sys/dev/spi/spivar.h

   1 /* $NetBSD: spivar.h,v 1.2 2006/10/07 07:21:13 gdamore Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2006 Urbana-Champaign Independent Media Center.
   5  * Copyright (c) 2006 Garrett D'Amore.
   6  * All rights reserved.
   7  *
   8  * Portions of this code were written by Garrett D'Amore for the
   9  * Champaign-Urbana Community Wireless Network Project.
  10  *
  11  * Redistribution and use in source and binary forms, with or
  12  * without modification, are permitted provided that the following
  13  * conditions are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above
  17  *    copyright notice, this list of conditions and the following
  18  *    disclaimer in the documentation and/or other materials provided
  19  *    with the distribution.
  20  * 3. All advertising materials mentioning features or use of this
  21  *    software must display the following acknowledgements:
  22  *      This product includes software developed by the Urbana-Champaign
  23  *      Independent Media Center.
  24  *      This product includes software developed by Garrett D'Amore.
  25  * 4. Urbana-Champaign Independent Media Center's name and Garrett
  26  *    D'Amore's name may not be used to endorse or promote products
  27  *    derived from this software without specific prior written permission.
  28  *
  29  * THIS SOFTWARE IS PROVIDED BY THE URBANA-CHAMPAIGN INDEPENDENT
  30  * MEDIA CENTER AND GARRETT D'AMORE ``AS IS'' AND ANY EXPRESS OR
  31  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  32  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  33  * ARE DISCLAIMED.  IN NO EVENT SHALL THE URBANA-CHAMPAIGN INDEPENDENT
  34  * MEDIA CENTER OR GARRETT D'AMORE BE LIABLE FOR ANY DIRECT, INDIRECT,
  35  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  36  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  37  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  38  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  40  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  41  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  42  */
  43
  44 #ifndef _DEV_SPI_SPIVAR_H_
  45 #define _DEV_SPI_SPIVAR_H_
  46
  47 #include <sys/queue.h>
  48 #include <sys/simplelock.h>
  49
  50 /*
  51  * Serial Peripheral Interface bus.  This is a 4-wire bus common for
  52  * connecting flash, clocks, sensors, and various other low-speed
  53  * peripherials.
  54  */
  55
  56 struct spi_handle;
  57 struct spi_transfer;
  58
  59 /*
  60  * De facto standard latching modes.
  61  */
  62 #define SPI_MODE_0      0       /* CPOL = 0, CPHA = 0 */
  63 #define SPI_MODE_1      1       /* CPOL = 0, CPHA = 1 */
  64 #define SPI_MODE_2      2       /* CPOL = 1, CPHA = 0 */
  65 #define SPI_MODE_3      3       /* CPOL = 1, CPHA = 1 */
  66 /* Philips' Microwire is just Mode 0 */
  67 #define SPI_MODE_MICROWIRE      SPI_MODE_0
  68
  69 struct spi_controller {
  70         void    *sct_cookie;    /* controller private data */
  71         int     sct_nslaves;
  72         int     (*sct_configure)(void *, int, int, int);
  73         int     (*sct_transfer)(void *, struct spi_transfer *);
  74 };
  75
  76 int spibus_print(void *, const char *);
  77
  78 /* one per chip select */
  79 struct spibus_attach_args {
  80         struct spi_controller   *sba_controller;
  81 };
  82
  83 struct spi_attach_args {
  84         struct spi_handle       *sa_handle;
  85 };
  86
  87 /*
  88  * This is similar in some respects to struct buf, but we cannot use
  89  * that structure because it was not designed to support full-duplex
  90  * IO.
  91  */
  92 struct spi_chunk {
  93         struct spi_chunk *chunk_next;
  94         int             chunk_count;
  95         uint8_t         *chunk_read;
  96         const uint8_t   *chunk_write;
  97         /* for private use by framework and bus driver */
  98         uint8_t         *chunk_rptr;
  99         const uint8_t   *chunk_wptr;
 100         int             chunk_rresid;
 101         int             chunk_wresid;
 102 };
 103
 104 struct spi_transfer {
 105         struct spi_chunk *st_chunks;            /* chained bufs */
 106         SIMPLEQ_ENTRY(spi_transfer) st_chain;   /* chain of submitted jobs */
 107         int             st_flags;
 108         int             st_errno;
 109         int             st_slave;
 110         void            *st_private;
 111         void            (*st_done)(struct spi_transfer *);
 112         struct simplelock       st_lock;
 113         void            *st_busprivate;
 114 };
 115
 116 /* declare a list of transfers */
 117 SIMPLEQ_HEAD(spi_transq, spi_transfer);
 118
 119 #define spi_transq_init(q)      \
 120         SIMPLEQ_INIT(q)
 121
 122 #define spi_transq_enqueue(q, trans)    \
 123         SIMPLEQ_INSERT_TAIL(q, trans, st_chain)
 124
 125 #define spi_transq_dequeue(q)           \
 126         SIMPLEQ_REMOVE_HEAD(q, st_chain)
 127
 128 #define spi_transq_first(q)             \
 129         SIMPLEQ_FIRST(q)
 130
 131 #define SPI_F_DONE              0x0001
 132 #define SPI_F_ERROR             0x0002
 133
 134 int spi_configure(struct spi_handle *, int mode, int speed);
 135 int spi_transfer(struct spi_handle *, struct spi_transfer *);
 136 void spi_transfer_init(struct spi_transfer *);
 137 void spi_chunk_init(struct spi_chunk *, int, const uint8_t *, uint8_t *);
 138 void spi_transfer_add(struct spi_transfer *, struct spi_chunk *);
 139 void spi_wait(struct spi_transfer *);
 140 void spi_done(struct spi_transfer *, int);
 141
 142 /* convenience wrappers */
 143 int spi_send(struct spi_handle *, int, const uint8_t *);
 144 int spi_recv(struct spi_handle *, int, uint8_t *);
 145 int spi_send_recv(struct spi_handle *, int, const uint8_t *, int, uint8_t *);
 146
 147 #endif  /* _DEV_SPI_SPIVAR_H_ */