Arend Van Spriel [off-list ref] wrote:

The firmware uses a mailbox to communicate to the host what is going
on. In the driver we validate the bit received. Various people seen
the following message:

 brcmfmac: brcmf_sdio_hostmail: Unknown mailbox data content: 0x40012

Bit 4 is cause of this message, but this actually indicates the firmware
has halted. Handle this bit by giving a more meaningful error message.

Reviewed-by: Hante Meuleman <redacted>
Reviewed-by: Pieter-Paul Giesberts <redacted>
Reviewed-by: Franky Lin <redacted>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>

Failed to compile:

drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c: In function ‘brcmf_p2p_escan’:
drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c:695:23: error: ‘BRCMF_SCANTYPE_ACTIVE’ undeclared (first use in this function)
  sparams->scan_type = BRCMF_SCANTYPE_ACTIVE;
                       ^
drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c:695:23: note: each undeclared identifier is reported only once for each function it appears in
make[6]: *** [drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.o] Error 1
make[6]: *** Waiting for unfinished jobs....
make[5]: *** [drivers/net/wireless/broadcom/brcm80211/brcmfmac] Error 2
make[4]: *** [drivers/net/wireless/broadcom/brcm80211] Error 2
make[3]: *** [drivers/net/wireless/broadcom] Error 2
make[2]: *** [drivers/net/wireless] Error 2
make[1]: *** [drivers/net] Error 2
make: *** [drivers] Error 2

7 patches set to Changes Requested.

9948825 [1/7] brcmfmac: handle FWHALT mailbox indication
9948831 [2/7] brcmfmac: disable packet filtering in promiscuous mode
9948829 [3/7] brcmfmac: cleanup brcmf_cfg80211_escan() function
9948833 [4/7] brcmfmac: use msecs_to_jiffies() instead of calculation using HZ
9948827 [5/7] brcmfmac: get rid of brcmf_cfg80211_escan() function
9948823 [6/7] brcmfmac: get rid of struct brcmf_cfg80211_info::active_scan field
9948835 [7/7] brcmfmac: move configuration of probe request IEs

-- 
https://patchwork.kernel.org/patch/9948825/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches