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 /** \ingroup Group_USBClassCDC
  32  *  @defgroup Group_USBClassCDCDevice CDC Class Device Mode Driver
  33  *
  34  *  \section Sec_Dependencies Module Source Dependencies
  35  *  The following files must be built with any user project that uses this module:
  36  *    - LUFA/Drivers/USB/Class/Device/CDC.c
  37  *
  38  *  \section Module Description
  39  *  Device Mode USB Class driver framework interface, for the CDC USB Class driver.
  40  *
  41  *  \note There are several major drawbacks to the CDC-ACM standard USB class, however
  42  *        it is very standardized and thus usually available as a built-in driver on
  43  *        most platforms, and so is a better choice than a proprietary serial class.
  44  *
  45  *        One major issue with CDC-ACM is that it requires two Interface descriptors,
  46  *        which will upset most hosts when part of a multi-function "Composite" USB
  47  *        device, as each interface will be loaded into a separate driver instance. To
  48  *        conbat this, you should use the "Interface Association Descriptor" addendum to
  49  *        the USB standard which is available on most OSes when creating Composite devices.
  50  *
  51  *        Another major oversight is that there is no mechanism for the host to notify the
  52  *        device that there is a data sink on the host side ready to accept data. This
  53  *        means that the device may try to send data while the host isn't listening, causing
  54  *        lengthy blocking timeouts in the transmission routines. To combat this, it is
  55  *        recommended that the virtual serial line DTR (Data Terminal Ready) be used where
  56  *        possible to determine if a host application is ready for data.
  57  *
  58  *  @{
  59  */
  60
  61 #ifndef _CDC_CLASS_DEVICE_H_
  62 #define _CDC_CLASS_DEVICE_H_
  63
  64         /* Includes: */
  65                 #include "../../USB.h"
  66                 #include "../Common/CDC.h"
  67
  68                 #include <stdio.h>
  69                 #include <string.h>
  70
  71         /* Enable C linkage for C++ Compilers: */
  72                 #if defined(__cplusplus)
  73                         extern "C" {
  74                 #endif
  75
  76         /* Preprocessor Checks: */
  77                 #if !defined(__INCLUDE_FROM_CDC_DRIVER)
  78                         #error Do not include this file directly. Include LUFA/Drivers/Class/CDC.h instead.
  79                 #endif
  80
  81         /* Public Interface - May be used in end-application: */
  82                 /* Type Defines: */
  83                         /** Class state structure. An instance of this structure should be made for each CDC interface
  84                          *  within the user application, and passed to each of the CDC class driver functions as the
  85                          *  CDCInterfaceInfo parameter. This stores each CDC interface's configuration and state information.
  86                          */
  87                         typedef struct
  88                         {
  89                                 const struct
  90                                 {
  91                                         uint8_t  ControlInterfaceNumber; /**< Interface number of the CDC control interface within the device */
  92
  93                                         uint8_t  DataINEndpointNumber; /**< Endpoint number of the CDC interface's IN data endpoint */
  94                                         uint16_t DataINEndpointSize; /**< Size in bytes of the CDC interface's IN data endpoint */
  95                                         bool     DataINEndpointDoubleBank; /** Indicates if the CDC interface's IN data endpoint should use double banking */
  96
  97                                         uint8_t  DataOUTEndpointNumber; /**< Endpoint number of the CDC interface's OUT data endpoint */
  98                                         uint16_t DataOUTEndpointSize;  /**< Size in bytes of the CDC interface's OUT data endpoint */
  99                                         bool     DataOUTEndpointDoubleBank; /** Indicates if the CDC interface's OUT data endpoint should use double banking */
 100
 101                                         uint8_t  NotificationEndpointNumber; /**< Endpoint number of the CDC interface's IN notification endpoint, if used */
 102                                         uint16_t NotificationEndpointSize;  /**< Size in bytes of the CDC interface's IN notification endpoint, if used */
 103                                         bool     NotificationEndpointDoubleBank; /** Indicates if the CDC interface's notification endpoint should use double banking */
 104                                 } Config; /**< Config data for the USB class interface within the device. All elements in this section
 105                                            *   <b>must</b> be set or the interface will fail to enumerate and operate correctly.
 106                                            */
 107                                 struct
 108                                 {
 109                                         struct
 110                                         {
 111                                                 uint8_t HostToDevice; /**< Control line states from the host to device, as a set of CDC_CONTROL_LINE_OUT_*
 112                                                                                            *   masks. This value is updated each time \ref CDC_Device_USBTask() is called.
 113                                                                                            */
 114                                                 uint8_t DeviceToHost; /**< Control line states from the device to host, as a set of CDC_CONTROL_LINE_IN_*
 115                                                                                            *   masks - to notify the host of changes to these values, call the
 116                                                                                            *   \ref CDC_Device_SendControlLineStateChange() function.
