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Revert "nrf52_spi: support not defining MISO/MOSI pins"

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This reverts commit e91a806ab6.
This commit is contained in:
Matias N 2020-11-03 19:43:10 -03:00 committed by Mateusz Szafoni
parent e5ab2e56f8
commit 18be4198e1
3 changed files with 181 additions and 173 deletions
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19
arch/arm/src/nrf52/Kconfig
View File

@ -109,6 +109,14 @@ config NRF52_RTC
bool bool
default n default n
config NRF52_SPI_MASTER_WORKAROUND_1BYTE_TRANSFER
bool "SPI Master 1 Byte transfer anomaly workaround"
depends on NRF52_SPI_MASTER && ARCH_CHIP_NRF52832
default y
---help---
Enable the workaround to fix SPI Master 1 byte transfer bug
which occurs in NRF52832 revision 1 and revision 2.
menu "NRF52 Peripheral Selection" menu "NRF52 Peripheral Selection"
config NRF52_I2C0_MASTER config NRF52_I2C0_MASTER
@ -615,14 +623,3 @@ config NRF52_SAADC_LIMITS
endif # NRF52_SAADC endif # NRF52_SAADC
endmenu # SAADC Configuration endmenu # SAADC Configuration
menu "SPI Configuration"
config NRF52_SPI_MASTER_WORKAROUND_1BYTE_TRANSFER
bool "Master 1 Byte transfer anomaly workaround"
depends on NRF52_SPI_MASTER && ARCH_CHIP_NRF52832
default y
---help---
Enable the workaround to fix SPI Master 1 byte transfer bug
which occurs in NRF52832 revision 1 and revision 2.
endmenu

41
arch/arm/src/nrf52/hardware/nrf52_spi.h
View File

@ -153,14 +153,41 @@
#define SPIM_ENABLE_DIS (0) /* Disable SPIM */ #define SPIM_ENABLE_DIS (0) /* Disable SPIM */
#define SPIM_ENABLE_EN (0x7 << 0) /* Enable SPIM */ #define SPIM_ENABLE_EN (0x7 << 0) /* Enable SPIM */
/* PSEL(MOSI/MISO/SCK/CSN) Register */ /* PSELSCK Register */
#define SPIM_PSEL_PIN_SHIFT (0) /* Bits 0-4: pin number */ #define SPIM_PSELSCK_PIN_SHIFT (0) /* Bits 0-4: SCK pin number */
#define SPIM_PSEL_PIN_MASK (0x1f << SPIM_PSEL_PIN_SHIFT) #define SPIM_PSELSCK_PIN_MASK (0x1f << SPIM_PSELSCK_PIN_SHIFT)
#define SPIM_PSEL_PORT_SHIFT (5) /* Bit 5: port number */ #define SPIM_PSELSCK_PORT_SHIFT (5) /* Bit 5: SCK port number */
#define SPIM_PSEL_PORT_MASK (0x1 << SPIM_PSEL_PORT_SHIFT) #define SPIM_PSELSCK_PORT_MASK (0x1 << SPIM_PSELSCK_PORT_SHIFT)
#define SPIM_PSEL_CONNECTED (1 << 31) /* Bit 31: Connection */ #define SPIM_PSELSCK_CONNECTED (1 << 31) /* Bit 31: Connection */
#define SPIM_PSEL_RESET (0xffffffff) #define SPIM_PSELSCK_RESET (0xffffffff)
/* PSELMOSI Register */
#define SPIM_PSELMOSI_PIN_SHIFT (0) /* Bits 0-4: MOSI pin number */
#define SPIM_PSELMOSI_PIN_MASK (0x1f << SPIM_PSELMOSI_PIN_SHIFT)
#define SPIM_PSELMOSI_PORT_SHIFT (5) /* Bit 5: MOSI port number */
#define SPIM_PSELMOSI_PORT_MASK (0x1 << SPIM_PSELMOSI_PORT_SHIFT)
#define SPIM_PSELMOSI_CONNECTED (1 << 31) /* Bit 31: Connection */
#define SPIM_PSELMOSI_RESET (0xffffffff)
/* PSELMISO Register */
