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      1 /*	$Id: mpcsa_spi.c,v 1.3 2012/10/27 17:17:48 chs Exp $	*/
      2 /*	$NetBSD: mpcsa_spi.c,v 1.3 2012/10/27 17:17:48 chs Exp $	*/
      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: mpcsa_spi.c,v 1.3 2012/10/27 17:17:48 chs Exp $");
     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_at91spi;
     53 	struct at91pio_softc	*sc_pioa, *sc_piod;
     54 };
     55 
     56 static int mpcsa_spi_match(device_t, cfdata_t, void *);
     57 static void mpcsa_spi_attach(device_t, device_t, void *);
     58 
     59 CFATTACH_DECL_NEW(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(device_t parent, cfdata_t 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(device_t parent, device_t self, void *aux)
     83 {
     84 	struct mpcsa_spi_softc *sc = device_private(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_at91spi.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 = device_private(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 }
    136