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To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     "devel@driverdev.osuosl.org" <devel@driverdev.osuosl.org>,
        linux-wireless@vger.kernel.org, stable@vger.kernel.org
From:   Malcolm Priestley <tvboxspy@gmail.com>
Subject: [PATCH] staging: vt6656: Power save stop wake_up_count wrap around.
Message-ID: <fce47bb5-7ca6-7671-5094-5c6107302f2b@gmail.com>
Date:   Tue, 14 Apr 2020 11:39:23 +0100
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conf.listen_interval can sometimes be zero causing wake_up_count
to wrap around up to many beacons too late causing
CTRL-EVENT-BEACON-LOSS as in.

wpa_supplicant[795]: message repeated 45 times: [..CTRL-EVENT-BEACON-LOSS ]

Fixes: 43c93d9bf5e2 ("staging: vt6656: implement power saving code.")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
---
 drivers/staging/vt6656/usbpipe.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/vt6656/usbpipe.c b/drivers/staging/vt6656/usbpipe.c
index eae211e5860f..91b62c3dff7b 100644
--- a/drivers/staging/vt6656/usbpipe.c
+++ b/drivers/staging/vt6656/usbpipe.c
@@ -207,7 +207,8 @@ static void vnt_int_process_data(struct vnt_private *priv)
 				priv->wake_up_count =
 					priv->hw->conf.listen_interval;
 
-			--priv->wake_up_count;
+			if (priv->wake_up_count)
+				--priv->wake_up_count;
 
 			/* Turn on wake up to listen next beacon */
 			if (priv->wake_up_count == 1)
-- 
2.25.1