tc: make tc_bus_type const

Since commit d492cc2573a0 ("driver core: device.h: make struct
bus_type a const *"), the driver core can properly handle constant
struct bus_type, move the tc_bus_type variable to be a constant
structure as well, placing it into read-only memory which can not be
modified at runtime.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Acked-by: Maciej W. Rozycki <macro@orcam.me.uk>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

tc: Make tc_match_device() static

Unlike its PCI counterpart, tc_match_device() was never used outside
the TURBOchannel bus code.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: Maciej W . Rozycki <macro@linux-mips.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org

[TC] MIPS: TURBOchannel update to the driver model

This is a set of changes to convert support for the TURBOchannel bus to the
driver model. It implements the usual set of calls similar to what other bus
drivers have: tc_register_driver(), tc_unregister_driver(), etc. All the
platform-specific bits have been removed and headers from asm-mips/dec/ have
been merged into linux/tc.h, which should be included by drivers.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>