LUFA/Drivers/USB/Class/Device/CDC.h

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2010.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6            www.lufa-lib.org
   7 */
   8
   9 /*
  10   Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, distribute, and sell this
  13   software and its documentation for any purpose is hereby granted
  14   without fee, provided that the above copyright notice appear in
  15   all 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 /** \file
  32  *  \brief Device mode driver for the library USB CDC Class driver.
  33  *
  34  *  Device mode driver for the library USB CDC Class driver.
  35  *
  36  *  \note This file should not be included directly. It is automatically included as needed by the USB module driver
  37  *        dispatch header located in LUFA/Drivers/USB.h.
  38  */
  39
  40 /** \ingroup Group_USBClassCDC
  41  *  @defgroup Group_USBClassCDCDevice CDC Class Device Mode Driver
  42  *
  43  *  \section Sec_Dependencies Module Source Dependencies
  44  *  The following files must be built with any user project that uses this module:
  45  *    - LUFA/Drivers/USB/Class/Device/CDC.c <i>(Makefile source module name: LUFA_SRC_USBCLASS)</i>
  46  *
  47  *  \section Sec_ModDescription Module Description
  48  *  Device Mode USB Class driver framework interface, for the CDC USB Class driver.
  49  *
  50  *  \note There are several major drawbacks to the CDC-ACM standard USB class, however
  51  *        it is very standardized and thus usually available as a built-in driver on
  52  *        most platforms, and so is a better choice than a proprietary serial class.
  53  *
  54  *        One major issue with CDC-ACM is that it requires two Interface descriptors,
  55  *        which will upset most hosts when part of a multi-function "Composite" USB
  56  *        device, as each interface will be loaded into a separate driver instance. To
  57  *        combat this, you should use the "Interface Association Descriptor" addendum to
  58  *        the USB standard which is available on most OSes when creating Composite devices.
  59  *
  60  *        Another major oversight is that there is no mechanism for the host to notify the
  61  *        device that there is a data sink on the host side ready to accept data. This
  62  *        means that the device may try to send data while the host isn't listening, causing
  63  *        lengthy blocking timeouts in the transmission routines. To combat this, it is
  64  *        recommended that the virtual serial line DTR (Data Terminal Ready) be used where
  65  *        possible to determine if a host application is ready for data.
  66  *
  67  *  @{
  68  */
  69
  70 #ifndef _CDC_CLASS_DEVICE_H_
  71 #define _CDC_CLASS_DEVICE_H_
  72
  73         /* Includes: */
  74                 #include "../../USB.h"
  75                 #include "../Common/CDC.h"
  76
  77                 #include <stdio.h>
  78                 #include <string.h>
  79
  80         /* Enable C linkage for C++ Compilers: */
  81                 #if defined(__cplusplus)
  82                         extern "C" {
  83                 #endif
  84
  85         /* Preprocessor Checks: */
  86                 #if !defined(__INCLUDE_FROM_CDC_DRIVER)
  87                         #error Do not include this file directly. Include LUFA/Drivers/USB.h instead.
  88                 #endif
  89
  90                 #if defined(__INCLUDE_FROM_CDC_DEVICE_C) && defined(NO_STREAM_CALLBACKS)
  91                         #error The NO_STREAM_CALLBACKS compile time option cannot be used in projects using the library Class drivers.
  92                 #endif
  93
  94         /* Public Interface - May be used in end-application: */
  95                 /* Type Defines: */
  96                         /** \brief CDC Class Device Mode Configuration and State Structure.
  97                          *
  98                          *  Class state structure. An instance of this structure should be made for each CDC interface
  99                          *  within the user application, and passed to each of the CDC class driver functions as the
 100                          *  CDCInterfaceInfo parameter. This stores each CDC interface's configuration and state information.