#define SPIM_PSELMISO_PIN_SHIFT (0) /* Bits 0-4: MISO pin number */
#define SPIM_PSELMISO_PIN_MASK (0x1f << SPIM_PSELMISO_PIN_SHIFT)
#define SPIM_PSELMISO_PORT_SHIFT (5) /* Bit 5: MISO port number */
#define SPIM_PSELMISO_PORT_MASK (0x1 << SPIM_PSELMISO_PORT_SHIFT)
#define SPIM_PSELMISO_CONNECTED (1 << 31) /* Bit 31: Connection */
#define SPIM_PSELMISO_RESET (0xffffffff)
/* PSELCSN Register */
#define SPIM_PSELCSN_PIN_SHIFT (0) /* Bits 0-4: CSN pin number */
#define SPIM_PSELCSN_PIN_MASK (0x1f << SPIM_PSELCSN_PIN_SHIFT)
#define SPIM_PSELCSN_PORT_SHIFT (5) /* Bit 5: CSN port number */
#define SPIM_PSELCSN_PORT_MASK (0x1 << SPIM_PSELCSN_PORT_SHIFT)
#define SPIM_PSELCSN_CONNECTED (1 << 31) /* Bit 31: Connection */
#define SPIM_PSELCSN_RESET (0xffffffff)
/* FREQUENCY Register */ /* FREQUENCY Register */

294
arch/arm/src/nrf52/nrf52_spi.c
View File

@ -72,10 +72,12 @@ struct nrf52_spidev_s
{ {
struct spi_dev_s spidev; /* Externally visible part of the SPI interface */ struct spi_dev_s spidev; /* Externally visible part of the SPI interface */
uint32_t base; /* Base address of SPI register */ uint32_t base; /* Base address of SPI register */
nrf52_pinset_t sck_pin; /* Pin settings for SPI clock */
#ifdef CONFIG_NRF52_SPI_MASTER_INTERRUPTS #ifdef CONFIG_NRF52_SPI_MASTER_INTERRUPTS
uint32_t irq; /* SPI IRQ number */ uint32_t irq; /* SPI IRQ number */
#endif #endif
uint32_t sck_pin; /* SCK pin configuration */
uint32_t mosi_pin; /* MOSI pin configuration */
uint32_t miso_pin; /* MISO pin configuration */
uint32_t frequency; /* Requested clock frequency */ uint32_t frequency; /* Requested clock frequency */
uint8_t mode; /* Mode 0,1,2,3 */ uint8_t mode; /* Mode 0,1,2,3 */
@ -97,8 +99,6 @@ static inline void nrf52_spi_putreg(FAR struct nrf52_spidev_s *priv,
static inline uint32_t nrf52_spi_getreg(FAR struct nrf52_spidev_s *priv, static inline uint32_t nrf52_spi_getreg(FAR struct nrf52_spidev_s *priv,
uint32_t offset); uint32_t offset);
static void nrf52_spi_pselinit(uint32_t pselreg, nrf52_pinset_t pinset);
/* SPI methods */ /* SPI methods */
static int nrf52_spi_lock(FAR struct spi_dev_s *dev, bool lock); static int nrf52_spi_lock(FAR struct spi_dev_s *dev, bool lock);
@ -131,7 +131,6 @@ static int nrf52_spi_isr(int irq, FAR void *context, FAR void *arg);
/* Initialization */ /* Initialization */
static int nrf52_spi_init(FAR struct nrf52_spidev_s *priv); static int nrf52_spi_init(FAR struct nrf52_spidev_s *priv);
static void nrf52_spi_gpioinit(FAR struct nrf52_spidev_s *priv);
/**************************************************************************** /****************************************************************************
* Private Data * Private Data
@ -179,9 +178,13 @@ static struct nrf52_spidev_s g_spi0dev =
}, },
.base = NRF52_SPIM0_BASE, .base = NRF52_SPIM0_BASE,
.sck_pin = BOARD_SPI0_SCK_PIN,
