tool/mbed/mbed-sdk/libraries/net/cellular/CellularUSBModem/serial/io/IOSerialStream.cpp

   1 /* IOSerialStream.cpp */
   2 /* Copyright (C) 2012 mbed.org, MIT License
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
   5  * and associated documentation files (the "Software"), to deal in the Software without restriction,
   6  * including without limitation the rights to use, copy, modify, merge, publish, distribute,
   7  * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
   8  * furnished to do so, subject to the following conditions:
   9  *
  10  * The above copyright notice and this permission notice shall be included in all copies or
  11  * substantial portions of the Software.
  12  *
  13  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
  14  * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  15  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
  16  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  17  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  18  */
  19
  20 #define __DEBUG__ 0 //Maximum verbosity
  21 #ifndef __MODULE__
  22 #define __MODULE__ "IOSerialStream.cpp"
  23 #endif
  24
  25 #include "core/fwk.h"
  26
  27 #include <cstring>
  28
  29 #include "IOSerialStream.h"
  30
  31 #define UART_X ((LPC_UART_TypeDef *)(UART_1))
  32
  33 IOSerialStream::IOSerialStream(mbed::RawSerial& serial) : m_serial(serial), m_serialTxFifoEmpty(true),
  34 m_availableSphre(1), m_spaceSphre(1), m_inBuf(), m_outBuf()
  35 {
  36   m_availableSphre.wait();
  37   m_spaceSphre.wait();
  38   //Attach interrupts
  39   m_serial.attach(this, &IOSerialStream::readable, mbed::SerialBase::RxIrq);
  40   m_serial.attach(this, &IOSerialStream::writeable, mbed::SerialBase::TxIrq);
  41 }
  42
  43 /*virtual*/ IOSerialStream::~IOSerialStream()
  44 {
  45   m_serial.attach(NULL, mbed::SerialBase::RxIrq);
  46   m_serial.attach(NULL, mbed::SerialBase::TxIrq);
  47 }
  48
  49 //0 for non-blocking (returns immediately), osWaitForever for infinite blocking
  50 /*virtual*/ int IOSerialStream::read(uint8_t* buf, size_t* pLength, size_t maxLength, uint32_t timeout/*=osWaitForever*/)
  51 {
  52   DBG("Trying to read at most %d chars", maxLength);
  53   int ret = waitAvailable(timeout);
  54   if(ret)
  55   {
  56     WARN("Error %d while waiting for incoming data", ret);
  57     return ret;
  58   }
  59   int readLen = MIN( available(), maxLength );
  60   *pLength = readLen;
  61   setupReadableISR(false);
  62   while(readLen--)
  63   {
  64     m_inBuf.dequeue(buf);
  65     buf++;
  66   }
  67   setupReadableISR(true);
  68   DBG("Read %d chars successfully", *pLength);
  69   return OK;
  70 }
  71
  72 /*virtual*/ size_t IOSerialStream::available()
  73 {
  74   setupReadableISR(false); //m_inBuf.available() is not reentrant
  75   size_t len = m_inBuf.available();
  76   setupReadableISR(true);
  77   return len;
  78 }
  79
  80 /*virtual*/ int IOSerialStream::waitAvailable(uint32_t timeout/*=osWaitForever*/) //Wait for data to be available
  81 {
  82   int ret;
  83   if(available()) //Is data already available?
