diff options
author | patacongo <patacongo@7fd9a85b-ad96-42d3-883c-3090e2eb8679> | 2011-10-07 22:37:24 +0000 |
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committer | patacongo <patacongo@7fd9a85b-ad96-42d3-883c-3090e2eb8679> | 2011-10-07 22:37:24 +0000 |
commit | ab982a0a316133dcf870bac7137c03db60768aaa (patch) | |
tree | f6a1df9d8409cbb2e66bacb04f7aaeb344800d3a /nuttx/arch/arm/src/sam3u | |
parent | d69c8839f26d5d6cc677e79188dcff7198fff13c (diff) |
SAM3U SPI debug changes
git-svn-id: https://nuttx.svn.sourceforge.net/svnroot/nuttx/trunk@4031 7fd9a85b-ad96-42d3-883c-3090e2eb8679
Diffstat (limited to 'nuttx/arch/arm/src/sam3u')
-rw-r--r-- | nuttx/arch/arm/src/sam3u/sam3u_spi.c | 57 |
1 files changed, 46 insertions, 11 deletions
diff --git a/nuttx/arch/arm/src/sam3u/sam3u_spi.c b/nuttx/arch/arm/src/sam3u/sam3u_spi.c index 753f023559..fb83e9312e 100644 --- a/nuttx/arch/arm/src/sam3u/sam3u_spi.c +++ b/nuttx/arch/arm/src/sam3u/sam3u_spi.c @@ -125,7 +125,9 @@ static void spi_dumpregs(FAR const char *msg); #else # define spi_dumpregs(msg) #endif + static inline void spi_flush(void); +static inline uint32_t spi_cs2pcs(FAR struct sam3u_spidev_s *priv); /* SPI methods */ @@ -222,7 +224,7 @@ static void spi_dumpregs(FAR const char *msg) spivdbg(" CSR0:%08x CSR1:%08x CSR2:%08x CSR3:%08x\n", getreg32(SAM3U_SPI_CSR0), getreg32(SAM3U_SPI_CSR1), getreg32(SAM3U_SPI_CSR2), getreg32(SAM3U_SPI_CSR3)); - spivdbg(" WPCR:%08x WPSR:%08x IMR:%08x\n", + spivdbg(" WPCR:%08x WPSR:%08x\n", getreg32(SAM3U_SPI_WPCR), getreg32(SAM3U_SPI_WPSR)); } #endif @@ -258,6 +260,37 @@ static inline void spi_flush(void) } /**************************************************************************** + * Name: spi_cs2pcs + * + * Description: + * Map the chip select number to the bit-set PCS field used in the SPI + * registers. A chip select number is used for indexing and identifying + * chip selects. However, the chip select information is represented by + * a bit set in the SPI regsisters. This function maps those chip select + * numbers to the correct bit set: + * + * CS Returned Spec Effective + * No. PCS Value NPCS + * ---- -------- -------- -------- + * 0 0000 xxx0 1110 + * 1 0001 xx01 1101 + * 2 0011 x011 1011 + * 3 0111 0111 0111 + * + * Input Parameters: + * priv - Device-specific state data + * + * Returned Value: + * None + * + ****************************************************************************/ + +static inline uint32_t spi_cs2pcs(FAR struct sam3u_spidev_s *priv) +{ + return ((uint32_t)1 << (priv->cs)) - 1; +} + +/**************************************************************************** * Name: spi_lock * * Description: @@ -346,9 +379,9 @@ static int spi_lock(FAR struct spi_dev_s *dev, bool lock) * in order to select a slave. */ - regval = getreg32(SAM3U_SPI_MR); + regval = getreg32(SAM3U_SPI_MR); regval &= ~SPI_MR_PCS_MASK; - regval |= (priv->cs << SPI_MR_PCS_SHIFT); + regval |= (spi_cs2pcs(priv) << SPI_MR_PCS_SHIFT); putreg32(regval, SAM3U_SPI_MR); } else @@ -660,16 +693,18 @@ static void spi_exchange(FAR struct spi_dev_s *dev, FAR const void *txbuffer, FAR void *rxbuffer, size_t nwords) { -#ifdef CONFIG_SPI_VARSELECT FAR struct sam3u_spidev_s *priv = (FAR struct sam3u_spidev_s *)dev; - uint32_t tdr = (uint32_t)priv->cs << SPI_TDR_PCS_SHIFT; -#endif FAR uint8_t *rxptr = (FAR uint8_t*)rxbuffer; FAR uint8_t *txptr = (FAR uint8_t*)txbuffer; + uint32_t pcs; uint32_t data; spivdbg("txbuffer=%p rxbuffer=%p nwords=%d\n", txbuffer, rxbuffer, nwords); + /* Set up PCS bits */ + + pcs = spi_cs2pcs(priv) << SPI_TDR_PCS_SHIFT; + /* Make sure that any previous transfer is flushed from the hardware */ spi_flush(); @@ -718,13 +753,13 @@ static void spi_exchange(FAR struct spi_dev_s *dev, data = 0xffff; } - /* Set the chip select in the value written to the TDR */ + /* Set the PCS field in the value written to the TDR */ -#ifdef CONFIG_SPI_VARSELECT - data |= tdr; + data |= pcs; /* Do we need to set the LASTXFER bit in the TDR value too? */ +#ifdef CONFIG_SPI_VARSELECT if (nwords == 1) { data |= SPI_TDR_LASTXFER; @@ -734,7 +769,7 @@ static void spi_exchange(FAR struct spi_dev_s *dev, /* Wait for any previous data written to the TDR to be transferred * to the serializer. */ - + while ((getreg32(SAM3U_SPI_SR) & SPI_INT_TDRE) == 0); /* Write the data to transmitted to the Transmit Data Register (TDR) */ @@ -750,7 +785,7 @@ static void spi_exchange(FAR struct spi_dev_s *dev, data = getreg32(SAM3U_SPI_RDR); if (rxptr) { - *txptr++ = (uint8_t)data; + *rxptr++ = (uint8_t)data; } } } |