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Release 4.14 drivers/input/joystick/twidjoy.c

/*
 *  Copyright (c) 2001 Arndt Schoenewald
 *  Copyright (c) 2000-2001 Vojtech Pavlik
 *  Copyright (c) 2000 Mark Fletcher
 *
 *  Sponsored by Quelltext AG (http://www.quelltext-ag.de), Dortmund, Germany
 */

/*
 * Driver to use Handykey's Twiddler (the first edition, i.e. the one with
 * the RS232 interface) as a joystick under Linux
 *
 * The Twiddler is a one-handed chording keyboard featuring twelve buttons on
 * the front, six buttons on the top, and a built-in tilt sensor. The buttons
 * on the front, which are grouped as four rows of three buttons, are pressed
 * by the four fingers (this implies only one button per row can be held down
 * at the same time) and the buttons on the top are for the thumb. The tilt
 * sensor delivers X and Y axis data depending on how the Twiddler is held.
 * Additional information can be found at http://www.handykey.com.
 *
 * This driver does not use the Twiddler for its intended purpose, i.e. as
 * a chording keyboard, but as a joystick: pressing and releasing a button
 * immediately sends a corresponding button event, and tilting it generates
 * corresponding ABS_X and ABS_Y events. This turns the Twiddler into a game
 * controller with amazing 18 buttons :-)
 *
 * Note: The Twiddler2 (the successor of the Twiddler that connects directly
 * to the PS/2 keyboard and mouse ports) is NOT supported by this driver!
 *
 * For questions or feedback regarding this driver module please contact:
 * Arndt Schoenewald <arndt@quelltext.com>
 */

/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/serio.h>


#define DRIVER_DESC	"Handykey Twiddler keyboard as a joystick driver"


MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

/*
 * Constants.
 */


#define TWIDJOY_MAX_LENGTH 5


static struct twidjoy_button_spec {
	
int bitshift;
	
int bitmask;
	
int buttons[3];
}

twidjoy_buttons[] = {
	{  0, 3, { BTN_A,      BTN_B,     BTN_C    } },
	{  2, 3, { BTN_X,      BTN_Y,     BTN_Z    } },
	{  4, 3, { BTN_TL,     BTN_TR,    BTN_TR2  } },
	{  6, 3, { BTN_SELECT, BTN_START, BTN_MODE } },
	{  8, 1, { BTN_BASE5                       } },
	{  9, 1, { BTN_BASE                        } },
	{ 10, 1, { BTN_BASE3                       } },
	{ 11, 1, { BTN_BASE4                       } },
	{ 12, 1, { BTN_BASE2                       } },
	{ 13, 1, { BTN_BASE6                       } },
	{ 0,  0, { 0                               } }
};

/*
 * Per-Twiddler data.
 */


struct twidjoy {
	
struct input_dev *dev;
	
int idx;
	
unsigned char data[TWIDJOY_MAX_LENGTH];
	
char phys[32];
};

/*
 * twidjoy_process_packet() decodes packets the driver receives from the
 * Twiddler. It updates the data accordingly.
 */


static void twidjoy_process_packet(struct twidjoy *twidjoy) { struct input_dev *dev = twidjoy->dev; unsigned char *data = twidjoy->data; struct twidjoy_button_spec *bp; int button_bits, abs_x, abs_y; button_bits = ((data[1] & 0x7f) << 7) | (data[0] & 0x7f); for (bp = twidjoy_buttons; bp->bitmask; bp++) { int value = (button_bits & (bp->bitmask << bp->bitshift)) >> bp->bitshift; int i; for (i = 0; i < bp->bitmask; i++) input_report_key(dev, bp->buttons[i], i+1 == value); } abs_x = ((data[4] & 0x07) << 5) | ((data[3] & 0x7C) >> 2); if (data[4] & 0x08) abs_x -= 256; abs_y = ((data[3] & 0x01) << 7) | ((data[2] & 0x7F) >> 0); if (data[3] & 0x02) abs_y -= 256; input_report_abs(dev, ABS_X, -abs_x); input_report_abs(dev, ABS_Y, +abs_y); input_sync(dev); }

Contributors

PersonTokensPropCommitsCommitProp
Vojtech Pavlik244100.00%2100.00%
Total244100.00%2100.00%

