stm32: Add method for statically configuring pin alternate function.

Works with pins declared normally in mpconfigboard.h, eg. (pin_XX), as well
as (pyb_pin_XX).

Provides new mp_hal_pin_config_alt_static(pin_obj, mode, pull, fn_type)
function declared in pin_static_af.h to allow configuring pin alternate
functions by name at compile time.

ports/stm32/Makefile

@@ -519,6 +519,7 @@ GEN_PINS_SRC = $(BUILD)/pins_$(BOARD).c
 GEN_PINS_HDR = $(HEADER_BUILD)/pins.h
 GEN_PINS_QSTR = $(BUILD)/pins_qstr.h
 GEN_PINS_AF_CONST = $(HEADER_BUILD)/pins_af_const.h
+GEN_PINS_AF_DEFS = $(HEADER_BUILD)/pins_af_defs.h
 GEN_PINS_AF_PY = $(BUILD)/pins_af.py
 
 INSERT_USB_IDS = $(TOP)/tools/insert-usb-ids.py
@@ -551,9 +552,9 @@ main.c: $(GEN_CDCINF_HEADER)
 
 # Use a pattern rule here so that make will only call make-pins.py once to make
 # both pins_$(BOARD).c and pins.h
-$(BUILD)/%_$(BOARD).c $(HEADER_BUILD)/%.h $(HEADER_BUILD)/%_af_const.h $(BUILD)/%_qstr.h: boards/$(BOARD)/%.csv $(MAKE_PINS) $(AF_FILE) $(PREFIX_FILE) | $(HEADER_BUILD)
+$(BUILD)/%_$(BOARD).c $(HEADER_BUILD)/%.h $(HEADER_BUILD)/%_af_const.h $(HEADER_BUILD)/%_af_defs.h $(BUILD)/%_qstr.h: boards/$(BOARD)/%.csv $(MAKE_PINS) $(AF_FILE) $(PREFIX_FILE) | $(HEADER_BUILD)
 	$(ECHO) "GEN $@"
-	$(Q)$(PYTHON) $(MAKE_PINS) --board $(BOARD_PINS) --af $(AF_FILE) --prefix $(PREFIX_FILE) --hdr $(GEN_PINS_HDR) --qstr $(GEN_PINS_QSTR) --af-const $(GEN_PINS_AF_CONST) --af-py $(GEN_PINS_AF_PY) > $(GEN_PINS_SRC)
+	$(Q)$(PYTHON) $(MAKE_PINS) --board $(BOARD_PINS) --af $(AF_FILE) --prefix $(PREFIX_FILE) --hdr $(GEN_PINS_HDR) --qstr $(GEN_PINS_QSTR) --af-const $(GEN_PINS_AF_CONST) --af-defs $(GEN_PINS_AF_DEFS) --af-py $(GEN_PINS_AF_PY) > $(GEN_PINS_SRC)
 
 $(BUILD)/pins_$(BOARD).o: $(BUILD)/pins_$(BOARD).c
 	$(call compile_c)

ports/stm32/boards/make-pins.py

@@ -7,6 +7,7 @@ import argparse
 import sys
 import csv
 
+# Must have matching entries in AF_FN_* enum in ../pin_defs_stm32.h
 SUPPORTED_FN = {
     'TIM'   : ['CH1',  'CH2',  'CH3',  'CH4',
                'CH1N', 'CH2N', 'CH3N', 'CH1_ETR', 'ETR', 'BKIN'],
@@ -291,7 +292,7 @@ class Pins(object):
             if pin.is_board_pin():
                 print('  {{ MP_ROM_QSTR(MP_QSTR_{:s}), MP_ROM_PTR(&pin_{:s}_obj) }},'.format(named_pin.name(),  pin.cpu_pin_name()))
         print('};')
-        print('MP_DEFINE_CONST_DICT(pin_{:s}_pins_locals_dict, pin_{:s}_pins_locals_dict_table);'.format(label, label));
+        print('MP_DEFINE_CONST_DICT(pin_{:s}_pins_locals_dict, pin_{:s}_pins_locals_dict_table);'.format(label, label))
 
     def print(self):
         for named_pin in self.cpu_pins:
@@ -303,7 +304,7 @@ class Pins(object):
         self.print_named('board', self.board_pins)
 
     def print_adc(self, adc_num):
-        print('');
+        print('')
         print('const pin_obj_t * const pin_adc{:d}[] = {{'.format(adc_num))
         for channel in range(17):
             if channel == 16:
@@ -378,9 +379,31 @@ class Pins(object):
                       file=af_const_file)
                 print_conditional_endif(cond_var, file=af_const_file)
 
