|
|
/****************************************************************************
* include/nuttx/input/djoystick.h
*
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/* This header file provides definition for a standard discrete joystick
* interface. A discrete joystick refers to a joystick that could be
* implemented entirely with GPIO input pins. So up, down, left, and right
* are all discrete values like buttons (as opposed to integer values like
* you might obtain from an analog joystick).
*
* The discrete joystick driver exports a standard character driver
* interface. By convention, the discrete joystick is registered as an input
* device at /dev/djoyN where N uniquely identifies the driver instance.
*
* This header file documents the generic interface that all NuttX discrete
* joystick devices must conform. It adds standards and conventions on top
* of the standard character driver interface.
*/
#ifndef __INCLUDE_NUTTX_INPUT_DJOYSTICK_H
#define __INCLUDE_NUTTX_INPUT_DJOYSTICK_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/fs/ioctl.h>
/****************************************************************************
* Pre-Processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
#ifndef CONFIG_DJOYSTICK_NPOLLWAITERS
# define CONFIG_DJOYSTICK_NPOLLWAITERS 2
#endif
/* Joystick Interface *******************************************************/
/* These definitions provide the meaning of all of the bits that may be
* reported in the djoy_buttonset_t bitset.
*/
#define DJOY_UP (0) /* Bit 0: Joystick UP */
#define DJOY_DOWN (1) /* Bit 1: Joystick DOWN */
#define DJOY_LEFT (2) /* Bit 2: Joystick LEFT */
#define DJOY_RIGHT (3) /* Bit 3: Joystick RIGHT */
#define DJOY_BUTTON_1 (4) /* Bit 4: Button 1 */
#define DJOY_BUTTON_2 (5) /* Bit 5: Button 2 */
#define DJOY_BUTTON_3 (6) /* Bit 6: Button 3 */
#define DJOY_BUTTON_4 (7) /* Bit 7: Button 4 */
#define DJOY_NDISCRETES (8) /* Total number of discrete signals */
#define DJOY_UP_BIT (1 << DJOY_UP) /* 1:Joystick UP selected */
#define DJOY_DOWN_BIT (1 << DJOY_DOWN) /* 1:Joystick DOWN selected */
#define DJOY_LEFT_BIT (1 << DJOY_LEFT) /* 1:Joystick LEFT selected */
#define DJOY_RIGHT_BIT (1 << DJOY_RIGHT) /* 1:Joystick RIGHT selected */
#define DJOY_BUTTONS_JOYBITS 0x0f /* Set of all joystick directions */
#define DJOY_BUTTON_1_BIT (1 << DJOY_BUTTON_1) /* 1:Button 1 pressed */
#define DJOY_BUTTON_2_BIT (1 << DJOY_BUTTON_2) /* 1:Button 2 pressed */
#define DJOY_BUTTON_3_BIT (1 << DJOY_BUTTON_3) /* 1:Button 3 pressed */
#define DJOY_BUTTON_4_BIT (1 << DJOY_BUTTON_4) /* 1:Button 4 pressed */
#define DJOY_BUTTONS_ALLBITS 0xf0 /* Set of all buttons */
#define DJOY_ALLBITS 0xff /* Set of all bits */
/* Typical usage */
#define DJOY_BUTTON_SELECT DJOY_BUTTON_1
#define DJOY_BUTTON_FIRE DJOY_BUTTON_2
#define DJOY_BUTTON_JUMP DJOY_BUTTON_3
#define DJOY_BUTTON_RUN DJOY_BUTTON_4
#define DJOY_BUTTON_SELECT_BIT DJOY_BUTTON_1_BIT
#define DJOY_BUTTON_FIRE_BIT DJOY_BUTTON_2_BIT
#define DJOY_BUTTON_JUMP_BIT DJOY_BUTTON_3_BIT
#define DJOY_BUTTON_RUN_BIT DJOY_BUTTON_4_BIT
/* IOCTL commands
*
* Discrete joystick drivers do not support the character driver write() or
* seek() methods. The remaining driver methods behave as follows:
*
* 1) The read() method will always return a single value of size
* djoy_buttonset_t represent the current state of the joystick buttons.
* read() never blocks.
* 2) The poll() method can be used to notify a client if there is a change
* in any of the joystick discrete inputs. This feature, of course,
* depends upon interrupt GPIO support from the platform. NOTE: that
* semantics of poll() for POLLIN are atypical: The successful poll
* means that the data has changed and has nothing to with the
* availability of data to be read; data is always available to be
* read.
