wifi: brcmfmac: firmware: Handle per-board clm_blob files

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.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Hector Martin <marcan@marcan.st>
Reviewed-by: Alvin Šipraga <alsi@bang-olufsen.dk>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/E1oZDnT-0077a4-4k@rmk-PC.armlinux.org.uk

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
index 15e99d8..6c7c0c8 100644 (file)
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
@@ -587,22 +587,29 @@ 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];
+       char base[BRCMF_FW_NAME_LEN];
+       const char *suffix;
+       char *ret;
 
-       strscpy(alt_path, path, BRCMF_FW_NAME_LEN);
-       /* At least one character + suffix */
-       if (strlen(alt_path) < 5)
+       if (!board_type)
                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;
-       strlcat(alt_path, ".", BRCMF_FW_NAME_LEN);
-       strlcat(alt_path, board_type, BRCMF_FW_NAME_LEN);
-       strlcat(alt_path, suffix, BRCMF_FW_NAME_LEN);
+       suffix = strrchr(path, '.');
+       if (!suffix || suffix == path)
+               return NULL;
+
+       /* strip extension at the end */
+       strscpy(base, path, BRCMF_FW_NAME_LEN);
+       base[suffix - path] = 0;
+
+       ret = kasprintf(GFP_KERNEL, "%s.%s%s", base, board_type, suffix);
+       if (!ret)
+               brcmf_err("out of memory allocating firmware path for '%s'\n",
+                         path);
+
+       brcmf_dbg(TRACE, "FW alt path: %s\n", ret);
 
-       return kstrdup(alt_path, GFP_KERNEL);
+       return ret;
 }
 
 static int brcmf_fw_request_firmware(const struct firmware **fw,
@@ -612,7 +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);