CLI: Teaching the CLI to flash binaries (#16584)

Co-authored-by: Ryan <fauxpark@gmail.com>
Co-authored-by: Sergey Vlasov <sigprof@gmail.com>
Co-authored-by: Joel Challis <git@zvecr.com>
Co-authored-by: Nick Brassel <nick@tzarc.org>

8 files changed, 363 insertions, 93 deletions

diff --git a/docs/cli_commands.md b/docs/cli_commands.md
index 56767d962b..4608ed85b6 100644
--- a/docs/cli_commands.md
+++ b/docs/cli_commands.md
@@ -90,6 +90,8 @@ This command is similar to `qmk compile`, but can also target a bootloader. The
 
 This command is directory aware. It will automatically fill in KEYBOARD and/or KEYMAP if you are in a keyboard or keymap directory.
 
+This command can also flash binary firmware files (hex or bin) such as the ones produced by [Configurator](https://config.qmk.fm).
+
 **Usage for Configurator Exports**:
 
 ```
@@ -102,6 +104,21 @@ qmk flash [-bl <bootloader>] [-c] [-e <var>=<value>] [-j <num_jobs>] <configurat
 qmk flash -kb <keyboard_name> -km <keymap_name> [-bl <bootloader>] [-c] [-e <var>=<value>] [-j <num_jobs>]
 ```
 
+**Usage for pre-compiled firmwares**:
+
+**Note**: The microcontroller needs to be specified (`-m` argument) for keyboards with the following bootloaders:
+* HalfKay
+* QMK HID
+* USBaspLoader
+
+ISP flashing is also supported with the following flashers and require the microcontroller to be specified:
+* USBasp
+* USBtinyISP
+
+```
+qmk flash [-m <microcontroller>] <compiledFirmware.[bin|hex]>
+```
+
 **Listing the Bootloaders**
 
 ```
diff --git a/lib/python/qmk/cli/__init__.py b/lib/python/qmk/cli/__init__.py
index 8a507677ef..f05b2a746e 100644
--- a/lib/python/qmk/cli/__init__.py
+++ b/lib/python/qmk/cli/__init__.py
@@ -15,6 +15,7 @@ from milc.questions import yesno
 import_names = {
     # A mapping of package name to importable name
     'pep8-naming': 'pep8ext_naming',
+    'pyserial': 'serial',
     'pyusb': 'usb.core',
     'qmk-dotty-dict': 'dotty_dict',
     'pillow': 'PIL'
diff --git a/lib/python/qmk/cli/doctor/linux.py b/lib/python/qmk/cli/doctor/linux.py
index 94683d3307..a803305c0d 100644
--- a/lib/python/qmk/cli/doctor/linux.py
+++ b/lib/python/qmk/cli/doctor/linux.py
@@ -6,7 +6,7 @@ from pathlib import Path
 
 from milc import cli
 
-from qmk.constants import QMK_FIRMWARE
+from qmk.constants import QMK_FIRMWARE, BOOTLOADER_VIDS_PIDS
 from .check import CheckStatus
 
 
@@ -26,6 +26,18 @@ def _udev_rule(vid, pid=None, *args):
     return rule
 
 
+def _generate_desired_rules(bootloader_vids_pids):
+    rules = dict()
+    for bl in bootloader_vids_pids.keys():
+        rules[bl] = set()
+        for vid_pid in bootloader_vids_pids[bl]:
+            if bl == 'caterina' or bl == 'md-boot':
+                rules[bl].add(_udev_rule(vid_pid[0], vid_pid[1], 'ENV{ID_MM_DEVICE_IGNORE}="1"'))
+            else:
+                rules[bl].add(_udev_rule(vid_pid[0], vid_pid[1]))
+    return rules
+
+
 def _deprecated_udev_rule(vid, pid=None):
     """ Helper function that return udev rules
 
@@ -47,47 +59,8 @@ def check_udev_rules():
         Path("/run/udev/rules.d/"),
         Path("/etc/udev/rules.d/"),
     ]
-    desired_rules = {
-        'atmel-dfu': {
-            _udev_rule("03eb", "2fef"),  # ATmega16U2
-            _udev_rule("03eb", "2ff0"),  # ATmega32U2