 101                          */
 102                         typedef struct
 103                         {
 104                                 const struct
 105                                 {
 106                                         uint8_t  ControlInterfaceNumber; /**< Interface number of the CDC control interface within the device. */
 107
 108                                         uint8_t  DataINEndpointNumber; /**< Endpoint number of the CDC interface's IN data endpoint. */
 109                                         uint16_t DataINEndpointSize; /**< Size in bytes of the CDC interface's IN data endpoint. */
 110                                         bool     DataINEndpointDoubleBank; /**< Indicates if the CDC interface's IN data endpoint should use double banking. */
 111
 112                                         uint8_t  DataOUTEndpointNumber; /**< Endpoint number of the CDC interface's OUT data endpoint. */
 113                                         uint16_t DataOUTEndpointSize;  /**< Size in bytes of the CDC interface's OUT data endpoint. */
 114                                         bool     DataOUTEndpointDoubleBank; /**< Indicates if the CDC interface's OUT data endpoint should use double banking. */
 115
 116                                         uint8_t  NotificationEndpointNumber; /**< Endpoint number of the CDC interface's IN notification endpoint, if used. */
 117                                         uint16_t NotificationEndpointSize;  /**< Size in bytes of the CDC interface's IN notification endpoint, if used. */
 118                                         bool     NotificationEndpointDoubleBank; /**< Indicates if the CDC interface's notification endpoint should use double banking. */
 119                                 } Config; /**< Config data for the USB class interface within the device. All elements in this section
 120                                            *   <b>must</b> be set or the interface will fail to enumerate and operate correctly.
 121                                            */
 122                                 struct
 123                                 {
 124                                         struct
 125                                         {
 126                                                 uint8_t HostToDevice; /**< Control line states from the host to device, as a set of CDC_CONTROL_LINE_OUT_*
 127                                                                                            *   masks. This value is updated each time \ref CDC_Device_USBTask() is called.
 128                                                                                            */
 129                                                 uint8_t DeviceToHost; /**< Control line states from the device to host, as a set of CDC_CONTROL_LINE_IN_*
 130                                                                                            *   masks - to notify the host of changes to these values, call the
 131                                                                                            *   \ref CDC_Device_SendControlLineStateChange() function.
 132                                                                                            */
 133                                         } ControlLineStates; /**< Current states of the virtual serial port's control lines between the device and host. */
 134
 135                                         CDC_LineEncoding_t LineEncoding; /** Line encoding used in the virtual serial port, for the device's information.
 136                                                                           *  This is generally only used if the virtual serial port data is to be
 137                                                                           *  reconstructed on a physical UART.
 138                                                                           */
 139                                 } State; /**< State data for the USB class interface within the device. All elements in this section
 140                                           *   are reset to their defaults when the interface is enumerated.
 141                                           */
 142                         } USB_ClassInfo_CDC_Device_t;
 143
 144                 /* Function Prototypes: */
 145                         /** Configures the endpoints of a given CDC interface, ready for use. This should be linked to the library
 146                          *  \ref EVENT_USB_Device_ConfigurationChanged() event so that the endpoints are configured when the configuration containing
 147                          *  the given CDC interface is selected.
 148                          *
 149                          *  \note The endpoint index numbers as given in the interface's configuration structure must not overlap with any other
 150                          *        interface, or endpoint bank corruption will occur. Gaps in the allocated endpoint numbers or non-sequential indexes
 151                          *        within a single interface is allowed, but no two interfaces of any type have have interleaved endpoint indexes.
 152                          *
 153                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 154                          *
 155                          *  \return Boolean true if the endpoints were successfully configured, false otherwise.
 156                          */
 157                         bool CDC_Device_ConfigureEndpoints(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 158
 159                         /** Processes incoming control requests from the host, that are directed to the given CDC class interface. This should be
 160                          *  linked to the library \ref EVENT_USB_Device_ControlRequest() event.
 161                          *
 162                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 163                          */
 164                         void CDC_Device_ProcessControlRequest(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 165
 166                         /** General management task for a given CDC class interface, required for the correct operation of the interface. This should
 167                          *  be called frequently in the main program loop, before the master USB management task \ref USB_USBTask().
 168                          *
 169                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 170                          */
 171                         void CDC_Device_USBTask(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 172
 173                         /** CDC class driver event for a line encoding change on a CDC interface. This event fires each time the host requests a
 174                          *  line encoding change (containing the serial parity, baud and other configuration information) and may be hooked in the
 175                          *  user program by declaring a handler function with the same name and parameters listed here. The new line encoding
 176                          *  settings are available in the LineEncoding structure inside the CDC interface structure passed as a parameter.
