diff options
Diffstat (limited to 'include/spi.h')
| -rw-r--r-- | include/spi.h | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/include/spi.h b/include/spi.h index 8fd7b2e311..49bddd3cc3 100644 --- a/include/spi.h +++ b/include/spi.h @@ -64,17 +64,22 @@ extern const unsigned int spi_devices_used; */ int spi_enable(int port, int enable); +#define SPI_READBACK_ALL (-1) + /* Issue a SPI transaction. Assumes SPI port has already been enabled. * * Transmits <txlen> bytes from <txdata>, throwing away the corresponding * received data, then transmits <rxlen> dummy bytes, saving the received data * in <rxdata>. + * If SPI_READBACK_ALL is set in <rxlen>, the received data during transmission + * is recorded in rxdata buffer and it assumes that the real <rxlen> is equal + * to <txlen>. * * @param spi_device the SPI device to use * @param txdata buffer to transmit * @param txlen number of bytes in txdata. * @param rxdata receive buffer. - * @param rxlen number of bytes in rxdata. + * @param rxlen number of bytes in rxdata or SPI_READBACK_ALL. */ int spi_transaction(const struct spi_device_t *spi_device, const uint8_t *txdata, int txlen, @@ -91,6 +96,9 @@ int spi_transaction_async(const struct spi_device_t *spi_device, /* Wait for async response received */ int spi_transaction_flush(const struct spi_device_t *spi_device); +/* Wait for async response received but do not de-assert chip select */ +int spi_transaction_wait(const struct spi_device_t *spi_device); + #ifdef CONFIG_SPI /** * Called when the NSS level changes, signalling the start or end of a SPI |