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/***************************************************************************

    device.c

    Device interface functions.

****************************************************************************

    Copyright Aaron Giles
    All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are
    met:

        * Redistributions of source code must retain the above copyright
          notice, this list of conditions and the following disclaimer.
        * 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.
        * Neither the name 'MAME' nor the names of its contributors may be
          used to endorse or promote products derived from this software
          without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY AARON GILES ''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 AARON GILES 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 "emu.h"
#include "debug/debugcpu.h"



//**************************************************************************
//  CONSTANTS
//**************************************************************************

#define TEMP_STRING_POOL_ENTRIES		16
#define MAX_STRING_LENGTH				256



//**************************************************************************
//  GLOBAL VARIABLES
//**************************************************************************

static char temp_string_pool[TEMP_STRING_POOL_ENTRIES][MAX_STRING_LENGTH];
static int temp_string_pool_index;



//**************************************************************************
//  INLINE FUNCTIONS
//**************************************************************************

//-------------------------------------------------
//  get_temp_string_buffer - return a pointer to
//  a temporary string buffer
//-------------------------------------------------

char *get_temp_string_buffer(void)
{
	char *string = &temp_string_pool[temp_string_pool_index++ % TEMP_STRING_POOL_ENTRIES][0];
	string[0] = 0;
	return string;
}


resource_pool &machine_get_pool(running_machine &machine)
{
	// temporary to get around include dependencies, until CPUs
	// get a proper device class
	return machine.respool();
}



//**************************************************************************
//  LIVE DEVICE MANAGEMENT
//**************************************************************************

//-------------------------------------------------
//  device_t - constructor for a new
//  running device; initial state is derived
//  from the provided config
//-------------------------------------------------

device_t::device_t(const machine_config &mconfig, device_type type, const char *name, const char *tag, device_t *owner, UINT32 clock)
	: m_type(type),
	  m_name(name),
	  m_owner(owner),
	  m_next(NULL),

	  m_interface_list(NULL),
	  m_execute(NULL),
	  m_memory(NULL),
	  m_state(NULL),

	  m_configured_clock(clock),
	  m_unscaled_clock(clock),
	  m_clock(clock),
	  m_clock_scale(1.0),
	  m_attoseconds_per_clock((clock == 0) ? 0 : HZ_TO_ATTOSECONDS(clock)),

	  m_debug(NULL),
	  m_region(NULL),
	  m_machine_config(mconfig),
	  m_static_config(NULL),
	  m_input_defaults(NULL),

	  m_machine(NULL),
	  m_save(NULL),
	  m_basetag(tag),
	  m_config_complete(false),
	  m_started(false),
	  m_auto_finder_list(NULL)
{
	if (owner != NULL)
		m_tag.cpy((owner->owner() == NULL) ? "" : owner->tag()).cat(":").cat(tag);
	else
		m_tag.cpy(":");
	static_set_clock(*this, clock);
}


device_t::device_t(const machine_config &mconfig, device_type type, const char *name, const char *shortname, const char *tag, device_t *owner, UINT32 clock)
	: m_type(type),
	  m_name(name),
	  m_shortname(shortname),
	  m_searchpath(shortname),
	  m_owner(owner),
	  m_next(NULL),

	  m_interface_list(NULL),
	  m_execute(NULL),
	  m_memory(NULL),
	  m_state(NULL),

	  m_configured_clock(clock),
	  m_unscaled_clock(clock),
	  m_clock(clock),
	  m_clock_scale(1.0),
	  m_attoseconds_per_clock((clock == 0) ? 0 : HZ_TO_ATTOSECONDS(clock)),

	  m_debug(NULL),
	  m_region(NULL),
	  m_machine_config(mconfig),
	  m_static_config(NULL),
	  m_input_defaults(NULL),

	  m_machine(NULL),
	  m_save(NULL),
	  m_basetag(tag),
	  m_config_complete(false),
	  m_started(false),
	  m_auto_finder_list(NULL)
{
	if (owner != NULL)
		m_tag.cpy((owner->owner() == NULL) ? "" : owner->tag()).cat(":").cat(tag);
	else
		m_tag.cpy(":");
	static_set_clock(*this, clock);
}


//-------------------------------------------------
//  ~device_t - destructor for a device_t
//-------------------------------------------------

device_t::~device_t()
{
}


//-------------------------------------------------
//  memregion - return a pointer to the region
//  info for a given region
//-------------------------------------------------

memory_region *device_t::memregion(const char *_tag) const
{
	// safety first
	if (this == NULL)
		return NULL;

