On 1/4/2022 8:26 AM, Hector Martin wrote:
> Teach brcm_alt_fw_paths to correctly split off variable length
> extensions, and enable alt firmware lookups for the CLM blob firmware
> requests.
> 
> Apple platforms have per-board CLM blob files.

Are you sure? I am not involved in development for Apple platforms, but 
in general we build a CLM blob specific for a chip revision. As always 
with the blobs they are created at a certain point in time and that is 
mostly why you need another one for a newer platform. Apple tends to do 
things a bit different so you could be right though. Anyway, despite my 
doubts on this it does not change the need for per-board firmware files.

Reviewed-by: Arend van Spriel <arend.vanspriel@broadcom.com>
> Acked-by: Linus Walleij <linus.walleij@linaro.org>
> Signed-off-by: Hector Martin <marcan@marcan.st>
> ---
>   .../broadcom/brcm80211/brcmfmac/firmware.c       | 16 ++++++++--------
>   1 file changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
> index 0eb13e5df517..0497b721136a 100644
> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
> @@ -595,16 +595,16 @@ static int brcmf_fw_complete_request(const struct firmware *fw,
>   static char *brcm_alt_fw_path(const char *path, const char *board_type)
>   {
>   	char alt_path[BRCMF_FW_NAME_LEN];
> -	char suffix[5];
> +	const char *suffix;
>   
> -	strscpy(alt_path, path, BRCMF_FW_NAME_LEN);
> -	/* At least one character + suffix */
> -	if (strlen(alt_path) < 5)
> +	suffix = strrchr(path, '.');
> +	if (!suffix || suffix == path)
>   		return NULL;
>   
> -	/* strip .txt or .bin at the end */
> -	strscpy(suffix, alt_path + strlen(alt_path) - 4, 5);
> -	alt_path[strlen(alt_path) - 4] = 0;
> +	/* strip extension at the end */
> +	strscpy(alt_path, path, BRCMF_FW_NAME_LEN);
> +	alt_path[suffix - path] = 0;
> +
>   	strlcat(alt_path, ".", BRCMF_FW_NAME_LEN);
>   	strlcat(alt_path, board_type, BRCMF_FW_NAME_LEN);
>   	strlcat(alt_path, suffix, BRCMF_FW_NAME_LEN);
> @@ -619,7 +619,7 @@ static int brcmf_fw_request_firmware(const struct firmware **fw,
>   	int ret;
>   
>   	/* Files can be board-specific, first try a board-specific path */
> -	if (cur->type == BRCMF_FW_TYPE_NVRAM && fwctx->req->board_type) {
> +	if (fwctx->req->board_type) {
>   		char *alt_path;
>   
>   		alt_path = brcm_alt_fw_path(cur->path, fwctx->req->board_type);

So all firmware files are attempted with board-specific path now.