 117                                                                                            */
 118                                         } ControlLineStates; /**< Current states of the virtual serial port's control lines between the device and host. */
 119
 120                                         struct
 121                                         {
 122                                                 uint32_t BaudRateBPS; /**< Baud rate of the virtual serial port, in bits per second */
 123                                                 uint8_t  CharFormat; /**< Character format of the virtual serial port, a value from the
 124                                                                                           *   CDCDevice_CDC_LineCodingFormats_t enum
 125                                                                                           */
 126                                                 uint8_t  ParityType; /**< Parity setting of the virtual serial port, a value from the
 127                                                                                           *   CDCDevice_LineCodingParity_t enum
 128                                                                                           */
 129                                                 uint8_t  DataBits; /**< Bits of data per character of the virtual serial port */
 130                                         } LineEncoding; /** Line encoding used in the virtual serial port, for the device's information. This is generally
 131                                                          *  only used if the virtual serial port data is to be reconstructed on a physical UART.
 132                                                          */
 133                                 } State; /**< State data for the USB class interface within the device. All elements in this section
 134                                           *   are reset to their defaults when the interface is enumerated.
 135                                           */
 136                         } USB_ClassInfo_CDC_Device_t;
 137
 138                 /* Function Prototypes: */
 139                         /** Configures the endpoints of a given CDC interface, ready for use. This should be linked to the library
 140                          *  \ref EVENT_USB_Device_ConfigurationChanged() event so that the endpoints are configured when the configuration containing
 141                          *  the given CDC interface is selected.
 142                          *
 143                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state
 144                          *
 145                          *  \return Boolean true if the endpoints were successfully configured, false otherwise
 146                          */
 147                         bool CDC_Device_ConfigureEndpoints(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 148
 149                         /** Processes incoming control requests from the host, that are directed to the given CDC class interface. This should be
 150                          *  linked to the library \ref EVENT_USB_Device_UnhandledControlRequest() event.
 151                          *
 152                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state
 153                          */
 154                         void CDC_Device_ProcessControlRequest(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 155
 156                         /** General management task for a given CDC class interface, required for the correct operation of the interface. This should
 157                          *  be called frequently in the main program loop, before the master USB management task \ref USB_USBTask().
 158                          *
 159                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state
 160                          */
 161                         void CDC_Device_USBTask(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 162
 163                         /** CDC class driver event for a line encoding change on a CDC interface. This event fires each time the host requests a
 164                          *  line encoding change (containing the serial parity, baud and other configuration information) and may be hooked in the
 165                          *  user program by declaring a handler function with the same name and parameters listed here. The new line encoding
 166                          *  settings are available in the LineEncoding structure inside the CDC interface structure passed as a parameter.
 167                          *
 168                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state
 169                          */
 170                         void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 171
 172                         /** CDC class driver event for a control line state change on a CDC interface. This event fires each time the host requests a
 173                          *  control line state change (containing the virtual serial control line states, such as DTR) and may be hooked in the
 174                          *  user program by declaring a handler function with the same name and parameters listed here. The new control line states
 175                          *  are available in the ControlLineStates.HostToDevice value inside the CDC interface structure passed as a parameter, set as
 176                          *  a mask of CDC_CONTROL_LINE_OUT_* masks.
 177                          *
 178                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state
 179                          */
 180                         void EVENT_CDC_Device_ControLineStateChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 181
 182                         /** Sends a given string to the attached USB host, if connected. If a host is not connected when the function is called, the
 183                          *  string is discarded. Bytes will be queued for transmission to the host until either the endpoint bank becomes full, or the
 184                          *  \ref CDC_Device_Flush() function is called to flush the pending data to the host. This allows for multiple bytes to be
 185                          *  packed into a single endpoint packet, increasing data throughput.
 186                          *
 187                          *  \note This function must only be called when the Device state machine is in the DEVICE_STATE_Configured state or
 188                          *        the call will fail.
 189                          *
 190                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state
 191                          *  \param[in] Data  Pointer to the string to send to the host
 192                          *  \param[in] Length  Size in bytes of the string to send to the host
 193                          *
 194                          *  \return A value from the \ref Endpoint_Stream_RW_ErrorCodes_t enum
 195                          */
 196                         uint8_t CDC_Device_SendString(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo, char* const Data, const uint16_t Length)
 197                                                       ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2);
 198
 199                         /** Sends a given byte to the attached USB host, if connected. If a host is not connected when the function is called, the
 200                          *  byte is discarded. Bytes will be queued for transmission to the host until either the endpoint bank becomes full, or the
 201                          *  \ref CDC_Device_Flush() function is called to flush the pending data to the host. This allows for multiple bytes to be
 202                          *  packed into a single endpoint packet, increasing data throughput.
 203                          *
 204                          *  \note This function must only be called when the Device state machine is in the DEVICE_STATE_Configured state or
 205                          *        the call will fail.
