diff --git a/pkg/spiffs/Makefile b/pkg/spiffs/Makefile
index d40ea98d32..ee77abd5eb 100644
--- a/pkg/spiffs/Makefile
+++ b/pkg/spiffs/Makefile
@@ -1,6 +1,6 @@
 PKG_NAME=spiffs
 PKG_URL=https://github.com/pellepl/spiffs.git
-PKG_VERSION=39937743fbbec4b82308ee08332bf9180408d23b
+PKG_VERSION=287148c46587089c4543a21eef2d6e9e14b88364
 PKG_BUILDDIR ?= $(PKGDIRBASE)/$(PKG_NAME)
 
 CFLAGS += -std=c11
diff --git a/pkg/spiffs/include/spiffs_config.h b/pkg/spiffs/include/spiffs_config.h
index 892b271df2..c9a86109f9 100644
--- a/pkg/spiffs/include/spiffs_config.h
+++ b/pkg/spiffs/include/spiffs_config.h
@@ -53,19 +53,57 @@ extern "C" {
 
 // Set generic spiffs debug output call.
 #ifndef SPIFFS_DBG
-#define SPIFFS_DBG(...) //DEBUG(__VA_ARGS__)
+#define SPIFFS_DBG(...) //printf(_f, ## __VA_ARGS__)
 #endif
 // Set spiffs debug output call for garbage collecting.
 #ifndef SPIFFS_GC_DBG
-#define SPIFFS_GC_DBG(...) //DEBUG(__VA_ARGS__)
+#define SPIFFS_GC_DBG(...) //printf(_f, ## __VA_ARGS__)
 #endif
 // Set spiffs debug output call for caching.
 #ifndef SPIFFS_CACHE_DBG
-#define SPIFFS_CACHE_DBG(...) //DEBUG(__VA_ARGS__)
+#define SPIFFS_CACHE_DBG(...) //printf(_f, ## __VA_ARGS__)
 #endif
 // Set spiffs debug output call for system consistency checks.
 #ifndef SPIFFS_CHECK_DBG
-#define SPIFFS_CHECK_DBG(...) //DEBUG(__VA_ARGS__)
+#define SPIFFS_CHECK_DBG(...) //printf(_f, ## __VA_ARGS__)
+#endif
+// Set spiffs debug output call for all api invocations.
+#ifndef SPIFFS_API_DBG
+#define SPIFFS_API_DBG(...) //printf(_f, ## __VA_ARGS__)
+#endif
+
+// Defines spiffs debug print formatters
+// some general signed number
+#ifndef _SPIPRIi
+#define _SPIPRIi   "%d"
+#endif
+// address
+#ifndef _SPIPRIad
+#define _SPIPRIad  "%08x"
+#endif
+// block
+#ifndef _SPIPRIbl
+#define _SPIPRIbl  "%04x"
+#endif
+// page
+#ifndef _SPIPRIpg
+#define _SPIPRIpg  "%04x"
+#endif
+// span index
+#ifndef _SPIPRIsp
+#define _SPIPRIsp  "%04x"
+#endif
+// file descriptor
+#ifndef _SPIPRIfd
+#define _SPIPRIfd  "%d"
+#endif
+// file object id
+#ifndef _SPIPRIid
+#define _SPIPRIid  "%04x"
+#endif
+// file flags
+#ifndef _SPIPRIfl
+#define _SPIPRIfl  "%02x"
 #endif
 
 // Enable/disable API functions to determine exact number of bytes
@@ -137,6 +175,20 @@ extern "C" {
 #define SPIFFS_OBJ_NAME_LEN             (32)
 #endif
 
+// Maximum length of the metadata associated with an object.
+// Setting to non-zero value enables metadata-related API but also
+// changes the on-disk format, so the change is not backward-compatible.
