diff --git a/core/embed/extmod/modtrezorio/modtrezorio-sdcard.h b/core/embed/extmod/modtrezorio/modtrezorio-sdcard.h
index d3564e02c..94edd6af9 100644
--- a/core/embed/extmod/modtrezorio/modtrezorio-sdcard.h
+++ b/core/embed/extmod/modtrezorio/modtrezorio-sdcard.h
@@ -91,7 +91,8 @@ STATIC mp_obj_t mod_trezorio_SDCard_read(mp_obj_t self, mp_obj_t block_num,
   uint32_t block = trezor_obj_get_uint(block_num);
   mp_buffer_info_t bufinfo;
   mp_get_buffer_raise(buf, &bufinfo, MP_BUFFER_WRITE);
-  if (sectrue != sdcard_read_blocks(bufinfo.buf, block, bufinfo.len / SDCARD_BLOCK_SIZE)) {
+  if (sectrue !=
+      sdcard_read_blocks(bufinfo.buf, block, bufinfo.len / SDCARD_BLOCK_SIZE)) {
     mp_raise_OSError(MP_EIO);
   }
   return mp_const_none;
@@ -110,7 +111,8 @@ STATIC mp_obj_t mod_trezorio_SDCard_write(mp_obj_t self, mp_obj_t block_num,
   uint32_t block = trezor_obj_get_uint(block_num);
   mp_buffer_info_t bufinfo;
   mp_get_buffer_raise(buf, &bufinfo, MP_BUFFER_READ);
-  if (sectrue != sdcard_write_blocks(bufinfo.buf, block, bufinfo.len / SDCARD_BLOCK_SIZE)) {
+  if (sectrue != sdcard_write_blocks(bufinfo.buf, block,
+                                     bufinfo.len / SDCARD_BLOCK_SIZE)) {
     mp_raise_OSError(MP_EIO);
   }
   return mp_const_none;
diff --git a/core/mocks/generated/trezorio.py b/core/mocks/generated/trezorio.py
index db6a01a04..8e147d025 100644
--- a/core/mocks/generated/trezorio.py
+++ b/core/mocks/generated/trezorio.py
@@ -115,14 +115,14 @@ class SDCard:
         Returns capacity of the SD card in bytes, or zero if not present.
         """
 
-    def read(self, block_num: int, buf: bytearray) -> bool:
+    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) -> bool:
+    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