 177                          *
 178                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 179                          */
 180                         void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 181
 182                         /** CDC class driver event for a control line state change on a CDC interface. This event fires each time the host requests a
 183                          *  control line state change (containing the virtual serial control line states, such as DTR) and may be hooked in the
 184                          *  user program by declaring a handler function with the same name and parameters listed here. The new control line states
 185                          *  are available in the ControlLineStates.HostToDevice value inside the CDC interface structure passed as a parameter, set as
 186                          *  a mask of CDC_CONTROL_LINE_OUT_* masks.
 187                          *
 188                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 189                          */
 190                         void EVENT_CDC_Device_ControLineStateChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 191
 192                         /** CDC class driver event for a send break request sent to the device from the host. This is generally used to separate
 193                          *  data or to indicate a special condition to the receiving device.
 194                          *
 195                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 196                          *  \param[in]     Duration          Duration of the break that has been sent by the host, in milliseconds.
 197                          */
 198                         void EVENT_CDC_Device_BreakSent(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo,
 199                                                         const uint8_t Duration) ATTR_NON_NULL_PTR_ARG(1);
 200
 201                         /** Sends a given string to the attached USB host, if connected. If a host is not connected when the function is called, the
 202                          *  string is discarded. Bytes will be queued for transmission to the host until either the endpoint bank becomes full, or the
 203                          *  \ref CDC_Device_Flush() function is called to flush the pending data to the host. This allows for multiple bytes to be
 204                          *  packed into a single endpoint packet, increasing data throughput.
 205                          *
 206                          *  \pre This function must only be called when the Device state machine is in the \ref DEVICE_STATE_Configured state or
 207                          *       the call will fail.
 208                          *
 209                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 210                          *  \param[in]     Data              Pointer to the string to send to the host.
 211                          *  \param[in]     Length            Size in bytes of the string to send to the host.
 212                          *
 213                          *  \return A value from the \ref Endpoint_Stream_RW_ErrorCodes_t enum.
 214                          */
 215                         uint8_t CDC_Device_SendString(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo,
 216                                                       const char* const Data,
 217                                                       const uint16_t Length) ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2);
 218
 219                         /** Sends a given byte to the attached USB host, if connected. If a host is not connected when the function is called, the
 220                          *  byte is discarded. Bytes will be queued for transmission to the host until either the endpoint bank becomes full, or the
 221                          *  \ref CDC_Device_Flush() function is called to flush the pending data to the host. This allows for multiple bytes to be
 222                          *  packed into a single endpoint packet, increasing data throughput.
 223                          *
 224                          *  \pre This function must only be called when the Device state machine is in the \ref DEVICE_STATE_Configured state or
 225                          *       the call will fail.
 226                          *
 227                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 228                          *  \param[in]     Data              Byte of data to send to the host.
 229                          *
 230                          *  \return A value from the \ref Endpoint_WaitUntilReady_ErrorCodes_t enum.
 231                          */
 232                         uint8_t CDC_Device_SendByte(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo,
 233                                                     const uint8_t Data) ATTR_NON_NULL_PTR_ARG(1);
 234
 235                         /** Determines the number of bytes received by the CDC interface from the host, waiting to be read. This indicates the number
 236                          *  of bytes in the OUT endpoint bank only, and thus the number of calls to \ref CDC_Device_ReceiveByte() which are guaranteed to
 237                          *  succeed immediately. If multiple bytes are to be received, they should be buffered by the user application, as the endpoint
 238                          *  bank will not be released back to the USB controller until all bytes are read.
 239                          *
 240                          *  \pre This function must only be called when the Device state machine is in the \ref DEVICE_STATE_Configured state or
 241                          *       the call will fail.
 242                          *
 243                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 244                          *
 245                          *  \return Total number of buffered bytes received from the host.
 246                          */
 247                         uint16_t CDC_Device_BytesReceived(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 248
 249                         /** Reads a byte of data from the host. If no data is waiting to be read of if a USB host is not connected, the function
 250                          *  returns a negative value. The \ref CDC_Device_BytesReceived() function may be queried in advance to determine how many
 251                          *  bytes are currently buffered in the CDC interface's data receive endpoint bank, and thus how many repeated calls to this
 252                          *  function which are guaranteed to succeed.
 253                          *
 254                          *  \pre This function must only be called when the Device state machine is in the \ref DEVICE_STATE_Configured state or
 255                          *       the call will fail.
 256                          *
 257                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 258                          *
 259                          *  \return Next received byte from the host, or a negative value if no data received.
