Cleaned out libmaple.h; this had wide-ranging implications.

Many of the #defines in libmaple.h were board-specific, not
MCU-specific.  Most of these were only used by code under
libmaple/usb/.  These were moved into usb_config.h, and are clearly
marked as being terrible hacks.  I'm going to treat the USB stack as a
black box that we'll deal with later.

Further, instead of having a variety of #defines like "How many USARTS
do I have?", we decide that based on the density of the chip.  This is
determined by testing for STM32_MEDIUM_DENSITY or STM32_HIGH_DENSITY
defines.  libmaple currently doesn't support low-density chips, so
that suffices.  The Makefile will set these automatically based on the
MCU.

Other offending #defines are ERROR_LED_PORT and ERROR_LED_PIN; these
were made optional, but they're set in the Makefile as a hack to keep
things working.

1 files changed, 7 insertions, 5 deletions

diff --git a/libmaple/bkp.c b/libmaple/bkp.c
index ac9aeae..ed107d8 100644
--- a/libmaple/bkp.c
+++ b/libmaple/bkp.c
@@ -69,7 +69,8 @@ void bkp_disable_writes(void) {
 
 /**
  * Read a value from given backup data register.
- * @param reg Data register to read, from 1 to NR_BKP_REGS (10 on Maple).
+ * @param reg Data register to read, from 1 to BKP_NR_DATA_REGS (10 on
+ *            medium-density devices, 42 on high-density devices).
  */
 uint16 bkp_read(uint8 reg) {
     __io uint32* dr = data_register(reg);
@@ -85,7 +86,8 @@ uint16 bkp_read(uint8 reg) {
  *
  * Write access to backup registers must be enabled.
  *
- * @param reg Data register to write, from 1 to NR_BKP_REGS (10 on Maple).
+ * @param reg Data register to write, from 1 to BKP_NR_DATA_REGS (10
+ *            on medium-density devices, 42 on high-density devices).
  * @param val Value to write into the register.
  * @see bkp_enable_writes()
  */
@@ -101,16 +103,16 @@ void bkp_write(uint8 reg, uint16 val) {
 /*
  * Data register memory layout is not contiguous. It's split up from
  * 1--NR_LOW_DRS, beginning at BKP_BASE->DR1, through to
- * (NR_LOW_DRS+1)--NR_BKP_REGS, beginning at BKP_BASE->DR10.
+ * (NR_LOW_DRS+1)--BKP_NR_DATA_REGS, beginning at BKP_BASE->DR11.
  */
 #define NR_LOW_DRS 10
 
 static inline __io uint32* data_register(uint8 reg) {
-    if (reg < 1 || reg > NR_BKP_REGS) {
+    if (reg < 1 || reg > BKP_NR_DATA_REGS) {
         return 0;
     }
 
-#if NR_BKP_REGS == NR_LOW_DRS
+#if BKP_NR_DATA_REGS == NR_LOW_DRS
     return (uint32*)BKP_BASE + reg;
 #else
     if (reg <= NR_LOW_DRS) {