/*      $Id: mpcsa_spi.c,v 1.3 2012/10/27 17:17:48 chs Exp $    */
/*      $NetBSD: mpcsa_spi.c,v 1.3 2012/10/27 17:17:48 chs Exp $        */

/*
* Copyright (c) 2007 Embedtronics Oy. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: mpcsa_spi.c,v 1.3 2012/10/27 17:17:48 chs Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/device.h>
#include <sys/lock.h>
#include <arm/at91/at91reg.h>
#include <arm/at91/at91var.h>
#include <arm/at91/at91spivar.h>
#include <arm/at91/at91piovar.h>

#ifdef MPCSA_SPI_DEBUG
int mpcsa_spi_debug = MPCSA_SPI_DEBUG;
#define DPRINTFN(n,x)   if (mpcsa_spi_debug>(n)) printf x;
#else
#define DPRINTFN(n,x)
#endif

struct at91pio_softc;

struct mpcsa_spi_softc {
       struct at91spi_softc    sc_at91spi;
       struct at91pio_softc    *sc_pioa, *sc_piod;
};

static int mpcsa_spi_match(device_t, cfdata_t, void *);
static void mpcsa_spi_attach(device_t, device_t, void *);

CFATTACH_DECL_NEW(mpcsa_spi, sizeof(struct mpcsa_spi_softc),
             mpcsa_spi_match, mpcsa_spi_attach, NULL, NULL);

static int mpcsa_spi_select(void *self, int sel);

struct at91spi_machdep mpcsa_spi_tag = {
       mpcsa_spi_select
};

static int
mpcsa_spi_match(device_t parent, cfdata_t match, void *aux)
{
       if (strcmp(match->cf_name, "at91spi") == 0 && strcmp(match->cf_atname, "mpcsa_spi") == 0)
               return 2;
       return 0;
}

#define GPIO_SPICS0(func)       (func)(sc->sc_pioa, 3)
#define GPIO_SPICS1(func)       (func)(sc->sc_pioa, 4)
#define GPIO_SPICS2(func)       (func)(sc->sc_piod, 19)


static void
mpcsa_spi_attach(device_t parent, device_t self, void *aux)
{
       struct mpcsa_spi_softc *sc = device_private(self);

       // do some checks
       if ((sc->sc_pioa = at91pio_sc(AT91_PIOA)) == NULL) {
               printf("no PIOA!\n");
               return;
       }
       if ((sc->sc_piod = at91pio_sc(AT91_PIOD)) == NULL) {
               printf("no PIOD!\n");
               return;
       }

       // initialize softc
       sc->sc_at91spi.sc_spi.sct_nslaves = 3;  // number of slaves

       // configure GPIO
       GPIO_SPICS0(at91pio_out); GPIO_SPICS0(at91pio_set);
       GPIO_SPICS1(at91pio_out); GPIO_SPICS1(at91pio_set);
       GPIO_SPICS2(at91pio_out); GPIO_SPICS2(at91pio_set);

       // and call common routine
       at91spi_attach_common(parent, self, aux, &mpcsa_spi_tag);
}

static int mpcsa_spi_select(void *self, int sel)
{
       struct mpcsa_spi_softc *sc = device_private(self);

       /* first deselect everything */
       GPIO_SPICS0(at91pio_set);
       GPIO_SPICS1(at91pio_set);
       GPIO_SPICS2(at91pio_set);

       /* then select wanted target */
       switch (sel) {
       case -1:
         break;
       case 0:
         GPIO_SPICS0(at91pio_clear);
         break;
       case 1:
         GPIO_SPICS2(at91pio_clear);
         break;
       case 2:
         GPIO_SPICS2(at91pio_clear);
         break;
       default:
         return EINVAL;
       }

       return 0;
}