micropython.mk

# This file is used by MicroPython Make-based builds such as the Unix port.
# For CMake-based builds, see the .cmake file in the same directory.

# When building Micropython, the parent directory of this module is given as:
#     make USER_C_MODULES=<path to workspace root>

LVMP_DIR := $(USERMOD_DIR)
# Where lvgl-bindings comes from, first match wins:
#   1. BINDINGS_DIR, from make's command line or the environment (a firmware
#      build that pins lvgl-bindings itself sets it);
#   2. an lvgl-bindings checkout beside this one;
#   3. the commit in LVGL_BINDINGS_COMMIT, fetched into .deps/ with only what
#      this module compiles (a clone on its own).
# The first two build the checkout as it is: if it isn't at the pinned commit,
# the build says so and carries on. Only the fetched copy must match the pin.
ifneq ($(strip $(BINDINGS_DIR)),)
BINDINGS_DIR := $(abspath $(BINDINGS_DIR))
LVMP_BINDINGS_FROM := BINDINGS_DIR
ifeq ($(wildcard $(BINDINGS_DIR)/lv_conf.h),)
$(error lvgl-micropython: BINDINGS_DIR=$(BINDINGS_DIR) is not an lvgl-bindings checkout (no lv_conf.h))
endif
else ifneq ($(wildcard $(LVMP_DIR)/../lvgl-bindings/lv_conf.h),)
BINDINGS_DIR := $(abspath $(LVMP_DIR)/../lvgl-bindings)
LVMP_BINDINGS_FROM := the lvgl-bindings beside lvgl-micropython
else
BINDINGS_DIR := $(abspath $(LVMP_DIR)/.deps/lvgl-bindings)
LVMP_BINDINGS_FROM := pin
LVMP_FETCH := $(shell bash $(LVMP_DIR)/scripts/fetch_bindings.sh 1>&2; echo $$?)
ifeq ($(wildcard $(BINDINGS_DIR)/lv_conf.h),)
$(error lvgl-micropython: fetching lvgl-bindings failed (scripts/fetch_bindings.sh exit $(LVMP_FETCH)); set BINDINGS_DIR to an lvgl-bindings checkout)
endif
endif
LVMP_C := $(BINDINGS_DIR)/generated/lvgl_micropython.c
LVGL_DIR := $(BINDINGS_DIR)/lvgl
SOURCES = $(shell find $(LVGL_DIR)/src -type f -name "*.c")
LV_BINDINGS_PIN := $(strip $(shell cat $(LVMP_DIR)/LVGL_BINDINGS_COMMIT 2>/dev/null))
ifeq ($(LV_BINDINGS_PIN),)
$(error Missing $(LVMP_DIR)/LVGL_BINDINGS_COMMIT)
endif
# 1 when the binding inputs are exactly the pinned commit's, with nothing
# uncommitted on top.
LV_BINDINGS_AT_PIN := $(shell \
	git -C $(BINDINGS_DIR) cat-file -e $(LV_BINDINGS_PIN)^{commit} 2>/dev/null && \
	git -C $(BINDINGS_DIR) diff --quiet $(LV_BINDINGS_PIN) -- generated/lvgl_micropython.c lvgl lv_conf.h && \
	git -C $(BINDINGS_DIR) diff --quiet -- generated/lvgl_micropython.c lvgl lv_conf.h && echo 1)
ifeq ($(LV_BINDINGS_AT_PIN),)
ifeq ($(LVMP_BINDINGS_FROM),pin)
$(error $(BINDINGS_DIR) does not match pinned binding inputs $(LV_BINDINGS_PIN); delete it and build again to refetch)
endif
LV_BINDINGS_HEAD := $(shell git -C $(BINDINGS_DIR) describe --always --dirty --abbrev=12 2>/dev/null || echo "not a git checkout")
$(info lvgl-micropython: note: building lvgl-bindings from $(BINDINGS_DIR) ($(LVMP_BINDINGS_FROM)) at $(LV_BINDINGS_HEAD),)
$(info   whose generated binding, lvgl or lv_conf.h differ from LVGL_BINDINGS_COMMIT $(LV_BINDINGS_PIN). Building it as it is.)
endif

# jpegio Phase 2 moved the JPEG decoder out of LVGL: LV_USE_TJPGD is 0 in the
# bindings (lvgl-bindings aa6c6bc), and the jpegio module registers its own
# TJpgDec with LVGL instead, so a firmware carries one decoder rather than two.
# Built without jpegio (micropython-pydevices' modules/jpegio since 2026-10-06;
# displayif's before), this module decodes PNG and LVGL's BIN and draws nothing
# at all for a JPEG -- silently, at run time. Say so at build time instead (#11).
ifeq ($(findstring jpegio,$(USER_C_MODULES)),)
$(info lvgl-micropython: no jpegio in this build -- lv.image will not draw a JPEG.)
$(info   jpegio owns the TJpgDec decoder; PNG and LVGL BIN still decode.)
$(info   Name jpegio as well for JPEG (build_mp.py --modules jpegio,lvgl-micropython).)
endif

