diff --git a/extmod/vfs_fat_file.c b/extmod/vfs_fat_file.c
index 75fa2fbd49..1b2bb27f83 100644
--- a/extmod/vfs_fat_file.c
+++ b/extmod/vfs_fat_file.c
@@ -197,6 +197,23 @@ STATIC mp_obj_t file_open(fs_user_mount_t *vfs, const mp_obj_type_t *type, mp_ar
         m_del_obj(pyb_file_obj_t, o);
         mp_raise_OSError(fresult_to_errno_table[res]);
     }
+    // If we're reading, turn on fast seek.
+    if (mode == FA_READ) {
+        // one call to determine how much space we need.
+        DWORD temp_table[2];
+        temp_table[0] = 2;
+        o->fp.cltbl = temp_table;
+        f_lseek(&o->fp, CREATE_LINKMAP);
+        DWORD size = (temp_table[0] + 1) * 2;
+        o->fp.cltbl = m_malloc_maybe(size * sizeof(DWORD), false);
+        if (o->fp.cltbl != NULL) {
+            o->fp.cltbl[0] = size;
+            res = f_lseek(&o->fp, CREATE_LINKMAP);
+            if (res != FR_OK) {
+                o->fp.cltbl = NULL;
+            }
+        }
+    }
 
     // for 'a' mode, we must begin at the end of the file
     if ((mode & FA_OPEN_ALWAYS) != 0) {
diff --git a/lib/oofatfs/ffconf.h b/lib/oofatfs/ffconf.h
index 315101f0e4..214311b4c2 100644
--- a/lib/oofatfs/ffconf.h
+++ b/lib/oofatfs/ffconf.h
@@ -74,7 +74,7 @@
 /* This option switches f_mkfs() function. (0:Disable or 1:Enable) */
 
 
-#define _USE_FASTSEEK   0
+#define _USE_FASTSEEK   1
 /* This option switches fast seek function. (0:Disable or 1:Enable) */
 
 
diff --git a/ports/atmel-samd/boards/hallowing_m0_express/board.c b/ports/atmel-samd/boards/hallowing_m0_express/board.c
index ab166d39be..23b1194138 100644
--- a/ports/atmel-samd/boards/hallowing_m0_express/board.c
+++ b/ports/atmel-samd/boards/hallowing_m0_express/board.c
@@ -94,6 +94,7 @@ void board_init(void) {
         display_init_sequence,
         sizeof(display_init_sequence),
         &pin_PA00);
+    common_hal_displayio_display_set_auto_brightness(display, true);
 }
 
 bool board_requests_safe_mode(void) {
diff --git a/ports/atmel-samd/boards/pyportal/board.c b/ports/atmel-samd/boards/pyportal/board.c
index 3ef079e537..9b05063baf 100644
--- a/ports/atmel-samd/boards/pyportal/board.c
+++ b/ports/atmel-samd/boards/pyportal/board.c
@@ -91,6 +91,7 @@ void board_init(void) {
         display_init_sequence,
         sizeof(display_init_sequence),
         &pin_PB31);
+    common_hal_displayio_display_set_auto_brightness(display, true);
 }
 
 bool board_requests_safe_mode(void) {