drivers/input/joystick/twidjoy.c

   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 char *twidjoy_name = "Handykey Twiddler";
  73
  74 static struct twidjoy_button_spec {
  75         int bitshift;
  76         int bitmask;
  77         int buttons[3];
  78 }
  79 twidjoy_buttons[] = {
  80         {  0, 3, { BTN_A,      BTN_B,     BTN_C    } },
  81         {  2, 3, { BTN_X,      BTN_Y,     BTN_Z    } },
  82         {  4, 3, { BTN_TL,     BTN_TR,    BTN_TR2  } },
  83         {  6, 3, { BTN_SELECT, BTN_START, BTN_MODE } },
  84         {  8, 1, { BTN_BASE5                       } },
  85         {  9, 1, { BTN_BASE                        } },
  86         { 10, 1, { BTN_BASE3                       } },
  87         { 11, 1, { BTN_BASE4                       } },
  88         { 12, 1, { BTN_BASE2                       } },
  89         { 13, 1, { BTN_BASE6                       } },
  90         { 0,  0, { 0                               } }
  91 };
  92
  93 /*
  94  * Per-Twiddler data.
  95  */
  96
  97 struct twidjoy {
  98         struct input_dev dev;
  99         int idx;
 100         unsigned char data[TWIDJOY_MAX_LENGTH];
 101         char phys[32];
 102 };
 103
 104 /*
 105  * twidjoy_process_packet() decodes packets the driver receives from the
 106  * Twiddler. It updates the data accordingly.
 107  */
 108
 109 static void twidjoy_process_packet(struct twidjoy *twidjoy, struct pt_regs *regs)
 110 {
 111         if (twidjoy->idx == TWIDJOY_MAX_LENGTH) {
 112                 struct input_dev *dev = &twidjoy->dev;
 113                 unsigned char *data = twidjoy->data;
 114                 struct twidjoy_button_spec *bp;
 115                 int button_bits, abs_x, abs_y;
 116
 117                 button_bits = ((data[1] & 0x7f) << 7) | (data[0] & 0x7f);
 118
 119                 input_regs(dev, regs);
 120
 121                 for (bp = twidjoy_buttons; bp->bitmask; bp++) {
 122                         int value = (button_bits & (bp->bitmask << bp->bitshift)) >> bp->bitshift;
 123                         int i;
 124
 125                         for (i = 0; i < bp->bitmask; i++)
 126                                 input_report_key(dev, bp->buttons[i], i+1 == value);
 127                 }
 128
 129                 abs_x = ((data[4] & 0x07) << 5) | ((data[3] & 0x7C) >> 2);
 130                 if (data[4] & 0x08) abs_x -= 256;
 131
 132                 abs_y = ((data[3] & 0x01) << 7) | ((data[2] & 0x7F) >> 0);
 133                 if (data[3] & 0x02) abs_y -= 256;
 134
 135                 input_report_abs(dev, ABS_X, -abs_x);
 136                 input_report_abs(dev, ABS_Y, +abs_y);
 137
 138                 input_sync(dev);
 139         }
 140
 141         return;
 142 }
 143
 144 /*
 145  * twidjoy_interrupt() is called by the low level driver when characters
 146  * are ready for us. We then buffer them for further processing, or call the
 147  * packet processing routine.
 148  */
 149
 150 static irqreturn_t twidjoy_interrupt(struct serio *serio, unsigned char data, unsigned int flags, struct pt_regs *regs)
 151 {
 152         struct twidjoy *twidjoy = serio_get_drvdata(serio);
 153
 154         /* All Twiddler packets are 5 bytes. The fact that the first byte
 155          * has a MSB of 0 and all other bytes have a MSB of 1 can be used
 156          * to check and regain sync. */
 157
 158         if ((data & 0x80) == 0)
 159                 twidjoy->idx = 0;       /* this byte starts a new packet */
 160         else if (twidjoy->idx == 0)
 161                 return IRQ_HANDLED;     /* wrong MSB -- ignore this byte */
 162
 163         if (twidjoy->idx < TWIDJOY_MAX_LENGTH)
 164                 twidjoy->data[twidjoy->idx++] = data;
 165
 166         if (twidjoy->idx == TWIDJOY_MAX_LENGTH) {
 167                 twidjoy_process_packet(twidjoy, regs);
 168                 twidjoy->idx = 0;
 169         }
 170
 171         return IRQ_HANDLED;
 172 }
 173
 174 /*
 175  * twidjoy_disconnect() is the opposite of twidjoy_connect()
 176  */
 177
 178 static void twidjoy_disconnect(struct serio *serio)
 179 {
 180         struct twidjoy *twidjoy = serio_get_drvdata(serio);
 181
 182         input_unregister_device(&twidjoy->dev);
 183         serio_close(serio);
 184         serio_set_drvdata(serio, NULL);
 185         kfree(twidjoy);
 186 }
 187
 188 /*
 189  * twidjoy_connect() is the routine that is called when someone adds a
 190  * new serio device. It looks for the Twiddler, and if found, registers
 191  * it as an input device.
