1 /* 2 * $Id: twidjoy.c,v 1.5 2002/01/22 20:31:53 vojtech Exp $ 3 * 4 * derived from CVS-ID "stinger.c,v 1.5 2001/05/29 12:57:18 vojtech Exp" 5 * 6 * Copyright (c) 2001 Arndt Schoenewald 7 * Copyright (c) 2000-2001 Vojtech Pavlik 8 * Copyright (c) 2000 Mark Fletcher 9 * 10 * Sponsored by Quelltext AG (http://www.quelltext-ag.de), Dortmund, Germany 11 */ 12 13 /* 14 * Driver to use Handykey's Twiddler (the first edition, i.e. the one with 15 * the RS232 interface) as a joystick under Linux 16 * 17 * The Twiddler is a one-handed chording keyboard featuring twelve buttons on 18 * the front, six buttons on the top, and a built-in tilt sensor. The buttons 19 * on the front, which are grouped as four rows of three buttons, are pressed 20 * by the four fingers (this implies only one button per row can be held down 21 * at the same time) and the buttons on the top are for the thumb. The tilt 22 * sensor delivers X and Y axis data depending on how the Twiddler is held. 23 * Additional information can be found at http://www.handykey.com. 24 * 25 * This driver does not use the Twiddler for its intended purpose, i.e. as 26 * a chording keyboard, but as a joystick: pressing and releasing a button 27 * immediately sends a corresponding button event, and tilting it generates 28 * corresponding ABS_X and ABS_Y events. This turns the Twiddler into a game 29 * controller with amazing 18 buttons :-) 30 * 31 * Note: The Twiddler2 (the successor of the Twiddler that connects directly 32 * to the PS/2 keyboard and mouse ports) is NOT supported by this driver! 33 * 34 * For questions or feedback regarding this driver module please contact: 35 * Arndt Schoenewald <arndt@quelltext.com> 36 */ 37 38 /* 39 * This program is free software; you can redistribute it and/or modify 40 * it under the terms of the GNU General Public License as published by 41 * the Free Software Foundation; either version 2 of the License, or 42 * (at your option) any later version. 43 * 44 * This program is distributed in the hope that it will be useful, 45 * but WITHOUT ANY WARRANTY; without even the implied warranty of 46 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 47 * GNU General Public License for more details. 48 * 49 * You should have received a copy of the GNU General Public License 50 * along with this program; if not, write to the Free Software 51 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 52 */ 53 54 #include <linux/kernel.h> 55 #include <linux/module.h> 56 #include <linux/slab.h> 57 #include <linux/input.h> 58 #include <linux/serio.h> 59 #include <linux/init.h> 60 61 #define DRIVER_DESC "Handykey Twiddler keyboard as a joystick driver" 62 63 MODULE_DESCRIPTION(DRIVER_DESC); 64 MODULE_LICENSE("GPL"); 65 66 /* 67 * Constants. 68 */ 69 70 #define TWIDJOY_MAX_LENGTH 5 71 72 static struct twidjoy_button_spec { 73 int bitshift; 74 int bitmask; 75 int buttons[3]; 76 } 77 twidjoy_buttons[] = { 78 { 0, 3, { BTN_A, BTN_B, BTN_C } }, 79 { 2, 3, { BTN_X, BTN_Y, BTN_Z } }, 80 { 4, 3, { BTN_TL, BTN_TR, BTN_TR2 } }, 81 { 6, 3, { BTN_SELECT, BTN_START, BTN_MODE } }, 82 { 8, 1, { BTN_BASE5 } }, 83 { 9, 1, { BTN_BASE } }, 84 { 10, 1, { BTN_BASE3 } }, 85 { 11, 1, { BTN_BASE4 } }, 86 { 12, 1, { BTN_BASE2 } }, 87 { 13, 1, { BTN_BASE6 } }, 88 { 0, 0, { 0 } } 89 }; 90 91 /* 92 * Per-Twiddler data. 93 */ 94 95 struct twidjoy { 96 struct input_dev *dev; 97 int idx; 98 unsigned char data[TWIDJOY_MAX_LENGTH]; 99 char phys[32]; 100 }; 101 102 /* 103 * twidjoy_process_packet() decodes packets the driver receives from the 104 * Twiddler. It updates the data accordingly. 105 */ 106 107 static void twidjoy_process_packet(struct twidjoy *twidjoy, struct pt_regs *regs) 108 { 109 struct input_dev *dev = twidjoy->dev; 110 unsigned char *data = twidjoy->data; 111 struct twidjoy_button_spec *bp; 112 int button_bits, abs_x, abs_y; 113 114 button_bits = ((data[1] & 0x7f) << 7) | (data[0] & 0x7f); 115 116 input_regs(dev, regs); 117 118 for (bp = twidjoy_buttons; bp->bitmask; bp++) { 119 int value = (button_bits & (bp->bitmask << bp->bitshift)) >> bp->bitshift; 120 int i; 121 122 for (i = 0; i < bp->bitmask; i++) 123 input_report_key(dev, bp->buttons[i], i+1 == value); 124 } 125 126 abs_x = ((data[4] & 0x07) << 5) | ((data[3] & 0x7C) >> 2); 127 if (data[4] & 0x08) abs_x -= 256; 128 129 abs_y = ((data[3] & 0x01) << 7) | ((data[2] & 0x7F) >> 0); 130 if (data[3] & 0x02) abs_y -= 256; 131 132 input_report_abs(dev, ABS_X, -abs_x); 133 input_report_abs(dev, ABS_Y, +abs_y); 134 135 input_sync(dev); 136 } 137 138 /* 139 * twidjoy_interrupt() is called by the low level driver when characters 140 * are ready for us. We then buffer them for further processing, or call the 141 * packet processing routine. 