+//
+// Do note: the meta length must never exceed
+// logical_page_size - (SPIFFS_OBJ_NAME_LEN + 64)
+//
+// This is derived from following:
+// logical_page_size - (SPIFFS_OBJ_NAME_LEN + sizeof(spiffs_page_header) +
+// spiffs_object_ix_header fields + at least some LUT entries)
+#ifndef SPIFFS_OBJ_META_LEN
+#define SPIFFS_OBJ_META_LEN             (0)
+#endif
+
 // Size of buffer allocated on stack used when copying data.
 // Lower value generates more read/writes. No meaning having it bigger
 // than logical page size.
diff --git a/pkg/spiffs/patches/0001-Constify-pointer-for-write-operations.patch b/pkg/spiffs/patches/0001-Constify-pointer-for-write-operations.patch
new file mode 100644
index 0000000000..3b6002de10
--- /dev/null
+++ b/pkg/spiffs/patches/0001-Constify-pointer-for-write-operations.patch
@@ -0,0 +1,203 @@
+From 8721846f8b03ca7aa1d592abd00a0c9a721e11c6 Mon Sep 17 00:00:00 2001
+From: Vincent Dupont <vincent@otakeys.com>
+Date: Mon, 17 Jul 2017 12:42:12 +0200
+Subject: [PATCH] Constify pointer for write operations
+
+---
+ src/spiffs.h           |  6 +++---
+ src/spiffs_cache.c     |  2 +-
+ src/spiffs_hydrogen.c  | 10 +++++-----
+ src/spiffs_nucleus.c   |  6 +++---
+ src/spiffs_nucleus.h   | 18 ++++++++----------
+ src/test/test_spiffs.c |  2 +-
+ 6 files changed, 21 insertions(+), 23 deletions(-)
+
+diff --git a/src/spiffs.h b/src/spiffs.h
+index 534c3df..991aabf 100644
+--- a/src/spiffs.h
++++ b/src/spiffs.h
+@@ -84,7 +84,7 @@ struct spiffs_t;
+ /* spi read call function type */
+ typedef s32_t (*spiffs_read)(struct spiffs_t *fs, u32_t addr, u32_t size, u8_t *dst);
+ /* spi write call function type */
+-typedef s32_t (*spiffs_write)(struct spiffs_t *fs, u32_t addr, u32_t size, u8_t *src);
++typedef s32_t (*spiffs_write)(struct spiffs_t *fs, u32_t addr, u32_t size, const u8_t *src);
+ /* spi erase call function type */
+ typedef s32_t (*spiffs_erase)(struct spiffs_t *fs, u32_t addr, u32_t size);
+ 
+@@ -93,7 +93,7 @@ typedef s32_t (*spiffs_erase)(struct spiffs_t *fs, u32_t addr, u32_t size);
+ /* spi read call function type */
+ typedef s32_t (*spiffs_read)(u32_t addr, u32_t size, u8_t *dst);
+ /* spi write call function type */
+-typedef s32_t (*spiffs_write)(u32_t addr, u32_t size, u8_t *src);
++typedef s32_t (*spiffs_write)(u32_t addr, u32_t size, const u8_t *src);
+ /* spi erase call function type */
+ typedef s32_t (*spiffs_erase)(u32_t addr, u32_t size);
+ #endif // SPIFFS_HAL_CALLBACK_EXTRA
+@@ -468,7 +468,7 @@ s32_t SPIFFS_read(spiffs *fs, spiffs_file fh, void *buf, s32_t len);
+  * @param len           how much to write
+  * @returns number of bytes written, or -1 if error
+  */
+-s32_t SPIFFS_write(spiffs *fs, spiffs_file fh, void *buf, s32_t len);
++s32_t SPIFFS_write(spiffs *fs, spiffs_file fh, const void *buf, s32_t len);
+ 
+ /**
+  * Moves the read/write file offset. Resulting offset is returned or negative if error.
