1/* 2 * Copyright (c) 2001 Arndt Schoenewald 3 * Copyright (c) 2000-2001 Vojtech Pavlik 4 * Copyright (c) 2000 Mark Fletcher 5 * 6 * Sponsored by Quelltext AG (http://www.quelltext-ag.de), Dortmund, Germany 7 */ 8 9/* 10 * Driver to use Handykey's Twiddler (the first edition, i.e. the one with 11 * the RS232 interface) as a joystick under Linux 12 * 13 * The Twiddler is a one-handed chording keyboard featuring twelve buttons on 14 * the front, six buttons on the top, and a built-in tilt sensor. The buttons 15 * on the front, which are grouped as four rows of three buttons, are pressed 16 * by the four fingers (this implies only one button per row can be held down 17 * at the same time) and the buttons on the top are for the thumb. The tilt 18 * sensor delivers X and Y axis data depending on how the Twiddler is held. 19 * Additional information can be found at http://www.handykey.com. 20 * 21 * This driver does not use the Twiddler for its intended purpose, i.e. as 22 * a chording keyboard, but as a joystick: pressing and releasing a button 23 * immediately sends a corresponding button event, and tilting it generates 24 * corresponding ABS_X and ABS_Y events. This turns the Twiddler into a game 25 * controller with amazing 18 buttons :-) 26 * 27 * Note: The Twiddler2 (the successor of the Twiddler that connects directly 28 * to the PS/2 keyboard and mouse ports) is NOT supported by this driver! 29 * 30 * For questions or feedback regarding this driver module please contact: 31 * Arndt Schoenewald <arndt@quelltext.com> 32 */ 33 34/* 35 * This program is free software; you can redistribute it and/or modify 36 * it under the terms of the GNU General Public License as published by 37 * the Free Software Foundation; either version 2 of the License, or 38 * (at your option) any later version. 39 * 40 * This program is distributed in the hope that it will be useful, 41 * but WITHOUT ANY WARRANTY; without even the implied warranty of 42 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 43 * GNU General Public License for more details. 44 * 45 * You should have received a copy of the GNU General Public License 46 * along with this program; if not, write to the Free Software 47 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 48 */ 49 50#include <linux/kernel.h> 51#include <linux/module.h> 52#include <linux/slab.h> 53#include <linux/input.h> 54#include <linux/serio.h> 55#include <linux/init.h> 56 57#define DRIVER_DESC "Handykey Twiddler keyboard as a joystick driver" 58 59MODULE_DESCRIPTION(DRIVER_DESC); 60MODULE_LICENSE("GPL"); 61 62/* 63 * Constants. 64 */ 65 66#define TWIDJOY_MAX_LENGTH 5 67 68static struct twidjoy_button_spec { 69 int bitshift; 70 int bitmask; 71 int buttons[3]; 72} 73twidjoy_buttons[] = { 74 { 0, 3, { BTN_A, BTN_B, BTN_C } }, 75 { 2, 3, { BTN_X, BTN_Y, BTN_Z } }, 76 { 4, 3, { BTN_TL, BTN_TR, BTN_TR2 } }, 77 { 6, 3, { BTN_SELECT, BTN_START, BTN_MODE } }, 78 { 8, 1, { BTN_BASE5 } }, 79 { 9, 1, { BTN_BASE } }, 80 { 10, 1, { BTN_BASE3 } }, 81 { 11, 1, { BTN_BASE4 } }, 82 { 12, 1, { BTN_BASE2 } }, 83 { 13, 1, { BTN_BASE6 } }, 84 { 0, 0, { 0 } } 85}; 86 87/* 88 * Per-Twiddler data. 89 */ 90 91struct twidjoy { 92 struct input_dev *dev; 93 int idx; 94 unsigned char data[TWIDJOY_MAX_LENGTH]; 95 char phys[32]; 96}; 97 98/* 99 * twidjoy_process_packet() decodes packets the driver receives from the 100 * Twiddler. It updates the data accordingly. 101 */ 102 103static void twidjoy_process_packet(struct twidjoy *twidjoy) 104{ 105 struct input_dev *dev = twidjoy->dev; 106 unsigned char *data = twidjoy->data; 107 struct twidjoy_button_spec *bp; 108 int button_bits, abs_x, abs_y; 109 110 button_bits = ((data[1] & 0x7f) << 7) | (data[0] & 0x7f); 111 112 for (bp = twidjoy_buttons; bp->bitmask; bp++) { 113 int value = (button_bits & (bp->bitmask << bp->bitshift)) >> bp->bitshift; 114 int i; 115 116 for (i = 0; i < bp->bitmask; i++) 117 input_report_key(dev, bp->buttons[i], i+1 == value); 118 } 119 120 abs_x = ((data[4] & 0x07) << 5) | ((data[3] & 0x7C) >> 2); 121 if (data[4] & 0x08) abs_x -= 256; 122 123 abs_y = ((data[3] & 0x01) << 7) | ((data[2] & 0x7F) >> 0); 124 if (data[3] & 0x02) abs_y -= 256; 125 126 input_report_abs(dev, ABS_X, -abs_x); 127 input_report_abs(dev, ABS_Y, +abs_y); 128 129 input_sync(dev); 130} 131 132/* 133 * twidjoy_interrupt() is called by the low level driver when characters 134 * are ready for us. We then buffer them for further processing, or call the 135 * packet processing routine. 