 192  */
 193
 194 static int twidjoy_connect(struct serio *serio, struct serio_driver *drv)
 195 {
 196         struct twidjoy_button_spec *bp;
 197         struct twidjoy *twidjoy;
 198         int i;
 199         int err;
 200
 201         if (!(twidjoy = kmalloc(sizeof(struct twidjoy), GFP_KERNEL)))
 202                 return -ENOMEM;
 203
 204         memset(twidjoy, 0, sizeof(struct twidjoy));
 205
 206         sprintf(twidjoy->phys, "%s/input0", serio->phys);
 207
 208         init_input_dev(&twidjoy->dev);
 209         twidjoy->dev.name = twidjoy_name;
 210         twidjoy->dev.phys = twidjoy->phys;
 211         twidjoy->dev.id.bustype = BUS_RS232;
 212         twidjoy->dev.id.vendor = SERIO_TWIDJOY;
 213         twidjoy->dev.id.product = 0x0001;
 214         twidjoy->dev.id.version = 0x0100;
 215         twidjoy->dev.dev = &serio->dev;
 216
 217         twidjoy->dev.evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
 218
 219         for (bp = twidjoy_buttons; bp->bitmask; bp++) {
 220                 for (i = 0; i < bp->bitmask; i++)
 221                         set_bit(bp->buttons[i], twidjoy->dev.keybit);
 222         }
 223
 224         twidjoy->dev.absbit[0] = BIT(ABS_X) | BIT(ABS_Y);
 225
 226         for (i = 0; i < 2; i++) {
 227                 twidjoy->dev.absmax[ABS_X+i] =  50;
 228                 twidjoy->dev.absmin[ABS_X+i] = -50;
 229
 230                 /* TODO: arndt 20010708: Are these values appropriate? */
 231                 twidjoy->dev.absfuzz[ABS_X+i] = 4;
 232                 twidjoy->dev.absflat[ABS_X+i] = 4;
 233         }
 234
 235         twidjoy->dev.private = twidjoy;
 236
 237         serio_set_drvdata(serio, twidjoy);
 238
 239         err = serio_open(serio, drv);
 240         if (err) {
 241                 serio_set_drvdata(serio, NULL);
 242                 kfree(twidjoy);
 243                 return err;
 244         }
 245
 246         input_register_device(&twidjoy->dev);
 247
 248         printk(KERN_INFO "input: %s on %s\n", twidjoy_name, serio->phys);
 249
 250         return 0;
 251 }
 252
 253 /*
 254  * The serio driver structure.
 255  */
 256
 257 static struct serio_device_id twidjoy_serio_ids[] = {
 258         {
 259                 .type   = SERIO_RS232,
 260                 .proto  = SERIO_TWIDJOY,
 261                 .id     = SERIO_ANY,
 262                 .extra  = SERIO_ANY,
 263         },
 264         { 0 }
 265 };
 266
 267 MODULE_DEVICE_TABLE(serio, twidjoy_serio_ids);
 268
 269 static struct serio_driver twidjoy_drv = {
 270         .driver         = {
 271                 .name   = "twidjoy",
 272         },
 273         .description    = DRIVER_DESC,
 274         .id_table       = twidjoy_serio_ids,
 275         .interrupt      = twidjoy_interrupt,
 276         .connect        = twidjoy_connect,
 277         .disconnect     = twidjoy_disconnect,
 278 };
 279
 280 /*
 281  * The functions for inserting/removing us as a module.
 282  */
 283
 284 int __init twidjoy_init(void)
 285 {
 286         serio_register_driver(&twidjoy_drv);
 287         return 0;
 288 }
 289
 290 void __exit twidjoy_exit(void)
 291 {
 292         serio_unregister_driver(&twidjoy_drv);
 293 }
 294
 295 module_init(twidjoy_init);
 296 module_exit(twidjoy_exit);