diff --git a/python/src/trezorlib/cli/__init__.py b/python/src/trezorlib/cli/__init__.py
index 3ba76a67d9..51e6e98c79 100644
--- a/python/src/trezorlib/cli/__init__.py
+++ b/python/src/trezorlib/cli/__init__.py
@@ -26,7 +26,7 @@ from contextlib import contextmanager
 import click
 
 from .. import exceptions, transport, ui
-from ..client import TrezorClient
+from ..client import PROTOCOL_V2, TrezorClient
 from ..messages import Capability
 from ..transport import Transport
 from ..transport.thp.channel_database import get_channel_db
@@ -136,7 +136,7 @@ class TrezorConnection:
         self.passphrase_on_host = passphrase_on_host
         self.script = script
 
-    def get_session(self, derive_cardano: bool = False):
+    def get_session(self, derive_cardano: bool = False, empty_passphrase: bool = False):
         client = self.get_client()
 
         if self.session_id is not None:
@@ -148,10 +148,12 @@ class TrezorConnection:
         if not passphrase_enabled:
             return client.get_session(derive_cardano=derive_cardano)
 
-        # TODO Passphrase empty by default - ???
-        available_on_device = Capability.PassphraseEntry in features.capabilities
-        passphrase = get_passphrase(available_on_device, self.passphrase_on_host)
-        # TODO handle case when PASSPHRASE_ON_DEVICE is returned from get_passphrase func
+        if empty_passphrase:
+            passphrase = ""
+        else:
+            available_on_device = Capability.PassphraseEntry in features.capabilities
+            passphrase = get_passphrase(available_on_device, self.passphrase_on_host)
+            # TODO handle case when PASSPHRASE_ON_DEVICE is returned from get_passphrase func
         if not isinstance(passphrase, str):
             raise RuntimeError("Passphrase must be a str")
         session = client.get_session(
@@ -310,6 +312,25 @@ def with_session(
     return function_with_session
 
 
+def with_default_session(
+    func: "t.Callable[Concatenate[Session, P], R]", derive_cardano: bool = False
+) -> "t.Callable[P, R]":
+
+    @click.pass_obj
+    @functools.wraps(func)
+    def function_with_session(
+        obj: TrezorConnection, *args: "P.args", **kwargs: "P.kwargs"
+    ) -> "R":
+        session = obj.get_session(derive_cardano, empty_passphrase=True)
+        try:
+            return func(session, *args, **kwargs)
+        finally:
+            pass
+            # TODO try end session if not resumed
+
+    return function_with_session
+
+
 def with_management_session(
     func: "t.Callable[Concatenate[Session, P], R]",
 ) -> "t.Callable[P, R]":
@@ -355,7 +376,8 @@ def with_client(
             try:
                 return func(client, *args, **kwargs)
             finally:
-                get_channel_db().save_channel(client.protocol)
+                if client.protocol_version == PROTOCOL_V2:
+                    get_channel_db().save_channel(client.protocol)
                 # if not session_was_resumed:
                 #     try:
                 #         client.end_session()
diff --git a/python/src/trezorlib/cli/benchmark.py b/python/src/trezorlib/cli/benchmark.py
index a7ebab12f7..bef9266a28 100644
--- a/python/src/trezorlib/cli/benchmark.py
+++ b/python/src/trezorlib/cli/benchmark.py
@@ -20,7 +20,7 @@ from typing import TYPE_CHECKING, List, Optional
 import click
 
 from .. import benchmark
-from . import with_session
+from . import with_default_session
 
 if TYPE_CHECKING:
 
@@ -41,7 +41,7 @@ def cli() -> None:
 
 @cli.command()
 @click.argument("pattern", required=False)
-@with_session
+@with_default_session
 def list_names(session: "Session", pattern: Optional[str] = None) -> None:
     """List names of all supported benchmarks"""
     names = list_names_patern(session, pattern)
@@ -54,7 +54,7 @@ def list_names(session: "Session", pattern: Optional[str] = None) -> None:
 
