uinput.h

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/*
 *  User level driver support for input subsystem
 *
 * Heavily based on evdev.c by Vojtech Pavlik
 *
 * 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
 *
 * Author: Aristeu Sergio Rozanski Filho <[email protected]>
 *
 * Changes/Revisions:
 *  0.3 24/05/2006 (Anssi Hannula <anssi.hannulagmail.com>)
 *      - update ff support for the changes in kernel interface
 *      - add UINPUT_VERSION
 *  0.2 16/10/2004 (Micah Dowty <[email protected]>)
 *      - added force feedback support
 *             - added UI_SET_PHYS
 *  0.1 20/06/2002
 *      - first public version
 */
#ifndef _UAPI__UINPUT_H_
#define _UAPI__UINPUT_H_

#include <linux/types.h>
#include <linux/input.h>

#define UINPUT_VERSION      3


struct uinput_ff_upload {
    __u32           request_id;
    __s32           retval;
    struct ff_effect    effect;
    struct ff_effect    old;
};

struct uinput_ff_erase {
    __u32           request_id;
    __s32           retval;
    __u32           effect_id;
};

/* ioctl */
#define UINPUT_IOCTL_BASE   'U'
#define UI_DEV_CREATE       _IO(UINPUT_IOCTL_BASE, 1)
#define UI_DEV_DESTROY      _IO(UINPUT_IOCTL_BASE, 2)

#define UI_SET_EVBIT        _IOW(UINPUT_IOCTL_BASE, 100, int)
#define UI_SET_KEYBIT       _IOW(UINPUT_IOCTL_BASE, 101, int)
#define UI_SET_RELBIT       _IOW(UINPUT_IOCTL_BASE, 102, int)
#define UI_SET_ABSBIT       _IOW(UINPUT_IOCTL_BASE, 103, int)
#define UI_SET_MSCBIT       _IOW(UINPUT_IOCTL_BASE, 104, int)
#define UI_SET_LEDBIT       _IOW(UINPUT_IOCTL_BASE, 105, int)
#define UI_SET_SNDBIT       _IOW(UINPUT_IOCTL_BASE, 106, int)
#define UI_SET_FFBIT        _IOW(UINPUT_IOCTL_BASE, 107, int)
#define UI_SET_PHYS     _IOW(UINPUT_IOCTL_BASE, 108, char*)
#define UI_SET_SWBIT        _IOW(UINPUT_IOCTL_BASE, 109, int)
#define UI_SET_PROPBIT      _IOW(UINPUT_IOCTL_BASE, 110, int)

#define UI_BEGIN_FF_UPLOAD  _IOWR(UINPUT_IOCTL_BASE, 200, struct uinput_ff_upload)
#define UI_END_FF_UPLOAD    _IOW(UINPUT_IOCTL_BASE, 201, struct uinput_ff_upload)
#define UI_BEGIN_FF_ERASE   _IOWR(UINPUT_IOCTL_BASE, 202, struct uinput_ff_erase)
#define UI_END_FF_ERASE     _IOW(UINPUT_IOCTL_BASE, 203, struct uinput_ff_erase)

/*
 * To write a force-feedback-capable driver, the upload_effect
 * and erase_effect callbacks in input_dev must be implemented.
 * The uinput driver will generate a fake input event when one of
 * these callbacks are invoked. The userspace code then uses
 * ioctls to retrieve additional parameters and send the return code.
 * The callback blocks until this return code is sent.
 *
 * The described callback mechanism is only used if ff_effects_max
 * is set.
 *
 * To implement upload_effect():
 *   1. Wait for an event with type == EV_UINPUT and code == UI_FF_UPLOAD.
 *      A request ID will be given in 'value'.
 *   2. Allocate a uinput_ff_upload struct, fill in request_id with
 *      the 'value' from the EV_UINPUT event.
 *   3. Issue a UI_BEGIN_FF_UPLOAD ioctl, giving it the
 *      uinput_ff_upload struct. It will be filled in with the
 *      ff_effects passed to upload_effect().
 *   4. Perform the effect upload, and place a return code back into
        the uinput_ff_upload struct.
 *   5. Issue a UI_END_FF_UPLOAD ioctl, also giving it the
 *      uinput_ff_upload_effect struct. This will complete execution
 *      of our upload_effect() handler.
 *
 * To implement erase_effect():
 *   1. Wait for an event with type == EV_UINPUT and code == UI_FF_ERASE.
 *      A request ID will be given in 'value'.
 *   2. Allocate a uinput_ff_erase struct, fill in request_id with
 *      the 'value' from the EV_UINPUT event.
 *   3. Issue a UI_BEGIN_FF_ERASE ioctl, giving it the
 *      uinput_ff_erase struct. It will be filled in with the
 *      effect ID passed to erase_effect().
 *   4. Perform the effect erasure, and place a return code back
 *      into the uinput_ff_erase struct.
 *   5. Issue a UI_END_FF_ERASE ioctl, also giving it the
 *      uinput_ff_erase_effect struct. This will complete execution
 *      of our erase_effect() handler.
 */

/*
 * This is the new event type, used only by uinput.
 * 'code' is UI_FF_UPLOAD or UI_FF_ERASE, and 'value'
 * is the unique request ID. This number was picked
 * arbitrarily, above EV_MAX (since the input system
 * never sees it) but in the range of a 16-bit int.
 */
#define EV_UINPUT       0x0101
#define UI_FF_UPLOAD        1
#define UI_FF_ERASE     2

#define UINPUT_MAX_NAME_SIZE    80
struct uinput_user_dev {
    char name[UINPUT_MAX_NAME_SIZE];
    struct input_id id;
    __u32 ff_effects_max;
    __s32 absmax[ABS_CNT];
    __s32 absmin[ABS_CNT];
    __s32 absfuzz[ABS_CNT];
    __s32 absflat[ABS_CNT];
};
#endif /* _UAPI__UINPUT_H_ */