From 8f1ba8b0ee2679f0b3d22d2a5c1bc70c436fd872 Mon Sep 17 00:00:00 2001 From: Benjamin Li Date: Wed, 27 Oct 2021 10:03:05 -0700 Subject: wcn36xx: ensure pairing of init_scan/finish_scan and start_scan/end_scan An SMD capture from the downstream prima driver on WCN3680B shows the following command sequence for connected scans: - init_scan_req - start_scan_req, channel 1 - end_scan_req, channel 1 - start_scan_req, channel 2 - ... - end_scan_req, channel 3 - finish_scan_req - init_scan_req - start_scan_req, channel 4 - ... - end_scan_req, channel 6 - finish_scan_req - ... - end_scan_req, channel 165 - finish_scan_req Upstream currently never calls wcn36xx_smd_end_scan, and in some cases[1] still sends finish_scan_req twice in a row or before init_scan_req. A typical connected scan looks like this: - init_scan_req - start_scan_req, channel 1 - finish_scan_req - init_scan_req - start_scan_req, channel 2 - ... - start_scan_req, channel 165 - finish_scan_req - finish_scan_req This patch cleans up scanning so that init/finish and start/end are always paired together and correctly nested. - init_scan_req - start_scan_req, channel 1 - end_scan_req, channel 1 - finish_scan_req - init_scan_req - start_scan_req, channel 2 - end_scan_req, channel 2 - ... - start_scan_req, channel 165 - end_scan_req, channel 165 - finish_scan_req Note that upstream will not do batching of 3 active-probe scans before returning to the operating channel, and this patch does not change that. To match downstream in this aspect, adjust IEEE80211_PROBE_DELAY and/or the 125ms max off-channel time in ieee80211_scan_state_decision. [1]: commit d195d7aac09b ("wcn36xx: Ensure finish scan is not requested before start scan") addressed one case of finish_scan_req being sent without a preceding init_scan_req (the case of the operating channel coinciding with the first scan channel); two other cases are: 1) if SW scan is started and aborted immediately, without scanning any channels, we send a finish_scan_req without ever sending init_scan_req, and 2) as SW scan logic always returns us to the operating channel before calling wcn36xx_sw_scan_complete, finish_scan_req is always sent twice at the end of a SW scan Fixes: 8e84c2582169 ("wcn36xx: mac80211 driver for Qualcomm WCN3660/WCN3680 hardware") Signed-off-by: Benjamin Li Tested-by: Bryan O'Donoghue Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20211027170306.555535-4-benl@squareup.com --- drivers/net/wireless/ath/wcn36xx/smd.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'drivers/net/wireless/ath/wcn36xx/smd.c') diff --git a/drivers/net/wireless/ath/wcn36xx/smd.c b/drivers/net/wireless/ath/wcn36xx/smd.c index ed45e2cf039b..e44506e4f1d5 100644 --- a/drivers/net/wireless/ath/wcn36xx/smd.c +++ b/drivers/net/wireless/ath/wcn36xx/smd.c @@ -722,6 +722,7 @@ int wcn36xx_smd_init_scan(struct wcn36xx *wcn, enum wcn36xx_hal_sys_mode mode, wcn36xx_err("hal_init_scan response failed err=%d\n", ret); goto out; } + wcn->sw_scan_init = true; out: mutex_unlock(&wcn->hal_mutex); return ret; @@ -752,6 +753,7 @@ int wcn36xx_smd_start_scan(struct wcn36xx *wcn, u8 scan_channel) wcn36xx_err("hal_start_scan response failed err=%d\n", ret); goto out; } + wcn->sw_scan_channel = scan_channel; out: mutex_unlock(&wcn->hal_mutex); return ret; @@ -782,6 +784,7 @@ int wcn36xx_smd_end_scan(struct wcn36xx *wcn, u8 scan_channel) wcn36xx_err("hal_end_scan response failed err=%d\n", ret); goto out; } + wcn->sw_scan_channel = 0; out: mutex_unlock(&wcn->hal_mutex); return ret; @@ -823,6 +826,7 @@ int wcn36xx_smd_finish_scan(struct wcn36xx *wcn, wcn36xx_err("hal_finish_scan response failed err=%d\n", ret); goto out; } + wcn->sw_scan_init = false; out: mutex_unlock(&wcn->hal_mutex); return ret; -- cgit