	// build a fully-qualified name and look it up
	astring fullpath;
	return machine().memory().region(subtag(fullpath, _tag));
}


//-------------------------------------------------
//  memshare - return a pointer to the memory share
//  info for a given share
//-------------------------------------------------

memory_share *device_t::memshare(const char *_tag) const
{
	// safety first
	if (this == NULL)
		return NULL;

	// build a fully-qualified name and look it up
	astring fullpath;
	return machine().memory().shared(subtag(fullpath, _tag));
}


//-------------------------------------------------
//  membank - return a pointer to the memory
//  bank info for a given bank
//-------------------------------------------------

memory_bank *device_t::membank(const char *_tag) const
{
	// safety first
	if (this == NULL)
		return NULL;

	// build a fully-qualified name and look it up
	astring fullpath;
	return machine().memory().bank(subtag(fullpath, _tag));
}


//-------------------------------------------------
//  ioport - return a pointer to the I/O port
//  object for a given port name
//-------------------------------------------------

ioport_port *device_t::ioport(const char *tag) const
{
	// safety first
	if (this == NULL)
		return NULL;

	// build a fully-qualified name and look it up
	astring fullpath;
	return machine().ioport().port(subtag(fullpath, tag));
}


//-------------------------------------------------
//  static_set_clock - set/change the clock on
//  a device
//-------------------------------------------------

void device_t::static_set_clock(device_t &device, UINT32 clock)
{
	// derive the clock from our owner if requested
	if ((clock & 0xff000000) == 0xff000000)
	{
		assert(device.m_owner != NULL);
		clock = device.m_owner->m_configured_clock * ((clock >> 12) & 0xfff) / ((clock >> 0) & 0xfff);
	}

	device.m_clock = device.m_unscaled_clock = device.m_configured_clock = clock;
	device.m_attoseconds_per_clock = (clock == 0) ? 0 : HZ_TO_ATTOSECONDS(clock);
}


//-------------------------------------------------
//  config_complete - called when the
//  configuration of a device is complete
//-------------------------------------------------

void device_t::config_complete()
{
	// first notify the interfaces
	for (device_interface *intf = m_interface_list; intf != NULL; intf = intf->interface_next())
		intf->interface_config_complete();

	// then notify the device itself
	device_config_complete();

	// then mark ourselves complete
	m_config_complete = true;
}


//-------------------------------------------------
//  validity_check - validate a device after the
//  configuration has been constructed
//-------------------------------------------------

void device_t::validity_check(validity_checker &valid) const
{
	// validate via the interfaces
	for (device_interface *intf = m_interface_list; intf != NULL; intf = intf->interface_next())
		intf->interface_validity_check(valid);

	// let the device itself validate
	device_validity_check(valid);
}


//-------------------------------------------------
//  reset - reset a device
//-------------------------------------------------

void device_t::reset()
{
	// let the interfaces do their pre-work
	for (device_interface *intf = m_interface_list; intf != NULL; intf = intf->interface_next())
		intf->interface_pre_reset();

	// reset the device
	device_reset();

	// reset all child devices
	for (device_t *child = m_subdevice_list.first(); child != NULL; child = child->next())
		child->reset();

	// now allow for some post-child reset action
	device_reset_after_children();

	// let the interfaces do their post-work
	for (device_interface *intf = m_interface_list; intf != NULL; intf = intf->interface_next())
		intf->interface_post_reset();
}


//-------------------------------------------------
//  set_unscaled_clock - sets the given device's
//  unscaled clock
//-------------------------------------------------

void device_t::set_unscaled_clock(UINT32 clock)
{
	m_unscaled_clock = clock;
	m_clock = m_unscaled_clock * m_clock_scale;
	m_attoseconds_per_clock = HZ_TO_ATTOSECONDS(m_clock);
	notify_clock_changed();
}


//-------------------------------------------------
//  set_clock_scale - sets a scale factor for the
//  device's clock
//-------------------------------------------------

void device_t::set_clock_scale(double clockscale)
{
	m_clock_scale = clockscale;
	m_clock = m_unscaled_clock * m_clock_scale;
	m_attoseconds_per_clock = HZ_TO_ATTOSECONDS(m_clock);
	notify_clock_changed();
}


