b43: Allow running without PCM firmware

This patch adds code to allow running the device without PCM firmware loaded.
Without PCM firmware we don't have hardware accelerated crypto on
devices with a core rev <= 10.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/b43/b43.h

@@ -774,6 +774,10 @@ struct b43_firmware {
 
 	/* Set to true, if we are using an opensource firmware. */
 	bool opensource;
+	/* Set to true, if the core needs a PCM firmware, but
+	 * we failed to load one. This is always false for
+	 * core rev > 10, as these don't need PCM firmware. */
+	bool pcm_request_failed;
 };
 
 /* Device (802.11 core) initialization status. */

drivers/net/wireless/b43/main.c

@@ -1908,7 +1908,8 @@ static void b43_print_fw_helptext(struct b43_wl *wl, bool error)
 
 static int do_request_fw(struct b43_wldev *dev,
 			 const char *name,
-			 struct b43_firmware_file *fw)
+			 struct b43_firmware_file *fw,
+			 bool silent)
 {
 	char path[sizeof(modparam_fwpostfix) + 32];
 	const struct firmware *blob;
@@ -1932,9 +1933,15 @@ static int do_request_fw(struct b43_wldev *dev,
 		 "b43%s/%s.fw",
 		 modparam_fwpostfix, name);
 	err = request_firmware(&blob, path, dev->dev->dev);
-	if (err) {
-		b43err(dev->wl, "Firmware file \"%s\" not found "
-		       "or load failed.\n", path);
+	if (err == -ENOENT) {
+		if (!silent) {
+			b43err(dev->wl, "Firmware file \"%s\" not found\n",
+			       path);
+		}
+		return err;
+	} else if (err) {
+		b43err(dev->wl, "Firmware file \"%s\" request failed (err=%d)\n",
+		       path, err);
 		return err;
 	}
 	if (blob->size < sizeof(struct b43_fw_header))
@@ -1985,7 +1992,7 @@ static int b43_request_firmware(struct b43_wldev *dev)
 		filename = "ucode13";
 	else
 		goto err_no_ucode;
-	err = do_request_fw(dev, filename, &fw->ucode);
+	err = do_request_fw(dev, filename, &fw->ucode, 0);
 	if (err)
 		goto err_load;
 
@@ -1996,8 +2003,13 @@ static int b43_request_firmware(struct b43_wldev *dev)
 		filename = NULL;
 	else
 		goto err_no_pcm;
-	err = do_request_fw(dev, filename, &fw->pcm);
-	if (err)
+	fw->pcm_request_failed = 0;
+	err = do_request_fw(dev, filename, &fw->pcm, 1);
+	if (err == -ENOENT) {
+		/* We did not find a PCM file? Not fatal, but
+		 * core rev <= 10 must do without hwcrypto then. */
+		fw->pcm_request_failed = 1;
+	} else if (err)
 		goto err_load;
 
 	/* Get initvals */
@@ -2028,7 +2040,7 @@ static int b43_request_firmware(struct b43_wldev *dev)
 	default:
 		goto err_no_initvals;
 	}
-	err = do_request_fw(dev, filename, &fw->initvals);
+	err = do_request_fw(dev, filename, &fw->initvals, 0);
 	if (err)
 		goto err_load;
 
@@ -2062,7 +2074,7 @@ static int b43_request_firmware(struct b43_wldev *dev)
 	default:
 		goto err_no_initvals;
 	}
-	err = do_request_fw(dev, filename, &fw->initvals_band);
+	err = do_request_fw(dev, filename, &fw->initvals_band, 0);
 	if (err)
 		goto err_load;
 
@@ -2186,14 +2198,20 @@ static int b43_upload_microcode(struct b43_wldev *dev)
 	if (dev->fw.opensource) {
 		/* Patchlevel info is encoded in the "time" field. */
 		dev->fw.patch = fwtime;
-		b43info(dev->wl, "Loading OpenSource firmware version %u.%u\n",
-			dev->fw.rev, dev->fw.patch);
+		b43info(dev->wl, "Loading OpenSource firmware version %u.%u%s\n",
+			dev->fw.rev, dev->fw.patch,
+			dev->fw.pcm_request_failed ? " (Hardware crypto not supported)" : "");
 	} else {
 		b43info(dev->wl, "Loading firmware version %u.%u "
 			"(20%.2i-%.2i-%.2i %.2i:%.2i:%.2i)\n",
 			fwrev, fwpatch,
 			(fwdate >> 12) & 0xF, (fwdate >> 8) & 0xF, fwdate & 0xFF,
 			(fwtime >> 11) & 0x1F, (fwtime >> 5) & 0x3F, fwtime & 0x1F);
+		if (dev->fw.pcm_request_failed) {
+			b43warn(dev->wl, "No \"pcm5.fw\" firmware file found. "
+				"Hardware accelerated cryptography is disabled.\n");
+			b43_print_fw_helptext(dev->wl, 0);
+		}
 	}
 
 	if (b43_is_old_txhdr_format(dev)) {
@@ -3358,6 +3376,13 @@ static int b43_op_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
 	if (!dev || b43_status(dev) < B43_STAT_INITIALIZED)
 		goto out_unlock;
 
+	if (dev->fw.pcm_request_failed) {
+		/* We don't have firmware for the crypto engine.
+		 * Must use software-crypto. */
+		err = -EOPNOTSUPP;
+		goto out_unlock;
+	}
+
 	err = -EINVAL;
 	switch (key->alg) {
 	case ALG_WEP: