Re: [PATCH] brcmfmac: firmware: Fix firmware loading

[Arend van Spriel <arend.vanspriel@broadcom.com>]

On 04-08-2021 01:27, Linus Walleij wrote:
> The patch that would first try the board-specific firmware
> had a bug because the fallback would not be called: the
> asynchronous interface is used meaning request_firmware_nowait()
> returns 0 immediately.
> 
> Harden the firmware loading like this:
> 
> - If we cannot build an alt_path (like if no board_type is
>    specified) just request the first firmware without any
>    suffix, like in the past.
> 
> - If the lookup of a board specific firmware fails, we get
>    a NULL fw in the async callback, so just try again without
>    the alt_path. Use a static variable to check that we do not
>    try this indefinitely.
> 
> - Rename the brcm_fw_request_done to brcm_fw_request_done_first
>    reflecting the fact that this callback is only used for the
>    first (main) firmware file, and drop the unnecessary
>    prototype.
> 
> Fixes: 5ff013914c62 ("brcmfmac: firmware: Allow per-board firmware binaries")
> Cc: Dmitry Osipenko <digetx@gmail.com>
> Cc: Stefan Hansson <newbyte@disroot.org>

One remark below, but you may add...

Reviewed-by: Arend van Spriel <arend.vanspriel@broadcom.com>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---
>   .../broadcom/brcm80211/brcmfmac/firmware.c    | 29 +++++++++++++------
>   1 file changed, 20 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
> index adfdfc654b10..71ca4a517e42 100644
> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
> @@ -431,8 +431,6 @@ struct brcmf_fw {
>   	void (*done)(struct device *dev, int err, struct brcmf_fw_request *req);
>   };
>   
> -static void brcmf_fw_request_done(const struct firmware *fw, void *ctx);
> -
>   #ifdef CONFIG_EFI
>   /* In some cases the EFI-var stored nvram contains "ccode=ALL" or "ccode=XV"
>    * to specify "worldwide" compatible settings, but these 2 ccode-s do not work
> @@ -638,11 +636,26 @@ static int brcmf_fw_request_firmware(const struct firmware **fw,
>   	return request_firmware(fw, cur->path, fwctx->dev);
>   }
>   
> -static void brcmf_fw_request_done(const struct firmware *fw, void *ctx)
> +static void brcmf_fw_request_done_first(const struct firmware *fw, void *ctx)
>   {
>   	struct brcmf_fw *fwctx = ctx;
> +	struct brcmf_fw_item *first = &fwctx->req->items[0];
> +	static bool retry = true;

using a static seems tricky to me when there are multiple supported 
devices in a system (like in mine ;-)). Probably better to add the flag 
in struct brcmf_fw.

Regards,
Arend