arch/arm/src/imx/imx_spi.c
/****************************************************************************
 * Name: spi_startxfr
 *
 * Description:
 *   If data was added to the Tx FIFO, then start the exchange
 *
 * Input Parameters:
 *   priv  - Device-specific state data
 *   ntxd  - The number of bytes added to the Tx FIFO by spi_performtx.
 *
 * Returned Value:
 *   None
 *
 ****************************************************************************/
spi_startxfr
Description:
If data was added to the Tx FIFO, then start the exchange

Input Parameters:
priv  - Device-specific state data
ntxd  - The number of bytes added to the Tx FIFO by spi_performtx.

Returned Value:
None
spi_startxfr Description : If data was added to the Tx FIFO then start the exchange Input Parameters : priv - Device - specific state data ntxd - The number of bytes added to the Tx FIFO by spi_performtx . Returned Value : None
static void spi_startxfr(struct imx_spidev_s *priv, int ntxd)
{
  uint32_t regval;
  if (ntxd > 0)
   {
      regval = spi_getreg(priv, CSPI_CTRL_OFFSET);
      regval |= CSPI_CTRL_XCH;
      spi_putreg(priv, CSPI_CTRL_OFFSET, regval);
   }
}
static void spi_startxfr ( struct imx_spidev_s * priv , int ntxd ) { uint32_t regval ; if ( ntxd > 0 ) { regval = spi_getreg ( priv , CSPI_CTRL_OFFSET ) ; regval |= CSPI_CTRL_XCH ; spi_putreg ( priv , CSPI_CTRL_OFFSET , regval ) ; } }
Name: spi_startxfr
 Description:
   If data was added to the Tx FIFO, then start the exchange
Name : spi_startxfr Description : If data was added to the Tx FIFO then start the exchange
/* The XCH bit initiates an exchange in master mode.  It remains set
   * remains set while the exchange is in progress but is automatically
   * clear when all data in the Tx FIFO and shift register are shifted out.
   * So if we have added data to the Tx FIFO on this interrupt, we must
   * set the XCH bit to resume the exchange.
   */