  84   {
  85     m_availableSphre.wait(0); //Clear the queue as data is available
  86     return OK;
  87   }
  88
  89   DBG("Waiting for data availability %d ms (-1 is infinite)", timeout);
  90   ret = m_availableSphre.wait(timeout); //Wait for data to arrive or for abort
  91   if(ret <= 0)
  92   {
  93     DBG("Timeout");
  94     return NET_TIMEOUT;
  95   }
  96   if(!available()) //Even if abort has been called, return that data is available
  97   {
  98     DBG("Aborted");
  99     return NET_INTERRUPTED;
 100   }
 101   DBG("Finished waiting");
 102   m_availableSphre.wait(0); //Clear the queue as data is available
 103   return OK;
 104 }
 105
 106 /*virtual*/ int IOSerialStream::abortRead() //Abort current reading (or waiting) operation
 107 {
 108   if( !available() ) //If there is data pending, no need to abort
 109   {
 110     m_availableSphre.release(); //Force exiting the waiting state; kludge to pass a RC directly
 111   }
 112   else
 113   {
 114     DBG("Serial is readable"); ;
 115   }
 116   return OK;
 117 }
 118
 119 void IOSerialStream::setupReadableISR(bool en)
 120 {
 121   if(en)
 122   {
 123     UART_X->IER |= 1 << 0;
 124   }
 125   else
 126   {
 127     UART_X->IER &= ~(1 << 0);
 128   }
 129 }
 130
 131 void IOSerialStream::readable() //Callback from m_serial when new data is available
 132 {
 133   do
 134   {
 135     m_inBuf.queue(m_serial.getc());
 136   } while(m_serial.readable());
 137   m_availableSphre.release(); //Force exiting the waiting state
 138 }
 139
 140 //0 for non-blocking (returns immediately), osWaitForever for infinite blocking
 141 /*virtual*/ int IOSerialStream::write(uint8_t* buf, size_t length, uint32_t timeout/*=osWaitForever*/)
 142 {
 143   DBG("Trying to write %d chars", length);
 144   int ret = waitSpace(timeout);
 145   if(ret)
 146   {
 147     WARN("Error %d while waiting for space", ret);
 148     return ret;
 149   }
 150   DBG("Writing %d chars", length);
 151   setupWriteableISR(false);
 152   while(length)
 153   {
 154     m_outBuf.queue(*buf);
 155     buf++;
 156     length--;
 157     if(length && !space())
 158     {
 159       DBG("Waiting to write remaining %d chars", length);
 160       setupWriteableISR(true);
 161       ret = waitSpace(timeout);
 162       if(ret)
 163       {
 164         WARN("Error %d while waiting for space", ret);
 165         return ret;
 166       }
 167       setupWriteableISR(false);
 168     }
 169   }
 170   //If m_serial tx fifo is empty we need to manually tx a byte in order to trigger the interrupt
 171   if( m_outBuf.available() && m_serialTxFifoEmpty )
 172   {
 173     m_serialTxFifoEmpty = false;
 174     uint8_t c;
 175     m_outBuf.dequeue(&c);
 176     m_serial.putc((char)c);
 177   }
 178   setupWriteableISR(true);
 179   DBG("Write successful");
 180   return OK;
 181 }
 182
 183 /*virtual*/ size_t IOSerialStream::space()
 184 {
 185   setupWriteableISR(false); //m_outBuf.available() is not reentrant
 186   size_t len = CIRCBUF_SIZE - m_outBuf.available();
 187   setupWriteableISR(true);
 188   return len;
 189 }
 190
 191 /*virtual*/ int IOSerialStream::waitSpace(uint32_t timeout/*=osWaitForever*/) //Wait for space to be available
 192 {
 193   int ret;
 194   if(space()) //Is still space already left?
 195   {
 196     m_spaceSphre.wait(0); //Clear the queue as space is available
 197     return OK;
 198   }
 199
 200   DBG("Waiting for data space %d ms (-1 is infinite)", timeout);
 201   ret = m_spaceSphre.wait(timeout); //Wait for space to be made or for abort
 202   if(ret <= 0)
 203   {
 204     DBG("Timeout");
 205     return NET_TIMEOUT;
 206   }
 207   if(!space()) //Even if abort has been called, return that space is available
 208   {
 209     DBG("Aborted");
 210     return NET_INTERRUPTED;
 211   }
 212   m_spaceSphre.wait(0); //Clear the queue as space is available
 213   return OK;
 214 }
 215
 216 /*virtual*/ int IOSerialStream::abortWrite() //Abort current writing (or waiting) operation
 217 {
 218   if( !space() ) //If there is space left, no need to abort
 219   {
 220     m_spaceSphre.release(); //Force exiting the waiting state
 221   }
 222   return OK;
 223 }
 224
 225 void IOSerialStream::setupWriteableISR(bool en)
 226 {
 227   if(en)
 228   {
 229     UART_X->IER |= 1 << 1;
 230   }
 231   else
 232   {
 233     UART_X->IER &= ~(1 << 1);
 234   }
 235 }
 236
 237 void IOSerialStream::writeable() //Callback from m_serial when new space is available
 238 {
 239   if(m_outBuf.isEmpty())
 240   {
 241     m_serialTxFifoEmpty = true;
 242   }
 243   else
 244   {
 245     while(m_serial.writeable() && !m_outBuf.isEmpty())
 246     {
 247       uint8_t c;
 248       m_outBuf.dequeue(&c);
 249       m_serial.putc((char)c);
 250     }
 251   }
 252   m_spaceSphre.release(); //Force exiting the waiting state
 253 }