80 		btn = BTN_MIDDLE;
81 	else if (code == mouse_button3_keycode)
82 		btn = BTN_RIGHT;
83 	else
84 		return false;
85 
86 	input_report_key(mac_hid_emumouse_dev, btn, value);
87 	input_sync(mac_hid_emumouse_dev);
88 
89 	return true;
90 }
91 
92 static int mac_hid_emumouse_connect(struct input_handler *handler,
93 				    struct input_dev *dev,
94 				    const struct input_device_id *id)
95 {
96 	struct input_handle *handle;
97 	int error;
98 
99 	/* Don't bind to ourselves */
100 	if (dev == mac_hid_emumouse_dev)
101 		return -ENODEV;
102 
103 	handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL);
104 	if (!handle)
105 		return -ENOMEM;
106 
107 	handle->dev = dev;
108 	handle->handler = handler;
109 	handle->name = "mac-button-emul";
110 
111 	error = input_register_handle(handle);
112 	if (error) {
113 		printk(KERN_ERR
114 			"mac_hid: Failed to register button emulation handle, "
115 			"error %d\n", error);
116 		goto err_free;
117 	}
118 
119 	error = input_open_device(handle);
120 	if (error) {
121 		printk(KERN_ERR
122 			"mac_hid: Failed to open input device, error %d\n",
123 			error);
124 		goto err_unregister;
125 	}
126 
127 	return 0;
128 
129  err_unregister:
130 	input_unregister_handle(handle);
131  err_free:
132 	kfree(handle);
133 	return error;
134 }
135 
136 static void mac_hid_emumouse_disconnect(struct input_handle *handle)
137 {
138 	input_close_device(handle);
139 	input_unregister_handle(handle);
140 	kfree(handle);
141 }
142 
143 static const struct input_device_id mac_hid_emumouse_ids[] = {
144 	{
145 		.flags = INPUT_DEVICE_ID_MATCH_EVBIT,
146 		.evbit = { BIT_MASK(EV_KEY) },
147 	},
148 	{ },
149 };
150 
151 MODULE_DEVICE_TABLE(input, mac_hid_emumouse_ids);
152 
153 static struct input_handler mac_hid_emumouse_handler = {
154 	.filter		= mac_hid_emumouse_filter,
155 	.connect	= mac_hid_emumouse_connect,
156 	.disconnect	= mac_hid_emumouse_disconnect,
157 	.name		= "mac-button-emul",
158 	.id_table	= mac_hid_emumouse_ids,
159 };
160 
161 static int mac_hid_start_emulation(void)
162 {
163 	int err;
164 
165 	err = mac_hid_create_emumouse();
166 	if (err)
167 		return err;
168 
169 	err = input_register_handler(&mac_hid_emumouse_handler);
170 	if (err) {
171 		mac_hid_destroy_emumouse();
172 		return err;
173 	}
174 
175 	return 0;
176 }
177 
178 static void mac_hid_stop_emulation(void)
179 {
180 	input_unregister_handler(&mac_hid_emumouse_handler);
181 	mac_hid_destroy_emumouse();
182 }
183 
184 static int mac_hid_toggle_emumouse(ctl_table *table, int write,
185 				   void __user *buffer, size_t *lenp,
186 				   loff_t *ppos)
187 {
188 	int *valp = table->data;
189 	int old_val = *valp;
190 	int rc;
191 
192 	rc = mutex_lock_killable(&mac_hid_emumouse_mutex);
193 	if (rc)
194 		return rc;
195 
196 	rc = proc_dointvec(table, write, buffer, lenp, ppos);
197 
198 	if (rc == 0 && write && *valp != old_val) {
199 		if (*valp == 1)
200 			rc = mac_hid_start_emulation();
201 		else if (*valp == 0)
202 			mac_hid_stop_emulation();
203 		else
204 			rc = -EINVAL;
205 	}
206 
207 	/* Restore the old value in case of error */
208 	if (rc)
209 		*valp = old_val;
210 
211 	mutex_unlock(&mac_hid_emumouse_mutex);
212 
213 	return rc;
214 }
215 
216 /* file(s) in /proc/sys/dev/mac_hid */
217 static ctl_table mac_hid_files[] = {
218 	{
219 		.procname	= "mouse_button_emulation",
220 		.data		= &mouse_emulate_buttons,
221 		.maxlen		= sizeof(int),
222 		.mode		= 0644,
223 		.proc_handler	= mac_hid_toggle_emumouse,
224 	},
225 	{
226 		.procname	= "mouse_button2_keycode",
227 		.data		= &mouse_button2_keycode,
228 		.maxlen		= sizeof(int),
229 		.mode		= 0644,
230 		.proc_handler	= proc_dointvec,
231 	},
232 	{
233 		.procname	= "mouse_button3_keycode",
234 		.data		= &mouse_button3_keycode,
235 		.maxlen		= sizeof(int),
236 		.mode		= 0644,
237 		.proc_handler	= proc_dointvec,
238 	},
239 	{ }
240 };
241 
242 /* dir in /proc/sys/dev */
243 static ctl_table mac_hid_dir[] = {
244 	{
245 		.procname	= "mac_hid",
246 		.maxlen		= 0,
247 		.mode		= 0555,
248 		.child		= mac_hid_files,
249 	},
250 	{ }
251 };
252 
253 /* /proc/sys/dev itself, in case that is not there yet */
254 static ctl_table mac_hid_root_dir[] = {
255 	{
256 		.procname	= "dev",
257 		.maxlen		= 0,
258 		.mode		= 0555,
259 		.child		= mac_hid_dir,
260 	},
261 	{ }
262 };
263 
264 static struct ctl_table_header *mac_hid_sysctl_header;
265 
266 static int __init mac_hid_init(void)
267 {
268 	mac_hid_sysctl_header = register_sysctl_table(mac_hid_root_dir);
269 	if (!mac_hid_sysctl_header)
270 		return -ENOMEM;
271 
272 	return 0;
273 }
274 module_init(mac_hid_init);
275 
276 static void __exit mac_hid_exit(void)
277 {
278 	unregister_sysctl_table(mac_hid_sysctl_header);
279 
280 	if (mouse_emulate_buttons)
281 		mac_hid_stop_emulation();
282 }
283 module_exit(mac_hid_exit);
284