//-------------------------------------------------
//  clocks_to_attotime - converts a number of
//  clock ticks to an attotime
//-------------------------------------------------

attotime device_t::clocks_to_attotime(UINT64 numclocks) const
{
	if (numclocks < m_clock)
		return attotime(0, numclocks * m_attoseconds_per_clock);
	else
	{
		UINT32 remainder;
		UINT32 quotient = divu_64x32_rem(numclocks, m_clock, &remainder);
		return attotime(quotient, (UINT64)remainder * (UINT64)m_attoseconds_per_clock);
	}
}


//-------------------------------------------------
//  attotime_to_clocks - converts a duration as
//  attotime to CPU clock ticks
//-------------------------------------------------

UINT64 device_t::attotime_to_clocks(attotime duration) const
{
	return mulu_32x32(duration.seconds, m_clock) + (UINT64)duration.attoseconds / (UINT64)m_attoseconds_per_clock;
}


//-------------------------------------------------
//  timer_alloc - allocate a timer for our device
//  callback
//-------------------------------------------------

emu_timer *device_t::timer_alloc(device_timer_id id, void *ptr)
{
	return machine().scheduler().timer_alloc(*this, id, ptr);
}


//-------------------------------------------------
//  timer_set - set a temporary timer that will
//  call our device callback
//-------------------------------------------------

void device_t::timer_set(attotime duration, device_timer_id id, int param, void *ptr)
{
	machine().scheduler().timer_set(duration, *this, id, param, ptr);
}


//-------------------------------------------------
//  set_machine - notify that the machine now
//  exists
//-------------------------------------------------

void device_t::set_machine(running_machine &machine)
{
	m_machine = &machine;
	m_save = &machine.save();
}


//-------------------------------------------------
//  start - start a device
//-------------------------------------------------

void device_t::start()
{
	// populate the machine and the region field
	m_region = machine().root_device().memregion(tag());

	// find all the registered devices
	bool allfound = true;
	for (finder_base *autodev = m_auto_finder_list; autodev != NULL; autodev = autodev->m_next)
		allfound &= autodev->findit();
	if (!allfound)
		throw emu_fatalerror("Missing some required objects, unable to proceed");

	// let the interfaces do their pre-work
	for (device_interface *intf = m_interface_list; intf != NULL; intf = intf->interface_next())
		intf->interface_pre_start();

	// remember the number of state registrations
	int state_registrations = machine().save().registration_count();

	// start the device
	device_start();

	// complain if nothing was registered by the device
	state_registrations = machine().save().registration_count() - state_registrations;
	device_execute_interface *exec;
	device_sound_interface *sound;
	if (state_registrations == 0 && (interface(exec) || interface(sound)) && type() != SPEAKER)
	{
		logerror("Device '%s' did not register any state to save!\n", tag());
		if ((machine().system().flags & GAME_SUPPORTS_SAVE) != 0)
			fatalerror("Device '%s' did not register any state to save!\n", tag());
	}

	// let the interfaces do their post-work
	for (device_interface *intf = m_interface_list; intf != NULL; intf = intf->interface_next())
		intf->interface_post_start();

	// force an update of the clock
	notify_clock_changed();

	// if we're debugging, create a device_debug object
	if ((machine().debug_flags & DEBUG_FLAG_ENABLED) != 0)
	{
		m_debug = auto_alloc(machine(), device_debug(*this));
		debug_setup();
	}

	// register our save states
	save_item(NAME(m_clock));
	save_item(NAME(m_unscaled_clock));
	save_item(NAME(m_clock_scale));

	// we're now officially started
	m_started = true;
}


//-------------------------------------------------
//  stop - stop a device
//-------------------------------------------------

void device_t::stop()
{
	// let the interfaces do their pre-work
	for (device_interface *intf = m_interface_list; intf != NULL; intf = intf->interface_next())
		intf->interface_pre_stop();

	// stop the device
	device_stop();

	// let the interfaces do their post-work
	for (device_interface *intf = m_interface_list; intf != NULL; intf = intf->interface_next())
		intf->interface_post_stop();

	// free any debugging info
	auto_free(machine(), m_debug);

	// we're now officially stopped, and the machine is off-limits
	m_started = false;
	m_machine = NULL;
}


//-------------------------------------------------
//  debug_setup - set up for debugging
//-------------------------------------------------

void device_t::debug_setup()
{
	// notify the interface
	for (device_interface *intf = m_interface_list; intf != NULL; intf = intf->interface_next())
		intf->interface_debug_setup();