 206                          *
 207                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state
 208                          *  \param[in] Data  Byte of data to send to the host
 209                          *
 210                          *  \return A value from the \ref Endpoint_WaitUntilReady_ErrorCodes_t enum
 211                          */
 212                         uint8_t CDC_Device_SendByte(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo, const uint8_t Data) ATTR_NON_NULL_PTR_ARG(1);
 213
 214                         /** Determines the number of bytes received by the CDC interface from the host, waiting to be read.
 215                          *
 216                          *  \note This function must only be called when the Device state machine is in the DEVICE_STATE_Configured state or
 217                          *        the call will fail.
 218                          *
 219                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state
 220                          *
 221                          *  \return Total number of buffered bytes received from the host
 222                          */
 223                         uint16_t CDC_Device_BytesReceived(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 224
 225                         /** 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
 226                          *  returns 0. The \ref CDC_Device_BytesReceived() function should be queried before data is received to ensure that no data
 227                          *  underflow occurs.
 228                          *
 229                          *  \note This function must only be called when the Device state machine is in the DEVICE_STATE_Configured state or
 230                          *        the call will fail.
 231                          *
 232                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state
 233                          *
 234                          *  \return Next received byte from the host, or 0 if no data received
 235                          */
 236                         uint8_t CDC_Device_ReceiveByte(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 237
 238                         /** Flushes any data waiting to be sent, ensuring that the send buffer is cleared.
 239                          *
 240                          *  \note This function must only be called when the Device state machine is in the 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 A value from the \ref Endpoint_WaitUntilReady_ErrorCodes_t enum
 246                          */
 247                         uint8_t CDC_Device_Flush(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 248
 249                         /** Sends a Serial Control Line State Change notification to the host. This should be called when the virtual serial
 250                          *  control lines (DCD, DSR, etc.) have changed states, or to give BREAK notifications to the host. Line states persist
 251                          *  until they are cleared via a second notification. This should be called each time the CDC class driver's
 252                          *  ControlLineStates.DeviceToHost value is updated to push the new states to the USB host.
 253                          *
 254                          *  \note This function must only be called when the Device state machine is in the 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                         void CDC_Device_SendControlLineStateChange(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 260
 261                         /** Creates a standard characer stream for the given CDC Device instance so that it can be used with all the regular
 262                          *  functions in the avr-libc <stdio.h> library that accept a FILE stream as a destination (e.g. fprintf). The created
 263                          *  stream is bidirectional and can be used for both input and output functions.
 264                          *
 265                          *  Reading data from this stream is non-blocking, i.e. in most instances, complete strings cannot be read in by a single
 266                          *  fetch, as the endpoint will not be ready at some point in the transmission, aborting the transfer. However, this may
 267                          *  be used when the read data is processed byte-per-bye (via getc()) or when the user application will implement its own
 268                          *  line buffering.
 269                          *
 270                          *  \note The created stream can be given as stdout if desired to direct the standard output from all <stdio.h> functions
 271                          *        to the given CDC interface.
 272                          *
 273                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state
 274                          *  \param[in,out] Stream  Pointer to a FILE structure where the created stream should be placed
 275                          */
 276                         void CDC_Device_CreateStream(USB_ClassInfo_CDC_Device_t* CDCInterfaceInfo, FILE* Stream);
 277
 278                         /** Identical to CDC_Device_CreateStream(), except that reads are blocking until the calling stream function terminates
 279                          *  the transfer. While blocking, the USB and CDC service tasks are called repeatedly to maintain USB communications.
 280                          *
 281                          *  \param[in,out] CDCInterfaceInfo  Pointer to a structure containing a CDC Class configuration and state
 282                          *  \param[in,out] Stream  Pointer to a FILE structure where the created stream should be placed
 283                          */
 284                         void CDC_Device_CreateBlockingStream(USB_ClassInfo_CDC_Device_t* CDCInterfaceInfo, FILE* Stream);
 285
 286         /* Private Interface - For use in library only: */
 287         #if !defined(__DOXYGEN__)
 288                 /* Function Prototypes: */
 289                         #if defined(__INCLUDE_FROM_CDC_CLASS_DEVICE_C)
 290                                 static int CDC_Device_putchar(char c, FILE* Stream);
 291                                 static int CDC_Device_getchar(FILE* Stream);
 292                                 static int CDC_Device_getchar_Blocking(FILE* Stream);
 293
 294                                 void CDC_Device_Event_Stub(void);
 295                                 void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 296                                                                                                                   ATTR_WEAK ATTR_NON_NULL_PTR_ARG(1) ATTR_ALIAS(CDC_Device_Event_Stub);
 297                                 void EVENT_CDC_Device_ControLineStateChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 298                                                                                                                          ATTR_WEAK ATTR_NON_NULL_PTR_ARG(1) ATTR_ALIAS(CDC_Device_Event_Stub);
 299                         #endif
 300
 301         #endif
 302
 303         /* Disable C linkage for C++ Compilers: */
 304                 #if defined(__cplusplus)
 305                         }
 306                 #endif
 307
 308 #endif
 309
 310 /** @} */