+diff --git a/src/spiffs_cache.c b/src/spiffs_cache.c
+index 37c9d64..e28911d 100644
+--- a/src/spiffs_cache.c
++++ b/src/spiffs_cache.c
+@@ -185,7 +185,7 @@ s32_t spiffs_phys_wr(
+     spiffs_file fh,
+     u32_t addr,
+     u32_t len,
+-    u8_t *src) {
++    const u8_t *src) {
+   (void)fh;
+   spiffs_page_ix pix = SPIFFS_PADDR_TO_PAGE(fs, addr);
+   spiffs_cache *cache = spiffs_get_cache(fs);
+diff --git a/src/spiffs_hydrogen.c b/src/spiffs_hydrogen.c
+index 69e0c22..1114f51 100644
+--- a/src/spiffs_hydrogen.c
++++ b/src/spiffs_hydrogen.c
+@@ -430,22 +430,22 @@ s32_t SPIFFS_read(spiffs *fs, spiffs_file fh, void *buf, s32_t len) {
+ 
+ 
+ #if !SPIFFS_READ_ONLY
+-static s32_t spiffs_hydro_write(spiffs *fs, spiffs_fd *fd, void *buf, u32_t offset, s32_t len) {
++static s32_t spiffs_hydro_write(spiffs *fs, spiffs_fd *fd, const void *buf, u32_t offset, s32_t len) {
+   (void)fs;
+   s32_t res = SPIFFS_OK;
+   s32_t remaining = len;
+   if (fd->size != SPIFFS_UNDEFINED_LEN && offset < fd->size) {
+     s32_t m_len = MIN((s32_t)(fd->size - offset), len);
+-    res = spiffs_object_modify(fd, offset, (u8_t *)buf, m_len);
++    res = spiffs_object_modify(fd, offset, buf, m_len);
+     SPIFFS_CHECK_RES(res);
+     remaining -= m_len;
+-    u8_t *buf_8 = (u8_t *)buf;
++    const u8_t *buf_8 = buf;
+     buf_8 += m_len;
+     buf = buf_8;
+     offset += m_len;
+   }
+   if (remaining > 0) {
+-    res = spiffs_object_append(fd, offset, (u8_t *)buf, remaining);
++    res = spiffs_object_append(fd, offset, buf, remaining);
+     SPIFFS_CHECK_RES(res);
+   }
+   return len;
+@@ -453,7 +453,7 @@ static s32_t spiffs_hydro_write(spiffs *fs, spiffs_fd *fd, void *buf, u32_t offs
+ }
+ #endif // !SPIFFS_READ_ONLY
+ 
+-s32_t SPIFFS_write(spiffs *fs, spiffs_file fh, void *buf, s32_t len) {
++s32_t SPIFFS_write(spiffs *fs, spiffs_file fh, const void *buf, s32_t len) {
+   SPIFFS_API_DBG("%s "_SPIPRIfd " "_SPIPRIi "\n", __func__, fh, len);
+ #if SPIFFS_READ_ONLY
+   (void)fs; (void)fh; (void)buf; (void)len;
+diff --git a/src/spiffs_nucleus.c b/src/spiffs_nucleus.c
+index 12c9de8..301f179 100644
+--- a/src/spiffs_nucleus.c
++++ b/src/spiffs_nucleus.c
+@@ -754,7 +754,7 @@ s32_t spiffs_page_allocate_data(
+     spiffs *fs,
+     spiffs_obj_id obj_id,
+     spiffs_page_header *ph,
+-    u8_t *data,
++    const u8_t *data,
+     u32_t len,
+     u32_t page_offs,
+     u8_t finalize,
+@@ -1195,7 +1195,7 @@ s32_t spiffs_object_open_by_page(
+ #if !SPIFFS_READ_ONLY
+ // Append to object
+ // keep current object index (header) page in fs->work buffer
+-s32_t spiffs_object_append(spiffs_fd *fd, u32_t offset, u8_t *data, u32_t len) {
++s32_t spiffs_object_append(spiffs_fd *fd, u32_t offset, const u8_t *data, u32_t len) {
+   spiffs *fs = fd->fs;
+   s32_t res = SPIFFS_OK;
+   u32_t written = 0;
+@@ -1442,7 +1442,7 @@ s32_t spiffs_object_append(spiffs_fd *fd, u32_t offset, u8_t *data, u32_t len) {
+ #if !SPIFFS_READ_ONLY
+ // Modify object
+ // keep current object index (header) page in fs->work buffer
+-s32_t spiffs_object_modify(spiffs_fd *fd, u32_t offset, u8_t *data, u32_t len) {
++s32_t spiffs_object_modify(spiffs_fd *fd, u32_t offset, const u8_t *data, u32_t len) {
+   spiffs *fs = fd->fs;
+   s32_t res = SPIFFS_OK;
+   u32_t written = 0;
+diff --git a/src/spiffs_nucleus.h b/src/spiffs_nucleus.h
+index 3d77d50..7b89f01 100644
+--- a/src/spiffs_nucleus.h
++++ b/src/spiffs_nucleus.h
+@@ -545,7 +545,7 @@ s32_t spiffs_phys_wr(
+ #endif
+     u32_t addr,
+     u32_t len,
+-    u8_t *src);
++    const u8_t *src);
+ 
+ s32_t spiffs_phys_cpy(
+     spiffs *fs,
+@@ -619,11 +619,10 @@ s32_t spiffs_obj_lu_find_id_and_span_by_phdr(
+ 
+ // ---------------
+ 
+-s32_t spiffs_page_allocate_data(
+-    spiffs *fs,
++s32_t spiffs_page_allocate_data(spiffs *fs,
+     spiffs_obj_id obj_id,
+     spiffs_page_header *ph,
+-    u8_t *data,
++    const u8_t *data,
+     u32_t len,
+     u32_t page_offs,
+     u8_t finalize,
+@@ -696,16 +695,15 @@ s32_t spiffs_object_open_by_page(
+     spiffs_flags flags,
+     spiffs_mode mode);
+ 
+-s32_t spiffs_object_append(
+-    spiffs_fd *fd,
++s32_t spiffs_object_append(spiffs_fd *fd,
+     u32_t offset,
+-    u8_t *data,
++    const u8_t *data,
+     u32_t len);
+ 
+ s32_t spiffs_object_modify(
+     spiffs_fd *fd,
+     u32_t offset,
+-    u8_t *data,
++    const u8_t *data,
+     u32_t len);
+ 
+ s32_t spiffs_object_read(
+@@ -807,8 +805,8 @@ s32_t spiffs_object_index_consistency_check(
+ // checked in test builds, otherwise plain memcpy (unless already defined)
+ #ifdef _SPIFFS_TEST
+ #define _SPIFFS_MEMCPY(__d, __s, __l) do { \
+-    intptr_t __a1 = (intptr_t)((u8_t*)(__s)); \
+-    intptr_t __a2 = (intptr_t)((u8_t*)(__s)+(__l)); \
++    intptr_t __a1 = (intptr_t)((const u8_t*)(__s)); \
++    intptr_t __a2 = (intptr_t)((const u8_t*)(__s)+(__l)); \
+     intptr_t __b1 = (intptr_t)((u8_t*)(__d)); \
+     intptr_t __b2 = (intptr_t)((u8_t*)(__d)+(__l)); \
+     if (__a1 <= __b2 && __b1 <= __a2) { \
+diff --git a/src/test/test_spiffs.c b/src/test/test_spiffs.c
+index 374028a..e96d4de 100644
+--- a/src/test/test_spiffs.c
++++ b/src/test/test_spiffs.c
+@@ -174,7 +174,7 @@ static s32_t _write(
+ #if SPIFFS_HAL_CALLBACK_EXTRA
+     spiffs *fs,
+ #endif
+-    u32_t addr, u32_t size, u8_t *src) {
++    u32_t addr, u32_t size, const u8_t *src) {
+   int i;
+   //printf("wr %08x %i\n", addr, size);
+   if (log_flash_ops) {
+-- 
+2.11.0
+
diff --git a/pkg/spiffs/patches/0001-Use-const-pointer-in-write-functions.patch b/pkg/spiffs/patches/0001-Use-const-pointer-in-write-functions.patch
deleted file mode 100644
index 565faf9d6f..0000000000
--- a/pkg/spiffs/patches/0001-Use-const-pointer-in-write-functions.patch
+++ /dev/null
@@ -1,48 +0,0 @@
-From 95c4806835cf9b049c5af1a42fd49ed7de82947b Mon Sep 17 00:00:00 2001
-From: Vincent Dupont <vincent@otakeys.com>
-Date: Mon, 11 Jul 2016 19:57:31 +0200
-Subject: [PATCH 1/2] Use const pointer in write functions
-
----
- src/spiffs.h          | 2 +-
- src/spiffs_hydrogen.c | 4 ++--
- 2 files changed, 3 insertions(+), 3 deletions(-)
-
-diff --git a/src/spiffs.h b/src/spiffs.h
-index bea90b3..dfe967d 100644
---- a/src/spiffs.h
-+++ b/src/spiffs.h
-@@ -459,7 +459,7 @@ s32_t SPIFFS_read(spiffs *fs, spiffs_file fh, void *buf, s32_t len);
-  * @param len           how much to write
-  * @returns number of bytes written, or -1 if error
-  */
--s32_t SPIFFS_write(spiffs *fs, spiffs_file fh, void *buf, s32_t len);
-+s32_t SPIFFS_write(spiffs *fs, spiffs_file fh, const void *buf, s32_t len);
- 
- /**
-  * Moves the read/write file offset. Resulting offset is returned or negative if error.
-diff --git a/src/spiffs_hydrogen.c b/src/spiffs_hydrogen.c
-index 1cf64ff..8eb3919 100644
---- a/src/spiffs_hydrogen.c
-+++ b/src/spiffs_hydrogen.c
-@@ -411,7 +411,7 @@ s32_t SPIFFS_read(spiffs *fs, spiffs_file fh, void *buf, s32_t len) {
- }
- 
- #if !SPIFFS_READ_ONLY
--static s32_t spiffs_hydro_write(spiffs *fs, spiffs_fd *fd, void *buf, u32_t offset, s32_t len) {
-+static s32_t spiffs_hydro_write(spiffs *fs, spiffs_fd *fd, const void *buf, u32_t offset, s32_t len) {
-   (void)fs;
-   s32_t res = SPIFFS_OK;
-   s32_t remaining = len;
-@@ -434,7 +434,7 @@ static s32_t spiffs_hydro_write(spiffs *fs, spiffs_fd *fd, void *buf, u32_t offs
- }
- #endif // !SPIFFS_READ_ONLY
- 
--s32_t SPIFFS_write(spiffs *fs, spiffs_file fh, void *buf, s32_t len) {
-+s32_t SPIFFS_write(spiffs *fs, spiffs_file fh, const void *buf, s32_t len) {
- #if SPIFFS_READ_ONLY
-   (void)fs; (void)fh; (void)buf; (void)len;
-   return SPIFFS_ERR_RO_NOT_IMPL;
--- 
-2.9.3
-
diff --git a/pkg/spiffs/patches/0002-Use-const-pointer-through-all-write-functions.patch b/pkg/spiffs/patches/0002-Use-const-pointer-through-all-write-functions.patch
deleted file mode 100644
index d5bc913e5e..0000000000
--- a/pkg/spiffs/patches/0002-Use-const-pointer-through-all-write-functions.patch
+++ /dev/null
@@ -1,236 +0,0 @@
-From 3c753304a7366514c86abfba436103b2f37edf15 Mon Sep 17 00:00:00 2001
-From: Vincent Dupont <vincent@otakeys.com>
-Date: Thu, 8 Sep 2016 14:38:18 +0200
-Subject: [PATCH 2/2] Use const pointer through all write functions
-
-HAL API has been updated to use const pointer when writing
----
- src/spiffs.h          |  4 ++--
- src/spiffs_cache.c    |  2 +-
- src/spiffs_hydrogen.c | 18 ++++++++++--------
- src/spiffs_nucleus.c  | 12 ++++++------
