python/trezorctl: add warning when initializing a T1 with Shamir

fixes #445

python/CHANGELOG.md

@@ -8,10 +8,11 @@ _At the moment, the project does **not** adhere to [Semantic Versioning](https:/
 
 ## [0.11.5] - Unreleased
 
-[0.11.5]: https://github.com/trezor/trezor-firmware/compare/python/v0.11.3...master
+[0.11.5]: https://github.com/trezor/trezor-firmware/compare/python/v0.11.4...master
 
 ### Added
 
+- trezorctl shows a warning when activating Shamir Backup on T1 [f#445]
 - warnings are emitted when encountering unknown value for a protobuf enum [f#363]
 - debug messages show enum value names instead of raw numbers
 - support for packed repeated encoding in the protobuf decoder
@@ -314,3 +315,4 @@ _At the moment, the project does **not** adhere to [Semantic Versioning](https:/
 [f#363]: https://github.com/trezor/trezor-firmware/issues/363
 [f#411]: https://github.com/trezor/trezor-firmware/issues/411
 [f#420]: https://github.com/trezor/trezor-firmware/issues/420
+[f#445]: https://github.com/trezor/trezor-firmware/issues/445

python/src/trezorlib/cli/trezorctl.py

@@ -530,8 +530,19 @@ def reset_device(
 ):
     if strength:
         strength = int(strength)
+
+    client = connect()
+    if (
+        client.features.model == "1"
+        and backup_type != proto.ResetDeviceBackupType.Bip39
+    ):
+        click.echo(
+            "WARNING: Trezor One currently does not support Shamir backup.\n"
+            "Traditional single-seed backup will be generated instead."
+        )
+
     return device.reset(
-        connect(),
+        client,
         display_random=show_entropy,
         strength=strength,
         passphrase_protection=passphrase_protection,