/* * twidjoy_interrupt() is called by the low level driver when characters * are ready for us. We then buffer them for further processing, or call the * packet processing routine. */
static irqreturn_t twidjoy_interrupt(struct serio *serio, unsigned char data, unsigned int flags) { struct twidjoy *twidjoy = serio_get_drvdata(serio); /* All Twiddler packets are 5 bytes. The fact that the first byte * has a MSB of 0 and all other bytes have a MSB of 1 can be used * to check and regain sync. */ if ((data & 0x80) == 0) twidjoy->idx = 0; /* this byte starts a new packet */ else if (twidjoy->idx == 0) return IRQ_HANDLED; /* wrong MSB -- ignore this byte */ if (twidjoy->idx < TWIDJOY_MAX_LENGTH) twidjoy->data[twidjoy->idx++] = data; if (twidjoy->idx == TWIDJOY_MAX_LENGTH) { twidjoy_process_packet(twidjoy); twidjoy->idx = 0; } return IRQ_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
Vojtech Pavlik9490.38%133.33%
Dmitry Torokhov109.62%266.67%
Total104100.00%3100.00%

/* * twidjoy_disconnect() is the opposite of twidjoy_connect() */
static void twidjoy_disconnect(struct serio *serio) { struct twidjoy *twidjoy = serio_get_drvdata(serio); serio_close(serio); serio_set_drvdata(serio, NULL); input_unregister_device(twidjoy->dev); kfree(twidjoy); }

Contributors

PersonTokensPropCommitsCommitProp
Vojtech Pavlik2862.22%133.33%
Dmitry Torokhov1737.78%266.67%
Total45100.00%3100.00%

/* * twidjoy_connect() is the routine that is called when someone adds a * new serio device. It looks for the Twiddler, and if found, registers * it as an input device. */
static int twidjoy_connect(struct serio *serio, struct serio_driver *drv) { struct twidjoy_button_spec *bp; struct twidjoy *twidjoy; struct input_dev *input_dev; int err = -ENOMEM; int i; twidjoy = kzalloc(sizeof(struct twidjoy), GFP_KERNEL); input_dev = input_allocate_device(); if (!twidjoy || !input_dev) goto fail1; twidjoy->dev = input_dev; snprintf(twidjoy->phys, sizeof(twidjoy->phys), "%s/input0", serio->phys); input_dev->name = "Handykey Twiddler"; input_dev->phys = twidjoy->phys; input_dev->id.bustype = BUS_RS232; input_dev->id.vendor = SERIO_TWIDJOY; input_dev->id.product = 0x0001; input_dev->id.version = 0x0100; input_dev->dev.parent = &serio->dev; input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); input_set_abs_params(input_dev, ABS_X, -50, 50, 4, 4); input_set_abs_params(input_dev, ABS_Y, -50, 50, 4, 4); for (bp = twidjoy_buttons; bp->bitmask; bp++) for (i = 0; i < bp->bitmask; i++) set_bit(bp->buttons[i], input_dev->keybit); serio_set_drvdata(serio, twidjoy); err = serio_open(serio, drv); if (err) goto fail2; err = input_register_device(twidjoy->dev); if (err) goto fail3; return 0; fail3: serio_close(serio); fail2: serio_set_drvdata(serio, NULL); fail1: input_free_device(input_dev); kfree(twidjoy); return err; }

Contributors

PersonTokensPropCommitsCommitProp
Vojtech Pavlik15950.32%218.18%
Dmitry Torokhov15549.05%872.73%
Jiri Slaby20.63%19.09%
Total316100.00%11100.00%

/* * The serio driver structure. */ static const struct serio_device_id twidjoy_serio_ids[] = { { .type = SERIO_RS232, .proto = SERIO_TWIDJOY, .id = SERIO_ANY, .extra = SERIO_ANY, }, { 0 } }; MODULE_DEVICE_TABLE(serio, twidjoy_serio_ids); static struct serio_driver twidjoy_drv = { .driver = { .name = "twidjoy", }, .description = DRIVER_DESC, .id_table = twidjoy_serio_ids, .interrupt = twidjoy_interrupt, .connect = twidjoy_connect, .disconnect = twidjoy_disconnect, }; module_serio_driver(twidjoy_drv);

Overall Contributors

PersonTokensPropCommitsCommitProp
Vojtech Pavlik74873.69%420.00%
Dmitry Torokhov26125.71%1260.00%
Axel Lin20.20%15.00%
Jiri Slaby20.20%15.00%
Arvind Yadav10.10%15.00%
Adrian Bunk10.10%15.00%
Total1015100.00%20100.00%
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