- src/spiffs_nucleus.h  |  8 ++++----
- 5 files changed, 23 insertions(+), 21 deletions(-)
-
-diff --git a/src/spiffs.h b/src/spiffs.h
-index dfe967d..8a42868 100644
---- a/src/spiffs.h
-+++ b/src/spiffs.h
-@@ -81,7 +81,7 @@ struct spiffs_t;
- /* spi read call function type */
- typedef s32_t (*spiffs_read)(struct spiffs_t *fs, u32_t addr, u32_t size, u8_t *dst);
- /* spi write call function type */
--typedef s32_t (*spiffs_write)(struct spiffs_t *fs, u32_t addr, u32_t size, u8_t *src);
-+typedef s32_t (*spiffs_write)(struct spiffs_t *fs, u32_t addr, u32_t size, const u8_t *src);
- /* spi erase call function type */
- typedef s32_t (*spiffs_erase)(struct spiffs_t *fs, u32_t addr, u32_t size);
- 
-@@ -90,7 +90,7 @@ typedef s32_t (*spiffs_erase)(struct spiffs_t *fs, u32_t addr, u32_t size);
- /* spi read call function type */
- typedef s32_t (*spiffs_read)(u32_t addr, u32_t size, u8_t *dst);
- /* spi write call function type */
--typedef s32_t (*spiffs_write)(u32_t addr, u32_t size, u8_t *src);
-+typedef s32_t (*spiffs_write)(u32_t addr, u32_t size, const u8_t *src);
- /* spi erase call function type */
- typedef s32_t (*spiffs_erase)(u32_t addr, u32_t size);
- #endif // SPIFFS_HAL_CALLBACK_EXTRA
-diff --git a/src/spiffs_cache.c b/src/spiffs_cache.c
-index b508ad5..65f8cd2 100644
---- a/src/spiffs_cache.c
-+++ b/src/spiffs_cache.c
-@@ -183,7 +183,7 @@ s32_t spiffs_phys_wr(
-     spiffs_file fh,
-     u32_t addr,
-     u32_t len,
--    u8_t *src) {
-+    const u8_t *src) {
-   (void)fh;
-   spiffs_page_ix pix = SPIFFS_PADDR_TO_PAGE(fs, addr);
-   spiffs_cache *cache = spiffs_get_cache(fs);
-diff --git a/src/spiffs_hydrogen.c b/src/spiffs_hydrogen.c
-index 8eb3919..b2c3d92 100644
---- a/src/spiffs_hydrogen.c
-+++ b/src/spiffs_hydrogen.c
-@@ -417,7 +417,7 @@ static s32_t spiffs_hydro_write(spiffs *fs, spiffs_fd *fd, const void *buf, u32_
-   s32_t remaining = len;
-   if (fd->size != SPIFFS_UNDEFINED_LEN && offset < fd->size) {
-     s32_t m_len = MIN((s32_t)(fd->size - offset), len);
--    res = spiffs_object_modify(fd, offset, (u8_t *)buf, m_len);
-+    res = spiffs_object_modify(fd, offset, buf, m_len);
-     SPIFFS_CHECK_RES(res);
-     remaining -= m_len;
-     u8_t *buf_8 = (u8_t *)buf;
-@@ -426,7 +426,7 @@ static s32_t spiffs_hydro_write(spiffs *fs, spiffs_fd *fd, const void *buf, u32_
-     offset += m_len;
-   }
-   if (remaining > 0) {
--    res = spiffs_object_append(fd, offset, (u8_t *)buf, remaining);
-+    res = spiffs_object_append(fd, offset, buf, remaining);
-     SPIFFS_CHECK_RES(res);
-   }
-   return len;
-@@ -499,7 +499,7 @@ s32_t SPIFFS_write(spiffs *fs, spiffs_file fh, const void *buf, s32_t len) {
-               spiffs_get_cache_page(fs, spiffs_get_cache(fs), fd->cache_page->ix),