	// notify the device
	device_debug_setup();
}


//-------------------------------------------------
//  pre_save - tell the device and its interfaces
//  that we are about to save
//-------------------------------------------------

void device_t::pre_save()
{
	// notify the interface
	for (device_interface *intf = m_interface_list; intf != NULL; intf = intf->interface_next())
		intf->interface_pre_save();

	// notify the device
	device_pre_save();
}


//-------------------------------------------------
//  post_load - tell the device and its interfaces
//  that we just completed a load
//-------------------------------------------------

void device_t::post_load()
{
	// notify the interface
	for (device_interface *intf = m_interface_list; intf != NULL; intf = intf->interface_next())
		intf->interface_post_load();

	// notify the device
	device_post_load();
}


//-------------------------------------------------
//  notify_clock_changed - notify all interfaces
//  that the clock has changed
//-------------------------------------------------

void device_t::notify_clock_changed()
{
	// first notify interfaces
	for (device_interface *intf = m_interface_list; intf != NULL; intf = intf->interface_next())
		intf->interface_clock_changed();

	// then notify the device
	device_clock_changed();
}


//-------------------------------------------------
//  device_config_complete - perform any
//  operations now that the configuration is
//  complete
//-------------------------------------------------

void device_t::device_config_complete()
{
	// do nothing by default
}


//-------------------------------------------------
//  device_validity_check - validate a device after
//  the configuration has been constructed
//-------------------------------------------------

void device_t::device_validity_check(validity_checker &valid) const
{
	// do nothing by default
}


//-------------------------------------------------
//  rom_region - return a pointer to the implicit
//  rom region description for this device
//-------------------------------------------------

const rom_entry *device_t::device_rom_region() const
{
	// none by default
	return NULL;
}


//-------------------------------------------------
//  machine_config - return a pointer to a machine
//  config constructor describing sub-devices for
//  this device
//-------------------------------------------------

machine_config_constructor device_t::device_mconfig_additions() const
{
	// none by default
	return NULL;
}


//-------------------------------------------------
//  input_ports - return a pointer to the implicit
//  input ports description for this device
//-------------------------------------------------

ioport_constructor device_t::device_input_ports() const
{
	// none by default
	return NULL;
}


//-------------------------------------------------
//  device_reset - actually handle resetting of
//  a device; designed to be overriden by the
//  actual device implementation
//-------------------------------------------------

void device_t::device_reset()
{
	// do nothing by default
}


//-------------------------------------------------
//  device_reset_after_children - hook to do
//  reset logic that must happen after the children
//  are reset; designed to be overriden by the
//  actual device implementation
//-------------------------------------------------

void device_t::device_reset_after_children()
{
	// do nothing by default
}


//-------------------------------------------------
//  device_stop - clean up anything that needs to
//  happen before the running_machine goes away
//-------------------------------------------------

void device_t::device_stop()
{
	// do nothing by default
}


//-------------------------------------------------
//  device_pre_save - called prior to saving the
//  state, so that registered variables can be
//  properly normalized
//-------------------------------------------------

void device_t::device_pre_save()
{
	// do nothing by default
}


//-------------------------------------------------
//  device_post_load - called after the loading a
//  saved state, so that registered variables can
//  be expaneded as necessary
//-------------------------------------------------

void device_t::device_post_load()
{
	// do nothing by default
}


//-------------------------------------------------
//  device_clock_changed - called when the
//  device clock is altered in any way; designed
//  to be overridden by the actual device
//  implementation
//-------------------------------------------------

void device_t::device_clock_changed()
{
	// do nothing by default
}


//-------------------------------------------------
//  device_debug_setup - called when the debugger
//  is active to allow for device-specific setup
//-------------------------------------------------

void device_t::device_debug_setup()
{
	// do nothing by default
}


//-------------------------------------------------
//  device_timer - called whenever a device timer
//  fires
//-------------------------------------------------

void device_t::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr)
{
	// do nothing by default
}


//-------------------------------------------------
//  subdevice_slow - perform a slow name lookup,
//  caching the results
//-------------------------------------------------

device_t *device_t::subdevice_slow(const char *tag) const
{
	// resolve the full path
	astring fulltag;
	subtag(fulltag, tag);

