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