-            _udev_rule("03eb", "2ff3"),  # ATmega16U4
-            _udev_rule("03eb", "2ff4"),  # ATmega32U4
-            _udev_rule("03eb", "2ff9"),  # AT90USB64
-            _udev_rule("03eb", "2ffa"),  # AT90USB162
-            _udev_rule("03eb", "2ffb")  # AT90USB128
-        },
-        'kiibohd': {_udev_rule("1c11", "b007")},
-        'stm32': {
-            _udev_rule("1eaf", "0003"),  # STM32duino
-            _udev_rule("0483", "df11")  # STM32 DFU
-        },
-        'bootloadhid': {_udev_rule("16c0", "05df")},
-        'usbasploader': {_udev_rule("16c0", "05dc")},
-        'massdrop': {_udev_rule("03eb", "6124", 'ENV{ID_MM_DEVICE_IGNORE}="1"')},
-        'caterina': {
-            # Spark Fun Electronics
-            _udev_rule("1b4f", "9203", 'ENV{ID_MM_DEVICE_IGNORE}="1"'),  # Pro Micro 3V3/8MHz
-            _udev_rule("1b4f", "9205", 'ENV{ID_MM_DEVICE_IGNORE}="1"'),  # Pro Micro 5V/16MHz
-            _udev_rule("1b4f", "9207", 'ENV{ID_MM_DEVICE_IGNORE}="1"'),  # LilyPad 3V3/8MHz (and some Pro Micro clones)
-            # Pololu Electronics
-            _udev_rule("1ffb", "0101", 'ENV{ID_MM_DEVICE_IGNORE}="1"'),  # A-Star 32U4
-            # Arduino SA
-            _udev_rule("2341", "0036", 'ENV{ID_MM_DEVICE_IGNORE}="1"'),  # Leonardo
-            _udev_rule("2341", "0037", 'ENV{ID_MM_DEVICE_IGNORE}="1"'),  # Micro
-            # Adafruit Industries LLC
-            _udev_rule("239a", "000c", 'ENV{ID_MM_DEVICE_IGNORE}="1"'),  # Feather 32U4
-            _udev_rule("239a", "000d", 'ENV{ID_MM_DEVICE_IGNORE}="1"'),  # ItsyBitsy 32U4 3V3/8MHz
-            _udev_rule("239a", "000e", 'ENV{ID_MM_DEVICE_IGNORE}="1"'),  # ItsyBitsy 32U4 5V/16MHz
-            # dog hunter AG
-            _udev_rule("2a03", "0036", 'ENV{ID_MM_DEVICE_IGNORE}="1"'),  # Leonardo
-            _udev_rule("2a03", "0037", 'ENV{ID_MM_DEVICE_IGNORE}="1"')  # Micro
-        },
-        'hid-bootloader': {
-            _udev_rule("03eb", "2067"),  # QMK HID
-            _udev_rule("16c0", "0478")  # PJRC halfkay
-        }
-    }
+
+    desired_rules = _generate_desired_rules(BOOTLOADER_VIDS_PIDS)
 
     # These rules are no longer recommended, only use them to check for their presence.
     deprecated_rules = {
diff --git a/lib/python/qmk/cli/flash.py b/lib/python/qmk/cli/flash.py
index ebe739c50e..c39f4b36d4 100644
--- a/lib/python/qmk/cli/flash.py
+++ b/lib/python/qmk/cli/flash.py
@@ -4,6 +4,7 @@ You can compile a keymap already in the repo or using a QMK Configurator export.
 A bootloader must be specified.
 """
 from subprocess import DEVNULL
+import sys
 
 from argcomplete.completers import FilesCompleter
 from milc import cli
@@ -12,6 +13,7 @@ import qmk.path
 from qmk.decorators import automagic_keyboard, automagic_keymap
 from qmk.commands import compile_configurator_json, create_make_command, parse_configurator_json
 from qmk.keyboard import keyboard_completer, keyboard_folder
+from qmk.flashers import flasher
 
 
 def print_bootloader_help():
@@ -38,9 +40,10 @@ def print_bootloader_help():
     cli.echo('For more info, visit https://docs.qmk.fm/#/flashing')
 
 
-@cli.argument('filename', nargs='?', arg_only=True, type=qmk.path.FileType('r'), completer=FilesCompleter('.json'), help='The configurator export JSON to compile.')