# LVGL is available on every port, but its desktop/host-GUI and OS-specific
# driver backends (OpenGL/SDL/GLFW/X11/Wayland/evdev/libinput/qnx/uefi/nuttx/
# windows) plus the OpenGLES draw unit need host libraries and break cross
# builds (e.g. lv_opengles_shader.c fails -Werror). This exclusion lives in the
# module's own config: only desktop ports (unix/webassembly/windows) keep the
# full source sweep; every other (embedded) port drops these backends.
LVMP_PORT_DIR := $(abspath $(CURDIR))
LVMP_IS_DESKTOP := $(findstring /ports/unix,$(LVMP_PORT_DIR))$(findstring /ports/webassembly,$(LVMP_PORT_DIR))$(findstring /ports/windows,$(LVMP_PORT_DIR))
ifeq ($(LVMP_IS_DESKTOP),)
LVMP_EXCLUDE_DIRS := \
    $(LVGL_DIR)/src/drivers/opengles \
    $(LVGL_DIR)/src/drivers/sdl \
    $(LVGL_DIR)/src/drivers/glfw \
    $(LVGL_DIR)/src/drivers/x11 \
    $(LVGL_DIR)/src/drivers/wayland \
    $(LVGL_DIR)/src/drivers/evdev \
    $(LVGL_DIR)/src/drivers/libinput \
    $(LVGL_DIR)/src/drivers/qnx \
    $(LVGL_DIR)/src/drivers/uefi \
    $(LVGL_DIR)/src/drivers/nuttx \
    $(LVGL_DIR)/src/drivers/windows \
    $(LVGL_DIR)/src/draw/opengles \
    $(LVGL_DIR)/src/libs/gltf
SOURCES := $(foreach s,$(SOURCES),$(if $(strip $(foreach d,$(LVMP_EXCLUDE_DIRS),$(findstring $(d)/,$(s)))),,$(s)))
endif

SOURCES += $(LVMP_DIR)/src/lv_mem_core_micropython.c

$(if $(wildcard $(LVMP_C)),,$(error $(LVMP_C) not found. Sync an exact lvgl-bindings commit or release tag))

# -Wno-unused-function here is not enough on ports that append -Werror after py.mk
# (e.g. webassembly); those ports add -Wno-unused-function after -Werror too.
CFLAGS_USERMOD += -I$(BINDINGS_DIR) -I$(LVMP_DIR) -Wno-unused-function
SRC_USERMOD_LIB_C += $(SOURCES)
SRC_USERMOD_C += $(LVMP_C)
SRC_USERMOD_C += $(LVMP_DIR)/src/lvgl_micropython_build.c

# --- which lvmp this firmware was built from ----------------------
# Computed at build time from this repo's own git, never stored; "unknown" when
# there is no git (a tarball). Read on a target as <module>.__revision__.
LVMP_REVISION := $(shell git -C $(LVMP_DIR) describe --always --dirty --abbrev=7 2>/dev/null || echo unknown)
CFLAGS_USERMOD += -DLVMP_REVISION='"$(LVMP_REVISION)"'

# With LV_USE_FLOAT=1, upstream LVGL trips -Werror=double-promotion / float-conversion.
# Port Makefiles (unix/webassembly) append -Wdouble-promotion after CFLAGS_USERMOD,
# so put the suppress on the LVGL object rules (same idea as circuitpython.mk).
# GCC 16 also counts a variable only ever incremented as set-but-unused
# (lv_buttonmatrix.c's txt_tot_i), which older GCC did not.
LVMP_FLOAT_CFLAGS := -Wno-double-promotion -Wno-float-conversion -Wno-unused-but-set-variable
# The object name a user-module source lands under is not the same on every
# MicroPython. Up to v1.28.0 the USER_C_MODULES prefix was stripped, so the
# object was $(BUILD)/lvgl-bindings/lvgl/src/....o; v1.29.0 keeps the absolute
# source path, giving $(BUILD)//home/.../lvgl-bindings/lvgl/src/....o. A rule
# written for one names a target that does not exist on the other, the flags
# never apply, and upstream LVGL then fails the port's -Werror=double-promotion
# with no hint that a suppression was even attempted. Declare both spellings.
# py.mk names a user-module object $(BUILD)/<module dir basename>/<path inside
# the module>, whatever USER_C_MODULES was (a parent directory, or the module
# directories themselves from c_module()); derive it from this module's own
# directory rather than from USER_C_MODULES.
# The second spelling can't be a target on Windows: a path with a drive (C:/...) under
# $(BUILD) holds a second colon, which make reads as a static pattern rule.
# lvgl-bindings is often not inside this module (a sibling checkout, or the one
# a firmware build hands over in BINDINGS_DIR), and py.mk only shortens paths
# under a module directory, so its objects kept the absolute path and, on
# Windows, the drive's colon. Register it as a module directory too: its
# objects become $(BUILD)/<bindings dir basename>/..., like a module's.
ifeq ($(filter $(LVMP_DIR)/%,$(BINDINGS_DIR)),)
USERMOD_DIRS += $(BINDINGS_DIR)
endif
LVMP_OBJ = $(BUILD)/$(patsubst $(BINDINGS_DIR)/%,$(notdir $(BINDINGS_DIR))/%,$(patsubst $(LVMP_DIR)/%,$(notdir $(LVMP_DIR))/%,$(1))) $(if $(findstring :,$(1)),,$(BUILD)/$(1))
$(foreach s,$(SOURCES),\
	$(eval $(call LVMP_OBJ,$(s:.c=.o)): CFLAGS += $(LVMP_FLOAT_CFLAGS)))
$(eval $(call LVMP_OBJ,$(LVMP_C:.c=.o)): CFLAGS += $(LVMP_FLOAT_CFLAGS))
$(eval $(call LVMP_OBJ,$(LVMP_DIR)/src/lv_mem_core_micropython.o): CFLAGS += $(LVMP_FLOAT_CFLAGS))