|SPI_W8R8(9)||Serial Peripheral Interface (S||SPI_W8R8(9)|
spi_w8r8 - SPI synchronous 8 bit write followed by 8 bit read
ssize_t spi_w8r8(struct spi_device * spi, u8 cmd);
Callable only from contexts that can sleep.
the (unsigned) eight bit number returned by the device, or else a negative error code.
|January 2017||Kernel Hackers Manual 4.8.|