1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * drivers/macintosh/mac_hid.c 4 * 5 * HID support stuff for Macintosh computers. 6 * 7 * Copyright (C) 2000 Franz Sirl. 8 * 9 * This file will soon be removed in favor of an uinput userspace tool. 10 */ 11 12 #include <linux/init.h> 13 #include <linux/proc_fs.h> 14 #include <linux/sysctl.h> 15 #include <linux/input.h> 16 #include <linux/module.h> 17 #include <linux/slab.h> 18 19 MODULE_DESCRIPTION("Mouse button 2+3 emulation"); 20 MODULE_LICENSE("GPL"); 21 22 static int mouse_emulate_buttons; 23 static int mouse_button2_keycode = KEY_RIGHTCTRL; /* right control key */ 24 static int mouse_button3_keycode = KEY_RIGHTALT; /* right option key */ 25 26 static struct input_dev *mac_hid_emumouse_dev; 27 28 static DEFINE_MUTEX(mac_hid_emumouse_mutex); 29 30 static int mac_hid_create_emumouse(void) 31 { 32 static struct lock_class_key mac_hid_emumouse_dev_event_class; 33 static struct lock_class_key mac_hid_emumouse_dev_mutex_class; 34 int err; 35 36 mac_hid_emumouse_dev = input_allocate_device(); 37 if (!mac_hid_emumouse_dev) 38 return -ENOMEM; 39 40 lockdep_set_class(&mac_hid_emumouse_dev->event_lock, 41 &mac_hid_emumouse_dev_event_class); 42 lockdep_set_class(&mac_hid_emumouse_dev->mutex, 43 &mac_hid_emumouse_dev_mutex_class); 44 45 mac_hid_emumouse_dev->name = "Macintosh mouse button emulation"; 46 mac_hid_emumouse_dev->id.bustype = BUS_ADB; 47 mac_hid_emumouse_dev->id.vendor = 0x0001; 48 mac_hid_emumouse_dev->id.product = 0x0001; 49 mac_hid_emumouse_dev->id.version = 0x0100; 50 51 mac_hid_emumouse_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL); 52 mac_hid_emumouse_dev->keybit[BIT_WORD(BTN_MOUSE)] = 53 BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_MIDDLE) | BIT_MASK(BTN_RIGHT); 54 mac_hid_emumouse_dev->relbit[0] = BIT_MASK(REL_X) | BIT_MASK(REL_Y); 55 56 err = input_register_device(mac_hid_emumouse_dev); 57 if (err) { 58 input_free_device(mac_hid_emumouse_dev); 59 mac_hid_emumouse_dev = NULL; 60 return err; 61 } 62 63 return 0; 64 } 65 66 static void mac_hid_destroy_emumouse(void) 67 { 68 input_unregister_device(mac_hid_emumouse_dev); 69 mac_hid_emumouse_dev = NULL; 70 } 71 72 static bool mac_hid_emumouse_filter(struct input_handle *handle, 73 unsigned int type, unsigned int code, 74 int value) 75 { 76 unsigned int btn; 77 78 if (type != EV_KEY) 79 return false; 80 81 if (code == mouse_button2_keycode) 82 btn = BTN_MIDDLE; 83 else if (code == mouse_button3_keycode) 84 btn = BTN_RIGHT; 85 else 86 return false; 87 88 input_report_key(mac_hid_emumouse_dev, btn, value); 89 input_sync(mac_hid_emumouse_dev); 90 91 return true; 92 } 93 94 static int mac_hid_emumouse_connect(struct input_handler *handler, 95 struct input_dev *dev, 96 const struct input_device_id *id) 97 { 98 struct input_handle *handle; 99 int error; 100 101 /* Don't bind to ourselves */ 102 if (dev == mac_hid_emumouse_dev) 103 return -ENODEV; 104 105 handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL); 106 if (!handle) 107 return -ENOMEM; 108 109 handle->dev = dev; 110 handle->handler = handler; 111 handle->name = "mac-button-emul"; 112 113 error = input_register_handle(handle); 114 if (error) { 115 printk(KERN_ERR 116 "mac_hid: Failed to register button emulation handle, " 117 "error %d\n", error); 118 