feat(core): show blue dot when USB data not connected

core/.changelog.d/2366.added

@@ -0,0 +1 @@
+Show blue dot when USB data pins are not connected

core/embed/extmod/modtrezorio/modtrezorio-poll.h

@@ -24,11 +24,14 @@
 #include "display.h"
 #include "embed/extmod/trezorobj.h"
 
+#define USB_DATA_IFACE (253)
 #define BUTTON_IFACE (254)
 #define TOUCH_IFACE (255)
 #define POLL_READ (0x0000)
 #define POLL_WRITE (0x0100)
 
+extern bool usb_connected_previously;
+
 /// package: trezorio.__init__
 
 /// def poll(ifaces: Iterable[int], list_ref: list, timeout_ms: int) -> bool:
@@ -114,6 +117,14 @@ STATIC mp_obj_t mod_trezorio_poll(mp_obj_t ifaces, mp_obj_t list_ref,
           ret->items[1] = MP_OBJ_FROM_PTR(tuple);
           return mp_const_true;
         }
+      } else if (iface == USB_DATA_IFACE) {
+        bool usb_connected = usb_configured() == sectrue ? true : false;
+        if (usb_connected != usb_connected_previously) {
+          usb_connected_previously = usb_connected;
+          ret->items[0] = MP_OBJ_NEW_SMALL_INT(i);
+          ret->items[1] = usb_connected ? mp_const_true : mp_const_false;
+          return mp_const_true;
+        }
       }
 #elif defined TREZOR_MODEL_1 || defined TREZOR_MODEL_R
       else if (iface == BUTTON_IFACE) {

core/embed/extmod/modtrezorio/modtrezorio.c

@@ -31,6 +31,9 @@
 #include "touch.h"
 #include "usb.h"
 
+// Whether USB data pins were connected on last check (USB configured)
+__attribute__((unused)) static bool usb_connected_previously = false;
+
 #define CHECK_PARAM_RANGE(value, minimum, maximum)  \
   if (value < minimum || value > maximum) {         \
     mp_raise_ValueError(#value " is out of range"); \
@@ -67,6 +70,8 @@
 /// BUTTON_LEFT: int  # button number of left button
 /// BUTTON_RIGHT: int  # button number of right button
 
+/// USB_CHECK: int # interface id for check of USB data connection
+
 /// WireInterface = Union[HID, WebUSB]
 
 STATIC const mp_rom_map_elem_t mp_module_trezorio_globals_table[] = {
@@ -81,6 +86,8 @@ STATIC const mp_rom_map_elem_t mp_module_trezorio_globals_table[] = {
     {MP_ROM_QSTR(MP_QSTR_TOUCH_START), MP_ROM_INT((TOUCH_START >> 24) & 0xFFU)},
     {MP_ROM_QSTR(MP_QSTR_TOUCH_MOVE), MP_ROM_INT((TOUCH_MOVE >> 24) & 0xFFU)},
     {MP_ROM_QSTR(MP_QSTR_TOUCH_END), MP_ROM_INT((TOUCH_END >> 24) & 0xFFU)},
+
+    {MP_ROM_QSTR(MP_QSTR_USB_CHECK), MP_ROM_INT(USB_DATA_IFACE)},
 #elif defined TREZOR_MODEL_1 || defined TREZOR_MODEL_R
     {MP_ROM_QSTR(MP_QSTR_BUTTON), MP_ROM_INT(BUTTON_IFACE)},
     {MP_ROM_QSTR(MP_QSTR_BUTTON_PRESSED),

core/embed/extmod/modtrezorutils/modtrezorutils.c

@@ -34,6 +34,7 @@
 #include "blake2s.h"
 #include "common.h"
 #include "flash.h"
+#include "usb.h"
 
 #ifndef TREZOR_EMULATOR
 #include "image.h"
@@ -221,6 +222,17 @@ STATIC mp_obj_t mod_trezorutils_reboot_to_bootloader() {
 STATIC MP_DEFINE_CONST_FUN_OBJ_0(mod_trezorutils_reboot_to_bootloader_obj,
                                  mod_trezorutils_reboot_to_bootloader);
 
+/// def usb_data_connected() -> bool:
+///     """
+///     Returns whether USB has been enumerated/configured
+///     (and is not just connected by cable without data pins)
+///     """
+STATIC mp_obj_t mod_trezorutils_usb_data_connected() {
+  return usb_configured() == sectrue ? mp_const_true : mp_const_false;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_0(mod_trezorutils_usb_data_connected_obj,
+                                 mod_trezorutils_usb_data_connected);
+
 STATIC mp_obj_str_t mod_trezorutils_revision_obj = {
     {&mp_type_bytes}, 0, sizeof(SCM_REVISION) - 1, (const byte *)SCM_REVISION};
 