#ifdef CONFIG_NRF52_SPI_MASTER_INTERRUPTS #ifdef CONFIG_NRF52_SPI_MASTER_INTERRUPTS
.irq = NRF52_IRQ_SPI_TWI_0, .irq = NRF52_IRQ_SPI_TWI_0,
#endif
.sck_pin = BOARD_SPI0_SCK_PIN,
.mosi_pin = BOARD_SPI0_MOSI_PIN,
#ifdef BOARD_SPI0_MISO_PIN
.miso_pin = BOARD_SPI0_MISO_PIN,
#endif #endif
.frequency = 0, .frequency = 0,
.mode = 0 .mode = 0
@ -230,10 +233,12 @@ static struct nrf52_spidev_s g_spi1dev =
}, },
.base = NRF52_SPIM1_BASE, .base = NRF52_SPIM1_BASE,
.sck_pin = BOARD_SPI1_SCK_PIN,
#ifdef CONFIG_NRF52_SPI_MASTER_INTERRUPTS #ifdef CONFIG_NRF52_SPI_MASTER_INTERRUPTS
.irq = NRF52_IRQ_SPI_TWI_1, .irq = NRF52_IRQ_SPI_TWI_1,
#endif #endif
.sck_pin = BOARD_SPI1_SCK_PIN,
.mosi_pin = BOARD_SPI1_MOSI_PIN,
.miso_pin = BOARD_SPI1_MISO_PIN,
.frequency = 0, .frequency = 0,
.mode = 0 .mode = 0
}; };
@ -281,10 +286,12 @@ static struct nrf52_spidev_s g_spi2dev =
}, },
.base = NRF52_SPIM2_BASE, .base = NRF52_SPIM2_BASE,
.sck_pin = BOARD_SPI2_SCK_PIN,
#ifdef CONFIG_NRF52_SPI_MASTER_INTERRUPTS #ifdef CONFIG_NRF52_SPI_MASTER_INTERRUPTS
.irq = NRF52_IRQ_SPI2, .irq = NRF52_IRQ_SPI2,
#endif #endif
.sck_pin = BOARD_SPI2_SCK_PIN,
.mosi_pin = BOARD_SPI2_MOSI_PIN,
.miso_pin = BOARD_SPI2_MISO_PIN,
.frequency = 0, .frequency = 0,
.mode = 0 .mode = 0
}; };
@ -332,10 +339,12 @@ static struct nrf52_spidev_s g_spi3dev =
}, },
.base = NRF52_SPIM3_BASE, .base = NRF52_SPIM3_BASE,
.sck_pin = BOARD_SPI3_SCK_PIN,
#ifdef CONFIG_NRF52_SPI_MASTER_INTERRUPTS #ifdef CONFIG_NRF52_SPI_MASTER_INTERRUPTS
.irq = NRF52_IRQ_SPI3, .irq = NRF52_IRQ_SPI3,
#endif #endif
.sck_pin = BOARD_SPI3_SCK_PIN,
.mosi_pin = BOARD_SPI3_MOSI_PIN,
.miso_pin = BOARD_SPI3_MISO_PIN,
.frequency = 0, .frequency = 0,
.mode = 0 .mode = 0
}; };
@ -386,6 +395,7 @@ static inline uint32_t nrf52_spi_getreg(FAR struct nrf52_spidev_s *priv,
static int nrf52_spi_isr(int irq, FAR void *context, FAR void *arg) static int nrf52_spi_isr(int irq, FAR void *context, FAR void *arg)
{ {
FAR struct nrf52_spidev_s *priv = (FAR struct nrf52_spidev_s *)arg; FAR struct nrf52_spidev_s *priv = (FAR struct nrf52_spidev_s *)arg;
uint32_t regval = 0;
/* Get interrupt event */ /* Get interrupt event */
@ -404,107 +414,6 @@ static int nrf52_spi_isr(int irq, FAR void *context, FAR void *arg)
} }
#endif #endif
/****************************************************************************
* Name: nrf52_spi_pselinit
*
* Description:
* Configure PSEL for SPI devices
*
****************************************************************************/
static void nrf52_spi_pselinit(uint32_t pselreg, nrf52_pinset_t pinset)
{
uint32_t regval;
int pin = GPIO_PIN_DECODE(pinset);
int port = GPIO_PORT_DECODE(pinset);
regval = (pin << SPIM_PSEL_PIN_SHIFT);
regval |= (port << SPIM_PSEL_PORT_SHIFT);
putreg32(pselreg, regval);
}
/****************************************************************************
* Name: nrf52_spi_gpioinit
*
