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.fourwalledcubicle.com
   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 class driver
  37  *        dispatch header located in LUFA/Drivers/USB/Class/CDC.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 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/Class/CDC.h instead.
  88                 #endif
  89
  90         /* Public Interface - May be used in end-application: */
  91                 /* Type Defines: */
  92                         /** \brief CDC Class Device Mode Configuration and State Structure.
  93                          *
  94                          *  Class state structure. An instance of this structure should be made for each CDC interface
  95                          *  within the user application, and passed to each of the CDC class driver functions as the
  96                          *  CDCInterfaceInfo parameter. This stores each CDC interface's configuration and state information.
  97                          */
  98                         typedef struct
  99                         {
 100                                 const struct
 101                                 {
 102                                         uint8_t  ControlInterfaceNumber; /**< Interface number of the CDC control interface within the device. */
 103
 104                                         uint8_t  DataINEndpointNumber; /**< Endpoint number of the CDC interface's IN data endpoint. */
 105                                         uint16_t DataINEndpointSize; /**< Size in bytes of the CDC interface's IN data endpoint. */
 106                                         bool     DataINEndpointDoubleBank; /**< Indicates if the CDC interface's IN data endpoint should use double banking. */
 107
 108                                         uint8_t  DataOUTEndpointNumber; /**< Endpoint number of the CDC interface's OUT data endpoint. */
 109                                         uint16_t DataOUTEndpointSize;  /**< Size in bytes of the CDC interface's OUT data endpoint. */
 110                                         bool     DataOUTEndpointDoubleBank; /**< Indicates if the CDC interface's OUT data endpoint should use double banking. */
 111
 112                                         uint8_t  NotificationEndpointNumber; /**< Endpoint number of the CDC interface's IN notification endpoint, if used. */
 113                                         uint16_t NotificationEndpointSize;  /**< Size in bytes of the CDC interface's IN notification endpoint, if used. */
 114                                         bool     NotificationEndpointDoubleBank; /**< Indicates if the CDC interface's notification endpoint should use double banking. */
 115                                 } Config; /**< Config data for the USB class interface within the device. All elements in this section
 116                                            *   <b>must</b> be set or the interface will fail to enumerate and operate correctly.
 117                                            */
 118                                 struct
 119                                 {
 120                                         struct
 121                                         {
 122                                                 uint8_t HostToDevice; /**< Control line states from the host to device, as a set of CDC_CONTROL_LINE_OUT_*
 123                                                                                            *   masks. This value is updated each time \ref CDC_Device_USBTask() is called.
 124                                                                                            */
 125                                                 uint8_t DeviceToHost; /**< Control line states from the device to host, as a set of CDC_CONTROL_LINE_IN_*
 126                                                                                            *   masks - to notify the host of changes to these values, call the
 127                                                                                            *   \ref CDC_Device_SendControlLineStateChange() function.
 128                                                                                            */
 129                                         } ControlLineStates; /**< Current states of the virtual serial port's control lines between the device and host. */
 130
 131                                         struct
 132                                         {
 133                                                 uint32_t BaudRateBPS; /**< Baud rate of the virtual serial port, in bits per second. */
 134                                                 uint8_t  CharFormat; /**< Character format of the virtual serial port, a value from the
 135                                                                                           *   \ref CDC_LineEncodingFormats_t enum.
 136                                                                                           */
 137                                                 uint8_t  ParityType; /**< Parity setting of the virtual serial port, a value from the
 138                                                                                           *   \ref CDC_LineEncodingParity_t enum.
 139                                                                                           */
 140                                                 uint8_t  DataBits; /**< Bits of data per character of the virtual serial port. */
 141                                         } LineEncoding; /** Line encoding used in the virtual serial port, for the device's information. This is generally
 142                                                          *  only used if the virtual serial port data is to be reconstructed on a physical UART.
 143                                                          */
 144                                 } State; /**< State data for the USB class interface within the device. All elements in this section
 145                                           *   are reset to their defaults when the interface is enumerated.
 146                                           */
 147                         } USB_ClassInfo_CDC_Device_t;
 148
 149                 /* Function Prototypes: */
 150                         /** Configures the endpoints of a given CDC interface, ready for use. This should be linked to the library
 151                          *  \ref EVENT_USB_Device_ConfigurationChanged() event so that the endpoints are configured when the configuration containing
 152                          *  the given CDC interface is selected.
 153                          *
 154                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 155                          *
 156                          *  \return Boolean true if the endpoints were successfully configured, false otherwise.
 157                          */
 158                         bool CDC_Device_ConfigureEndpoints(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 159
 160                         /** Processes incoming control requests from the host, that are directed to the given CDC class interface. This should be
 161                          *  linked to the library \ref EVENT_USB_Device_UnhandledControlRequest() event.