 260                          */
 261                         int16_t CDC_Device_ReceiveByte(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 262
 263                         /** Flushes any data waiting to be sent, ensuring that the send buffer is cleared.
 264                          *
 265                          *  \pre This function must only be called when the Device state machine is in the \ref DEVICE_STATE_Configured state or
 266                          *       the call will fail.
 267                          *
 268                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 269                          *
 270                          *  \return A value from the \ref Endpoint_WaitUntilReady_ErrorCodes_t enum.
 271                          */
 272                         uint8_t CDC_Device_Flush(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 273
 274                         /** Sends a Serial Control Line State Change notification to the host. This should be called when the virtual serial
 275                          *  control lines (DCD, DSR, etc.) have changed states, or to give BREAK notifications to the host. Line states persist
 276                          *  until they are cleared via a second notification. This should be called each time the CDC class driver's
 277                          *  ControlLineStates.DeviceToHost value is updated to push the new states to the USB host.
 278                          *
 279                          *  \pre This function must only be called when the Device state machine is in the \ref DEVICE_STATE_Configured state or
 280                          *       the call will fail.
 281                          *
 282                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 283                          */
 284                         void CDC_Device_SendControlLineStateChange(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 285
 286                         /** Creates a standard character stream for the given CDC Device instance so that it can be used with all the regular
 287                          *  functions in the avr-libc <stdio.h> library that accept a FILE stream as a destination (e.g. fprintf). The created
 288                          *  stream is bidirectional and can be used for both input and output functions.
 289                          *
 290                          *  Reading data from this stream is non-blocking, i.e. in most instances, complete strings cannot be read in by a single
 291                          *  fetch, as the endpoint will not be ready at some point in the transmission, aborting the transfer. However, this may
 292                          *  be used when the read data is processed byte-per-bye (via getc()) or when the user application will implement its own
 293                          *  line buffering.
 294                          *
 295                          *  \note The created stream can be given as stdout if desired to direct the standard output from all <stdio.h> functions
 296                          *        to the given CDC interface.
 297                          *
 298                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 299                          *  \param[in,out] Stream            Pointer to a FILE structure where the created stream should be placed.
 300                          */
 301                         void CDC_Device_CreateStream(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo,
 302                                                      FILE* const Stream) ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2);
 303
 304                         /** Identical to CDC_Device_CreateStream(), except that reads are blocking until the calling stream function terminates
 305                          *  the transfer. While blocking, the USB and CDC service tasks are called repeatedly to maintain USB communications.
 306                          *
 307                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 308                          *  \param[in,out] Stream            Pointer to a FILE structure where the created stream should be placed.
 309                          */
 310                         void CDC_Device_CreateBlockingStream(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo,
 311                                                              FILE* const Stream) ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2);
 312
 313         /* Private Interface - For use in library only: */
 314         #if !defined(__DOXYGEN__)
 315                 /* Function Prototypes: */
 316                         #if defined(__INCLUDE_FROM_CDC_DEVICE_C)
 317                                 static int CDC_Device_putchar(char c,
 318                                                               FILE* Stream) ATTR_NON_NULL_PTR_ARG(2);
 319                                 static int CDC_Device_getchar(FILE* Stream) ATTR_NON_NULL_PTR_ARG(1);
 320                                 static int CDC_Device_getchar_Blocking(FILE* Stream) ATTR_NON_NULL_PTR_ARG(1);
 321
 322                                 void CDC_Device_Event_Stub(void);
 323                                 void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 324                                                                           ATTR_WEAK ATTR_NON_NULL_PTR_ARG(1) ATTR_ALIAS(CDC_Device_Event_Stub);
 325                                 void EVENT_CDC_Device_ControLineStateChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 326                                                                              ATTR_WEAK ATTR_NON_NULL_PTR_ARG(1) ATTR_ALIAS(CDC_Device_Event_Stub);
 327                                 void EVENT_CDC_Device_BreakSent(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo,
 328                                                                 const uint8_t Duration) ATTR_WEAK ATTR_NON_NULL_PTR_ARG(1)
 329                                                                 ATTR_ALIAS(CDC_Device_Event_Stub);
 330                         #endif
 331
 332         #endif
 333
 334         /* Disable C linkage for C++ Compilers: */
 335                 #if defined(__cplusplus)
 336                         }
 337                 #endif
 338
 339 #endif
 340
 341 /** @} */
 342