Return-path: Received: from mail-ua0-f169.google.com ([209.85.217.169]:40447 "EHLO mail-ua0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933623AbeAJMPw (ORCPT ); Wed, 10 Jan 2018 07:15:52 -0500 Received: by mail-ua0-f169.google.com with SMTP id d37so11374363uae.7 for ; Wed, 10 Jan 2018 04:15:52 -0800 (PST) MIME-Version: 1.0 From: Carlo Caione Date: Wed, 10 Jan 2018 12:15:51 +0000 Message-ID: (sfid-20180110_131556_375099_873DCBC1) Subject: RTL8723bu: poor signal and connection troubles To: Jes Sorensen Cc: kvalo@codeaurora.org, linux-wireless@vger.kernel.org, mylene.josserand@free-electrons.com, Linux Upstreaming Team Content-Type: text/plain; charset="UTF-8" Sender: linux-wireless-owner@vger.kernel.org List-ID: Hi, this is a follow up email to [0] since the problem was never fully investigated / solved and I keep seeing the same problem also on my hardware. Also in my case the hardware is a rtl8723bt transceiver (0x0bda:0xb720), this time shipped on the internal USB bus in a cheap laptop branded Zyrex Sky 232. As already reported by Mylene the problem is that using this transceiver and the latest Linus master you can barely see any WiFi network around and also when a WiFi network is actually seen, the connection is impossible since the signal strength is too low to have a reliable connection. Of course during my tests BT is off and no BT driver is probed at all. Using the downstream driver at [1] everything works correctly. I tried to debug a bit the issue, in particular comparing functions and registers related to the antenna setup (.power_on, .enable_rf, .phy_init_antenna_selection, .phy_iq_calibrate hooks) but everything seems pretty much the same on the two drivers (even though slightly differences do exist). Any idea / suggestion on how to debug this problem? I guess it's worth to start looking at this since several platforms are being affected now. Cheers, [0] https://www.spinics.net/lists/netdev/msg468028.html [1] https://github.com/lwfinger/rtl8723bu -- Carlo Caione | +44.7384.69.16.04 | Endless