diff options
| author | Dragos Bogdan <dragos.bogdan@analog.com> | 2020-12-21 18:29:35 +0300 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2020-12-28 17:21:31 +0300 |
| commit | d962608ce2188a1d46ec9d356d6fad5cd6fc0341 (patch) | |
| tree | e129ab2ad7f2227640351917584bbf0ebb65da6e /include/uapi/linux/spi/spi.h | |
| parent | f7005142dacea1769fba0152c493aaa61b33205c (diff) | |
| download | linux-d962608ce2188a1d46ec9d356d6fad5cd6fc0341.tar.xz | |
spi: Add SPI_NO_TX/RX support
Transmit/receive only is a valid SPI mode. For example, the MOSI/TX line
might be missing from an ADC while for a DAC the MISO/RX line may be
optional. This patch adds these two new modes: SPI_NO_TX and
SPI_NO_RX. This way, the drivers will be able to identify if any of
these two lines is missing and to adjust the transfers accordingly.
Signed-off-by: Dragos Bogdan <dragos.bogdan@analog.com>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20201221152936.53873-2-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'include/uapi/linux/spi/spi.h')
| -rw-r--r-- | include/uapi/linux/spi/spi.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/include/uapi/linux/spi/spi.h b/include/uapi/linux/spi/spi.h index 703b586f35df..236a85f08ded 100644 --- a/include/uapi/linux/spi/spi.h +++ b/include/uapi/linux/spi/spi.h @@ -28,4 +28,14 @@ #define SPI_RX_OCTAL _BITUL(14) /* receive with 8 wires */ #define SPI_3WIRE_HIZ _BITUL(15) /* high impedance turnaround */ +/* + * All the bits defined above should be covered by SPI_MODE_USER_MASK. + * The SPI_MODE_USER_MASK has the SPI_MODE_KERNEL_MASK counterpart in + * 'include/linux/spi/spi.h'. The bits defined here are from bit 0 upwards + * while in SPI_MODE_KERNEL_MASK they are from the other end downwards. + * These bits must not overlap. A static assert check should make sure of that. + * If adding extra bits, make sure to increase the bit index below as well. + */ +#define SPI_MODE_USER_MASK (_BITUL(16) - 1) + #endif /* _UAPI_SPI_H */ |