linux-headers/linux/spi/spi.h
2023-06-07 11:35:51 +00:00

43 lines
1.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
#ifndef _SPI_H
#define _SPI_H
#include <linux/const.h>
#define SPI_CPHA _BITUL(0) /* clock phase */
#define SPI_CPOL _BITUL(1) /* clock polarity */
#define SPI_MODE_0 (0|0) /* (original MicroWire) */
#define SPI_MODE_1 (0|SPI_CPHA)
#define SPI_MODE_2 (SPI_CPOL|0)
#define SPI_MODE_3 (SPI_CPOL|SPI_CPHA)
#define SPI_MODE_X_MASK (SPI_CPOL|SPI_CPHA)
#define SPI_CS_HIGH _BITUL(2) /* chipselect active high? */
#define SPI_LSB_FIRST _BITUL(3) /* per-word bits-on-wire */
#define SPI_3WIRE _BITUL(4) /* SI/SO signals shared */
#define SPI_LOOP _BITUL(5) /* loopback mode */
#define SPI_NO_CS _BITUL(6) /* 1 dev/bus, no chipselect */
#define SPI_READY _BITUL(7) /* slave pulls low to pause */
#define SPI_TX_DUAL _BITUL(8) /* transmit with 2 wires */
#define SPI_TX_QUAD _BITUL(9) /* transmit with 4 wires */
#define SPI_RX_DUAL _BITUL(10) /* receive with 2 wires */
#define SPI_RX_QUAD _BITUL(11) /* receive with 4 wires */
#define SPI_CS_WORD _BITUL(12) /* toggle cs after each word */
#define SPI_TX_OCTAL _BITUL(13) /* transmit with 8 wires */
#define SPI_RX_OCTAL _BITUL(14) /* receive with 8 wires */
#define SPI_3WIRE_HIZ _BITUL(15) /* high impedance turnaround */
#define SPI_RX_CPHA_FLIP _BITUL(16) /* flip CPHA on Rx only xfer */
/*
* 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(17) - 1)
#endif /* _SPI_H */