INCOMPLETE: use "friendly" names for GPIO ports

bogdanm · bogdanm · commit de5c3caa4820 · 2023-02-27T20:59:02.000+02:00
Starting with Zephyr 3.2.0, the `label` property of DT nodes was made obsolete, which means that is no longer possible to write: ``` pin = Pin(("GPIO_1", 21), Pin.IN) ``` Instead, a much less friendly format must be used: ``` pin = Pin(("gpio@842500", 21), Pin.IN) ``` This commit adds a new script (`gen_dt_node_names.py`) which is heavily based on [this script](https://github.com/zephyrproject-rtos/zephyr/blob/main/scripts/dts/gen_dts_cmake.py) and attempts to generate and map friendly names for DT nodes. For example, a node defined like this: ``` gpio0: gpio@842500 { ... } ``` will generate a mapping like this: ``` struct dt_node_name_map { const char *const gen_name; const char *const actual_name; }; static const struct dt_node_name_map dt_node_map[] = { {"GPIO_0", "gpio@842500"} ... } ``` The code then checks this mapping if the node name supplied by the user does not exist and uses the actual DT name instead.
diff --git a/ports/zephyr/CMakeLists.txt b/ports/zephyr/CMakeLists.txt
@@ -28,6 +28,7 @@ find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
 project(micropython)
 
 set(MICROPY_PORT_DIR    ${CMAKE_CURRENT_SOURCE_DIR})
+set(MICROPY_BUILD_DIR   ${MICROPY_PORT_DIR}/build)
 set(MICROPY_DIR         ${MICROPY_PORT_DIR}/../..)
 set(MICROPY_TARGET      micropython)
 
@@ -74,7 +75,12 @@ set(MICROPY_SOURCE_LIB
 )
 list(TRANSFORM MICROPY_SOURCE_LIB PREPEND ${MICROPY_DIR}/lib/)
 
+add_custom_command(OUTPUT ${MICROPY_BUILD_DIR}/gen_dt_node_names.h
+    DEPENDS ${MICROPY_BUILD_DIR}/zephyr/edt.pickle ${MICROPY_PORT_DIR}/gen_dt_node_names.py
+    COMMAND ${Python3_EXECUTABLE} ${MICROPY_PORT_DIR}/gen_dt_node_names.py -i ${MICROPY_BUILD_DIR}/zephyr/edt.pickle -o ${MICROPY_BUILD_DIR}/gen_dt_node_names.h)
+
 set(MICROPY_SOURCE_QSTR
+    ${MICROPY_BUILD_DIR}/gen_dt_node_names.h
     ${MICROPY_SOURCE_PY}
     ${MICROPY_SOURCE_EXTMOD}
     ${MICROPY_SOURCE_SHARED}
diff --git a/ports/zephyr/gen_dt_node_names.py b/ports/zephyr/gen_dt_node_names.py
@@ -0,0 +1,68 @@
+#!/usr/bin/env python3
+
+import argparse
+import os
+import sys
+import pickle
+import re
+
+# This is needed by the "pickle.load" call below
+zephyr_base = os.environ["ZEPHYR_BASE"]
+sys.path.insert(0, os.path.join(zephyr_base, "scripts", "dts", "python-devicetree", "src"))
+
+# The prefixes to look for in the device tree
+prefixes = ("gpio", "spi", "i2c", "uart")
+
+# Prefix for the generated header
+header_prefix = """#ifndef MICROPY_INCLUDED_ZEPHYR_GEN_DT_NODE_NAMES_H
+#define MICROPY_INCLUDED_ZEPHYR_GEN_DT_NODE_NAMES_H
+
+struct dt_node_name_map {
+    const char *const gen_name;
+    const char *const actual_name;
+};
+
+static const struct dt_node_name_map dt_node_map[] = {
+"""
+# Suffix for the generated header
+header_sufix = """};
+
+#endif
+"""
+
+def main():
+    parser = argparse.ArgumentParser(description="Generate friendly names for Zephyr DT nodess")
+    parser.add_argument("-i", "--input", required=True, help="path to edt.pickle")
+    parser.add_argument("-o", "--output", required=True, help="path to the output file")
+    args = parser.parse_args()
+
+    # Load the representation of the device tree generated by Zephyr
+    with open(args.input, 'rb') as f:
+        edt = pickle.load(f)
+
+    # Create regular expressions for all prefix that we need to check
+    all_re = re.compile(fr'^({"|".join(prefixes)})(\d+)$')
+
+    # Look in the device tree for all nodes with labels
+    name_map = {}
+    for n in edt.nodes:
+        if n.status == "okay": # consider only nodes that are enabled
+            # Check prefixes for all labels
+            for l in n.labels:
+                found = all_re.match(l)
+                if found != None:
+                    # Transform name (from "gpio0" to "GPIO_0" and so on)
+                    new_name = found.group(1).upper() + "_" + found.group(2)
+                    name_map[new_name] = n.name
+                    break
+
+    # Write data to output file
+    with open(args.output, "wt") as f:
+        f.write(header_prefix)
+        for n in name_map:
+            f.write(f'    {{"{n}", "{name_map[n]}"}},\n')
+        f.write("    {NULL, NULL}\n")
+        f.write(header_sufix)
+
+if __name__ == "__main__":
+    main()
diff --git a/ports/zephyr/machine_pin.c b/ports/zephyr/machine_pin.c
@@ -37,6 +37,7 @@
 #include "py/mphal.h"
 #include "shared/runtime/mpirq.h"
 #include "modmachine.h"
+#include "gen_dt_node_names.h"
 
 #if MICROPY_PY_MACHINE
 
@@ -133,6 +134,14 @@ mp_obj_t mp_pin_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw,
     const char *drv_name = mp_obj_str_get_str(items[0]);
     int wanted_pin = mp_obj_get_int(items[1]);
     const struct device *wanted_port = device_get_binding(drv_name);
+    if (!wanted_port) {
+        for (const struct dt_node_name_map *m = &dt_node_map[0]; m->gen_name != NULL; m ++) {
+            if (!strcmp(m->gen_name, drv_name)) {
+                wanted_port = device_get_binding(m->actual_name);
+                break;
+            }
+        }
+    }
     if (!wanted_port) {
         mp_raise_ValueError(MP_ERROR_TEXT("invalid port"));
     }