 162                          *
 163                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 164                          */
 165                         void CDC_Device_ProcessControlRequest(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 166
 167                         /** General management task for a given CDC class interface, required for the correct operation of the interface. This should
 168                          *  be called frequently in the main program loop, before the master USB management task \ref USB_USBTask().
 169                          *
 170                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 171                          */
 172                         void CDC_Device_USBTask(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 173
 174                         /** CDC class driver event for a line encoding change on a CDC interface. This event fires each time the host requests a
 175                          *  line encoding change (containing the serial parity, baud and other configuration information) and may be hooked in the
 176                          *  user program by declaring a handler function with the same name and parameters listed here. The new line encoding
 177                          *  settings are available in the LineEncoding structure inside the CDC interface structure passed as a parameter.
 178                          *
 179                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 180                          */
 181                         void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 182
 183                         /** CDC class driver event for a control line state change on a CDC interface. This event fires each time the host requests a
 184                          *  control line state change (containing the virtual serial control line states, such as DTR) and may be hooked in the
 185                          *  user program by declaring a handler function with the same name and parameters listed here. The new control line states
 186                          *  are available in the ControlLineStates.HostToDevice value inside the CDC interface structure passed as a parameter, set as
 187                          *  a mask of CDC_CONTROL_LINE_OUT_* masks.
 188                          *
 189                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 190                          */
 191                         void EVENT_CDC_Device_ControLineStateChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 192
 193                         /** CDC class driver event for a send break request sent to the device from the host. This is generally used to separate
 194                          *  data or to indicate a special condition to the receiving device.
 195                          *
 196                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 197                          *  \param[in]     Duration          Duration of the break that has been sent by the host, in milliseconds.
 198                          */
 199                         void EVENT_CDC_Device_BreakSent(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo,
 200                                                         const uint8_t Duration) ATTR_NON_NULL_PTR_ARG(1);
 201
 202                         /** Sends a given string to the attached USB host, if connected. If a host is not connected when the function is called, the
 203                          *  string is discarded. Bytes will be queued for transmission to the host until either the endpoint bank becomes full, or the
 204                          *  \ref CDC_Device_Flush() function is called to flush the pending data to the host. This allows for multiple bytes to be
 205                          *  packed into a single endpoint packet, increasing data throughput.
 206                          *
 207                          *  \pre This function must only be called when the Device state machine is in the DEVICE_STATE_Configured state or
 208                          *       the call will fail.
 209                          *
 210                          *  \param[in,out]   CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 211                          *  \param[in]       Data              Pointer to the string to send to the host.
 212                          *  \param[in]       Length            Size in bytes of the string to send to the host.
 213                          *
 214                          *  \return A value from the \ref Endpoint_Stream_RW_ErrorCodes_t enum.
 215                          */
 216                         uint8_t CDC_Device_SendString(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo,
 217                                                       const char* const Data,
 218                                                       const uint16_t Length) ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2);
 219
 220                         /** Sends a given byte to the attached USB host, if connected. If a host is not connected when the function is called, the
 221                          *  byte is discarded. Bytes will be queued for transmission to the host until either the endpoint bank becomes full, or the
 222                          *  \ref CDC_Device_Flush() function is called to flush the pending data to the host. This allows for multiple bytes to be
 223                          *  packed into a single endpoint packet, increasing data throughput.
 224                          *
 225                          *  \pre This function must only be called when the Device state machine is in the DEVICE_STATE_Configured state or
 226                          *       the call will fail.
 227                          *
 228                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 229                          *  \param[in]     Data              Byte of data to send to the host.
 230                          *
 231                          *  \return A value from the \ref Endpoint_WaitUntilReady_ErrorCodes_t enum.
 232                          */
 233                         uint8_t CDC_Device_SendByte(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo,
 234                                                     const uint8_t Data) ATTR_NON_NULL_PTR_ARG(1);
 235
 236                         /** Determines the number of bytes received by the CDC interface from the host, waiting to be read. This indicates the number
 237                          *  of bytes in the OUT endpoint bank only, and thus the number of calls to \ref CDC_Device_ReceiveByte() which are guaranteed to
 238                          *  succeed immediately. If multiple bytes are to be received, they should be buffered by the user application, as the endpoint
 239                          *  bank will not be released back to the USB controller until all bytes are read.
 240                          *
 241                          *  \pre This function must only be called when the Device state machine is in the DEVICE_STATE_Configured state or
 242                          *       the call will fail.
 243                          *
 244                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 245                          *
 246                          *  \return Total number of buffered bytes received from the host.
 247                          */
 248                         uint16_t CDC_Device_BytesReceived(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 249
 250                         /** 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
 251                          *  returns a negative value. The \ref CDC_Device_BytesReceived() function may be queried in advance to determine how many
 252                          *  bytes are currently buffered in the CDC interface's data receive endpoint bank, and thus how many repeated calls to this
 253                          *  function which are guaranteed to succeed.