	// we presume the result is a rooted path; also doubled colons mess up our
	// tree walk, so catch them early
	assert(fulltag[0] == ':');
	assert(fulltag.find("::") == -1);

	// walk the device list to the final path
	device_t *curdevice = &mconfig().root_device();
	if (fulltag.len() > 1)
		for (int start = 1, end = fulltag.chr(start, ':'); start != 0 && curdevice != NULL; start = end + 1, end = fulltag.chr(start, ':'))
		{
			astring part(fulltag, start, (end == -1) ? -1 : end - start);
			for (curdevice = curdevice->m_subdevice_list.first(); curdevice != NULL; curdevice = curdevice->next())
				if (part == curdevice->m_basetag)
					break;
		}

	// if we got a match, add to the fast map
	if (curdevice != NULL)
		m_device_map.add(tag, curdevice);
	return curdevice;
}


//-------------------------------------------------
//  subtag - create a fully resolved path relative
//  to our device based on the provided tag
//-------------------------------------------------

astring &device_t::subtag(astring &result, const char *tag) const
{
	// if the tag begins with a colon, ignore our path and start from the root
	if (*tag == ':')
	{
		tag++;
		result.cpy(":");
	}

	// otherwise, start with our path
	else
	{
		result.cpy(m_tag);
		if (result != ":")
			result.cat(":");
	}

	// iterate over the tag, look for special path characters to resolve
	const char *caret;
	while ((caret = strchr(tag, '^')) != NULL)
	{
		// copy everything up to there
		result.cat(tag, caret - tag);
		tag = caret + 1;

		// strip trailing colons
		int len = result.len();
		while (result[--len] == ':')
			result.substr(0, len);

		// remove the last path part, leaving the last colon
		if (result != ":")
		{
			int lastcolon = result.rchr(0, ':');
			if (lastcolon != -1)
				result.substr(0, lastcolon + 1);
		}
	}

	// copy everything else
	result.cat(tag);

	// strip trailing colons up to the root
	int len = result.len();
	while (len > 1 && result[--len] == ':')
		result.substr(0, len);
	return result;
}


//-------------------------------------------------
//  add_subdevice - create a new device and add it
//  as a subdevice
//-------------------------------------------------

device_t *device_t::add_subdevice(device_type type, const char *tag, UINT32 clock)
{
	// allocate the device and append to our list
	device_t *device = (*type)(mconfig(), tag, this, clock);
	m_subdevice_list.append(*device);

	// apply any machine configuration owned by the device now
	machine_config_constructor additions = device->machine_config_additions();
	if (additions != NULL)
		(*additions)(const_cast<machine_config &>(mconfig()), device);
	return device;
}


//-------------------------------------------------
//  add_subdevice - create a new device and use it
//  to replace an existing subdevice
//-------------------------------------------------

device_t *device_t::replace_subdevice(device_t &old, device_type type, const char *tag, UINT32 clock)
{
	// iterate over all devices and remove any references to the old device
	device_iterator iter(mconfig().root_device());
	for (device_t *scan = iter.first(); scan != NULL; scan = iter.next())
		scan->m_device_map.remove(&old);

	// create a new device, and substitute it for the old one
	device_t *device = (*type)(mconfig(), tag, this, clock);
	m_subdevice_list.replace_and_remove(*device, old);

	// apply any machine configuration owned by the device now
	machine_config_constructor additions = device->machine_config_additions();
	if (additions != NULL)
		(*additions)(const_cast<machine_config &>(mconfig()), device);
	return device;
}


//-------------------------------------------------
//  remove_subdevice - remove a given subdevice
//-------------------------------------------------

void device_t::remove_subdevice(device_t &device)
{
	// iterate over all devices and remove any references
	device_iterator iter(mconfig().root_device());
	for (device_t *scan = iter.first(); scan != NULL; scan = iter.next())
		scan->m_device_map.remove(&device);

	// remove from our list
	m_subdevice_list.remove(device);
}


//-------------------------------------------------
//  register_auto_finder - add a new item to the
//  list of stuff to find after we go live
//-------------------------------------------------

device_t::finder_base *device_t::register_auto_finder(finder_base &autodev)
{
	// add to this list
	finder_base *old = m_auto_finder_list;
	m_auto_finder_list = &autodev;
	return old;
}


//-------------------------------------------------
//  finder_base - constructor
//-------------------------------------------------

device_t::finder_base::finder_base(device_t &base, const char *tag)
	: m_next(base.register_auto_finder(*this)),
	  m_base(base),
	  m_tag(tag)
{
}


