FDS not able to write in SDK 14

[Chris]

Dear all,

I'm struggling writing 32 bytes with FDS in SDK 14.

This is what I do:

Init

(void) fds_register(fds_evt_handler);
fds_init();
while(!is_init) {
    sd_app_evt_wait();
}

Write

fds_record_t        record;
fds_record_desc_t   record_desc = {0};

record.file_id              = FILE_ID;
record.key                  = key;
record.data.p_data        = data;
record.data.length_words      =  (length+3)/ sizeof(uint32_t);
fds_record_write(&record_desc, &record);

I do see that the header is written and on next startup fds_stat returns one more dirty record, but fds_evt_handler is never called with FDS_EVT_WRITE. It is called with FDS_EVT_INIT though, so it seems to basically work. I've read in other posts (mostly concerning older SDKs) that one should check that a soc_evt_handler forwards events to fds_evt_handler, but after

NRF_SDH_SOC_OBSERVER(m_soc_observer, APP_SOC_OBSERVER_PRIO, soc_evt_handler, NULL);

soc_evt_handler is never called.

Any help?

[arthare]

Chris's and Jukka's answer fixed me!  I just want to add my symptoms so this might come up earlier in searches:

• An application run would either never get its FDS_EVT_INIT callback or would get it immediately.
• Each time I started my application, my FDS pages (m_pages in fds.c) would be one state closer to inited.  So I could start->stop->start->stop->start->stop, and eventually they'd hit the `ALREADY_INSTALLED` return in fds_init(), which would get me my `FDS_EVT_INIT` callback and my app would start.
  
  • The fact the pages changed each time I started the app seemed to show that the writes were _happening_, just that some callbacks weren't happening
• Further debugging in `nrf_fstorage_sd.c` (fstorage's softdevice implementation) seemed to show that it never got its `nrf_fstorage_sys_evt_handler` callback, which seemed likely to be needed in order for FDS to eventually get the callback it needed.  Since `nrf_fstorage_sys_evt_handler` is registered with `NRF_SDH_SOC_OBSERVER`, that's what got me on the scent of nrf_sdh_soc, and what led me to this answer.

Fixed for me just by adding nrf_sdh_soc.c to my makefile - I didn't have to add a stub, but I also don't have any optimizations on.  I had missed adding it to my makefile while migrating from SDK 11.0.  Now I'm worried there's other files I've missed...

I'm using Softdevice S332 5.0.0, API 14.2 (17b948a)