7 files changed, 18 insertions, 21 deletions
diff --git a/builddefs/build_keyboard.mk b/builddefs/build_keyboard.mk
index 37466cbbe5..8999ac80ad 100644
--- a/builddefs/build_keyboard.mk
+++ b/builddefs/build_keyboard.mk
@@ -180,13 +180,6 @@ generated-files: $(KEYMAP_OUTPUT)/src/config.h $(KEYMAP_OUTPUT)/src/keymap.c
 
 endif
 
-# PLATFORM_KEY should be detected in info.json via key 'processor' (or rules.mk 'MCU')
-ifeq ($(PLATFORM_KEY),)
-    $(call CATASTROPHIC_ERROR,Platform not defined)
-endif
-PLATFORM=$(shell echo $(PLATFORM_KEY) | tr '[:lower:]' '[:upper:]')
-
-
 include $(BUILDDEFS_PATH)/converters.mk
 
 include $(BUILDDEFS_PATH)/mcu_selection.mk
@@ -264,6 +257,24 @@ ifneq ("$(wildcard $(KEYBOARD_PATH_5)/$(KEYBOARD_FOLDER_5).h)","")
     FOUND_KEYBOARD_H = $(KEYBOARD_FOLDER_5).h
 endif
 
+# Determine and set parameters based on the keyboard's processor family.
+# We can assume a ChibiOS target When MCU_FAMILY is defined since it's
+# not used for LUFA
+ifdef MCU_FAMILY
+    PLATFORM=CHIBIOS
+    PLATFORM_KEY=chibios
+    FIRMWARE_FORMAT?=bin
+    OPT_DEFS += -DMCU_$(MCU_FAMILY)
+else ifdef ARM_ATSAM
+    PLATFORM=ARM_ATSAM
+    PLATFORM_KEY=arm_atsam
+    FIRMWARE_FORMAT=bin
+else
+    PLATFORM=AVR
+    PLATFORM_KEY=avr
+    FIRMWARE_FORMAT?=hex
+endif
+
 # Find all of the config.h files and add them to our CONFIG_H define.
 CONFIG_H :=
 ifneq ("$(wildcard $(KEYBOARD_PATH_5)/config.h)","")
diff --git a/data/mappings/info_rules.hjson b/data/mappings/info_rules.hjson
index c409da04c6..b020d0c813 100644
--- a/data/mappings/info_rules.hjson
+++ b/data/mappings/info_rules.hjson
@@ -38,8 +38,6 @@
     "PS2_MOUSE_ENABLE": {"info_key": "ps2.mouse_enabled", "value_type": "bool"},
     "PS2_DRIVER": {"info_key": "ps2.driver"},
 
-    "PLATFORM_KEY": {"info_key": "platform_key", "to_json": false},
-
     // Items we want flagged in lint
     "CTPC": {"info_key": "_deprecated.ctpc", "deprecated": true, "replace_with": "CONVERT_TO=proton_c"},
     "CONVERT_TO_PROTON_C": {"info_key": "_deprecated.ctpc", "deprecated": true, "replace_with": "CONVERT_TO=proton_c"},
diff --git a/lib/python/qmk/info.py b/lib/python/qmk/info.py
index 789d05850c..af3b0f3091 100644
--- a/lib/python/qmk/info.py
+++ b/lib/python/qmk/info.py
@@ -751,7 +751,6 @@ def arm_processor_rules(info_data, rules):
     """
     info_data['processor_type'] = 'arm'
     info_data['protocol'] = 'ChibiOS'
-    info_data['platform_key'] = 'chibios'
 
     if 'STM32' in info_data['processor']:
         info_data['platform'] = 'STM32'
@@ -759,7 +758,6 @@ def arm_processor_rules(info_data, rules):
         info_data['platform'] = rules['MCU_SERIES']
     elif 'ARM_ATSAM' in rules:
         info_data['platform'] = 'ARM_ATSAM'
-        info_data['platform_key'] = 'arm_atsam'
 
     return info_data
 
@@ -769,7 +767,6 @@ def avr_processor_rules(info_data, rules):
     """
     info_data['processor_type'] = 'avr'
     info_data['platform'] = rules['ARCH'] if 'ARCH' in rules else 'unknown'
-    info_data['platform_key'] = 'avr'
     info_data['protocol'] = 'V-USB' if info_data['processor'] in VUSB_PROCESSORS else 'LUFA'
 
     # FIXME(fauxpark/anyone): Eventually we should detect the protocol by looking at PROTOCOL inherited from mcu_selection.mk:
diff --git a/platforms/arm_atsam/bootloader.mk b/platforms/arm_atsam/bootloader.mk
index 7e503bdca9..1ec42edeb6 100644
--- a/platforms/arm_atsam/bootloader.mk
+++ b/platforms/arm_atsam/bootloader.mk
@@ -27,8 +27,6 @@
 # the respective file under `platforms/<PLATFORM>/bootloaders/custom.c` to see
 # which functions may be overridden.
 
-FIRMWARE_FORMAT?=bin
-
 ifeq ($(strip $(BOOTLOADER)), custom)
     OPT_DEFS += -DBOOTLOADER_CUSTOM
     BOOTLOADER_TYPE = custom
diff --git a/platforms/avr/bootloader.mk b/platforms/avr/bootloader.mk
index 36e3fd83db..63fe635d96 100644
--- a/platforms/avr/bootloader.mk
+++ b/platforms/avr/bootloader.mk
@@ -37,8 +37,6 @@
 # BOOTLOADER_SIZE can still be defined manually, but it's recommended
 # you add any possible configuration to this list
 
-FIRMWARE_FORMAT?=hex
-
 ifeq ($(strip $(BOOTLOADER)), custom)
     OPT_DEFS += -DBOOTLOADER_CUSTOM
     BOOTLOADER_TYPE = custom
diff --git a/platforms/chibios/bootloader.mk b/platforms/chibios/bootloader.mk
index 546faf2d27..0568d35321 100644
--- a/platforms/chibios/bootloader.mk
+++ b/platforms/chibios/bootloader.mk
@@ -36,8 +36,6 @@
 # the respective file under `platforms/<PLATFORM>/bootloaders/custom.c` to see
 # which functions may be overridden.
 
-FIRMWARE_FORMAT?=bin
-
 ifeq ($(strip $(BOOTLOADER)), custom)
     OPT_DEFS += -DBOOTLOADER_CUSTOM
     BOOTLOADER_TYPE = custom
diff --git a/platforms/chibios/platform.mk b/platforms/chibios/platform.mk
index fd4c6bd2e5..b2a8ec89e1 100644
--- a/platforms/chibios/platform.mk
+++ b/platforms/chibios/platform.mk
@@ -442,9 +442,6 @@ LDFLAGS  += $(SHARED_LDFLAGS) $(SHARED_LDSYMBOLS) $(TOOLCHAIN_LDFLAGS) $(TOOLCHA
 # Tell QMK that we are hosting it on ChibiOS.
 OPT_DEFS += -DPROTOCOL_CHIBIOS
 
-# And what flavor of MCU
-OPT_DEFS += -DMCU_$(MCU_FAMILY)
-
 # ChibiOS supports synchronization primitives like a Mutex
 OPT_DEFS += -DPLATFORM_SUPPORTS_SYNCHRONIZATION