+    def print_af_defs(self, af_defs_filename):
+        with open(af_defs_filename,  'wt') as af_defs_file:
+
+            STATIC_AF_TOKENS = {}
+            for named_pin in self.board_pins:
+                for af in named_pin.pin().alt_fn:
+                    func = "%s%d" % (af.func, af.fn_num) if af.fn_num else af.func
+                    pin_type = (af.pin_type or "NULL").split('(')[0]
+                    tok = "#define STATIC_AF_%s_%s(pin_obj) ( \\" % (func, pin_type)
+                    if tok not in STATIC_AF_TOKENS:
+                        STATIC_AF_TOKENS[tok] = []
+                    STATIC_AF_TOKENS[tok].append(
+                        '    ((strcmp( #pin_obj , "(&pin_%s_obj)") & strcmp( #pin_obj , "((&pin_%s_obj))")) == 0) ? (%d) : \\' % (
+                            named_pin.pin().cpu_pin_name(), named_pin.pin().cpu_pin_name(), af.idx
+                            )
+                    )
+
+            for tok, pins in STATIC_AF_TOKENS.items():
+                print(tok, file=af_defs_file)
+                print("\n".join(sorted(pins)), file=af_defs_file)
+                print("    (0xffffffffffffffffULL))\n", file=af_defs_file)
+
     def print_af_py(self, af_py_filename):
         with open(af_py_filename,  'wt') as af_py_file:
-            print('PINS_AF = (', file=af_py_file);
+            print('PINS_AF = (', file=af_py_file)
             for named_pin in self.board_pins:
                 print("  ('%s', " % named_pin.name(), end='', file=af_py_file)
                 for af in named_pin.pin().alt_fn:
@@ -414,6 +437,12 @@ def main():
         help="Specifies the filename for the python alternate function mappings.",
         default="build/pins_af.py"
     )
+    parser.add_argument(
+        "--af-defs",
+        dest="af_defs_filename",
+        help="Specifies the filename for the alternate function defines.",
+        default="build/pins_af_defs.h"
+    )
     parser.add_argument(
         "-b", "--board",
         dest="board_filename",
@@ -464,6 +493,7 @@ def main():
     pins.print_qstr(args.qstr_filename)
     pins.print_af_hdr(args.af_const_filename)
     pins.print_af_py(args.af_py_filename)
+    pins.print_af_defs(args.af_defs_filename)
 
 
 if __name__ == "__main__":

ports/stm32/pin_defs_stm32.h

@@ -41,6 +41,7 @@ enum {
   PORT_K,
 };
 
+// Must have matching entries in SUPPORTED_FN in boards/make-pins.py
 enum {
   AF_FN_TIM,
   AF_FN_I2C,

ports/stm32/pin_static_af.h

@@ -0,0 +1,46 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2013, 2014 Damien P. George
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#ifndef MICROPY_INCLUDED_STM32_PIN_STATIC_AF_H
+#define MICROPY_INCLUDED_STM32_PIN_STATIC_AF_H
+
+#include "py/mphal.h"
+#include "genhdr/pins.h"
+#include "genhdr/pins_af_defs.h"
+
+#if 0 // Enable to test if AF's are statically compiled
+#define mp_hal_pin_config_alt_static(pin_obj, mode, pull, fn_type) \
+        mp_hal_pin_config(pin_obj, mode, pull, fn_type(pin_obj)); \
+        _Static_assert(fn_type(pin_obj) != -1, ""); \
+        _Static_assert(__builtin_constant_p(fn_type(pin_obj)) == 1, "")
+
+#else
+
+#define mp_hal_pin_config_alt_static(pin_obj, mode, pull, fn_type) \
+        mp_hal_pin_config(pin_obj, mode, pull, fn_type(pin_obj)) /* Overflow Error => alt func not found */
+
+#endif
+
+#endif // MICROPY_INCLUDED_STM32_PIN_STATIC_AF_H