text: /*-
   * Copyright (c) 2006 M. Warner Losh <imp@FreeBSD.org>
   *
   * 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>
  __FBSDID("$FreeBSD$");
  
  #include <sys/param.h>
  #include <sys/systm.h>
  #include <sys/malloc.h>
  #include <sys/module.h>
  #include <sys/kernel.h>
  #include <sys/queue.h>
  #include <sys/sysctl.h>
  #include <sys/types.h>
  
  #include <sys/bus.h>
  #include <machine/bus.h>
  #include <sys/rman.h>
  #include <machine/resource.h>
  
  #include <dev/spibus/spibusvar.h>
  #include <dev/spibus/spi.h>
  #include "spibus_if.h"
  
  static int
  spibus_probe(device_t dev)
  {
  
  	device_set_desc(dev, "SPI bus");
  	return (BUS_PROBE_DEFAULT);
  }
  
  static int
  spibus_attach(device_t dev)
  {
  	struct spibus_softc *sc = SPIBUS_SOFTC(dev);
  
  	sc->dev = dev;
  	bus_enumerate_hinted_children(dev);
  	return (bus_generic_attach(dev));
  }
  
  /*
   * Since this is not a self-enumerating bus, and since we always add
   * children in attach, we have to always delete children here.
   */
  static int
  spibus_detach(device_t dev)
  {
  	int err;
  
  	if ((err = bus_generic_detach(dev)) != 0)
  		return (err);
  	device_delete_children(dev);
  
  	return (0);
  }
  
  static int
  spibus_suspend(device_t dev)
  {
  	return (bus_generic_suspend(dev));
  }
  
  static
  int
  spibus_resume(device_t dev)
  {
  	return (bus_generic_resume(dev));
  }
  
  static int
  spibus_print_child(device_t dev, device_t child)
  {
  	struct spibus_ivar *devi = SPIBUS_IVAR(child);
  	int retval = 0;
  
  	retval += bus_print_child_header(dev, child);
  	retval += printf(" at cs %d", devi->cs);
  	retval += printf(" mode %d", devi->mode);
  	retval += bus_print_child_footer(dev, child);
  
  	return (retval);
  }
  
  static void
  spibus_probe_nomatch(device_t bus, device_t child)
  {
  	struct spibus_ivar *devi = SPIBUS_IVAR(child);
  
  	device_printf(bus, "<unknown card> at cs %d mode %d\n", devi->cs,
  	    devi->mode);
  	return;
  }
  
  static int
  spibus_child_location_str(device_t bus, device_t child, char *buf,
      size_t buflen)
  {
  	struct spibus_ivar *devi = SPIBUS_IVAR(child);
  	int cs;
  
  	cs = devi->cs & ~SPIBUS_CS_HIGH; /* trim 'cs high' bit */
  	snprintf(buf, buflen, "bus=%d cs=%d", device_get_unit(bus), cs);
  	return (0);
  }
  
  static int
  spibus_child_pnpinfo_str(device_t bus, device_t child, char *buf,
      size_t buflen)
  {
  	*buf = '\0';
  	return (0);
  }
  
  static int
  spibus_read_ivar(device_t bus, device_t child, int which, uintptr_t *result)
  {
  	struct spibus_ivar *devi = SPIBUS_IVAR(child);
  
  	switch (which) {
  	default:
  		return (EINVAL);
  	case SPIBUS_IVAR_CS:
  		*(uint32_t *)result = devi->cs;
  		break;
  	case SPIBUS_IVAR_MODE:
  		*(uint32_t *)result = devi->mode;
  		break;
  	case SPIBUS_IVAR_CLOCK:
  		*(uint32_t *)result = devi->clock;
  		break;
  	}
  	return (0);
  }
  
  static int
  spibus_write_ivar(device_t bus, device_t child, int which, uintptr_t value)
  {
  	struct spibus_ivar *devi = SPIBUS_IVAR(child);
  
  	if (devi == NULL || device_get_parent(child) != bus)
  		return (EDOOFUS);
  
  	switch (which) {
  	case SPIBUS_IVAR_CLOCK:
  		/* Any non-zero value is allowed for max clock frequency. */
  		if (value == 0)
  			return (EINVAL);
  		devi->clock = (uint32_t)value;
  		break;
  	case SPIBUS_IVAR_CS:
  		 /* Chip select cannot be changed. */
  		return (EINVAL);
  	case SPIBUS_IVAR_MODE:
  		/* Valid SPI modes are 0-3. */
  		if (value > 3)
  			return (EINVAL);
  		devi->mode = (uint32_t)value;
  		break;
  	default:
  		return (EINVAL);
  	}
  
  	return (0);
  }
  
  static device_t
  spibus_add_child(device_t dev, u_int order, const char *name, int unit)
  {
  	device_t child;
  	struct spibus_ivar *devi;
  
  	child = device_add_child_ordered(dev, order, name, unit);
  	if (child == NULL) 
  		return (child);
  	devi = malloc(sizeof(struct spibus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO);
  	if (devi == NULL) {
  		device_delete_child(dev, child);
  		return (0);
  	}
  	device_set_ivars(child, devi);
  	return (child);
  }
  
  static void
  spibus_hinted_child(device_t bus, const char *dname, int dunit)
  {
  	device_t child;
  	struct spibus_ivar *devi;
  
  	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
  	devi = SPIBUS_IVAR(child);
  	devi->mode = SPIBUS_MODE_NONE;
  	resource_int_value(dname, dunit, "clock", &devi->clock);
  	resource_int_value(dname, dunit, "cs", &devi->cs);
  	resource_int_value(dname, dunit, "mode", &devi->mode);
  }
  
  static int
  spibus_transfer_impl(device_t dev, device_t child, struct spi_command *cmd)
  {
  	return (SPIBUS_TRANSFER(device_get_parent(dev), child, cmd));
  }
  
  static device_method_t spibus_methods[] = {
  	/* Device interface */
  	DEVMETHOD(device_probe,		spibus_probe),
  	DEVMETHOD(device_attach,	spibus_attach),
  	DEVMETHOD(device_detach,	spibus_detach),
  	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
  	DEVMETHOD(device_suspend,	spibus_suspend),
  	DEVMETHOD(device_resume,	spibus_resume),
  
  	/* Bus interface */
  	DEVMETHOD(bus_add_child,	spibus_add_child),
  	DEVMETHOD(bus_print_child,	spibus_print_child),
  	DEVMETHOD(bus_probe_nomatch,	spibus_probe_nomatch),
  	DEVMETHOD(bus_read_ivar,	spibus_read_ivar),
  	DEVMETHOD(bus_write_ivar,	spibus_write_ivar),
  	DEVMETHOD(bus_child_pnpinfo_str, spibus_child_pnpinfo_str),
  	DEVMETHOD(bus_child_location_str, spibus_child_location_str),
  	DEVMETHOD(bus_hinted_child,	spibus_hinted_child),
  
  	/* spibus interface */
  	DEVMETHOD(spibus_transfer,	spibus_transfer_impl),
  
  	DEVMETHOD_END
  };
  
  driver_t spibus_driver = {
  	"spibus",
  	spibus_methods,
  	sizeof(struct spibus_softc)
  };
  
  devclass_t	spibus_devclass;
  
  DRIVER_MODULE(spibus, spi, spibus_driver, spibus_devclass, 0, 0);
  MODULE_VERSION(spibus, 1);
  