diff --git a/core/embed/extmod/modtrezorio/modtrezorio-fatfs.h b/core/embed/extmod/modtrezorio/modtrezorio-fatfs.h
index 4d2e8745bc..fbd3fb1e89 100644
--- a/core/embed/extmod/modtrezorio/modtrezorio-fatfs.h
+++ b/core/embed/extmod/modtrezorio/modtrezorio-fatfs.h
@@ -27,9 +27,9 @@
 #include "sdcard.h"
 // clang-format on
 
-DSTATUS disk_initialize(BYTE pdrv) {
-  return disk_status(pdrv);
-}
+/// package: trezorio.__init__
+
+DSTATUS disk_initialize(BYTE pdrv) { return disk_status(pdrv); }
 
 DSTATUS disk_status(BYTE pdrv) {
   return (sectrue == sdcard_is_present()) ? 0 : (STA_NOINIT | STA_NODISK);
diff --git a/core/embed/extmod/modtrezorio/modtrezorio-flash.h b/core/embed/extmod/modtrezorio/modtrezorio-flash.h
index 1d15ab1877..3f906b906f 100644
--- a/core/embed/extmod/modtrezorio/modtrezorio-flash.h
+++ b/core/embed/extmod/modtrezorio/modtrezorio-flash.h
@@ -21,6 +21,8 @@
 
 #include "embed/extmod/trezorobj.h"
 
+/// package: trezorio.__init__
+
 /// class FlashOTP:
 ///     """
 ///     """
diff --git a/core/embed/extmod/modtrezorio/modtrezorio-hid.h b/core/embed/extmod/modtrezorio/modtrezorio-hid.h
index 28761e40e3..9acabb0933 100644
--- a/core/embed/extmod/modtrezorio/modtrezorio-hid.h
+++ b/core/embed/extmod/modtrezorio/modtrezorio-hid.h
@@ -17,6 +17,8 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+/// package: trezorio.__init__
+
 /// class HID:
 ///     """
 ///     USB HID interface configuration.
diff --git a/core/embed/extmod/modtrezorio/modtrezorio-poll.h b/core/embed/extmod/modtrezorio/modtrezorio-poll.h
index 39812c970d..ba250f78ea 100644
--- a/core/embed/extmod/modtrezorio/modtrezorio-poll.h
+++ b/core/embed/extmod/modtrezorio/modtrezorio-poll.h
@@ -26,6 +26,8 @@
 #define POLL_READ (0x0000)
 #define POLL_WRITE (0x0100)
 
+/// package: trezorio.__init__
+
 /// def poll(ifaces: Iterable[int], list_ref: List, timeout_us: int) -> bool:
 ///     """
 ///     Wait until one of `ifaces` is ready to read or write (using masks
diff --git a/core/embed/extmod/modtrezorio/modtrezorio-sbu.h b/core/embed/extmod/modtrezorio/modtrezorio-sbu.h
index e2c1e515a9..623f1b865b 100644
--- a/core/embed/extmod/modtrezorio/modtrezorio-sbu.h
+++ b/core/embed/extmod/modtrezorio/modtrezorio-sbu.h
@@ -19,6 +19,8 @@
 
 #include "sbu.h"
 
+/// package: trezorio.__init__
+
 /// class SBU:
 ///     """
 ///     """
diff --git a/core/embed/extmod/modtrezorio/modtrezorio-usb.h b/core/embed/extmod/modtrezorio/modtrezorio-usb.h
index 042f1f8361..fff2427e17 100644
--- a/core/embed/extmod/modtrezorio/modtrezorio-usb.h
+++ b/core/embed/extmod/modtrezorio/modtrezorio-usb.h
@@ -24,6 +24,8 @@ enum {
   USB_OPENED = 1,
 };
 
+/// package: trezorio.__init__
+
 /// class USB:
 ///     """
 ///     USB device configuration.
diff --git a/core/embed/extmod/modtrezorio/modtrezorio-vcp.h b/core/embed/extmod/modtrezorio/modtrezorio-vcp.h
index 110999fee5..2253e28578 100644
--- a/core/embed/extmod/modtrezorio/modtrezorio-vcp.h
+++ b/core/embed/extmod/modtrezorio/modtrezorio-vcp.h
@@ -19,6 +19,8 @@
 
 void pendsv_kbd_intr(void);
 
+/// package: trezorio.__init__
+
 /// class VCP:
 ///     """
 ///     USB VCP interface configuration.
diff --git a/core/embed/extmod/modtrezorio/modtrezorio-webusb.h b/core/embed/extmod/modtrezorio/modtrezorio-webusb.h
index c698bc0da2..55f07cc399 100644
--- a/core/embed/extmod/modtrezorio/modtrezorio-webusb.h
+++ b/core/embed/extmod/modtrezorio/modtrezorio-webusb.h
@@ -17,6 +17,8 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+/// package: trezorio.__init__
+
 /// class WebUSB:
 ///     """
 ///     USB WebUSB interface configuration.
diff --git a/core/embed/extmod/modtrezorio/modtrezorio.c b/core/embed/extmod/modtrezorio/modtrezorio.c
index 6e5f01eac2..a0595f8ee0 100644
--- a/core/embed/extmod/modtrezorio/modtrezorio.c
+++ b/core/embed/extmod/modtrezorio/modtrezorio.c
@@ -47,6 +47,8 @@
 #include "modtrezorio-usb.h"
 // clang-format on
 
