adc_fetch.cxx

// dawn/src/io/adc_fetch.cxx
//
// SPDX-License-Identifier: Apache-2.0
//
 
#include "dawn/io/adc_fetch.hxx"
 
using namespace dawn;
 
int CIOAdcFetch::getDataImpl(IODataCmn &data, size_t len)
{
  auto *dst = static_cast<uint8_t *>(data.getDataPtr());
  size_t expected = getDataSize();
  size_t total = 0;
  int ret;
 
  if (len != 1)
    {
      return -ENOTSUP;
    }
 
  if (data.getItems() < getChans())
    {
      return -ENOMEM;
    }
 
  ret = adc_start(getFdInternal());
  if (ret < 0)
    {
      return ret;
    }
 
  // Drain the whole conversion - a short read leaves samples in the FIFO
  // and rotates the channel order of the next fetch
 
  while (total < expected)
    {
      ret = adc_read(getFdInternal(),
                     reinterpret_cast<dawn::porting::adc_read_s *>(dst + total),
                     expected - total);
      if (ret < 0)
        {
          return ret;
        }
 
      if (ret == 0)
        {
          return -EIO;
        }
 
      total += static_cast<size_t>(ret);
    }
 
#ifdef CONFIG_DAWN_IO_TIMESTAMP
  if (isTimestamp())
    {
      data.getTs() = getTimestamp();
    }
#endif
 
  return OK;
}
 
int CIOAdcFetch::doStart()
{
  return OK;
}
 
int CIOAdcFetch::doStop()
{
  return OK;
}
 
int CIOAdcFetch::trigger(uint8_t cmd)
{
  UNUSED(cmd);
  return adc_start(getFdInternal());
}