* Description:
* Configure GPIO for SPI pins
*
****************************************************************************/
static void nrf52_spi_gpioinit(FAR struct nrf52_spidev_s *priv)
{
nrf52_gpio_config(priv->sck_pin);
nrf52_spi_pselinit(priv->base + NRF52_SPIM_PSELSCK_OFFSET,
priv->sck_pin);
#ifdef CONFIG_NRF52_SPI0_MASTER
if (priv == &g_spi0dev)
{
#ifdef BOARD_SPI0_MISO_PIN
nrf52_gpio_config(BOARD_SPI0_MISO_PIN);
nrf52_spi_pselinit(priv->base + NRF52_SPIM_PSELMISO_OFFSET,
BOARD_SPI0_MISO_PIN);
nrf52_gpio_write(BOARD_SPI0_MISO_PIN, false);
#endif
#ifdef BOARD_SPI0_MOSI_PIN
nrf52_gpio_config(BOARD_SPI0_MOSI_PIN);
nrf52_spi_pselinit(priv->base + NRF52_SPIM_PSELMOSI_OFFSET,
BOARD_SPI0_MOSI_PIN);
#endif
}
#endif
#ifdef CONFIG_NRF52_SPI1_MASTER
if (priv == &g_spi1dev)
{
#ifdef BOARD_SPI1_MISO_PIN
nrf52_gpio_config(BOARD_SPI1_MISO_PIN);
nrf52_spi_pselinit(priv->base + NRF52_SPIM_PSELMISO_OFFSET,
BOARD_SPI1_MISO_PIN);
nrf52_gpio_write(BOARD_SPI1_MISO_PIN, false);
#endif
#ifdef BOARD_SPI1_MOSI_PIN
nrf52_gpio_config(BOARD_SPI1_MOSI_PIN);
nrf52_spi_pselinit(priv->base + NRF52_SPIM_PSELMOSI_OFFSET,
BOARD_SPI1_MOSI_PIN);
#endif
}
#endif
#ifdef CONFIG_NRF52_SPI2_MASTER
if (priv == &g_spi2dev)
{
#ifdef BOARD_SPI2_MISO_PIN
nrf52_gpio_config(BOARD_SPI2_MISO_PIN);
nrf52_spi_pselinit(priv->base + NRF52_SPIM_PSELMISO_OFFSET,
BOARD_SPI1_MISO_PIN);
nrf52_gpio_write(BOARD_SPI1_MISO_PIN, false);
#endif
#ifdef BOARD_SPI2_MOSI_PIN
nrf52_gpio_config(BOARD_SPI2_MOSI_PIN);
nrf52_spi_pselinit(priv->base + NRF52_SPIM_PSELMOSI_OFFSET,
BOARD_SPI2_MOSI_PIN);
#endif
}
#endif
#ifdef CONFIG_NRF52_SPI3_MASTER
if (priv == &g_spi3dev)
{
#ifdef BOARD_SPI3_MISO_PIN
nrf52_gpio_config(BOARD_SPI3_MISO_PIN);
nrf52_spi_pselinit(priv->base + NRF52_SPIM_PSELMISO_OFFSET,
BOARD_SPI3_MISO_PIN);
nrf52_gpio_write(BOARD_SPI1_MISO_PIN, false);
#endif
#ifdef BOARD_SPI3_MOSI_PIN
nrf52_gpio_config(BOARD_SPI3_MOSI_PIN);
nrf52_spi_pselinit(priv->base + NRF52_SPIM_PSELMOSI_OFFSET,
BOARD_SPI3_MOSI_PIN);
#endif
}
#endif
}
/**************************************************************************** /****************************************************************************
* Name: nrf52_spi_init * Name: nrf52_spi_init
* *
@ -515,18 +424,63 @@ static void nrf52_spi_gpioinit(FAR struct nrf52_spidev_s *priv)
static int nrf52_spi_init(FAR struct nrf52_spidev_s *priv) static int nrf52_spi_init(FAR struct nrf52_spidev_s *priv)
{ {
uint32_t regval = 0;
int pin = 0;
int port = 0;
/* Disable SPI */ /* Disable SPI */
nrf52_spi_putreg(priv, NRF52_SPIM_ENABLE_OFFSET, SPIM_ENABLE_DIS); nrf52_spi_putreg(priv, NRF52_SPIM_ENABLE_OFFSET, SPIM_ENABLE_DIS);
/* Configure SPI pins */ /* Configure SPI pins */
nrf52_spi_gpioinit(priv); nrf52_gpio_config(priv->sck_pin);
nrf52_gpio_config(priv->mosi_pin);
#ifdef BOARD_SPI0_MISO_PIN
nrf52_gpio_config(priv->miso_pin);
#endif
