spi: tegra114: add 3 wire transfer mode support

This patch adds 3 wire transfer support to SPI mode list along with
its implementation.

3 wire or Bi-directional mode uses only one serial data pin for the
transfer. SPI in master mode uses MOSI data line only and MISO data
line is not used.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Sowjanya Komatineni 2019-04-04 17:14:08 -07:00 committed by Mark Brown
parent 9877a347f2
commit 9d199231b0
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@ -754,6 +754,11 @@ static u32 tegra_spi_setup_transfer_one(struct spi_device *spi,
else
command1 &= ~SPI_LSBIT_FE;
if (spi->mode & SPI_3WIRE)
command1 |= SPI_BIDIROE;
else
command1 &= ~SPI_BIDIROE;
if (tspi->cs_control) {
if (tspi->cs_control != spi)
tegra_spi_writel(tspi, command1, SPI_COMMAND1);
@ -1158,7 +1163,7 @@ static int tegra_spi_probe(struct platform_device *pdev)
/* the spi->mode bits understood by this driver: */
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST |
SPI_TX_DUAL | SPI_RX_DUAL;
SPI_TX_DUAL | SPI_RX_DUAL | SPI_3WIRE;
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
master->setup = tegra_spi_setup;
master->transfer_one_message = tegra_spi_transfer_one_message;