-               fd->cache_page->offset, fd->cache_page->size);
-           spiffs_cache_fd_release(fs, fd->cache_page);
--          SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
-+          SPIFFS_API_CHECK_RES(fs, res);
-         } else {
-           // writing within cache
-           alloc_cpage = 0;
-@@ -530,7 +530,7 @@ s32_t SPIFFS_write(spiffs *fs, spiffs_file fh, const void *buf, s32_t len) {
-         return len;
-       } else {
-         res = spiffs_hydro_write(fs, fd, buf, offset, len);
--        SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
-+        SPIFFS_API_CHECK_RES(fs, res);
-         fd->fdoffset += len;
-         SPIFFS_UNLOCK(fs);
-         return res;
-@@ -553,7 +553,7 @@ s32_t SPIFFS_write(spiffs *fs, spiffs_file fh, const void *buf, s32_t len) {
- #endif
- 
-   res = spiffs_hydro_write(fs, fd, buf, offset, len);
--  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
-+  SPIFFS_API_CHECK_RES(fs, res);
-   fd->fdoffset += len;
- 
-   SPIFFS_UNLOCK(fs);
-@@ -571,7 +571,7 @@ s32_t SPIFFS_lseek(spiffs *fs, spiffs_file fh, s32_t offs, int whence) {
-   s32_t res;
-   fh = SPIFFS_FH_UNOFFS(fs, fh);
-   res = spiffs_fd_get(fs, fh, &fd);
--  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
-+  SPIFFS_API_CHECK_RES(fs, res);
- 
- #if SPIFFS_CACHE_WR
-   spiffs_fflush_cache(fs, fh);
-@@ -917,7 +917,7 @@ static s32_t spiffs_read_dir_v(
-   if (res != SPIFFS_OK) return res;
-   if ((obj_id & SPIFFS_OBJ_ID_IX_FLAG) &&
-       objix_hdr.p_hdr.span_ix == 0 &&
--      (objix_hdr.p_hdr.flags & (SPIFFS_PH_FLAG_DELET | SPIFFS_PH_FLAG_FINAL | SPIFFS_PH_FLAG_IXDELE)) ==
-+      (objix_hdr.p_hdr.flags& (SPIFFS_PH_FLAG_DELET | SPIFFS_PH_FLAG_FINAL | SPIFFS_PH_FLAG_IXDELE)) ==
-           (SPIFFS_PH_FLAG_DELET | SPIFFS_PH_FLAG_IXDELE)) {
-     struct spiffs_dirent *e = (struct spiffs_dirent*)user_var_p;
-     e->obj_id = obj_id;
-@@ -927,6 +927,7 @@ static s32_t spiffs_read_dir_v(
-     e->pix = pix;
-     return SPIFFS_OK;
-   }
-+
-   return SPIFFS_VIS_COUNTINUE;
- }
- 
-@@ -1305,10 +1306,11 @@ s32_t SPIFFS_vis(spiffs *fs) {
-   spiffs_printf("free_blocks: %i\n", fs->free_blocks);
-   spiffs_printf("page_alloc:  %i\n", fs->stats_p_allocated);
-   spiffs_printf("page_delet:  %i\n", fs->stats_p_deleted);
--  SPIFFS_UNLOCK(fs);
-   u32_t total, used;
-   SPIFFS_info(fs, &total, &used);
-   spiffs_printf("used:        %i of %i\n", used, total);
-+
-+  SPIFFS_UNLOCK(fs);
-   return res;
- }
- #endif
-diff --git a/src/spiffs_nucleus.c b/src/spiffs_nucleus.c
-index 35fe0d4..625d036 100644
---- a/src/spiffs_nucleus.c
-+++ b/src/spiffs_nucleus.c
-@@ -73,7 +73,7 @@ s32_t spiffs_phys_wr(
-     spiffs *fs,
-     u32_t addr,
-     u32_t len,
--    u8_t *src) {
-+    const u8_t *src) {
-   return SPIFFS_HAL_WRITE(fs, addr, len, src);