136 */ 137 138static irqreturn_t twidjoy_interrupt(struct serio *serio, unsigned char data, unsigned int flags) 139{ 140 struct twidjoy *twidjoy = serio_get_drvdata(serio); 141 142 /* All Twiddler packets are 5 bytes. The fact that the first byte 143 * has a MSB of 0 and all other bytes have a MSB of 1 can be used 144 * to check and regain sync. */ 145 146 if ((data & 0x80) == 0) 147 twidjoy->idx = 0; /* this byte starts a new packet */ 148 else if (twidjoy->idx == 0) 149 return IRQ_HANDLED; /* wrong MSB -- ignore this byte */ 150 151 if (twidjoy->idx < TWIDJOY_MAX_LENGTH) 152 twidjoy->data[twidjoy->idx++] = data; 153 154 if (twidjoy->idx == TWIDJOY_MAX_LENGTH) { 155 twidjoy_process_packet(twidjoy); 156 twidjoy->idx = 0; 157 } 158 159 return IRQ_HANDLED; 160} 161 162/* 163 * twidjoy_disconnect() is the opposite of twidjoy_connect() 164 */ 165 166static void twidjoy_disconnect(struct serio *serio) 167{ 168 struct twidjoy *twidjoy = serio_get_drvdata(serio); 169 170 serio_close(serio); 171 serio_set_drvdata(serio, NULL); 172 input_unregister_device(twidjoy->dev); 173 kfree(twidjoy); 174} 175 176/* 177 * twidjoy_connect() is the routine that is called when someone adds a 178 * new serio device. It looks for the Twiddler, and if found, registers 179 * it as an input device. 180 */ 181 182static int twidjoy_connect(struct serio *serio, struct serio_driver *drv) 183{ 184 struct twidjoy_button_spec *bp; 185 struct twidjoy *twidjoy; 186 struct input_dev *input_dev; 187 int err = -ENOMEM; 188 int i; 189 190 twidjoy = kzalloc(sizeof(struct twidjoy), GFP_KERNEL); 191 input_dev = input_allocate_device(); 192 if (!twidjoy || !input_dev) 193 goto fail1; 194 195 twidjoy->dev = input_dev; 196 snprintf(twidjoy->phys, sizeof(twidjoy->phys), "%s/input0", serio->phys); 197 198 input_dev->name = "Handykey Twiddler"; 199 input_dev->phys = twidjoy->phys; 200 input_dev->id.bustype = BUS_RS232; 201 input_dev->id.vendor = SERIO_TWIDJOY; 202 input_dev->id.product = 0x0001; 203 input_dev->id.version = 0x0100; 204 input_dev->dev.parent = &serio->dev; 205 206 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); 207 input_set_abs_params(input_dev, ABS_X, -50, 50, 4, 4); 208 input_set_abs_params(input_dev, ABS_Y, -50, 50, 4, 4); 209 210 for (bp = twidjoy_buttons; bp->bitmask; bp++) 211 for (i = 0; i < bp->bitmask; i++) 212 set_bit(bp->buttons[i], input_dev->keybit); 213 214 serio_set_drvdata(serio, twidjoy); 215 216 err = serio_open(serio, drv); 217 if (err) 218 goto fail2; 219 220 err = input_register_device(twidjoy->dev); 221 if (err) 222 goto fail3; 223 224 return 0; 225 226 fail3: serio_close(serio); 227 fail2: serio_set_drvdata(serio, NULL); 228 fail1: input_free_device(input_dev); 229 kfree(twidjoy); 230 return err; 231} 232 233/* 234 * The serio driver structure. 235 */ 236 237static struct serio_device_id twidjoy_serio_ids[] = { 238 { 239 .type = SERIO_RS232, 240 .proto = SERIO_TWIDJOY, 241 .id = SERIO_ANY, 242 .extra = SERIO_ANY, 243 }, 244 { 0 } 245}; 246 247MODULE_DEVICE_TABLE(serio, twidjoy_serio_ids); 248 249static struct serio_driver twidjoy_drv = { 250 .driver = { 251 .name = "twidjoy", 252 }, 253 .description = DRIVER_DESC, 254 .id_table = twidjoy_serio_ids, 255 .interrupt = twidjoy_interrupt, 256 .connect = twidjoy_connect, 257 .disconnect = twidjoy_disconnect, 258}; 259 260/* 261 * The functions for inserting/removing us as a module. 262 */ 263 264static int __init twidjoy_init(void) 265{ 266 return serio_register_driver(&twidjoy_drv); 267} 268 269static void __exit twidjoy_exit(void) 270{ 271 serio_unregister_driver(&twidjoy_drv); 272} 273 274module_init(twidjoy_init); 275module_exit(twidjoy_exit); 276