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 56 #define DRIVER_DESC "Handykey Twiddler keyboard as a joystick driver" 57 58 MODULE_DESCRIPTION(DRIVER_DESC); 59 MODULE_LICENSE("GPL"); 60 61 /* 62 * Constants. 63 */ 64 65 #define TWIDJOY_MAX_LENGTH 5 66 67 static struct twidjoy_button_spec { 68 int bitshift; 69 int bitmask; 70 int buttons[3]; 71 } 72 twidjoy_buttons[] = { 73 { 0, 3, { BTN_A, BTN_B, BTN_C } }, 74 { 2, 3, { BTN_X, BTN_Y, BTN_Z } }, 75 { 4, 3, { BTN_TL, BTN_TR, BTN_TR2 } }, 76 { 6, 3, { BTN_SELECT, BTN_START, BTN_MODE } }, 77 { 8, 1, { BTN_BASE5 } }, 78 { 9, 1, { BTN_BASE } }, 79 { 10, 1, { BTN_BASE3 } }, 80 { 11, 1, { BTN_BASE4 } }, 81 { 12, 1, { BTN_BASE2 } }, 82 { 13, 1, { BTN_BASE6 } }, 83 { 0, 0, { 0 } } 84 }; 85 86 /* 87 * Per-Twiddler data. 88 */ 89 90 struct twidjoy { 91 struct input_dev *dev; 92 int idx; 93 unsigned char data[TWIDJOY_MAX_LENGTH]; 94 char phys[32]; 95 }; 96 97 /* 98 * twidjoy_process_packet() decodes packets the driver receives from the 99 * Twiddler. It updates the data accordingly. 100 */ 101 102 static void twidjoy_process_packet(struct twidjoy *twidjoy) 103 { 104 struct input_dev *dev = twidjoy->dev; 105 unsigned char *data = twidjoy->data; 106 struct twidjoy_button_spec *bp; 107 int button_bits, abs_x, abs_y; 108 109 button_bits = ((data[1] & 0x7f) << 7) | (data[0] & 0x7f); 110 111 for (bp = twidjoy_buttons; bp->bitmask; bp++) { 112 int value = (button_bits & (bp->bitmask << bp->bitshift)) >> bp->bitshift; 113 int i; 114 115 for (i = 0; i < bp->bitmask; i++) 116 input_report_key(dev, bp->buttons[i], i+1 == value); 117 } 118 119 abs_x = ((data[4] & 0x07) << 5) | ((data[3] & 0x7C) >> 2); 120 if (data[4] & 0x08) abs_x -= 256; 121 122 abs_y = ((data[3] & 0x01) << 7) | ((data[2] & 0x7F) >> 0); 123 if (data[3] & 0x02) abs_y -= 256; 124 125 input_report_abs(dev, ABS_X, -abs_x); 126 input_report_abs(dev, ABS_Y, +abs_y); 127 128 input_sync(dev); 129 } 130 131 /* 132 * twidjoy_interrupt() is called by the low level driver when characters 133 * are ready for us. We then buffer them for further processing, or call the 134 * packet processing routine. 135 */ 136 137 static irqreturn_t twidjoy_interrupt(struct serio *serio, unsigned char data, unsigned int flags) 138 { 139 struct twidjoy *twidjoy = serio_get_drvdata(serio); 140 141 /* All Twiddler packets are 5 bytes. The fact that the first byte 142 * has a MSB of 0 and all other bytes have a MSB of 1 can be used 143 * to check and regain sync. */ 144 145 if ((data & 0x80) == 0) 146 twidjoy->idx = 0; /* this byte starts a new packet */ 147 else if (twidjoy->idx == 0) 148 return IRQ_HANDLED; /* wrong MSB -- ignore this byte */ 149 150 if (twidjoy->idx < TWIDJOY_MAX_LENGTH) 151 twidjoy->data[twidjoy->idx++] = data; 152 153 if (twidjoy->idx == TWIDJOY_MAX_LENGTH) { 154 twidjoy_process_packet(twidjoy); 155 twidjoy->idx = 0; 156 } 157 158 return IRQ_HANDLED; 159 } 160 161 /* 162 * twidjoy_disconnect() is the opposite of twidjoy_connect() 163 */ 164 165 static void twidjoy_disconnect(struct serio *serio) 166 { 167 struct twidjoy *twidjoy = serio_get_drvdata(serio); 168 169 serio_close(serio); 170 serio_set_drvdata(serio, NULL); 171 input_unregister_device(twidjoy->dev); 172 kfree(twidjoy); 173 } 174 175 /* 176 * twidjoy_connect() is the routine that is called when someone adds a 177 * new serio device. It looks for the Twiddler, and if found, registers 178 * it as an input device. 179 */ 180 181 static int twidjoy_connect(struct serio *serio, struct serio_driver *drv) 182 { 183 struct twidjoy_button_spec *bp; 184 struct twidjoy *twidjoy; 185 struct input_dev *input_dev; 186 int err = -ENOMEM; 187 int i; 188 189 twidjoy = kzalloc(sizeof(struct twidjoy), GFP_KERNEL); 190 input_dev = input_allocate_device(); 191 if (!twidjoy || !input_dev) 192 goto fail1; 193 194 twidjoy->dev = input_dev; 195 snprintf(twidjoy->phys, sizeof(twidjoy->phys), "%s/input0", serio->phys); 196 197 input_dev->name = "Handykey Twiddler"; 198 input_dev->phys = twidjoy->phys; 199 input_dev->id.bustype = BUS_RS232; 200 input_dev->id.vendor = SERIO_TWIDJOY; 201 input_dev->id.product = 0x0001; 202 input_dev->id.version = 0x0100; 203 input_dev->dev.parent = &serio->dev; 204 205 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); 206 input_set_abs_params(input_dev, ABS_X, -50, 50, 4, 4); 207 input_set_abs_params(input_dev, ABS_Y, -50, 50, 4, 4); 208 209 for (bp = twidjoy_buttons; bp->bitmask; bp++) 210 for (i = 0; i < bp->bitmask; i++) 211 set_bit(bp->buttons[i], input_dev->keybit); 212 213 serio_set_drvdata(serio, twidjoy); 214 215 err = serio_open(serio, drv); 216 if (err) 217 goto fail2; 218 219 err = input_register_device(twidjoy->dev); 220 if (err) 221 goto fail3; 222 223 return 0; 224 225 fail3: serio_close(serio); 226 fail2: serio_set_drvdata(serio, NULL); 227 fail1: input_free_device(input_dev); 228 kfree(twidjoy); 229 return err; 230 } 231 232 /* 233 * The serio driver structure. 234 */ 235 236 static const struct serio_device_id twidjoy_serio_ids[] = { 237 { 238 .type = SERIO_RS232, 239 .proto = SERIO_TWIDJOY, 240 .id = SERIO_ANY, 241 .extra = SERIO_ANY, 242 }, 243 { 0 } 244 }; 245 246 MODULE_DEVICE_TABLE(serio, twidjoy_serio_ids); 247 248 static struct serio_driver twidjoy_drv = { 249 .driver = { 250 .name = "twidjoy", 251 }, 252 .description = DRIVER_DESC, 253 .id_table = twidjoy_serio_ids, 254 .interrupt = twidjoy_interrupt, 255 .connect = twidjoy_connect, 256 .disconnect = twidjoy_disconnect, 257 }; 258 259 module_serio_driver(twidjoy_drv); 260