- }
- 
-@@ -142,7 +142,7 @@ s32_t spiffs_obj_lu_find_entry_visitor(
-   int entries_per_page = (SPIFFS_CFG_LOG_PAGE_SZ(fs) / sizeof(spiffs_obj_id));
- 
-   // wrap initial
--  if (cur_entry > (int)SPIFFS_OBJ_LOOKUP_MAX_ENTRIES(fs) - 1) {
-+  if (cur_entry >= (int)SPIFFS_OBJ_LOOKUP_MAX_ENTRIES(fs) - 1) {
-     cur_entry = 0;
-     cur_block++;
-     cur_block_addr = cur_block * SPIFFS_CFG_LOG_BLOCK_SZ(fs);
-@@ -467,7 +467,7 @@ s32_t spiffs_obj_lu_find_free(
-       SPIFFS_OBJ_ID_FREE, block_ix, lu_entry);
-   if (res == SPIFFS_OK) {
-     fs->free_cursor_block_ix = *block_ix;
--    fs->free_cursor_obj_lu_entry = (*lu_entry) + 1;
-+    fs->free_cursor_obj_lu_entry = *lu_entry;
-     if (*lu_entry == 0) {
-       fs->free_blocks--;
-     }
-@@ -754,7 +754,7 @@ s32_t spiffs_page_allocate_data(
-     spiffs *fs,
-     spiffs_obj_id obj_id,
-     spiffs_page_header *ph,
--    u8_t *data,
-+    const u8_t *data,
-     u32_t len,
-     u32_t page_offs,
-     u8_t finalize,
-@@ -1155,7 +1155,7 @@ s32_t spiffs_object_open_by_page(
- #if !SPIFFS_READ_ONLY
- // Append to object
- // keep current object index (header) page in fs->work buffer
--s32_t spiffs_object_append(spiffs_fd *fd, u32_t offset, u8_t *data, u32_t len) {
-+s32_t spiffs_object_append(spiffs_fd *fd, u32_t offset, const u8_t *data, u32_t len) {
-   spiffs *fs = fd->fs;
-   s32_t res = SPIFFS_OK;
-   u32_t written = 0;
-@@ -1402,7 +1402,7 @@ s32_t spiffs_object_append(spiffs_fd *fd, u32_t offset, u8_t *data, u32_t len) {
- #if !SPIFFS_READ_ONLY
- // Modify object
- // keep current object index (header) page in fs->work buffer
--s32_t spiffs_object_modify(spiffs_fd *fd, u32_t offset, u8_t *data, u32_t len) {
-+s32_t spiffs_object_modify(spiffs_fd *fd, u32_t offset, const u8_t *data, u32_t len) {
-   spiffs *fs = fd->fs;
-   s32_t res = SPIFFS_OK;
-   u32_t written = 0;
-diff --git a/src/spiffs_nucleus.h b/src/spiffs_nucleus.h
-index 0fa1cb3..2e6afa1 100644
---- a/src/spiffs_nucleus.h
-+++ b/src/spiffs_nucleus.h
-@@ -532,7 +532,7 @@ s32_t spiffs_phys_wr(
- #endif
-     u32_t addr,
-     u32_t len,
--    u8_t *src);
-+    const u8_t *src);
- 
- s32_t spiffs_phys_cpy(
-     spiffs *fs,
-@@ -610,7 +610,7 @@ s32_t spiffs_page_allocate_data(
-     spiffs *fs,
-     spiffs_obj_id obj_id,
-     spiffs_page_header *ph,
--    u8_t *data,
-+    const u8_t *data,
-     u32_t len,
-     u32_t page_offs,
-     u8_t finalize,
-@@ -684,13 +684,13 @@ s32_t spiffs_object_open_by_page(
- s32_t spiffs_object_append(
-     spiffs_fd *fd,
-     u32_t offset,
--    u8_t *data,
-+    const u8_t *data,
-     u32_t len);
- 
- s32_t spiffs_object_modify(
-     spiffs_fd *fd,
-     u32_t offset,
--    u8_t *data,
-+    const u8_t *data,
-     u32_t len);
- 
- s32_t spiffs_object_read(
--- 
-2.9.3
-