wifi: brcmfmac: avoid handling disabled channels for survey dump

An issue was reported in which periodically error messages are
printed in the kernel log:

[   26.303445] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43455-sdio for chip BCM4345/6
[   26.303554] brcmfmac mmc1:0001:1: Direct firmware load for brcm/brcmfmac43455-sdio.raspberrypi,3-model-b-plus.bin failed with error -2
[   26.516752] brcmfmac_wcc: brcmf_wcc_attach: executing
[   26.528264] brcmfmac: brcmf_c_preinit_dcmds: Firmware: BCM4345/6 wl0: Jan  4 2021 19:56:29 version 7.45.229 (617f1f5 CY) FWID 01-2dbd9d2e
[   27.076829] Bluetooth: hci0: BCM: features 0x2f
[   27.078592] Bluetooth: hci0: BCM43455 37.4MHz Raspberry Pi 3+
[   27.078601] Bluetooth: hci0: BCM4345C0 (003.001.025) build 0342
[   30.142104] Adding 102396k swap on /var/swap.  Priority:-2 extents:1 across:102396k SS
[   30.590017] Bluetooth: MGMT ver 1.22
[  104.897615] brcmfmac: cfg80211_set_channel: set chanspec 0x100e fail, reason -52
[  104.897992] brcmfmac: cfg80211_set_channel: set chanspec 0xd022 fail, reason -52
[  105.007672] brcmfmac: cfg80211_set_channel: set chanspec 0xd026 fail, reason -52
[  105.117654] brcmfmac: cfg80211_set_channel: set chanspec 0xd02a fail, reason -52
[  105.227636] brcmfmac: cfg80211_set_channel: set chanspec 0xd02e fail, reason -52
[  106.987552] brcmfmac: cfg80211_set_channel: set chanspec 0xd090 fail, reason -52
[  106.987911] brcmfmac: cfg80211_set_channel: set chanspec 0xd095 fail, reason -52
[  106.988233] brcmfmac: cfg80211_set_channel: set chanspec 0xd099 fail, reason -52
[  106.988565] brcmfmac: cfg80211_set_channel: set chanspec 0xd09d fail, reason -52
[  106.988909] brcmfmac: cfg80211_set_channel: set chanspec 0xd0a1 fail, reason -52

This happens in brcmf_cfg80211_dump_survey() because we try a disabled
channel. When channel is marked as disabled we do not need to fill any
other info so bail out.

Fixes: 6c04deae ("brcmfmac: Add dump_survey cfg80211 ops for HostApd AutoChannelSelection")
Reported-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20230103124117.271988-2-arend.vanspriel@broadcom.com

drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c

@@ -7937,6 +7937,9 @@ cfg80211_set_channel(struct wiphy *wiphy, struct net_device *dev,
 	struct brcmf_cfg80211_info *cfg = wiphy_to_cfg(wiphy);
 	struct brcmf_if *ifp = netdev_priv(cfg_to_ndev(cfg));
 
+	if (chan->flags & IEEE80211_CHAN_DISABLED)
+		return -EINVAL;
+
 	/* set_channel */
 	chspec = channel_to_chanspec(&cfg->d11inf, chan);
 	if (chspec != INVCHANSPEC) {
@@ -7961,7 +7964,6 @@ brcmf_cfg80211_dump_survey(struct wiphy *wiphy, struct net_device *ndev,
 	struct brcmf_if *ifp = netdev_priv(cfg_to_ndev(cfg));
 	struct brcmf_dump_survey survey = {};
 	struct ieee80211_supported_band *band;
-	struct ieee80211_channel *chan;
 	struct cca_msrmnt_query req;
 	u32 noise;
 	int err;
@@ -7987,13 +7989,10 @@ brcmf_cfg80211_dump_survey(struct wiphy *wiphy, struct net_device *ndev,
 	}
 
 	/* Setting current channel to the requested channel */
-	chan = &band->channels[idx];
-	err = cfg80211_set_channel(wiphy, ndev, chan, NL80211_CHAN_HT20);
-	if (err) {
-		info->channel = chan;
-		info->filled = 0;
+	info->filled = 0;
+	info->channel = &band->channels[idx];
+	if (cfg80211_set_channel(wiphy, ndev, info->channel, NL80211_CHAN_HT20))
 		return 0;
-	}
 
 	/* Disable mpc */
 	brcmf_set_mpc(ifp, 0);
@@ -8028,7 +8027,6 @@ brcmf_cfg80211_dump_survey(struct wiphy *wiphy, struct net_device *ndev,
 	if (err)
 		goto exit;
 
-	info->channel = chan;
 	info->noise = noise;
 	info->time = ACS_MSRMNT_DELAY;
 	info->time_busy = ACS_MSRMNT_DELAY - survey.idle;
@@ -8040,7 +8038,7 @@ brcmf_cfg80211_dump_survey(struct wiphy *wiphy, struct net_device *ndev,
 		SURVEY_INFO_TIME_TX;
 
 	brcmf_dbg(INFO, "OBSS dump: channel %d: survey duration %d\n",
-		  ieee80211_frequency_to_channel(chan->center_freq),
+		  ieee80211_frequency_to_channel(info->channel->center_freq),
 		  ACS_MSRMNT_DELAY);
 	brcmf_dbg(INFO, "noise(%d) busy(%llu) rx(%llu) tx(%llu)\n",
 		  info->noise, info->time_busy, info->time_rx, info->time_tx);