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 MODULE_DESCRIPTION("Handykey Twiddler keyboard as a joystick driver");
  62 MODULE_LICENSE("GPL");
  63
  64 /*
  65  * Constants.
  66  */
  67
  68 #define TWIDJOY_MAX_LENGTH 5
  69
  70 static char *twidjoy_name = "Handykey Twiddler";
  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         if (twidjoy->idx == TWIDJOY_MAX_LENGTH) {
 110                 struct input_dev *dev = &twidjoy->dev;
 111                 unsigned char *data = twidjoy->data;
 112                 struct twidjoy_button_spec *bp;
 113                 int button_bits, abs_x, abs_y;
 114
 115                 button_bits = ((data[1] & 0x7f) << 7) | (data[0] & 0x7f);
 116
 117                 input_regs(dev, regs);
 118
 119                 for (bp = twidjoy_buttons; bp->bitmask; bp++) {
 120                         int value = (button_bits & (bp->bitmask << bp->bitshift)) >> bp->bitshift;
 121                         int i;
 122
 123                         for (i = 0; i < bp->bitmask; i++)
 124                                 input_report_key(dev, bp->buttons[i], i+1 == value);
 125                 }
 126
 127                 abs_x = ((data[4] & 0x07) << 5) | ((data[3] & 0x7C) >> 2);
 128                 if (data[4] & 0x08) abs_x -= 256;
 129
 130                 abs_y = ((data[3] & 0x01) << 7) | ((data[2] & 0x7F) >> 0);
 131                 if (data[3] & 0x02) abs_y -= 256;
 132
 133                 input_report_abs(dev, ABS_X, -abs_x);
 134                 input_report_abs(dev, ABS_Y, +abs_y);
 135
 136                 input_sync(dev);
 137         }
 138
 139         return;
 140 }
 141
 142 /*
 143  * twidjoy_interrupt() is called by the low level driver when characters
 144  * are ready for us. We then buffer them for further processing, or call the
 145  * packet processing routine.
 146  */
 147
 148 static irqreturn_t twidjoy_interrupt(struct serio *serio, unsigned char data, unsigned int flags, struct pt_regs *regs)
 149 {
 150         struct twidjoy *twidjoy = serio->private;
 151
 152         /* All Twiddler packets are 5 bytes. The fact that the first byte
 153          * has a MSB of 0 and all other bytes have a MSB of 1 can be used
 154          * to check and regain sync. */
 155
 156         if ((data & 0x80) == 0)
 157                 twidjoy->idx = 0;       /* this byte starts a new packet */
 158         else if (twidjoy->idx == 0)
 159                 return IRQ_HANDLED;     /* wrong MSB -- ignore this byte */
 160
 161         if (twidjoy->idx < TWIDJOY_MAX_LENGTH)
 162                 twidjoy->data[twidjoy->idx++] = data;
 163
 164         if (twidjoy->idx == TWIDJOY_MAX_LENGTH) {
 165                 twidjoy_process_packet(twidjoy, regs);
 166                 twidjoy->idx = 0;
 167         }
 168
 169         return IRQ_HANDLED;
 170 }
 171
 172 /*
 173  * twidjoy_disconnect() is the opposite of twidjoy_connect()
 174  */
 175
 176 static void twidjoy_disconnect(struct serio *serio)
 177 {
 178         struct twidjoy *twidjoy = serio->private;
 179         input_unregister_device(&twidjoy->dev);
 180         serio_close(serio);
 181         kfree(twidjoy);
 182 }
 183
 184 /*
 185  * twidjoy_connect() is the routine that is called when someone adds a
 186  * new serio device. It looks for the Twiddler, and if found, registers
 187  * it as an input device.
 188  */
 189
 190 static void twidjoy_connect(struct serio *serio, struct serio_driver *drv)
 191 {
 192         struct twidjoy_button_spec *bp;
 193         struct twidjoy *twidjoy;
 194         int i;
 195
 196         if (serio->type != (SERIO_RS232 | SERIO_TWIDJOY))
 197                 return;
 198
 199         if (!(twidjoy = kmalloc(sizeof(struct twidjoy), GFP_KERNEL)))
 200                 return;
 201
 202         memset(twidjoy, 0, sizeof(struct twidjoy));
 203
 204         sprintf(twidjoy->phys, "%s/input0", serio->phys);
 205
 206         init_input_dev(&twidjoy->dev);
 207         twidjoy->dev.name = twidjoy_name;
 208         twidjoy->dev.phys = twidjoy->phys;
 209         twidjoy->dev.id.bustype = BUS_RS232;
 210         twidjoy->dev.id.vendor = SERIO_TWIDJOY;
 211         twidjoy->dev.id.product = 0x0001;
 212         twidjoy->dev.id.version = 0x0100;
 213
 214         twidjoy->dev.evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
 215
 216         for (bp = twidjoy_buttons; bp->bitmask; bp++) {
 217                 for (i = 0; i < bp->bitmask; i++)
 218                         set_bit(bp->buttons[i], twidjoy->dev.keybit);
 219         }
 220
 221         twidjoy->dev.absbit[0] = BIT(ABS_X) | BIT(ABS_Y);
 222
 223         for (i = 0; i < 2; i++) {
 224                 twidjoy->dev.absmax[ABS_X+i] =  50;
 225                 twidjoy->dev.absmin[ABS_X+i] = -50;
 226
 227                 /* TODO: arndt 20010708: Are these values appropriate? */
 228                 twidjoy->dev.absfuzz[ABS_X+i] = 4;
 229                 twidjoy->dev.absflat[ABS_X+i] = 4;
 230         }
 231
 232         twidjoy->dev.private = twidjoy;
 233         serio->private = twidjoy;
 234
 235         if (serio_open(serio, drv)) {
 236                 kfree(twidjoy);
 237                 return;
 238         }
 239
 240         input_register_device(&twidjoy->dev);
 241
 242         printk(KERN_INFO "input: %s on %s\n", twidjoy_name, serio->phys);
 243 }
 244
 245 /*
 246  * The serio device structure.
 247  */
 248
 249 static struct serio_driver twidjoy_drv = {
 250         .driver         = {
 251                 .name   = "twidjoy",
 252         },
 253         .description    = DRIVER_DESC,
 254         .interrupt      = twidjoy_interrupt,
 255         .connect        = twidjoy_connect,
 256         .disconnect     = twidjoy_disconnect,
 257 };
 258
 259 /*
 260  * The functions for inserting/removing us as a module.
 261  */
 262
 263 int __init twidjoy_init(void)
 264 {
 265         serio_register_driver(&twidjoy_drv);
 266         return 0;
 267 }
 268
 269 void __exit twidjoy_exit(void)
 270 {
 271         serio_unregister_driver(&twidjoy_drv);
 272 }
 273
 274 module_init(twidjoy_init);
 275 module_exit(twidjoy_exit);