+@cli.argument('filename', nargs='?', arg_only=True, type=qmk.path.FileType('r'), completer=FilesCompleter('.json'), help='A configurator export JSON to be compiled and flashed or a pre-compiled binary firmware file (bin/hex) to be flashed.')
 @cli.argument('-b', '--bootloaders', action='store_true', help='List the available bootloaders.')
 @cli.argument('-bl', '--bootloader', default='flash', help='The flash command, corresponding to qmk\'s make options of bootloaders.')
+@cli.argument('-m', '--mcu', help='The MCU name. Required for HalfKay, HID, USBAspLoader and ISP flashing.')
 @cli.argument('-km', '--keymap', help='The keymap to build a firmware for. Use this if you dont have a configurator file. Ignored when a configurator file is supplied.')
 @cli.argument('-kb', '--keyboard', type=keyboard_folder, completer=keyboard_completer, help='The keyboard to build a firmware for. Use this if you dont have a configurator file. Ignored when a configurator file is supplied.')
 @cli.argument('-n', '--dry-run', arg_only=True, action='store_true', help="Don't actually build, just show the make command to be run.")
@@ -53,6 +56,8 @@ def print_bootloader_help():
 def flash(cli):
     """Compile and or flash QMK Firmware or keyboard/layout
 
+    If a binary firmware is supplied, try to flash that.
+
     If a Configurator JSON export is supplied this command will create a new keymap. Keymap and Keyboard arguments
     will be ignored.
 
@@ -60,56 +65,69 @@ def flash(cli):
 
     If bootloader is omitted the make system will use the configured bootloader for that keyboard.
     """
-    if cli.args.clean and not cli.args.filename and not cli.args.dry_run:
-        if cli.config.flash.keyboard and cli.config.flash.keymap:
-            command = create_make_command(cli.config.flash.keyboard, cli.config.flash.keymap, 'clean')
-            cli.run(command, capture_output=False, stdin=DEVNULL)
-
-    # Build the environment vars
-    envs = {}
-    for env in cli.args.env:
-        if '=' in env:
-            key, value = env.split('=', 1)
-            envs[key] = value
-        else:
-            cli.log.warning('Invalid environment variable: %s', env)
-
-    # Determine the compile command
-    command = ''
-
-    if cli.args.bootloaders:
-        # Provide usage and list bootloaders
-        cli.echo('usage: qmk flash [-h] [-b] [-n] [-kb KEYBOARD] [-km KEYMAP] [-bl BOOTLOADER] [filename]')
-        print_bootloader_help()
-        return False
-
-    if cli.args.filename:
-        # Handle compiling a configurator JSON
-        user_keymap = parse_configurator_json(cli.args.filename)
-        keymap_path = qmk.path.keymap(user_keymap['keyboard'])
-        command = compile_configurator_json(user_keymap, cli.args.bootloader, parallel=cli.config.flash.parallel, **envs)
-
-        cli.log.info('Wrote keymap to {fg_cyan}%s/%s/keymap.c', keymap_path, user_keymap['keymap'])
+    if cli.args.filename and cli.args.filename.suffix in ['.bin', '.hex']:
+        # Try to flash binary firmware
+        cli.echo('Flashing binary firmware...\nPlease reset your keyboard into bootloader mode now!\nPress Ctrl-C to exit.\n')
+        try:
+            err, msg = flasher(cli.args.mcu, cli.args.filename)
+            if err:
+                cli.log.error(msg)
+                return False
+        except KeyboardInterrupt:
+            cli.log.info('Ctrl-C was pressed, exiting...')
+            sys.exit(0)
 
     else:
-        if cli.config.flash.keyboard and cli.config.flash.keymap:
-            # Generate the make command for a specific keyboard/keymap.
-            command = create_make_command(cli.config.flash.keyboard, cli.config.flash.keymap, cli.args.bootloader, parallel=cli.config.flash.parallel, **envs)
-
-        elif not cli.config.flash.keyboard:
-            cli.log.error('Could not determine keyboard!')
-        elif not cli.config.flash.keymap:
-            cli.log.error('Could not determine keymap!')