142 */ 143 144 static irqreturn_t twidjoy_interrupt(struct serio *serio, unsigned char data, unsigned int flags, struct pt_regs *regs) 145 { 146 struct twidjoy *twidjoy = serio_get_drvdata(serio); 147 148 /* All Twiddler packets are 5 bytes. The fact that the first byte 149 * has a MSB of 0 and all other bytes have a MSB of 1 can be used 150 * to check and regain sync. */ 151 152 if ((data & 0x80) == 0) 153 twidjoy->idx = 0; /* this byte starts a new packet */ 154 else if (twidjoy->idx == 0) 155 return IRQ_HANDLED; /* wrong MSB -- ignore this byte */ 156 157 if (twidjoy->idx < TWIDJOY_MAX_LENGTH) 158 twidjoy->data[twidjoy->idx++] = data; 159 160 if (twidjoy->idx == TWIDJOY_MAX_LENGTH) { 161 twidjoy_process_packet(twidjoy, regs); 162 twidjoy->idx = 0; 163 } 164 165 return IRQ_HANDLED; 166 } 167 168 /* 169 * twidjoy_disconnect() is the opposite of twidjoy_connect() 170 */ 171 172 static void twidjoy_disconnect(struct serio *serio) 173 { 174 struct twidjoy *twidjoy = serio_get_drvdata(serio); 175 176 serio_close(serio); 177 serio_set_drvdata(serio, NULL); 178 input_unregister_device(twidjoy->dev); 179 kfree(twidjoy); 180 } 181 182 /* 183 * twidjoy_connect() is the routine that is called when someone adds a 184 * new serio device. It looks for the Twiddler, and if found, registers 185 * it as an input device. 186 */ 187 188 static int twidjoy_connect(struct serio *serio, struct serio_driver *drv) 189 { 190 struct twidjoy_button_spec *bp; 191 struct twidjoy *twidjoy; 192 struct input_dev *input_dev; 193 int err = -ENOMEM; 194 int i; 195 196 twidjoy = kzalloc(sizeof(struct twidjoy), GFP_KERNEL); 197 input_dev = input_allocate_device(); 198 if (!twidjoy || !input_dev) 199 goto fail; 200 201 twidjoy->dev = input_dev; 202 sprintf(twidjoy->phys, "%s/input0", serio->phys); 203 204 input_dev->name = "Handykey Twiddler"; 205 input_dev->phys = twidjoy->phys; 206 input_dev->id.bustype = BUS_RS232; 207 input_dev->id.vendor = SERIO_TWIDJOY; 208 input_dev->id.product = 0x0001; 209 input_dev->id.version = 0x0100; 210 input_dev->cdev.dev = &serio->dev; 211 input_dev->private = twidjoy; 212 213 input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS); 214 input_dev->absbit[0] = BIT(ABS_X) | BIT(ABS_Y); 215 input_set_abs_params(input_dev, ABS_X, -50, 50, 4, 4); 216 input_set_abs_params(input_dev, ABS_Y, -50, 50, 4, 4); 217 218 for (bp = twidjoy_buttons; bp->bitmask; bp++) 219 for (i = 0; i < bp->bitmask; i++) 220 set_bit(bp->buttons[i], input_dev->keybit); 221 222 serio_set_drvdata(serio, twidjoy); 223 224 err = serio_open(serio, drv); 225 if (err) 226 goto fail; 227 228 input_register_device(twidjoy->dev); 229 return 0; 230 231 fail: serio_set_drvdata(serio, NULL); 232 input_free_device(input_dev); 233 kfree(twidjoy); 234 return err; 235 } 236 237 /* 238 * The serio driver structure. 239 */ 240 241 static struct serio_device_id twidjoy_serio_ids[] = { 242 { 243 .type = SERIO_RS232, 244 .proto = SERIO_TWIDJOY, 245 .id = SERIO_ANY, 246 .extra = SERIO_ANY, 247 }, 248 { 0 } 249 }; 250 251 MODULE_DEVICE_TABLE(serio, twidjoy_serio_ids); 252 253 static struct serio_driver twidjoy_drv = { 254 .driver = { 255 .name = "twidjoy", 256 }, 257 .description = DRIVER_DESC, 258 .id_table = twidjoy_serio_ids, 259 .interrupt = twidjoy_interrupt, 260 .connect = twidjoy_connect, 261 .disconnect = twidjoy_disconnect, 262 }; 263 264 /* 265 * The functions for inserting/removing us as a module. 266 */ 267 268 int __init twidjoy_init(void) 269 { 270 serio_register_driver(&twidjoy_drv); 271 return 0; 272 } 273 274 void __exit twidjoy_exit(void) 275 { 276 serio_unregister_driver(&twidjoy_drv); 277 } 278 279 module_init(twidjoy_init); 280 module_exit(twidjoy_exit); 281