/* Select SCK pins */
pin = GPIO_PIN_DECODE(priv->sck_pin);
port = GPIO_PORT_DECODE(priv->sck_pin);
regval = (pin << SPIM_PSELSCK_PIN_SHIFT);
regval |= (port << SPIM_PSELSCK_PORT_SHIFT);
nrf52_spi_putreg(priv, NRF52_SPIM_PSELSCK_OFFSET, regval);
/* Select MOSI pins */
pin = GPIO_PIN_DECODE(priv->mosi_pin);
port = GPIO_PORT_DECODE(priv->mosi_pin);
regval = (pin << SPIM_PSELMOSI_PIN_SHIFT);
regval |= (port << SPIM_PSELMOSI_PORT_SHIFT);
nrf52_spi_putreg(priv, NRF52_SPIM_PSELMOSI_OFFSET, regval);
/* According to manual we have to write 0 to MOSI pin */
nrf52_gpio_write(priv->mosi_pin, false);
#ifdef BOARD_SPI0_MISO_PIN
/* Select MISO pins */
pin = GPIO_PIN_DECODE(priv->miso_pin);
port = GPIO_PORT_DECODE(priv->miso_pin);
regval = (pin << SPIM_PSELMISO_PIN_SHIFT);
regval |= (port << SPIM_PSELMISO_PORT_SHIFT);
nrf52_spi_putreg(priv, NRF52_SPIM_PSELMISO_OFFSET, regval);
#endif
/* NOTE: Chip select pin must be configured by board-specific logic */
#ifdef CONFIG_NRF52_SPI_MASTER_INTERRUPTS #ifdef CONFIG_NRF52_SPI_MASTER_INTERRUPTS
/* Enable interrupts for RX and TX done */ /* Enable interrupts for RX and TX done */
nrf52_spi_putreg(priv, NRF52_SPIM_INTENSET_OFFSET, SPIM_INT_END); regval = SPIM_INT_END;
nrf52_spi_putreg(priv, NRF52_SPIM_INTENSET_OFFSET, regval);
#endif #endif
/* Enable SPI */ /* Enable SPI */
@ -943,15 +897,7 @@ static void nrf52_spi_exchange(FAR struct spi_dev_s *dev,
{ {
FAR struct nrf52_spidev_s *priv = (FAR struct nrf52_spidev_s *)dev; FAR struct nrf52_spidev_s *priv = (FAR struct nrf52_spidev_s *)dev;
uint32_t regval = 0; uint32_t regval = 0;
size_t nwords_left = nwords;
if (nwords > 0xff)
{
/* MAXCNT register can only hold 8bits */
spierr("SPI transfer max of 255 bytes, %d requested\n")
DEBUGASSERT(false);
return;
}
#ifdef CONFIG_NRF52_SPI_MASTER_WORKAROUND_1BYTE_TRANSFER #ifdef CONFIG_NRF52_SPI_MASTER_WORKAROUND_1BYTE_TRANSFER
if (nwords <= 1) if (nwords <= 1)
@ -966,11 +912,6 @@ static void nrf52_spi_exchange(FAR struct spi_dev_s *dev,
regval = (uint32_t)rxbuffer; regval = (uint32_t)rxbuffer;
nrf52_spi_putreg(priv, NRF52_SPIM_RXDPTR_OFFSET, regval); nrf52_spi_putreg(priv, NRF52_SPIM_RXDPTR_OFFSET, regval);
/* Write number of bytes in RXD buffer */
regval = nwords;
nrf52_spi_putreg(priv, NRF52_SPIM_RXDMAXCNT_OFFSET, regval);
} }
else else
{ {
@ -983,51 +924,86 @@ static void nrf52_spi_exchange(FAR struct spi_dev_s *dev,
regval = (uint32_t)txbuffer; regval = (uint32_t)txbuffer;
nrf52_spi_putreg(priv, NRF52_SPIM_TXDPTR_OFFSET, regval); nrf52_spi_putreg(priv, NRF52_SPIM_TXDPTR_OFFSET, regval);
/* Write number of bytes in TXD buffer */
regval = nwords;
nrf52_spi_putreg(priv, NRF52_SPIM_TXDMAXCNT_OFFSET, regval);
} }
else else
{ {
nrf52_spi_putreg(priv, NRF52_SPIM_TXDMAXCNT_OFFSET, 0); nrf52_spi_putreg(priv, NRF52_SPIM_TXDMAXCNT_OFFSET, 0);
} }
/* SPI start */ /* If more than 255 bytes, enable list mode to send data
