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stm32f0l0g0/stm32_spi.c: fix receiving data for half duplex mode

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This commit is contained in:
raiden00pl 2022-07-22 10:32:10 +02:00 committed by Xiang Xiao
parent 351c9dc837
commit 8eae3bb5ff
1 changed files with 106 additions and 13 deletions
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119
arch/arm/src/stm32f0l0g0/stm32_spi.c
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@ -184,6 +184,8 @@ struct stm32_spidev_s
struct pm_callback_s pm_cb; /* PM callbacks */
#endif
enum spi_config_e config; /* full/half duplex, simplex transmit/read only */
bool rx_now; /* Half duplex only: receiving data now */
bool rx_mode; /* Half duplex only: SPI_CR1_BIDIOE bit status */
};
/****************************************************************************
@ -196,6 +198,7 @@ static inline uint16_t spi_getreg(struct stm32_spidev_s *priv,
uint8_t offset);
static inline void spi_putreg(struct stm32_spidev_s *priv,
uint8_t offset, uint16_t value);
static inline void spi_rx_mode(struct stm32_spidev_s *priv, bool enable);
static inline uint16_t spi_readword(struct stm32_spidev_s *priv);
static inline void spi_writeword(struct stm32_spidev_s *priv,
uint16_t byte);
@ -430,6 +433,62 @@ static inline void spi_putreg(struct stm32_spidev_s *priv,
putreg16(value, priv->spibase + offset);
}
/****************************************************************************
* Name: spi_rx_mode
*
* Description:
* Activate SPI RX or SPI TX for the half-duplex mode
*
****************************************************************************/
static inline void spi_rx_mode(struct stm32_spidev_s *priv, bool enable)
{
if (enable)
{
/* Enable RX */
if (!priv->rx_mode)
{
/* Disable SPI */
spi_modifycr(STM32_SPI_CR1_OFFSET, priv, 0, SPI_CR1_SPE);
/* Disable output for half-duplex mode - SPI starts to
* automatically output clocks.
*/
spi_modifycr(STM32_SPI_CR1_OFFSET, priv, 0, SPI_CR1_BIDIOE);
/* Enable SPI */
spi_modifycr(STM32_SPI_CR1_OFFSET, priv, SPI_CR1_SPE, 0);
priv->rx_mode = true;
}
}
else
{
/* Enable TX */
if (priv->rx_mode)
{
/* Disable SPI */
spi_modifycr(STM32_SPI_CR1_OFFSET, priv, 0, SPI_CR1_SPE);
/* Enable TX output */
spi_modifycr(STM32_SPI_CR1_OFFSET, priv, SPI_CR1_BIDIOE, 0);
/* Enable SPI */
spi_modifycr(STM32_SPI_CR1_OFFSET, priv, SPI_CR1_SPE, 0);
priv->rx_mode = false;
}
}
}
/****************************************************************************
* Name: spi_getreg8
*
@ -495,15 +554,18 @@ static inline uint16_t spi_readword(struct stm32_spidev_s *priv)
if (priv->config == HALF_DUPLEX)
{
/* Disable output for half-duplex mode */
spi_modifycr(STM32_SPI_CR1_OFFSET, priv, 0, SPI_CR1_BIDIOE);
spi_rx_mode(priv, true);
}
/* Wait until the receive buffer is not empty */
while ((spi_getreg(priv, STM32_SPI_SR_OFFSET) & SPI_SR_RXNE) == 0);
if (priv->config == HALF_DUPLEX)
{
spi_rx_mode(priv, false);
}
/* Then return the received byte */
return spi_getreg(priv, STM32_SPI_DR_OFFSET);
@ -536,9 +598,7 @@ static inline void spi_writeword(struct stm32_spidev_s *priv,
if (priv->config == HALF_DUPLEX)
{
/* Enable output for half-duplex mode */
spi_modifycr(STM32_SPI_CR1_OFFSET, priv, SPI_CR1_BIDIOE, 0);
spi_rx_mode(priv, false);
}
/* Wait until the transmit buffer is empty */
@ -576,6 +636,13 @@ static inline void spi_writeword(struct stm32_spidev_s *priv,
{
spi_putreg(priv, STM32_SPI_DR_OFFSET, word);
}
if (priv->config == HALF_DUPLEX)
{
/* Wait for data transfer to be completed */
while ((spi_getreg(priv, STM32_SPI_SR_OFFSET) & SPI_SR_BSY) != 0);
}
}
/****************************************************************************
@ -1289,12 +1356,32 @@ static uint32_t spi_send(struct spi_dev_s *dev, uint32_t wd)
{
struct stm32_spidev_s *priv = (struct stm32_spidev_s *)dev;
uint32_t regval;
uint32_t ret;
uint32_t ret = 0;
DEBUGASSERT(priv && priv->spibase);
spi_writeword(priv, (uint16_t)(wd & 0xffff));
ret = (uint32_t)spi_readword(priv);
if (priv->config != HALF_DUPLEX)
{
spi_writeword(priv, (uint16_t)(wd & 0xffff));
ret = (uint32_t)spi_readword(priv);
}
else
{
/* In half duplex we must send data and receive data in separate
* spi_send() calls.
*/
if (!priv->rx_now)
{
spi_writeword(priv, (uint16_t)(wd & 0xffff));
}
else
{
ret = (uint32_t)spi_readword(priv);
priv->rx_now = false;
}
}
/* Check and clear any error flags (Reading from the SR clears the error
* flags)
@ -1361,10 +1448,12 @@ static void spi_exchange_nodma(struct spi_dev_s *dev,
if (src)
{
word = *src++;
priv->rx_now = false;
}
else
{
word = 0xffff;
priv->rx_now = true;
}
/* Exchange one word */
@ -1394,10 +1483,12 @@ static void spi_exchange_nodma(struct spi_dev_s *dev,
if (src)
{
word = *src++;
priv->rx_now = false;
}
else
{
word = 0xff;
priv->rx_now = true;
}
/* Exchange one word */
@ -1746,8 +1837,9 @@ static void spi_bus_initialize(struct stm32_spidev_s *priv)
setbits |= SPI_CR1_RXONLY;
break;
case HALF_DUPLEX:
clrbits |= SPI_CR1_BIDIOE | SPI_CR1_RXONLY;
setbits |= SPI_CR1_BIDIMODE;
clrbits |= SPI_CR1_RXONLY;
setbits |= SPI_CR1_BIDIOE | SPI_CR1_BIDIMODE; /* TX mode */
priv->rx_mode = false;
break;
}
@ -1787,8 +1879,9 @@ static void spi_bus_initialize(struct stm32_spidev_s *priv)
setbits |= SPI_CR1_RXONLY;
break;
case HALF_DUPLEX:
clrbits |= SPI_CR1_BIDIOE | SPI_CR1_RXONLY;
setbits |= SPI_CR1_BIDIMODE;
clrbits |= SPI_CR1_RXONLY;
setbits |= SPI_CR1_BIDIOE | SPI_CR1_BIDIMODE; /* TX mode */
priv->rx_mode = false;
break;
}