//-------------------------------------------------
//  ~finder_base - destructor
//-------------------------------------------------

device_t::finder_base::~finder_base()
{
}


//-------------------------------------------------
//  find_memory - find memory
//-------------------------------------------------

void *device_t::finder_base::find_memory(UINT8 width, size_t &bytes, bool required)
{
	// look up the share and return NULL if not found
	memory_share *share = m_base.memshare(m_tag);
	if (share == NULL)
		return NULL;

	// check the width and warn if not correct
	if (width != 0 && share->width() != width)
	{
		if (required)
			mame_printf_warning("Shared ptr '%s' found but is width %d, not %d as requested\n", m_tag, share->width(), width);
		return NULL;
	}

	// return results
	bytes = share->bytes();
	return share->ptr();
}


//-------------------------------------------------
//  report_missing - report missing objects and
//  return true if it's ok
//-------------------------------------------------

bool device_t::finder_base::report_missing(bool found, const char *objname, bool required)
{
	// just pass through in the found case
	if (found)
		return true;

	// otherwise, report
	if (required)
		mame_printf_error("Required %s '%s' not found\n", objname, m_tag);
	else
		mame_printf_verbose("Optional %s '%s' not found\n", objname, m_tag);
	return !required;
}


//**************************************************************************
//  LIVE DEVICE INTERFACES
//**************************************************************************

//-------------------------------------------------
//  device_interface - constructor
//-------------------------------------------------

device_interface::device_interface(device_t &device)
	: m_interface_next(NULL),
	  m_device(device)
{
	device_interface **tailptr;
	for (tailptr = &device.m_interface_list; *tailptr != NULL; tailptr = &(*tailptr)->m_interface_next) ;
	*tailptr = this;
}


//-------------------------------------------------
//  ~device_interface - destructor
//-------------------------------------------------

device_interface::~device_interface()
{
}


//-------------------------------------------------
//  interface_config_complete - perform any
//  operations now that the configuration is
//  complete
//-------------------------------------------------

void device_interface::interface_config_complete()
{
	// do nothing by default
}


//-------------------------------------------------
//  interface_validity_check - default validation
//  for a device after the configuration has been
//  constructed
//-------------------------------------------------

void device_interface::interface_validity_check(validity_checker &valid) const
{
}


//-------------------------------------------------
//  interface_pre_start - called before the
//  device's own start function
//-------------------------------------------------

void device_interface::interface_pre_start()
{
	// do nothing by default
}


//-------------------------------------------------
//  interface_post_start - called after the
//  device's own start function
//-------------------------------------------------

void device_interface::interface_post_start()
{
	// do nothing by default
}


//-------------------------------------------------
//  interface_pre_reset - called before the
//  device's own reset function
//-------------------------------------------------

void device_interface::interface_pre_reset()
{
	// do nothing by default
}


//-------------------------------------------------
//  interface_post_reset - called after the
//  device's own reset function
//-------------------------------------------------

void device_interface::interface_post_reset()
{
	// do nothing by default
}


//-------------------------------------------------
//  interface_pre_stop - called before the
//  device's own stop function
//-------------------------------------------------

void device_interface::interface_pre_stop()
{
	// do nothing by default
}


//-------------------------------------------------
//  interface_post_stop - called after the
//  device's own stop function
//-------------------------------------------------

void device_interface::interface_post_stop()
{
	// do nothing by default
}


//-------------------------------------------------
//  interface_pre_save - called prior to saving the
//  state, so that registered variables can be
//  properly normalized
//-------------------------------------------------

void device_interface::interface_pre_save()
{
	// do nothing by default
}


//-------------------------------------------------
//  interface_post_load - called after the loading a
//  saved state, so that registered variables can
//  be expaneded as necessary
//-------------------------------------------------

void device_interface::interface_post_load()
{
	// do nothing by default
}


//-------------------------------------------------
//  interface_clock_changed - called when the
//  device clock is altered in any way; designed
//  to be overridden by the actual device
//  implementation
//-------------------------------------------------

void device_interface::interface_clock_changed()
{
	// do nothing by default
}


//-------------------------------------------------
//  interface_debug_setup - called to allow
//  interfaces to set up any debugging for this
//  device
//-------------------------------------------------

void device_interface::interface_debug_setup()
{
	// do nothing by default
}