diff options
| -rw-r--r-- | nuttx/arch/arm/src/efm32/efm32_spi.c | 68 |
1 files changed, 25 insertions, 43 deletions
diff --git a/nuttx/arch/arm/src/efm32/efm32_spi.c b/nuttx/arch/arm/src/efm32/efm32_spi.c index 6b631c904..1a67d4306 100644 --- a/nuttx/arch/arm/src/efm32/efm32_spi.c +++ b/nuttx/arch/arm/src/efm32/efm32_spi.c @@ -166,11 +166,11 @@ struct efm32_spidev_s sem_t exclsem; /* Supports mutually exclusive access */ uint32_t frequency; /* Requested clock frequency */ uint32_t actual; /* Actual clock frequency */ - uint8_t nbits; /* Width of word in bits (8 or 16) */ uint8_t mode; /* Mode 0,1,2,3 */ #endif - bool initialized; /* True: Already initialized */ + uint8_t nbits; /* Width of word in bits (8 or 16) */ + bool initialized; /* True: Already initialized */ }; /**************************************************************************** @@ -182,7 +182,6 @@ static uint32_t spi_getreg(const struct efm32_spiconfig_s *config, unsigned int regoffset); static void spi_putreg(const struct efm32_spiconfig_s *config, unsigned int regoffset, uint32_t regval); -static bool spi_16bitmode(struct efm32_spidev_s *priv); static void spi_rxflush(const struct efm32_spiconfig_s *config); static void spi_wait_status(const struct efm32_spiconfig_s *config, uint32_t mask, uint32_t match); @@ -390,34 +389,6 @@ static void spi_putreg(const struct efm32_spiconfig_s *config, } /**************************************************************************** - * Name: spi_16bitmode - * - * Description: - * Return true if the transfer is performed on 16-bit (vs 8-bit) data. - * - * Input Parameters: - * priv - Device-specific state data - * - * Returned Value: - * True: 16-bit; false: 8-bit - * - ****************************************************************************/ - -static bool spi_16bitmode(struct efm32_spidev_s *priv) -{ -#ifndef CONFIG_SPI_OWNBUS - return (priv->nbits > 8) ? true : false; -#else - uint32_t regval; - - regval = spi_getreg(config, EFM32_USART_FRAME_OFFSET); - regval &= _USART_FRAME_DATABITS_MASK; - regval >>= _USART_FRAME_DATABITS_SHIFT; - return (regval > _USART_FRAME_DATABITS_EIGHT); -#endif -} - -/**************************************************************************** * Name: spi_rxflush * * Description: @@ -645,7 +616,7 @@ static void spi_dmarxsetup(struct efm32_spidev_s *priv, void *rxbuffer, /* 8- or 16-bit mode? */ - if (spi_16bitmode(priv)) + if (priv->nbits > 8) { /* 16-bit mode -- is there a buffer to receive data in? */ @@ -703,7 +674,7 @@ static void spi_dmatxsetup(struct efm32_spidev_s *priv, const void *txbuffer, /* 8- or 16-bit mode? */ - if (spi_16bitmode(priv)) + if (priv->nbits > 8) { /* 16-bit mode -- is there a buffer to receive data in? */ @@ -874,6 +845,7 @@ static uint32_t spi_setfrequency(struct spi_dev_s *dev, uint32_t frequency) struct efm32_spidev_s *priv = (struct efm32_spidev_s *)dev; const struct efm32_spiconfig_s *config; uint32_t clkdiv; + uint32_t actual; DEBUGASSERT(priv && priv->config); config = priv->config; @@ -881,9 +853,15 @@ static uint32_t spi_setfrequency(struct spi_dev_s *dev, uint32_t frequency) /* Has the frequency changed? */ #ifndef CONFIG_SPI_OWNBUS - if (frequency != priv->frequency) + if (frequency == priv->frequency) { + /* No... just return the actual frequency from the last calcualtion */ + + actual = priv->actual; + } + else #endif + { /* We want to use integer division to avoid forcing in float division * utils, and yet keep rounding effect errors to a minimum. * @@ -928,7 +906,14 @@ static uint32_t spi_setfrequency(struct spi_dev_s *dev, uint32_t frequency) clkdiv &= _USART_CLKDIV_DIV_MASK; spi_putreg(config, EFM32_USART_CLKDIV_OFFSET, clkdiv); - spivdbg("Frequency %d\n", frequency); + /* The actual frequency is then given by: + * + * br = fHFPERCLK / (2 * (1 + CLKDIV / 256)) + * = 128 * fHFPERCLK / (256 + CLKDIV) + */ + + actual = (BOARD_HFPERCLK_FREQUENCY << 7) / ( 256 + clkdiv); + spivdbg("frequency=%u actual=%u\n", frequency, actual); #ifndef CONFIG_SPI_OWNBUS /* Save the frequency selection so that subsequent reconfigurations @@ -936,10 +921,11 @@ static uint32_t spi_setfrequency(struct spi_dev_s *dev, uint32_t frequency) */ priv->frequency = frequency; - } + priv->actual = actual; #endif + } - return frequency; + return actual; } /**************************************************************************** @@ -1041,10 +1027,8 @@ static void spi_setbits(struct spi_dev_s *dev, int nbits) /* Has the number of bits changed? */ -#ifndef CONFIG_SPI_OWNBUS if (nbits != priv->nbits) { -#endif regval = spi_getreg(config, EFM32_USART_CTRL_OFFSET); if (nbits < 0) { @@ -1122,14 +1106,12 @@ static void spi_setbits(struct spi_dev_s *dev, int nbits) regval |= setting; spi_putreg(config, EFM32_USART_FRAME_OFFSET, regval); -#ifndef CONFIG_SPI_OWNBUS /* Save the selection so the subsequence re-configurations will be * faster */ priv->nbits = nbits; } -#endif } /**************************************************************************** @@ -1292,7 +1274,7 @@ static void spi_exchange(struct spi_dev_s *dev, const void *txbuffer, /* 8- or 16-bit mode? */ - if (spi_16bitmode(priv)) + if (priv->nbits > 8) { /* 16-bit mode */ @@ -1592,9 +1574,9 @@ static int spi_portinitialize(struct efm32_spidev_s *priv) #ifndef CONFIG_SPI_OWNBUS priv->frequency = 0; - priv->nbits = 8; priv->mode = SPIDEV_MODE0; #endif + priv->nbits = 8; /* 8 bits */ |