On 03/19/2015 03:01 AM, kernel@xxxxxxxxxxxxxxxx wrote: > diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c > @@ -201,6 +202,9 @@ static int bcm2835_spi_start_transfer( > cdiv = 0; /* 0 is the slowest we can go */ > } > > + if ((spi->mode & SPI_3WIRE) && (tfr->rx_buf)) > + cs |= BCM2835_SPI_CS_REN; > + I can see how that tells the HW which direction to transfer data in 3WIRE mode, but how does the HW know whether it's in 3WIRE mode or has separate RX/TX lines? -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html