@@ -243,6 +255,8 @@ STATIC const mp_rom_map_elem_t mp_module_trezorutils_globals_table[] = {
      MP_ROM_PTR(&mod_trezorutils_firmware_vendor_obj)},
     {MP_ROM_QSTR(MP_QSTR_reboot_to_bootloader),
      MP_ROM_PTR(&mod_trezorutils_reboot_to_bootloader_obj)},
+    {MP_ROM_QSTR(MP_QSTR_usb_data_connected),
+     MP_ROM_PTR(&mod_trezorutils_usb_data_connected_obj)},
     // various built-in constants
     {MP_ROM_QSTR(MP_QSTR_SCM_REVISION),
      MP_ROM_PTR(&mod_trezorutils_revision_obj)},

core/embed/trezorhal/usb.c

@@ -152,6 +152,15 @@ void usb_start(void) { USBD_Start(&usb_dev_handle); }
 
 void usb_stop(void) { USBD_Stop(&usb_dev_handle); }
 
+secbool usb_configured(void) {
+  USBD_HandleTypeDef *pdev = &usb_dev_handle;
+  if (pdev->dev_state == USBD_STATE_CONFIGURED) {
+    return sectrue;
+  }
+
+  return secfalse;
+}
+
 /*
  * Utility functions for USB interfaces
  */

core/embed/trezorhal/usb.h

@@ -143,5 +143,6 @@ void usb_init(const usb_dev_info_t *dev_info);
 void usb_deinit(void);
 void usb_start(void);
 void usb_stop(void);
+secbool usb_configured(void);
 
 #endif

core/embed/unix/usb.c

@@ -25,6 +25,7 @@
 #include <sys/poll.h>
 #include <sys/socket.h>
 #include <time.h>
+#include <unistd.h>
 
 #include "touch.h"
 #include "usb.h"
@@ -249,3 +250,11 @@ int usb_webusb_write(uint8_t iface_num, const uint8_t *buf, uint32_t len) {
 void pendsv_kbd_intr(void) {}
 
 void mp_hal_set_vcp_iface(int iface_num) {}
+
+secbool usb_configured(void) {
+  if (access("/var/tmp/trezor.usb_data_disconnected", F_OK) == 0) {
+    return secfalse;
+  }
+
+  return sectrue;
+}

core/mocks/generated/trezorio/__init__.pyi

@@ -202,4 +202,5 @@ BUTTON_PRESSED: int  # button down event
 BUTTON_RELEASED: int  # button up event
 BUTTON_LEFT: int  # button number of left button
 BUTTON_RIGHT: int  # button number of right button
+USB_CHECK: int # interface id for check of USB data connection
 WireInterface = Union[HID, WebUSB]

core/mocks/generated/trezorutils.pyi

@@ -65,6 +65,14 @@ def reboot_to_bootloader() -> None:
     """
     Reboots to bootloader.
     """
+
+
+# extmod/modtrezorutils/modtrezorutils.c
+def usb_data_connected() -> bool:
+    """
+    Returns whether USB has been enumerated/configured
+    (and is not just connected by cable without data pins)
+    """
 SCM_REVISION: bytes
 VERSION_MAJOR: int
 VERSION_MINOR: int

core/src/apps/homescreen/homescreen.py

@@ -1,10 +1,11 @@
 import utime
 from micropython import const
+from typing import Tuple
 
 import storage
 import storage.cache
 import storage.device
-from trezor import config, ui, utils
+from trezor import config, io, loop, ui, utils
 from trezor.ui.loader import Loader, LoaderNeutral
 
 from apps.base import lock_device
@@ -25,6 +26,7 @@ class Homescreen(HomescreenBase):
 
     def __init__(self) -> None:
         super().__init__()
+        self.is_connected = False
         if not storage.device.is_initialized():
             self.label = "Go to trezor.io/start"
 
@@ -36,6 +38,17 @@ class Homescreen(HomescreenBase):
         )
         self.touch_ms: int | None = None
 
+    def create_tasks(self) -> Tuple[loop.AwaitableTask, ...]:
+        return super().create_tasks() + (self.usb_checker_task(),)
+
+    async def usb_checker_task(self) -> None:
+        usbcheck = loop.wait(io.USB_CHECK)
+        while True:
+            is_connected = await usbcheck
+            if is_connected != self.is_connected:
+                self.is_connected = is_connected
+                self.set_repaint(True)
+
     def do_render(self) -> None:
         # warning bar on top
         if storage.device.is_initialized() and storage.device.no_backup():
@@ -54,6 +67,9 @@ class Homescreen(HomescreenBase):
         # homescreen with shifted avatar and text on bottom
         # Differs for each model
 
+        if not utils.usb_data_connected():
+            ui.display.bar(0, 0, 8, 8, ui.BLUE)
+
         # TODO: support homescreen avatar change for R and 1
         if utils.MODEL in ("T",):
             ui.display.avatar(48, 48 - 10, self.get_image(), ui.WHITE, ui.BLACK)
@@ -69,6 +85,8 @@ class Homescreen(HomescreenBase):
             ui.WIDTH // 2, label_heights[utils.MODEL], self.label, ui.BOLD, ui.FG, ui.BG
         )
 
+        ui.refresh()
+
     def on_touch_start(self, _x: int, _y: int) -> None:
         if self.loader.start_ms is not None:
             self.loader.start()

core/src/trezor/utils.py

@@ -14,6 +14,7 @@ from trezorutils import (  # noqa: F401
     halt,
     memcpy,
     reboot_to_bootloader,
+    usb_data_connected,
 )
 from typing import TYPE_CHECKING