-
-    # Compile the firmware, if we're able to
-    if command:
-        cli.log.info('Compiling keymap with {fg_cyan}%s', ' '.join(command))
-        if not cli.args.dry_run:
-            cli.echo('\n')
-            compile = cli.run(command, capture_output=False, stdin=DEVNULL)
-            return compile.returncode
+        if cli.args.clean and not cli.args.filename and not cli.args.dry_run:
+            if cli.config.flash.keyboard and cli.config.flash.keymap:
+                command = create_make_command(cli.config.flash.keyboard, cli.config.flash.keymap, 'clean')
+                cli.run(command, capture_output=False, stdin=DEVNULL)
+
+        # Build the environment vars
+        envs = {}
+        for env in cli.args.env:
+            if '=' in env:
+                key, value = env.split('=', 1)
+                envs[key] = value
+            else:
+                cli.log.warning('Invalid environment variable: %s', env)
+
+        # Determine the compile command
+        command = ''
+
+        if cli.args.bootloaders:
+            # Provide usage and list bootloaders
+            cli.echo('usage: qmk flash [-h] [-b] [-n] [-kb KEYBOARD] [-km KEYMAP] [-bl BOOTLOADER] [filename]')
+            print_bootloader_help()
+            return False
+
+        if cli.args.filename:
+            # Handle compiling a configurator JSON
+            user_keymap = parse_configurator_json(cli.args.filename)
+            keymap_path = qmk.path.keymap(user_keymap['keyboard'])
+            command = compile_configurator_json(user_keymap, cli.args.bootloader, parallel=cli.config.flash.parallel, **envs)
+
+            cli.log.info('Wrote keymap to {fg_cyan}%s/%s/keymap.c', keymap_path, user_keymap['keymap'])
 
-    else:
-        cli.log.error('You must supply a configurator export, both `--keyboard` and `--keymap`, or be in a directory for a keyboard or keymap.')
-        cli.echo('usage: qmk flash [-h] [-b] [-n] [-kb KEYBOARD] [-km KEYMAP] [-bl BOOTLOADER] [filename]')
-        return False
+        else:
+            if cli.config.flash.keyboard and cli.config.flash.keymap:
+                # Generate the make command for a specific keyboard/keymap.
+                command = create_make_command(cli.config.flash.keyboard, cli.config.flash.keymap, cli.args.bootloader, parallel=cli.config.flash.parallel, **envs)
+
+            elif not cli.config.flash.keyboard:
+                cli.log.error('Could not determine keyboard!')
+            elif not cli.config.flash.keymap:
+                cli.log.error('Could not determine keymap!')
+
+        # Compile the firmware, if we're able to
+        if command:
+            cli.log.info('Compiling keymap with {fg_cyan}%s', ' '.join(command))
+            if not cli.args.dry_run:
+                cli.echo('\n')
+                compile = cli.run(command, capture_output=False, stdin=DEVNULL)
+                return compile.returncode
+
+        else:
+            cli.log.error('You must supply a configurator export, both `--keyboard` and `--keymap`, or be in a directory for a keyboard or keymap.')
