LUFA/Drivers/USB/HighLevel/USBTask.h

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2009.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2009  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, and distribute this software
  13   and its documentation for any purpose and without fee is hereby
  14   granted, provided that the above copyright notice appear in all
  15   copies and that both that the copyright notice and this
  16   permission notice and warranty disclaimer appear in supporting
  17   documentation, and that the name of the author not be used in
  18   advertising or publicity pertaining to distribution of the
  19   software without specific, written prior permission.
  20
  21   The author disclaim all warranties with regard to this
  22   software, including all implied warranties of merchantability
  23   and fitness.  In no event shall the author be liable for any
  24   special, indirect or consequential damages or any damages
  25   whatsoever resulting from loss of use, data or profits, whether
  26   in an action of contract, negligence or other tortious action,
  27   arising out of or in connection with the use or performance of
  28   this software.
  29 */
  30
  31 #ifndef __USBTASK_H__
  32 #define __USBTASK_H__
  33
  34         /* Includes: */
  35                 #include <avr/io.h>
  36                 #include <avr/interrupt.h>
  37                 #include <util/atomic.h>
  38                 #include <stdbool.h>
  39                 #include <stddef.h>
  40
  41                 #include "../LowLevel/LowLevel.h"
  42                 #include "StdRequestType.h"
  43                 #include "USBMode.h"
  44                 #include "Events.h"
  45                 #include "StdDescriptors.h"
  46
  47                 #if defined(USB_CAN_BE_HOST)
  48                         #include "../LowLevel/HostChapter9.h"
  49                 #endif
  50
  51         /* Enable C linkage for C++ Compilers: */
  52                 #if defined(__cplusplus)
  53                         extern "C" {
  54                 #endif
  55
  56         /* Public Interface - May be used in end-application: */
  57                 /* Global Variables: */
  58                         /** Indicates if the USB interface is currently initialized but not necessarily connected to a host
  59                          *  or device (i.e. if \ref USB_Init() has been run). If this is false, all other library globals are invalid.
  60                          *
  61                          *  \note This variable should be treated as read-only in the user application, and never manually
  62                          *        changed in value.
  63                          *
  64                          *  \ingroup Group_USBManagement
  65                          */
  66                         extern volatile bool USB_IsInitialized;
  67
  68                         /** Structure containing the last received Control request when in Device mode (for use in user-applications
  69                          *  inside of the \ref EVENT_USB_UnhandledControlPacket() event, or for filling up with a control request to issue when
  70                          *  in Host mode before calling \ref USB_Host_SendControlRequest().
  71                          *
  72                          *  \ingroup Group_USBManagement
  73                          */
  74                          extern USB_Request_Header_t USB_ControlRequest;
  75
  76                         #if defined(USB_CAN_BE_HOST) || defined(__DOXYGEN__)
  77                         /** Indicates the current host state machine state. When in host mode, this indicates the state
  78                          *  via one of the values of the \ref USB_Host_States_t enum values.
  79                          *
  80                          *  This value may be altered by the user application to implement the \ref HOST_STATE_Addressed,
  81                          *  \ref HOST_STATE_Configured and \ref HOST_STATE_Suspended states which are not implemented by
  82                          *  the library.
  83                          *
  84                          *  \note This global is only present if the user application can be a USB host.
  85                          *
  86                          *  \see \ref USB_Host_States_t for a list of possible device states
  87                          *
  88                          *  \ingroup Group_Host
  89                          */
  90                         extern volatile uint8_t USB_HostState;
  91                         #endif
  92
  93                         #if defined(USB_CAN_BE_DEVICE) || defined(__DOXYGEN__)
  94                         /** Indicates the current device state machine state. When in device mode, this indicates the state
  95                          *  via one of the values of the \ref USB_Device_States_t enum values.
  96                          *
  97                          *  This value should not be altered by the user application as it is handled automatically by the
  98                          *  library. The only exception to this rule is if the NO_LIMITED_CONTROLLER_CONNECT token is used
  99                          *  (see \ref EVENT_USB_Connect() and \ref EVENT_USB_Disconnect() events).
 100                          *
 101                          *  \note This global is only present if the user application can be a USB device.
 102                          *
 103                          *  \note This variable should be treated as read-only in the user application, and never manually
 104                          *        changed in value except in the circumstances outlined above.
 105                          *
 106                          *  \see \ref USB_Device_States_t for a list of possible device states
 107                          *
 108                          *  \ingroup Group_Device
 109                          */
 110                         extern volatile uint8_t USB_DeviceState;
 111                         #endif
 112
 113                 /* Function Prototypes: */
 114                         /** This is the main USB management task. The USB driver requires that this task be executed
 115                          *  continuously when the USB system is active (device attached in host mode, or attached to a host
 116                          *  in device mode) in order to manage USB communications. This task may be executed inside an RTOS,
 117                          *  fast timer ISR or the main user application loop.
 118                          *
 119                          *  The USB task must be serviced within 30ms while in device mode, or within 1ms while in host mode.
 120                          *  The task may be serviced at all times, or (for minimum CPU consumption):
 121                          *
 122                          *    - In device mode, it may be disabled at start-up, enabled on the firing of the \ref EVENT_USB_Connect() event
 123                          *    and disabled again on the firing of the \ref EVENT_USB_Disconnect() event.
 124                          *
 125                          *    - In host mode, it may be disabled at start-up, enabled on the firing of the \ref EVENT_USB_DeviceAttached()
 126                          *    event and disabled again on the firing of the \ref EVENT_USB_DeviceEnumerationComplete() or
 127                          *    \ref EVENT_USB_DeviceEnumerationFailed() events.
 128                          *
 129                          *  If in device mode (only), the control endpoint can instead be managed via interrupts entirely by the library
 130                          *  by defining the INTERRUPT_CONTROL_ENDPOINT token and passing it to the compiler via the -D switch.
 131                          *
 132                          *  \see \ref Group_Events for more information on the USB events.
 133                          *
 134                          *  \ingroup Group_USBManagement
 135                          */
 136                         void USB_USBTask(void);
 137
 138         /* Private Interface - For use in library only: */
 139         #if !defined(__DOXYGEN__)
 140                 /* Function Prototypes: */
 141                         #if defined(INCLUDE_FROM_USBTASK_C)
 142                                 #if defined(USB_CAN_BE_HOST)
 143                                         static void USB_HostTask(void);
 144                                 #endif
 145
 146                                 #if defined(USB_CAN_BE_DEVICE)
 147                                         static void USB_DeviceTask(void);
 148                                 #endif
 149                         #endif
 150
 151                 /* Macros: */
 152                         #define HOST_TASK_NONBLOCK_WAIT(duration, nextstate) {USB_HostState = HOST_STATE_WaitForDevice; WaitMSRemaining = duration; PostWaitState = nextstate; }
 153         #endif
 154
 155         /* Disable C linkage for C++ Compilers: */
 156                 #if defined(__cplusplus)
 157                         }
 158                 #endif
 159
 160 #endif