https://bugs.gentoo.org/898678

1. https://github.com/trezor/cython-hidapi/commit/749da6931f57c4c30596de678125648ccfd6e1cd
2. https://github.com/trezor/cython-hidapi/pull/159

From 749da6931f57c4c30596de678125648ccfd6e1cd Mon Sep 17 00:00:00 2001
From: Pavol Rusnak <pavol@rusnak.io>
Date: Thu, 20 Jul 2023 13:09:19 +0200
Subject: [PATCH] Require Cython<3 instead of Cython

---
 setup.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/setup.py b/setup.py
index 7e3eb29c..4c311ba4 100755
--- a/setup.py
+++ b/setup.py
@@ -136,6 +136,6 @@ def find_version():
         "Programming Language :: Python :: 3.9",
     ],
     ext_modules=modules,
-    setup_requires=["Cython"],
+    setup_requires=["Cython<3"],
     install_requires=["setuptools>=19.0"],
 )

From 7dad82b125fdca5df83c00fc711151c35aaa5125 Mon Sep 17 00:00:00 2001
From: Shawn Hoffman <godisgovernment@gmail.com>
Date: Mon, 11 Sep 2023 17:27:52 -0700
Subject: [PATCH 1/4] use pyxdep file to locate chid.pxd

---
 hid.pyxdep | 1 +
 setup.py   | 4 ++--
 2 files changed, 3 insertions(+), 2 deletions(-)
 create mode 100644 hid.pyxdep

diff --git a/hid.pyxdep b/hid.pyxdep
new file mode 100644
index 00000000..7480bc82
--- /dev/null
+++ b/hid.pyxdep
@@ -0,0 +1 @@
+chid.pxd
diff --git a/setup.py b/setup.py
index 4c311ba4..73066b06 100755
--- a/setup.py
+++ b/setup.py
@@ -9,7 +9,7 @@
 hidapi_include = os.path.join(hidapi_topdir, "hidapi")
 system_hidapi = 0
 libs = []
-src = ["hid.pyx", "chid.pxd"]
+src = ["hid.pyx"]
 
 
 def hidapi_src(platform):
@@ -42,7 +42,7 @@ def hidapi_src(platform):
             )
         )
     libs = ["udev", "rt"]
-    src = ["hidraw.pyx", "chid.pxd"]
+    src = ["hidraw.pyx"]
     if system_hidapi == 1:
         libs.append("hidapi-hidraw")
     else:

From 4c78f61c7815d1005023d69c42ae777cfee021c1 Mon Sep 17 00:00:00 2001
From: Shawn Hoffman <godisgovernment@gmail.com>
Date: Mon, 11 Sep 2023 17:28:33 -0700
Subject: [PATCH 2/4] specify language_level for cython

---
 setup.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/setup.py b/setup.py
index 73066b06..6a3e0af0 100755
--- a/setup.py
+++ b/setup.py
@@ -1,5 +1,6 @@
 #!/usr/bin/python
 from setuptools import setup, Extension
+from Cython.Build import cythonize
 import os
 import sys
 import subprocess
@@ -135,7 +136,7 @@ def find_version():
         "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
     ],
-    ext_modules=modules,
+    ext_modules=cythonize(modules, language_level=3),
     setup_requires=["Cython<3"],
     install_requires=["setuptools>=19.0"],
 )

From d73b4cc6706d4220d28df866504e989ab616616a Mon Sep 17 00:00:00 2001
From: Shawn Hoffman <godisgovernment@gmail.com>
Date: Mon, 11 Sep 2023 17:31:37 -0700
Subject: [PATCH 3/4] use pyproject.toml allow using recent cython the
 expectation is that one would use the `build` tool instead of invoking
 setup.py.

---
 pyproject.toml   | 3 +++
 setup.py         | 1 -
 3 files changed, 3 insertions(+), 2 deletions(-)
 create mode 100644 pyproject.toml
 delete mode 100644 requirements.txt

diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 00000000..c07b1d35
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,3 @@
+[build-system]
+requires = ["setuptools", "Cython"]
+build-backend = "setuptools.build_meta"
diff --git a/setup.py b/setup.py
index 6a3e0af0..9dcdb0ee 100755
--- a/setup.py
+++ b/setup.py
@@ -137,6 +137,5 @@ def find_version():
         "Programming Language :: Python :: 3.9",
     ],
     ext_modules=cythonize(modules, language_level=3),
-    setup_requires=["Cython<3"],
     install_requires=["setuptools>=19.0"],
 )