 254                          *
 255                          *  \pre This function must only be called when the Device state machine is in the DEVICE_STATE_Configured state or
 256                          *       the call will fail.
 257                          *
 258                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 259                          *
 260                          *  \return Next received byte from the host, or a negative value if no data received.
 261                          */
 262                         int16_t CDC_Device_ReceiveByte(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 263
 264                         /** Flushes any data waiting to be sent, ensuring that the send buffer is cleared.
 265                          *
 266                          *  \pre This function must only be called when the Device state machine is in the DEVICE_STATE_Configured state or
 267                          *       the call will fail.
 268                          *
 269                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 270                          *
 271                          *  \return A value from the \ref Endpoint_WaitUntilReady_ErrorCodes_t enum.
 272                          */
 273                         uint8_t CDC_Device_Flush(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 274
 275                         /** Sends a Serial Control Line State Change notification to the host. This should be called when the virtual serial
 276                          *  control lines (DCD, DSR, etc.) have changed states, or to give BREAK notifications to the host. Line states persist
 277                          *  until they are cleared via a second notification. This should be called each time the CDC class driver's
 278                          *  ControlLineStates.DeviceToHost value is updated to push the new states to the USB host.
 279                          *
 280                          *  \pre This function must only be called when the Device state machine is in the DEVICE_STATE_Configured state or
 281                          *       the call will fail.
 282                          *
 283                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 284                          */
 285                         void CDC_Device_SendControlLineStateChange(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 286
 287                         /** Creates a standard character stream for the given CDC Device instance so that it can be used with all the regular
 288                          *  functions in the avr-libc <stdio.h> library that accept a FILE stream as a destination (e.g. fprintf). The created
 289                          *  stream is bidirectional and can be used for both input and output functions.
 290                          *
 291                          *  Reading data from this stream is non-blocking, i.e. in most instances, complete strings cannot be read in by a single
 292                          *  fetch, as the endpoint will not be ready at some point in the transmission, aborting the transfer. However, this may
 293                          *  be used when the read data is processed byte-per-bye (via getc()) or when the user application will implement its own
 294                          *  line buffering.
 295                          *
 296                          *  \note The created stream can be given as stdout if desired to direct the standard output from all <stdio.h> functions
 297                          *        to the given CDC interface.
 298                          *
 299                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 300                          *  \param[in,out] Stream            Pointer to a FILE structure where the created stream should be placed.
 301                          */
 302                         void CDC_Device_CreateStream(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo,
 303                                                      FILE* const Stream) ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2);
 304
 305                         /** Identical to CDC_Device_CreateStream(), except that reads are blocking until the calling stream function terminates
 306                          *  the transfer. While blocking, the USB and CDC service tasks are called repeatedly to maintain USB communications.
 307                          *
 308                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state.
 309                          *  \param[in,out] Stream            Pointer to a FILE structure where the created stream should be placed.
 310                          */
 311                         void CDC_Device_CreateBlockingStream(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo,
 312                                                              FILE* const Stream) ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2);
 313
 314         /* Private Interface - For use in library only: */
 315         #if !defined(__DOXYGEN__)
 316                 /* Function Prototypes: */
 317                         #if defined(__INCLUDE_FROM_CDC_CLASS_DEVICE_C)
 318                                 static int CDC_Device_putchar(char c,
 319                                                               FILE* Stream) ATTR_NON_NULL_PTR_ARG(2);
 320                                 static int CDC_Device_getchar(FILE* Stream) ATTR_NON_NULL_PTR_ARG(1);
 321                                 static int CDC_Device_getchar_Blocking(FILE* Stream) ATTR_NON_NULL_PTR_ARG(1);
 322
 323                                 void CDC_Device_Event_Stub(void);
 324                                 void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 325                                                                           ATTR_WEAK ATTR_NON_NULL_PTR_ARG(1) ATTR_ALIAS(CDC_Device_Event_Stub);
 326                                 void EVENT_CDC_Device_ControLineStateChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 327                                                                              ATTR_WEAK ATTR_NON_NULL_PTR_ARG(1) ATTR_ALIAS(CDC_Device_Event_Stub);
 328                                 void EVENT_CDC_Device_BreakSent(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo,
 329                                                                 const uint8_t Duration) ATTR_WEAK ATTR_NON_NULL_PTR_ARG(1)
 330                                                                 ATTR_ALIAS(CDC_Device_Event_Stub);
 331                         #endif
 332
 333         #endif
 334
 335         /* Disable C linkage for C++ Compilers: */
 336                 #if defined(__cplusplus)
 337                         }
 338                 #endif
 339
 340 #endif
 341
 342 /** @} */