Update TODO list; SAMv7 XDMAC: Remove and unused global array.

TODO

@@ -2134,6 +2134,24 @@ o Build system
                if you ever decide to control-C out of a make and see that the
                libapps.a file was deleted.
 
+               UPDATE:  This is a potential fix for the second problem in place
+               in apps/Application.mk.  That is include by most (but not all)
+               lower-level Makefiles.  This fix is:
+
+                  --- a/Application.mk
+                  +++ b/Application.mk
+                  @@ -70,6 +70,7 @@ VPATH =
+
+                  all: .built
+                  .PHONY: clean preconfig depend distclean
+                 +.PRECIOUS: $(BIN)
+
+                  $(AOBJS): %$(OBJEXT): %.S
+                         $(call ASSEMBLE, $<, $@)
+
+                It has not yet been confirmed that this fix totally eliminates
+                the issue.
+
 o Other drivers (drivers/)
   ^^^^^^^^^^^^^^^^^^^^^^^^
 

arch/arm/src/samv7/sam_spi.c

@@ -1481,7 +1481,9 @@ static void spi_exchange(struct spi_dev_s *dev, const void *txbuffer,
 {
   struct sam_spics_s *spics = (struct sam_spics_s *)dev;
   struct sam_spidev_s *spi = spi_device(spics);
+#ifdef CONFIG_SAMV7_SPI_VARSELECT
   uint32_t pcs;
+#endif
   uint32_t data;
   uint16_t *rxptr16;
   uint16_t *txptr16;
@@ -1490,9 +1492,11 @@ static void spi_exchange(struct spi_dev_s *dev, const void *txbuffer,
 
   spiinfo("txbuffer=%p rxbuffer=%p nwords=%d\n", txbuffer, rxbuffer, nwords);
 
+#ifdef CONFIG_SAMV7_SPI_VARSELECT
   /* Set up PCS bits */
 
   pcs = spi_cs2pcs(spics) << SPI_TDR_PCS_SHIFT;
+#endif
 
   /* Set up working pointers */
 

arch/arm/src/samv7/sam_xdmac.c

@@ -134,15 +134,6 @@ struct sam_xdmac_s
  * Private Data
  ****************************************************************************/
 
-/* Channel Control (CC) Register field lookups */
-
-static const uint32_t g_chanwidth[3] =
-{
-  XDMACH_CC_DWIDTH_BYTE,
-  XDMACH_CC_DWIDTH_HWORD,
-  XDMACH_CC_DWIDTH_WORD,
-};
-
 /* These tables map peripheral IDs to channels.  A lookup is performed
  * before each DMA transfer in order to map the peripheral IDs to the
  * correct channel.  This must be done because the channel can change with