* 3) The ioctl() method supports the commands documented below:
*/
/* Command: DJOYIOC_SUPPORTED
* Description: Report the set of button events supported by the hardware;
* Argument: A pointer to writeable integer value in which to return the
* set of supported buttons.
* Return: Zero (OK) on success. Minus one will be returned on failure
* with the errno value set appropriately.
*/
#define DJOYIOC_SUPPORTED _DJOYIOC(0x0001)
/* Command: DJOYIOC_POLLEVENTS
* Description: Specify the set of button events that can cause a poll()
* to awaken. The default is all button depressions and all
* button releases (all supported buttons);
* Argument: A read-only pointer to an instance of struct djoy_pollevents_s
* Return: Zero (OK) on success. Minus one will be returned on failure
* with the errno value set appropriately.
*/
#define DJOYIOC_POLLEVENTS _DJOYIOC(0x0002)
/* Command: DJOYIOC_REGISTER
* Description: Register to receive a signal whenever there is a change in
* any of the joystick discrete inputs. This feature, of
* course, depends upon interrupt GPIO support from the
* platform.
* Argument: A read-only pointer to an instance of struct djoy_notify_s
* Return: Zero (OK) on success. Minus one will be returned on failure
* with the errno value set appropriately.
*/
#define DJOYIOC_REGISTER _DJOYIOC(0x0003)
/****************************************************************************
* Public Types
****************************************************************************/
/* This type is a bit set that contains the state of all discrete joystick
* buttons.
*/
typedef uint8_t djoy_buttonset_t;
/* A reference to this structure is provided with the DJOYIOC_POLLEVENTS IOCTL
* command and describes the conditions under which the client would like
* to receive notification.
*/
struct djoy_pollevents_s
{
djoy_buttonset_t dp_press; /* Set of button depressions to wake up the poll */
djoy_buttonset_t dp_release; /* Set of button releases to wake up the poll */
};
/* A reference to this structure is provided with the DJOYIOC_REGISTER IOCTL
* command and describes the conditions under which the client would like
* to receive notification.
*/
struct djoy_notify_s
{
djoy_buttonset_t dn_press; /* Set of button depressions to be notified */
djoy_buttonset_t dn_release; /* Set of button releases to be notified */
uint8_t dn_signo; /* Signal number to use in the notification */
};
/* This is the type of the discrete joystick interrupt handler used with
* the struct djoy_lowerhalf_s enable() method.
*/
struct djoy_lowerhalf_s;
typedef CODE void (*djoy_interrupt_t)
(FAR const struct djoy_lowerhalf_s *lower, FAR void *arg);
/* The discrete joystick driver is a two-part driver:
*
* 1) A common upper half driver that provides the common user interface to
* the joystick,
* 2) Platform-specific lower half drivers that provide the interface
* between the common upper half and the platform discrete inputs.
*
* This structure defines the interface between an instance of the lower
* half driver and the common upper half driver. Such an instance is
* passed to the upper half driver when the driver is initialized, binding
* the upper and lower halves into one driver.
*/
struct djoy_lowerhalf_s
{
/* Return the set of buttons supported on the discrete joystick device */
CODE djoy_buttonset_t (*dl_supported)(FAR const struct djoy_lowerhalf_s *lower);
/* Return the current state of all discrete joystick buttons */
CODE djoy_buttonset_t (*dl_sample)(FAR const struct djoy_lowerhalf_s *lower);
/* Enable interrupts on the selected set of joystick buttons. And empty
* set will disable all interrupts.
*/
CODE void (*dl_enable)(FAR const struct djoy_lowerhalf_s *lower,
djoy_buttonset_t press, djoy_buttonset_t release,
djoy_interrupt_t handler, FAR void *arg);
};
/****************************************************************************
* Public Data
****************************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/****************************************************************************
* Name: djoy_register
*
* Description:
* Bind the lower half discrete joystick driver to an instance of the
* upper half discrete joystick driver and register the composite character
* driver as the specified device.
*
* Input Parameters:
* devname - The name of the discrete joystick device to be registers.
* This should be a string of the form "/dev/djoyN" where N is the the
* minor device number.
* lower - An instance of the platform-specific discrete joystick lower
* half driver.
*
* Returned Values:
* Zero (OK) is returned on success. Otherwise a negated errno value is
* returned to indicate the nature of the failure.
*
****************************************************************************/
int djoy_register(FAR const char *devname,
FAR const struct djoy_lowerhalf_s *lower);
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* __INCLUDE_NUTTX_INPUT_DJOYSTICK_H */
|