 @cli.command()
 @click.argument("pattern", required=False)
-@with_session
+@with_default_session
 def run(session: "Session", pattern: Optional[str]) -> None:
     """Run benchmark"""
     names = list_names_patern(session, pattern)
diff --git a/python/src/trezorlib/cli/crypto.py b/python/src/trezorlib/cli/crypto.py
index b8fd2cdcb1..1f5be15255 100644
--- a/python/src/trezorlib/cli/crypto.py
+++ b/python/src/trezorlib/cli/crypto.py
@@ -19,7 +19,7 @@ from typing import TYPE_CHECKING, Tuple
 import click
 
 from .. import misc, tools
-from . import ChoiceType, with_session
+from . import ChoiceType, with_default_session
 
 if TYPE_CHECKING:
     from ..transport.session import Session
@@ -42,7 +42,7 @@ def cli() -> None:
 
 @cli.command()
 @click.argument("size", type=int)
-@with_session
+@with_default_session
 def get_entropy(session: "Session", size: int) -> str:
     """Get random bytes from device."""
     return misc.get_entropy(session, size).hex()
@@ -55,7 +55,7 @@ def get_entropy(session: "Session", size: int) -> str:
 )
 @click.argument("key")
 @click.argument("value")
-@with_session
+@with_default_session
 def encrypt_keyvalue(
     session: "Session",
     address: str,
@@ -91,7 +91,7 @@ def encrypt_keyvalue(
 )
 @click.argument("key")
 @click.argument("value")
-@with_session
+@with_default_session
 def decrypt_keyvalue(
     session: "Session",
     address: str,
diff --git a/python/src/trezorlib/cli/fido.py b/python/src/trezorlib/cli/fido.py
index 8d5e5628ba..2071a99fb5 100644
--- a/python/src/trezorlib/cli/fido.py
+++ b/python/src/trezorlib/cli/fido.py
@@ -19,7 +19,7 @@ from typing import TYPE_CHECKING
 import click
 
 from .. import fido
-from . import with_session
+from . import with_default_session
 
 if TYPE_CHECKING:
     from ..transport.session import Session
@@ -40,7 +40,7 @@ def credentials() -> None:
 
 
 @credentials.command(name="list")
-@with_session
+@with_default_session
 def credentials_list(session: "Session") -> None:
     """List all resident credentials on the device."""
     creds = fido.list_credentials(session)
@@ -79,7 +79,7 @@ def credentials_list(session: "Session") -> None:
 
 @credentials.command(name="add")
 @click.argument("hex_credential_id")
-@with_session
+@with_default_session
 def credentials_add(session: "Session", hex_credential_id: str) -> str:
     """Add the credential with the given ID as a resident credential.
 
@@ -92,7 +92,7 @@ def credentials_add(session: "Session", hex_credential_id: str) -> str:
 @click.option(
     "-i", "--index", required=True, type=click.IntRange(0, 99), help="Credential index."
 )
-@with_session
+@with_default_session
 def credentials_remove(session: "Session", index: int) -> str:
     """Remove the resident credential at the given index."""
     return fido.remove_credential(session, index)
@@ -110,14 +110,14 @@ def counter() -> None:
 
 @counter.command(name="set")
 @click.argument("counter", type=int)
-@with_session
+@with_default_session
 def counter_set(session: "Session", counter: int) -> str:
     """Set FIDO/U2F counter value."""
     return fido.set_counter(session, counter)
 
 
 @counter.command(name="get-next")
-@with_session
+@with_default_session
 def counter_get_next(session: "Session") -> int:
     """Get-and-increase value of FIDO/U2F counter.
 
