sys/arch/evbarm/mpcsa/mpcsa_spi.c

   1 /*      $Id: mpcsa_spi.c,v 1.2 2008/07/03 01:15:39 matt Exp $   */
   2 /*      $NetBSD$        */
   3
   4 /*
   5  * Copyright (c) 2007 Embedtronics Oy. All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 __KERNEL_RCSID(0, "$NetBSD$");
  31
  32 #include <sys/param.h>
  33 #include <sys/systm.h>
  34 #include <sys/kernel.h>
  35 #include <sys/device.h>
  36 #include <sys/lock.h>
  37 #include <arm/at91/at91reg.h>
  38 #include <arm/at91/at91var.h>
  39 #include <arm/at91/at91spivar.h>
  40 #include <arm/at91/at91piovar.h>
  41
  42 #ifdef MPCSA_SPI_DEBUG
  43 int mpcsa_spi_debug = MPCSA_SPI_DEBUG;
  44 #define DPRINTFN(n,x)   if (mpcsa_spi_debug>(n)) printf x;
  45 #else
  46 #define DPRINTFN(n,x)
  47 #endif
  48
  49 struct at91pio_softc;
  50
  51 struct mpcsa_spi_softc {
  52         struct at91spi_softc    sc_dev;
  53         struct at91pio_softc    *sc_pioa, *sc_piod;
  54 };
  55
  56 static int mpcsa_spi_match(struct device *, struct cfdata *, void *);
  57 static void mpcsa_spi_attach(struct device *, struct device *, void *);
  58
  59 CFATTACH_DECL(mpcsa_spi, sizeof(struct mpcsa_spi_softc),
  60               mpcsa_spi_match, mpcsa_spi_attach, NULL, NULL);
  61
  62 static int mpcsa_spi_select(void *self, int sel);
  63
  64 struct at91spi_machdep mpcsa_spi_tag = {
  65         mpcsa_spi_select
  66 };
  67
  68 static int
  69 mpcsa_spi_match(struct device *parent, struct cfdata *match, void *aux)
  70 {
  71         if (strcmp(match->cf_name, "at91spi") == 0 && strcmp(match->cf_atname, "mpcsa_spi") == 0)
  72                 return 2;
  73         return 0;
  74 }
  75
  76 #define GPIO_SPICS0(func)       (func)(sc->sc_pioa, 3)
  77 #define GPIO_SPICS1(func)       (func)(sc->sc_pioa, 4)
  78 #define GPIO_SPICS2(func)       (func)(sc->sc_piod, 19)
  79
  80
  81 static void
  82 mpcsa_spi_attach(struct device *parent, struct device *self, void *aux)
  83 {
  84         struct mpcsa_spi_softc *sc = (struct mpcsa_spi_softc *)self;
  85
  86         // do some checks
  87         if ((sc->sc_pioa = at91pio_sc(AT91_PIOA)) == NULL) {
  88                 printf("no PIOA!\n");
  89                 return;
  90         }
  91         if ((sc->sc_piod = at91pio_sc(AT91_PIOD)) == NULL) {
  92                 printf("no PIOD!\n");
  93                 return;
  94         }
  95
  96         // initialize softc
  97         sc->sc_dev.sc_spi.sct_nslaves = 3;      // number of slaves
  98
  99         // configure GPIO
 100         GPIO_SPICS0(at91pio_out); GPIO_SPICS0(at91pio_set);
 101         GPIO_SPICS1(at91pio_out); GPIO_SPICS1(at91pio_set);
 102         GPIO_SPICS2(at91pio_out); GPIO_SPICS2(at91pio_set);
 103
 104         // and call common routine
 105         at91spi_attach_common(parent, self, aux, &mpcsa_spi_tag);
 106 }
 107
 108 static int mpcsa_spi_select(void *self, int sel)
 109 {
 110         struct mpcsa_spi_softc *sc = (struct mpcsa_spi_softc *)self;
 111
 112         /* first deselect everything */
 113         GPIO_SPICS0(at91pio_set);
 114         GPIO_SPICS1(at91pio_set);
 115         GPIO_SPICS2(at91pio_set);
 116
 117         /* then select wanted target */
 118         switch (sel) {
 119         case -1:
 120           break;
 121         case 0:
 122           GPIO_SPICS0(at91pio_clear);
 123           break;
 124         case 1:
 125           GPIO_SPICS2(at91pio_clear);
 126           break;
 127         case 2:
 128           GPIO_SPICS2(at91pio_clear);
 129           break;
 130         default:
 131           return EINVAL;
 132         }
 133
 134         return 0;
 135 }