+            cli.echo('usage: qmk flash [-h] [-b] [-n] [-kb KEYBOARD] [-km KEYMAP] [-bl BOOTLOADER] [filename]')
+            return False
diff --git a/lib/python/qmk/constants.py b/lib/python/qmk/constants.py
index 7da9df1d8a..10da5e7e8e 100644
--- a/lib/python/qmk/constants.py
+++ b/lib/python/qmk/constants.py
@@ -64,6 +64,54 @@ LEGACY_KEYCODES = {  # Comment here is to force multiline formatting
     'RESET': 'QK_BOOT'
 }
 
+# Map VID:PID values to bootloaders
+BOOTLOADER_VIDS_PIDS = {
+    'atmel-dfu': {
+        ("03eb", "2fef"),  # ATmega16U2
+        ("03eb", "2ff0"),  # ATmega32U2
+        ("03eb", "2ff3"),  # ATmega16U4
+        ("03eb", "2ff4"),  # ATmega32U4
+        ("03eb", "2ff9"),  # AT90USB64
+        ("03eb", "2ffa"),  # AT90USB162
+        ("03eb", "2ffb")  # AT90USB128
+    },
+    'kiibohd': {("1c11", "b007")},
+    'stm32-dfu': {
+        ("1eaf", "0003"),  # STM32duino
+        ("0483", "df11")  # STM32 DFU
+    },
+    'apm32-dfu': {("314b", "0106")},
+    'gd32v-dfu': {("28e9", "0189")},
+    'bootloadhid': {("16c0", "05df")},
+    'usbasploader': {("16c0", "05dc")},
+    'usbtinyisp': {("1782", "0c9f")},
+    'md-boot': {("03eb", "6124")},
+    'caterina': {
+        # pid.codes shared PID
+        ("1209", "9203"),  # Keyboardio Atreus 2 Bootloader
+        # Spark Fun Electronics
+        ("1b4f", "9203"),  # Pro Micro 3V3/8MHz
+        ("1b4f", "9205"),  # Pro Micro 5V/16MHz
+        ("1b4f", "9207"),  # LilyPad 3V3/8MHz (and some Pro Micro clones)
+        # Pololu Electronics
+        ("1ffb", "0101"),  # A-Star 32U4
+        # Arduino SA
+        ("2341", "0036"),  # Leonardo
+        ("2341", "0037"),  # Micro
+        # Adafruit Industries LLC
+        ("239a", "000c"),  # Feather 32U4
+        ("239a", "000d"),  # ItsyBitsy 32U4 3V3/8MHz
+        ("239a", "000e"),  # ItsyBitsy 32U4 5V/16MHz
+        # dog hunter AG
+        ("2a03", "0036"),  # Leonardo
+        ("2a03", "0037")  # Micro
+    },
+    'hid-bootloader': {
+        ("03eb", "2067"),  # QMK HID
+        ("16c0", "0478")  # PJRC halfkay
+    }
+}
+
 # Common format strings
 DATE_FORMAT = '%Y-%m-%d'
 DATETIME_FORMAT = '%Y-%m-%d %H:%M:%S %Z'
diff --git a/lib/python/qmk/flashers.py b/lib/python/qmk/flashers.py
new file mode 100644
index 0000000000..a9cf726b44
--- /dev/null
+++ b/lib/python/qmk/flashers.py
@@ -0,0 +1,203 @@
+import shutil
+import time
+import os
+import signal
+
+import usb.core
+
+from qmk.constants import BOOTLOADER_VIDS_PIDS
+from milc import cli
+
+# yapf: disable
+_PID_TO_MCU = {
+    '2fef': 'atmega16u2',
+    '2ff0': 'atmega32u2',
+    '2ff3': 'atmega16u4',
+    '2ff4': 'atmega32u4',
+    '2ff9': 'at90usb64',
+    '2ffa': 'at90usb162',
+    '2ffb': 'at90usb128'
+}
+
+AVRDUDE_MCU = {
+    'atmega32a': 'm32',
+    'atmega328p': 'm328p',
+    'atmega328': 'm328',
+}
+# yapf: enable
+
+
+class DelayedKeyboardInterrupt:
+    # Custom interrupt handler to delay the processing of Ctrl-C
+    # https://stackoverflow.com/a/21919644
+    def __enter__(self):
+        self.signal_received = False
+        self.old_handler = signal.signal(signal.SIGINT, self.handler)
+
+    def handler(self, sig, frame):
+        self.signal_received = (sig, frame)
+
+    def __exit__(self, type, value, traceback):
+        signal.signal(signal.SIGINT, self.old_handler)
+        if self.signal_received:
+            self.old_handler(*self.signal_received)
+
+
+# TODO: Make this more generic, so cli/doctor/check.py and flashers.py can share the code
+def _check_dfu_programmer_version():
+    # Return True if version is higher than 0.7.0: supports '--force'
+    check = cli.run(['dfu-programmer', '--version'], combined_output=True, timeout=5)
+    first_line = check.stdout.split('\n')[0]
+    version_number = first_line.split()[1]
+    maj, min_, bug = version_number.split('.')