diff --git a/python/src/trezorlib/cli/trezorctl.py b/python/src/trezorlib/cli/trezorctl.py
index 64308ee0cc..1269092941 100755
--- a/python/src/trezorlib/cli/trezorctl.py
+++ b/python/src/trezorlib/cli/trezorctl.py
@@ -54,6 +54,7 @@ from . import (
     tezos,
     with_client,
     with_session,
+    with_default_session,
 )
 
 F = TypeVar("F", bound=Callable)
@@ -328,7 +329,7 @@ def version() -> str:
 @cli.command()
 @click.argument("message")
 @click.option("-b", "--button-protection", is_flag=True)
-@with_session
+@with_default_session
 def ping(session: "Session", message: str, button_protection: bool) -> str:
     """Send ping message."""
 
@@ -362,7 +363,7 @@ def get_session(
                 "Upgrade your firmware to enable session support."
             )
 
-        client.ensure_unlocked()
+        # client.ensure_unlocked()
         session = client.get_session(
             passphrase=passphrase, derive_cardano=derive_cardano
         )
@@ -376,9 +377,9 @@ def get_session(
 @with_session
 def clear_session(session: "Session") -> None:
     """Clear session (remove cached PIN, passphrase, etc.)."""
-    # TODO something like old: return client.clear_session()
-    print("NOT IMPLEMENTED")
-    raise NotImplementedError
+    session.call(messages.LockDevice())
+    session.end()
+    # TODO different behaviour than main, not sure if ok
 
 
 @cli.command()
diff --git a/python/src/trezorlib/client.py b/python/src/trezorlib/client.py
index e7a7b0597f..266ca9f8a8 100644
--- a/python/src/trezorlib/client.py
+++ b/python/src/trezorlib/client.py
@@ -48,6 +48,9 @@ Or visit https://suite.trezor.io/
 
 LOG = logging.getLogger(__name__)
 
+UNKNOWN = -1
+PROTOCOL_V1 = 1
+PROTOCOL_V2 = 2
 
 class TrezorClient:
     button_callback: t.Callable[[Session, t.Any], t.Any] | None = None
@@ -56,7 +59,7 @@ class TrezorClient:
 
     _management_session: Session | None = None
     _features: messages.Features | None = None
-
+    _protocol_version: int
     def __init__(
         self,
         transport: Transport,
@@ -77,6 +80,12 @@ class TrezorClient:
         else:
             self.protocol = protocol
         self.protocol.mapping = self.mapping
+        if isinstance(self.protocol, ProtocolV1):
+            self._protocol_version = PROTOCOL_V1
+        elif isinstance(self.protocol, ProtocolV2):
+            self._protocol_version = PROTOCOL_V2
+        else:
+            self._protocol_version = UNKNOWN
 
     @classmethod
     def resume(
@@ -170,6 +179,10 @@ class TrezorClient:
         assert self._features is not None
         return self._features
 
+    @property
+    def protocol_version(self) -> int:
+        return self._protocol_version
+
     @property
     def model(self) -> models.TrezorModel:
         f = self.features
@@ -196,10 +209,6 @@ class TrezorClient:
         self.protocol.update_features()
         self._features = self.protocol.get_features()
 
-    def ensure_unlocked(self) -> None:
-        # TODO implement
-        raise NotImplementedError
-
     def _get_protocol(self) -> ProtocolAndChannel:
         self.transport.open()
 
diff --git a/python/src/trezorlib/transport/session.py b/python/src/trezorlib/transport/session.py
index efe40ffc0a..9be4083194 100644
--- a/python/src/trezorlib/transport/session.py
+++ b/python/src/trezorlib/transport/session.py
@@ -103,6 +103,8 @@ class SessionV1(Session):
         else:
             session = SessionV1(client, session_id)
         session.button_callback = client.button_callback
+        if session.button_callback is None:
+            session.button_callback = _callback_button
         session.pin_callback = client.pin_callback
         session.passphrase_callback = client.passphrase_callback
         session.passphrase = passphrase