rp2: Enable VfsFat class for FAT filesystem support.

Allows interfacing with SD cards, for example.

ports/rp2/CMakeLists.txt

@@ -51,6 +51,7 @@ set(SOURCE_DRIVERS
 )
 
 set(SOURCE_PORT
+    fatfs_port.c
     machine_adc.c
     machine_i2c.c
     machine_pin.c

ports/rp2/fatfs_port.c

@@ -0,0 +1,34 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2013, 2014 Damien P. George
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "lib/oofatfs/ff.h"
+#include "hardware/rtc.h"
+
+MP_WEAK DWORD get_fattime(void) {
+    datetime_t t;
+    rtc_get_datetime(&t);
+    return ((2000 + t.year - 1980) << 25) | ((t.month) << 21) | ((t.day) << 16) | ((t.hour) << 11) | ((t.min) << 5) | (t.sec / 2);
+}

ports/rp2/mpconfigport.h

@@ -118,6 +118,12 @@
 #define MICROPY_PY_FRAMEBUF                     (1)
 #define MICROPY_VFS                             (1)
 #define MICROPY_VFS_LFS2                        (1)
+#define MICROPY_VFS_FAT                         (1)
+
+// fatfs configuration
+#define MICROPY_FATFS_ENABLE_LFN                (1)
+#define MICROPY_FATFS_LFN_CODE_PAGE             437 /* 1=SFN/ANSI 437=LFN/U.S.(OEM) */
+#define MICROPY_FATFS_RPATH                     (2)
 
 // Use VfsLfs2's types for fileio/textio
 #define mp_type_fileio mp_type_vfs_lfs2_fileio