+    if int(maj) >= 0 and int(min_) >= 7:
+        return True
+    else:
+        return False
+
+
+def _find_bootloader():
+    # To avoid running forever in the background, only look for bootloaders for 10min
+    start_time = time.time()
+    while time.time() - start_time < 600:
+        for bl in BOOTLOADER_VIDS_PIDS:
+            for vid, pid in BOOTLOADER_VIDS_PIDS[bl]:
+                vid_hex = int(f'0x{vid}', 0)
+                pid_hex = int(f'0x{pid}', 0)
+                with DelayedKeyboardInterrupt():
+                    # PyUSB does not like to be interrupted by Ctrl-C
+                    # therefore we catch the interrupt with a custom handler
+                    # and only process it once pyusb finished
+                    dev = usb.core.find(idVendor=vid_hex, idProduct=pid_hex)
+                if dev:
+                    if bl == 'atmel-dfu':
+                        details = _PID_TO_MCU[pid]
+                    elif bl == 'caterina':
+                        details = (vid_hex, pid_hex)
+                    elif bl == 'hid-bootloader':
+                        if vid == '16c0' and pid == '0478':
+                            details = 'halfkay'
+                        else:
+                            details = 'qmk-hid'
+                    elif bl == 'stm32-dfu' or bl == 'apm32-dfu' or bl == 'gd32v-dfu' or bl == 'kiibohd':
+                        details = (vid, pid)
+                    else:
+                        details = None
+                    return (bl, details)
+        time.sleep(0.1)
+    return (None, None)
+
+
+def _find_serial_port(vid, pid):
+    if 'windows' in cli.platform.lower():
+        from serial.tools.list_ports_windows import comports
+        platform = 'windows'
+    else:
+        from serial.tools.list_ports_posix import comports
+        platform = 'posix'
+
+    start_time = time.time()
+    # Caterina times out after 8 seconds
+    while time.time() - start_time < 8:
+        for port in comports():
+            port, desc, hwid = port
+            if f'{vid:04x}:{pid:04x}' in hwid.casefold():
+                if platform == 'windows':
+                    time.sleep(1)
+                    return port
+                else:
+                    start_time = time.time()
+                    # Wait until the port becomes writable before returning
+                    while time.time() - start_time < 8:
+                        if os.access(port, os.W_OK):
+                            return port
+                        else:
+                            time.sleep(0.5)
+                return None
+    return None
+
+
+def _flash_caterina(details, file):
+    port = _find_serial_port(details[0], details[1])
+    if port:
+        cli.run(['avrdude', '-p', 'atmega32u4', '-c', 'avr109', '-U', f'flash:w:{file}:i', '-P', port], capture_output=False)
+        return False
+    else:
+        return True
+
+
+def _flash_atmel_dfu(mcu, file):
+    force = '--force' if _check_dfu_programmer_version() else ''
+    cli.run(['dfu-programmer', mcu, 'erase', force], capture_output=False)
+    cli.run(['dfu-programmer', mcu, 'flash', force, file], capture_output=False)
+    cli.run(['dfu-programmer', mcu, 'reset'], capture_output=False)
+
+
+def _flash_hid_bootloader(mcu, details, file):
+    if details == 'halfkay':
+        if shutil.which('teensy-loader-cli'):
+            cmd = 'teensy-loader-cli'
+        elif shutil.which('teensy_loader_cli'):
+            cmd = 'teensy_loader_cli'
+
+    # Use 'hid_bootloader_cli' for QMK HID and as a fallback for HalfKay
+    if not cmd:
+        if shutil.which('hid_bootloader_cli'):
+            cmd = 'hid_bootloader_cli'
+        else:
+            return True
+
+    cli.run([cmd, f'-mmcu={mcu}', '-w', '-v', file], capture_output=False)
+
+
+def _flash_dfu_util(details, file):
+    # STM32duino
+    if details[0] == '1eaf' and details[1] == '0003':
+        cli.run(['dfu-util', '-a', '2', '-d', f'{details[0]}:{details[1]}', '-R', '-D', file], capture_output=False)
+    # kiibohd
+    elif details[0] == '1c11' and details[1] == 'b007':
+        cli.run(['dfu-util', '-a', '0', '-d', f'{details[0]}:{details[1]}', '-D', file], capture_output=False)
+    # STM32, APM32, or GD32V DFU
+    else:
+        cli.run(['dfu-util', '-a', '0', '-d', f'{details[0]}:{details[1]}', '-s', '0x08000000:leave', '-D', file], capture_output=False)
+
+
+def _flash_isp(mcu, programmer, file):
+    programmer = 'usbasp' if programmer == 'usbasploader' else 'usbtiny'
+    # Check if the provide mcu has an avrdude-specific name, otherwise pass on what the user provided
+    mcu = AVRDUDE_MCU.get(mcu, mcu)
+    cli.run(['avrdude', '-p', mcu, '-c', programmer, '-U', f'flash:w:{file}:i'], capture_output=False)
+
+
+def _flash_mdloader(file):
+    cli.run(['mdloader', '--first', '--download', file, '--restart'], capture_output=False)
+
+
+def flasher(mcu, file):
+    bl, details = _find_bootloader()
+    # Add a small sleep to avoid race conditions
+    time.sleep(1)
+    if bl == 'atmel-dfu':
+        _flash_atmel_dfu(details, file.name)
+    elif bl == 'caterina':
+        if _flash_caterina(details, file.name):
+            return (True, "The Caterina bootloader was found but is not writable. Check 'qmk doctor' output for advice.")