+/// package: trezorio.__init__
+
 /// POLL_READ: int  # wait until interface is readable and return read data
 /// POLL_WRITE: int  # wait until interface is writable
 ///
@@ -66,7 +68,7 @@ STATIC const mp_rom_map_elem_t mp_module_trezorio_globals_table[] = {
 
     {MP_ROM_QSTR(MP_QSTR_SBU), MP_ROM_PTR(&mod_trezorio_SBU_type)},
 
-    {MP_ROM_QSTR(MP_QSTR_SDCard), MP_ROM_PTR(&mod_trezorio_SDCard_type)},
+    {MP_ROM_QSTR(MP_QSTR_sdcard), MP_ROM_PTR(&mod_trezorio_sdcard_module)},
 
     {MP_ROM_QSTR(MP_QSTR_USB), MP_ROM_PTR(&mod_trezorio_USB_type)},
     {MP_ROM_QSTR(MP_QSTR_HID), MP_ROM_PTR(&mod_trezorio_HID_type)},
diff --git a/core/mocks/generated/trezorio.pyi b/core/mocks/generated/trezorio/__init__.pyi
similarity index 85%
rename from core/mocks/generated/trezorio.pyi
rename to core/mocks/generated/trezorio/__init__.pyi
index 27db7ac0b3..70312c0417 100644
--- a/core/mocks/generated/trezorio.pyi
+++ b/core/mocks/generated/trezorio/__init__.pyi
@@ -220,46 +220,6 @@ class SBU:
         """
 
 
-# extmod/modtrezorio/modtrezorio-sdcard.h
-class SDCard:
-    """
-    """
-
-    def __init__(self) -> None:
-        """
-        """
-
-    def present(self) -> bool:
-        """
-        Returns True if SD card is detected, False otherwise.
-        """
-
-    def power(self, state: bool) -> bool:
-        """
-        Power on or power off the SD card interface.
-        Returns True if in case of success, False otherwise.
-        """
-
-    def capacity(self) -> int:
-        """
-        Returns capacity of the SD card in bytes, or zero if not present.
-        """
-
-    def read(self, block_num: int, buf: bytearray) -> None:
-        """
-        Reads blocks starting with block_num from the SD card into buf.
-        Number of bytes read is length of buf rounded down to multiply of
-        SDCARD_BLOCK_SIZE. Returns True if in case of success, False otherwise.
-        """
-
-    def write(self, block_num: int, buf: bytes) -> None:
-        """
-        Writes blocks starting with block_num from buf to the SD card.
-        Number of bytes written is length of buf rounded down to multiply of
-        SDCARD_BLOCK_SIZE. Returns True if in case of success, False otherwise.
-        """
-
-
 # extmod/modtrezorio/modtrezorio-usb.h
 class USB:
     """
diff --git a/core/mocks/generated/trezorio/sdcard.pyi b/core/mocks/generated/trezorio/sdcard.pyi
new file mode 100644
index 0000000000..b6765a7c5b
--- /dev/null
+++ b/core/mocks/generated/trezorio/sdcard.pyi
@@ -0,0 +1,50 @@
+from typing import *
+BLOCK_SIZE: int  # size of SD card block
+
+
+# extmod/modtrezorio/modtrezorio-sdcard.h
+def is_present() -> bool:
+    """
+    Returns True if SD card is detected, False otherwise.
+    """
+
+
+# extmod/modtrezorio/modtrezorio-sdcard.h
+def power_on() -> None:
+    """
+    Power on the SD card interface.
+    Raises OSError if the SD card cannot be powered on, e.g., when there
+    is no SD card inserted.
+    """
+
+
+# extmod/modtrezorio/modtrezorio-sdcard.h
+def power_off() -> None:
+    """
+    Power off the SD card interface.
+    """
+
+
+# extmod/modtrezorio/modtrezorio-sdcard.h
+def capacity() -> int:
+    """
+    Returns capacity of the SD card in bytes, or zero if not present.
+    """
+
+
+# extmod/modtrezorio/modtrezorio-sdcard.h
+def read(block_num: int, buf: bytearray) -> None:
+    """
+    Reads blocks starting with block_num from the SD card into buf.
+    Number of bytes read is length of buf rounded down to multiply of
+    SDCARD_BLOCK_SIZE. Returns True if in case of success, False otherwise.
+    """
+
+
+# extmod/modtrezorio/modtrezorio-sdcard.h
+def write(block_num: int, buf: bytes) -> None:
+    """
+    Writes blocks starting with block_num from buf to the SD card.
+    Number of bytes written is length of buf rounded down to multiply of
+    SDCARD_BLOCK_SIZE. Returns True if in case of success, False otherwise.
+    """