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/* 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 */
#define SPI_MOSI_IDLE_LOW  _BITUL(17) /* leave MOSI line low when idle */
#define SPI_MOSI_IDLE_HIGH _BITUL(18) /* leave MOSI line high when idle */

/*
 * 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(19) - 1)

#endif /* _SPI_H */