+    elif bl == 'hid-bootloader':
+        if mcu:
+            if _flash_hid_bootloader(mcu, details, file.name):
+                return (True, "Please make sure 'teensy_loader_cli' or 'hid_bootloader_cli' is available on your system.")
+        else:
+            return (True, "Specifying the MCU with '-m' is necessary for HalfKay/HID bootloaders!")
+    elif bl == 'stm32-dfu' or bl == 'apm32-dfu' or bl == 'gd32v-dfu' or bl == 'kiibohd':
+        _flash_dfu_util(details, file.name)
+    elif bl == 'usbasploader' or bl == 'usbtinyisp':
+        if mcu:
+            _flash_isp(mcu, bl, file.name)
+        else:
+            return (True, "Specifying the MCU with '-m' is necessary for ISP flashing!")
+    elif bl == 'md-boot':
+        _flash_mdloader(file.name)
+    else:
+        return (True, "Known bootloader found but flashing not currently supported!")
+
+    return (False, None)
diff --git a/requirements.txt b/requirements.txt
index e09d58d829..9c192b0f0f 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -7,6 +7,7 @@ hjson
 jsonschema>=4
 milc>=1.4.2
 pygments
+pyserial
 pyusb
 qmk-dotty-dict
 pillow
diff --git a/util/udev/50-qmk.rules b/util/udev/50-qmk.rules
index 57806f9df0..86f1dc9004 100644
--- a/util/udev/50-qmk.rules
+++ b/util/udev/50-qmk.rules
@@ -28,6 +28,9 @@ SUBSYSTEMS=="usb", ATTRS{idVendor}=="16c0", ATTRS{idProduct}=="05df", TAG+="uacc
 # USBAspLoader
 SUBSYSTEMS=="usb", ATTRS{idVendor}=="16c0", ATTRS{idProduct}=="05dc", TAG+="uaccess"
 
+# USBtinyISP
+SUBSYSTEMS=="usb", ATTRS{idVendor}=="1782", ATTRS{idProduct}=="0c9f", TAG+="uaccess"
+
 # ModemManager should ignore the following devices
 # Atmel SAM-BA (Massdrop)
 SUBSYSTEMS=="usb", ATTRS{idVendor}=="03eb", ATTRS{idProduct}=="6124", TAG+="uaccess", ENV{ID_MM_DEVICE_IGNORE}="1"
@@ -72,3 +75,9 @@ KERNEL=="hidraw*", MODE="0660", GROUP="plugdev", TAG+="uaccess", TAG+="udev-acl"
 SUBSYSTEMS=="usb", ATTRS{idVendor}=="03eb", ATTRS{idProduct}=="2067", TAG+="uaccess"
 ## PJRC's HalfKay
 SUBSYSTEMS=="usb", ATTRS{idVendor}=="16c0", ATTRS{idProduct}=="0478", TAG+="uaccess"
+
+# APM32 DFU
+SUBSYSTEMS=="usb", ATTRS{idVendor}=="314b", ATTRS{idProduct}=="0106", TAG+="uaccess"
+
+# GD32V DFU
+SUBSYSTEMS=="usb", ATTRS{idVendor}=="28e9", ATTRS{idProduct}=="0189", TAG+="uaccess"