* in batches
*/
nrf52_spi_putreg(priv, NRF52_SPIM_TASK_START_OFFSET, SPIM_TASKS_START); if (nwords > 0xFF)
#ifndef CONFIG_NRF52_SPI_MASTER_INTERRUPTS
/* Wait for RX done and TX done */
while (nrf52_spi_getreg(priv, NRF52_SPIM_EVENTS_END_OFFSET) != 1);
/* Clear event */
nrf52_spi_putreg(priv, NRF52_SPIM_EVENTS_END_OFFSET, 0);
#else
/* Wait for transfer complete */
nxsem_wait(&priv->sem_isr);
#endif
if (nrf52_spi_getreg(priv, NRF52_SPIM_TXDAMOUNT_OFFSET) != nwords)
{ {
spierr("Incomplete transfer wrote %d expected %d\n", regval, nwords); if (rxbuffer != NULL)
{
nrf52_spi_putreg(priv, NRF52_SPIM_RXDLIST_OFFSET, 1);
}
if (txbuffer != NULL)
{
nrf52_spi_putreg(priv, NRF52_SPIM_TXDLIST_OFFSET, 1);
}
} }
/* SPI stop */ while (nwords_left > 0)
{
size_t transfer_size = (nwords_left > 255 ? 255 : nwords_left);
nrf52_spi_putreg(priv, NRF52_SPIM_TASK_STOP_OFFSET, SPIM_TASKS_STOP); if (rxbuffer != NULL)
{
/* Write number of bytes in RXD buffer */
/* Wait for STOP event */ nrf52_spi_putreg(priv, NRF52_SPIM_RXDMAXCNT_OFFSET, transfer_size);
}
while (nrf52_spi_getreg(priv, NRF52_SPIM_EVENTS_STOPPED_OFFSET) != 1); if (txbuffer != NULL)
{
/* Write number of bytes in TXD buffer */
/* Clear event */ nrf52_spi_putreg(priv, NRF52_SPIM_TXDMAXCNT_OFFSET, transfer_size);
}
nrf52_spi_putreg(priv, NRF52_SPIM_EVENTS_STOPPED_OFFSET, 0); /* SPI start */
nrf52_spi_putreg(priv, NRF52_SPIM_TASK_START_OFFSET, SPIM_TASKS_START);
#ifndef CONFIG_NRF52_SPI_MASTER_INTERRUPTS
/* Wait for RX done and TX done */
while (nrf52_spi_getreg(priv, NRF52_SPIM_EVENTS_END_OFFSET) != 1);
/* Clear event */
nrf52_spi_putreg(priv, NRF52_SPIM_EVENTS_END_OFFSET, 0);
#else
/* Wait for transfer complete */
nxsem_wait_uninterruptible(&priv->sem_isr);
#endif
if (nrf52_spi_getreg(priv, NRF52_SPIM_TXDAMOUNT_OFFSET) !=
transfer_size)
{
spierr("Incomplete transfer wrote %d expected %d\n",
regval, nwords);
}
/* SPI stop */
nrf52_spi_putreg(priv, NRF52_SPIM_TASK_STOP_OFFSET, SPIM_TASKS_STOP);
/* Wait for STOP event */
while (nrf52_spi_getreg(priv, NRF52_SPIM_EVENTS_STOPPED_OFFSET) != 1);
/* Clear event */
nrf52_spi_putreg(priv, NRF52_SPIM_EVENTS_STOPPED_OFFSET, 0);
nwords_left -= transfer_size;
}
/* Clear RX/TX DMA after transfer */ /* Clear RX/TX DMA after transfer */
@ -1036,6 +1012,14 @@ static void nrf52_spi_exchange(FAR struct spi_dev_s *dev,
nrf52_spi_putreg(priv, NRF52_SPIM_TXDPTR_OFFSET, 0); nrf52_spi_putreg(priv, NRF52_SPIM_TXDPTR_OFFSET, 0);
nrf52_spi_putreg(priv, NRF52_SPIM_TXDMAXCNT_OFFSET, 0); nrf52_spi_putreg(priv, NRF52_SPIM_TXDMAXCNT_OFFSET, 0);
/* Clear list mode */
if (nwords > 0xFF)
{
nrf52_spi_putreg(priv, NRF52_SPIM_RXDLIST_OFFSET, 0);
nrf52_spi_putreg(priv, NRF52_SPIM_TXDLIST_OFFSET, 0);
}
#ifdef CONFIG_NRF52_SPI_MASTER_WORKAROUND_1BYTE_TRANSFER #ifdef CONFIG_NRF52_SPI_MASTER_WORKAROUND_1BYTE_TRANSFER
if (nwords <= 1) if (nwords <= 1)
{ {