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

[Dmitry Osipenko <digetx@gmail.com>]

04.08.2021 02:27, Linus Walleij пишет:
> 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>
> 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;
>  	int ret;
>  
> +	/*Something failed with the first firmware request , such as not

There is a problem with whitespaces here.

> +	 * getting the per-board firmware. Retry this, now using the less
> +	 * specific path for the first firmware item, i.e. without the board
> +	 * suffix.
> +	 */
> +	if (!fw && retry) {
> +		ret = request_firmware_nowait(THIS_MODULE, true, first->path,
> +					      fwctx->dev, GFP_KERNEL, fwctx,
> +					      brcmf_fw_request_done_first);
> +		retry = false;
> +		return;
> +	}
> +
>  	ret = brcmf_fw_complete_request(fw, fwctx);
>  
>  	while (ret == 0 && ++fwctx->curpos < fwctx->req->n_items) {
> @@ -702,17 +715,15 @@ int brcmf_fw_get_firmwares(struct device *dev, struct brcmf_fw_request *req,
>  	if (alt_path) {
>  		ret = request_firmware_nowait(THIS_MODULE, true, alt_path,
>  					      fwctx->dev, GFP_KERNEL, fwctx,
> -					      brcmf_fw_request_done);
> +					      brcmf_fw_request_done_first);
>  		kfree(alt_path);
> -	}
> -	/* Else try canonical path */
> -	if (ret) {
> +	} else {
>  		ret = request_firmware_nowait(THIS_MODULE, true, first->path,
>  					      fwctx->dev, GFP_KERNEL, fwctx,
> -					      brcmf_fw_request_done);
> +					      brcmf_fw_request_done_first);
>  	}
>  	if (ret < 0)
> -		brcmf_fw_request_done(NULL, fwctx);
> +		brcmf_fw_request_done_first(NULL, fwctx);
>  
>  	return 0;
>  }
> 

Works, thanks!