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 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)
 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         for (bp = twidjoy_buttons; bp->bitmask; bp++) {
 117                 int value = (button_bits & (bp->bitmask << bp->bitshift)) >> bp->bitshift;
 118                 int i;
 119
 120                 for (i = 0; i < bp->bitmask; i++)
 121                         input_report_key(dev, bp->buttons[i], i+1 == value);
 122         }
 123
 124         abs_x = ((data[4] & 0x07) << 5) | ((data[3] & 0x7C) >> 2);
 125         if (data[4] & 0x08) abs_x -= 256;
 126
 127         abs_y = ((data[3] & 0x01) << 7) | ((data[2] & 0x7F) >> 0);
 128         if (data[3] & 0x02) abs_y -= 256;
 129
 130         input_report_abs(dev, ABS_X, -abs_x);
 131         input_report_abs(dev, ABS_Y, +abs_y);
 132
 133         input_sync(dev);
 134 }
 135
 136 /*
 137  * twidjoy_interrupt() is called by the low level driver when characters
 138  * are ready for us. We then buffer them for further processing, or call the
 139  * packet processing routine.
 140  */
 141
 142 static irqreturn_t twidjoy_interrupt(struct serio *serio, unsigned char data, unsigned int flags)
 143 {
 144         struct twidjoy *twidjoy = serio_get_drvdata(serio);
 145
 146         /* All Twiddler packets are 5 bytes. The fact that the first byte
 147          * has a MSB of 0 and all other bytes have a MSB of 1 can be used
 148          * to check and regain sync. */
 149
 150         if ((data & 0x80) == 0)
 151                 twidjoy->idx = 0;       /* this byte starts a new packet */
 152         else if (twidjoy->idx == 0)
 153                 return IRQ_HANDLED;     /* wrong MSB -- ignore this byte */
 154
 155         if (twidjoy->idx < TWIDJOY_MAX_LENGTH)
 156                 twidjoy->data[twidjoy->idx++] = data;
 157
 158         if (twidjoy->idx == TWIDJOY_MAX_LENGTH) {
 159                 twidjoy_process_packet(twidjoy);
 160                 twidjoy->idx = 0;
 161         }
 162
 163         return IRQ_HANDLED;
 164 }
 165
 166 /*
 167  * twidjoy_disconnect() is the opposite of twidjoy_connect()
 168  */
 169
 170 static void twidjoy_disconnect(struct serio *serio)
 171 {
 172         struct twidjoy *twidjoy = serio_get_drvdata(serio);
 173
 174         serio_close(serio);
 175         serio_set_drvdata(serio, NULL);
 176         input_unregister_device(twidjoy->dev);
 177         kfree(twidjoy);
 178 }
 179
 180 /*
 181  * twidjoy_connect() is the routine that is called when someone adds a
 182  * new serio device. It looks for the Twiddler, and if found, registers
 183  * it as an input device.
 184  */
 185
 186 static int twidjoy_connect(struct serio *serio, struct serio_driver *drv)
 187 {
 188         struct twidjoy_button_spec *bp;
 189         struct twidjoy *twidjoy;
 190         struct input_dev *input_dev;
 191         int err = -ENOMEM;
 192         int i;
 193
 194         twidjoy = kzalloc(sizeof(struct twidjoy), GFP_KERNEL);
 195         input_dev = input_allocate_device();
 196         if (!twidjoy || !input_dev)
 197                 goto fail1;
 198
 199         twidjoy->dev = input_dev;
 200         snprintf(twidjoy->phys, sizeof(twidjoy->phys), "%s/input0", serio->phys);
 201
 202         input_dev->name = "Handykey Twiddler";
 203         input_dev->phys = twidjoy->phys;
 204         input_dev->id.bustype = BUS_RS232;
 205         input_dev->id.vendor = SERIO_TWIDJOY;
 206         input_dev->id.product = 0x0001;
 207         input_dev->id.version = 0x0100;
 208         input_dev->cdev.dev = &serio->dev;
 209         input_dev->private = twidjoy;
 210
 211         input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
 212         input_dev->absbit[0] = BIT(ABS_X) | BIT(ABS_Y);
 213         input_set_abs_params(input_dev, ABS_X, -50, 50, 4, 4);
 214         input_set_abs_params(input_dev, ABS_Y, -50, 50, 4, 4);
 215
 216         for (bp = twidjoy_buttons; bp->bitmask; bp++)
 217                 for (i = 0; i < bp->bitmask; i++)
 218                         set_bit(bp->buttons[i], input_dev->keybit);
 219
 220         serio_set_drvdata(serio, twidjoy);
 221
 222         err = serio_open(serio, drv);
 223         if (err)
 224                 goto fail2;
 225
 226         err = input_register_device(twidjoy->dev);
 227         if (err)
 228                 goto fail3;
 229
 230         return 0;
 231
 232  fail3: serio_close(serio);
 233  fail2: serio_set_drvdata(serio, NULL);
 234  fail1: input_free_device(input_dev);
 235         kfree(twidjoy);
 236         return err;
 237 }
 238
 239 /*
 240  * The serio driver structure.
 241  */
 242
 243 static struct serio_device_id twidjoy_serio_ids[] = {
 244         {
 245                 .type   = SERIO_RS232,
 246                 .proto  = SERIO_TWIDJOY,
 247                 .id     = SERIO_ANY,
 248                 .extra  = SERIO_ANY,
 249         },
 250         { 0 }
 251 };
 252
 253 MODULE_DEVICE_TABLE(serio, twidjoy_serio_ids);
 254
 255 static struct serio_driver twidjoy_drv = {
 256         .driver         = {
 257                 .name   = "twidjoy",
 258         },
 259         .description    = DRIVER_DESC,
 260         .id_table       = twidjoy_serio_ids,
 261         .interrupt      = twidjoy_interrupt,
 262         .connect        = twidjoy_connect,
 263         .disconnect     = twidjoy_disconnect,
 264 };
 265
 266 /*
 267  * The functions for inserting/removing us as a module.
 268  */
 269
 270 static int __init twidjoy_init(void)
 271 {
 272         return serio_register_driver(&twidjoy_drv);
 273 }
 274
 275 static void __exit twidjoy_exit(void)
 276 {
 277         serio_unregister_driver(&twidjoy_drv);
 278 }
 279
 280 module_init(twidjoy_init);
 281 module_exit(twidjoy_exit);