spidev.h

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/*
 * include/linux/spi/spidev.h
 *
 * Copyright (C) 2006 SWAPP
 *  Andrea Paterniani <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */

#ifndef SPIDEV_H
#define SPIDEV_H

#include <linux/types.h>

/* User space versions of kernel symbols for SPI clocking modes,
 * matching <linux/spi/spi.h>
 */

#define SPI_CPHA        0x01
#define SPI_CPOL        0x02

#define SPI_MODE_0      (0|0)
#define SPI_MODE_1      (0|SPI_CPHA)
#define SPI_MODE_2      (SPI_CPOL|0)
#define SPI_MODE_3      (SPI_CPOL|SPI_CPHA)

#define SPI_CS_HIGH     0x04
#define SPI_LSB_FIRST       0x08
#define SPI_3WIRE       0x10
#define SPI_LOOP        0x20
#define SPI_NO_CS       0x40
#define SPI_READY       0x80

/*---------------------------------------------------------------------------*/

/* IOCTL commands */

#define SPI_IOC_MAGIC           'k'

struct spi_ioc_transfer {
    __u64       tx_buf;
    __u64       rx_buf;

    __u32       len;
    __u32       speed_hz;

    __u16       delay_usecs;
    __u8        bits_per_word;
    __u8        cs_change;
    __u32       pad;

    /* If the contents of 'struct spi_ioc_transfer' ever change
     * incompatibly, then the ioctl number (currently 0) must change;
     * ioctls with constant size fields get a bit more in the way of
     * error checking than ones (like this) where that field varies.
     *
     * NOTE: struct layout is the same in 64bit and 32bit userspace.
     */
};

/* not all platforms use <asm-generic/ioctl.h> or _IOC_TYPECHECK() ... */
#define SPI_MSGSIZE(N) \
    ((((N)*(sizeof (struct spi_ioc_transfer))) < (1 << _IOC_SIZEBITS)) \
        ? ((N)*(sizeof (struct spi_ioc_transfer))) : 0)
#define SPI_IOC_MESSAGE(N) _IOW(SPI_IOC_MAGIC, 0, char[SPI_MSGSIZE(N)])


/* Read / Write of SPI mode (SPI_MODE_0..SPI_MODE_3) */
#define SPI_IOC_RD_MODE         _IOR(SPI_IOC_MAGIC, 1, __u8)
#define SPI_IOC_WR_MODE         _IOW(SPI_IOC_MAGIC, 1, __u8)

/* Read / Write SPI bit justification */
#define SPI_IOC_RD_LSB_FIRST        _IOR(SPI_IOC_MAGIC, 2, __u8)
#define SPI_IOC_WR_LSB_FIRST        _IOW(SPI_IOC_MAGIC, 2, __u8)

/* Read / Write SPI device word length (1..N) */
#define SPI_IOC_RD_BITS_PER_WORD    _IOR(SPI_IOC_MAGIC, 3, __u8)
#define SPI_IOC_WR_BITS_PER_WORD    _IOW(SPI_IOC_MAGIC, 3, __u8)

/* Read / Write SPI device default max speed hz */
#define SPI_IOC_RD_MAX_SPEED_HZ     _IOR(SPI_IOC_MAGIC, 4, __u32)
#define SPI_IOC_WR_MAX_SPEED_HZ     _IOW(SPI_IOC_MAGIC, 4, __u32)



#endif /* SPIDEV_H */