goto err_free; 119 } 120 121 error = input_open_device(handle); 122 if (error) { 123 printk(KERN_ERR 124 "mac_hid: Failed to open input device, error %d\n", 125 error); 126 goto err_unregister; 127 } 128 129 return 0; 130 131 err_unregister: 132 input_unregister_handle(handle); 133 err_free: 134 kfree(handle); 135 return error; 136 } 137 138 static void mac_hid_emumouse_disconnect(struct input_handle *handle) 139 { 140 input_close_device(handle); 141 input_unregister_handle(handle); 142 kfree(handle); 143 } 144 145 static const struct input_device_id mac_hid_emumouse_ids[] = { 146 { 147 .flags = INPUT_DEVICE_ID_MATCH_EVBIT, 148 .evbit = { BIT_MASK(EV_KEY) }, 149 }, 150 { }, 151 }; 152 153 MODULE_DEVICE_TABLE(input, mac_hid_emumouse_ids); 154 155 static struct input_handler mac_hid_emumouse_handler = { 156 .filter = mac_hid_emumouse_filter, 157 .connect = mac_hid_emumouse_connect, 158 .disconnect = mac_hid_emumouse_disconnect, 159 .name = "mac-button-emul", 160 .id_table = mac_hid_emumouse_ids, 161 }; 162 163 static int mac_hid_start_emulation(void) 164 { 165 int err; 166 167 err = mac_hid_create_emumouse(); 168 if (err) 169 return err; 170 171 err = input_register_handler(&mac_hid_emumouse_handler); 172 if (err) { 173 mac_hid_destroy_emumouse(); 174 return err; 175 } 176 177 return 0; 178 } 179 180 static void mac_hid_stop_emulation(void) 181 { 182 input_unregister_handler(&mac_hid_emumouse_handler); 183 mac_hid_destroy_emumouse(); 184 } 185 186 static int mac_hid_toggle_emumouse(const struct ctl_table *table, int write, 187 void *buffer, size_t *lenp, loff_t *ppos) 188 { 189 int *valp = table->data; 190 int old_val = *valp; 191 int rc; 192 193 rc = mutex_lock_killable(&mac_hid_emumouse_mutex); 194 if (rc) 195 return rc; 196 197 rc = proc_dointvec(table, write, buffer, lenp, ppos); 198 199 if (rc == 0 && write && *valp != old_val) { 200 if (*valp == 1) 201 rc = mac_hid_start_emulation(); 202 else if (*valp == 0) 203 mac_hid_stop_emulation(); 204 else 205 rc = -EINVAL; 206 } 207 208 /* Restore the old value in case of error */ 209 if (rc) 210 *valp = old_val; 211 212 mutex_unlock(&mac_hid_emumouse_mutex); 213 214 return rc; 215 } 216 217 /* file(s) in /proc/sys/dev/mac_hid */ 218 static struct ctl_table mac_hid_files[] = { 219 { 220 .procname = "mouse_button_emulation", 221 .data = &mouse_emulate_buttons, 222 .maxlen = sizeof(int), 223 .mode = 0644, 224 .proc_handler = mac_hid_toggle_emumouse, 225 }, 226 { 227 .procname = "mouse_button2_keycode", 228 .data = &mouse_button2_keycode, 229 .maxlen = sizeof(int), 230 .mode = 0644, 231 .proc_handler = proc_dointvec, 232 }, 233 { 234 .procname = "mouse_button3_keycode", 235 .data = &mouse_button3_keycode, 236 .maxlen = sizeof(int), 237 .mode = 0644, 238 .proc_handler = proc_dointvec, 239 }, 240 }; 241 242 static struct ctl_table_header *mac_hid_sysctl_header; 243 244 static int __init mac_hid_init(void) 245 { 246 mac_hid_sysctl_header = register_sysctl("dev/mac_hid", mac_hid_files); 247 if (!mac_hid_sysctl_header) 248 return -ENOMEM; 249 250 return 0; 251 } 252 module_init(mac_hid_init); 253 254 static void __exit mac_hid_exit(void) 255 { 256 unregister_sysctl_table(mac_hid_sysctl_header); 257 258 if (mouse_emulate_buttons) 259 mac_hid_stop_emulation(); 260 } 261 module_exit(mac_hid_exit); 262