tegra2: Implement SPI / UART GPIO switch

The Tegra2 Seaboard has the unfortunate feature that SPI and the console
UART are multiplexed on the same pins. We need to switch between one
and the other during SPI and console activity.

This new file implements a switch and keeps track of which peripheral
owns the pins. It also flips over the controlling GPIO as needed

Since we are adding a second file to board/nvidia/common, we create
a proper Makefile there and remove the direct board.o include from
board/nvidia/seaboard/Makefile

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/board/nvidia/common/Makefile b/board/nvidia/common/Makefile
new file mode 100644
index 0000000..3e748fd
--- /dev/null
+++ b/board/nvidia/common/Makefile
@@ -0,0 +1,47 @@
+# Copyright (c) 2011 The Chromium OS Authors.
+# See file CREDITS for list of people who contributed to this
+# project.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation; either version 2 of
+# the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+# MA 02111-1307 USA
+
+include $(TOPDIR)/config.mk
+
+ifneq ($(OBJTREE),$(SRCTREE))
+$(shell mkdir -p $(obj)board/$(VENDOR)/common)
+endif
+
+LIB	= $(obj)lib$(VENDOR).o
+
+COBJS-y += board.o
+COBJS-$(CONFIG_SPI_UART_SWITCH) += uart-spi-switch.o
+
+COBJS	:= $(COBJS-y)
+SRCS	:= $(SOBJS:.o=.S) $(COBJS:.o=.c)
+OBJS	:= $(addprefix $(obj),$(COBJS))
+SOBJS	:= $(addprefix $(obj),$(SOBJS))
+
+all:	$(LIB)
+
+$(LIB):	$(obj).depend $(OBJS) $(SOBJS)
+	$(call cmd_link_o_target, $(OBJS) $(SOBJS))
+
+#########################################################################
+# This is for $(obj).depend target
+include $(SRCTREE)/rules.mk
+
+sinclude $(obj).depend
+
+#########################################################################