Return-path: Received: from mail-wm0-f67.google.com ([74.125.82.67]:36157 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752107AbeB0MZ7 (ORCPT ); Tue, 27 Feb 2018 07:25:59 -0500 Received: by mail-wm0-f67.google.com with SMTP id 188so22821167wme.1 for ; Tue, 27 Feb 2018 04:25:59 -0800 (PST) Subject: Re: [PATCH] mt7601u: Fix system freeze after resuming from hibernation To: Jakub Kicinski , "Luis R. Rodriguez" Cc: linux-wireless@vger.kernel.org References: <20180214164549.72ee26c3@cakuba.netronome.com> <20180215134738.722654a9@cakuba.netronome.com> <7cebda93-4b7a-e8b3-271f-0144c5e94248@gmail.com> <20180218215520.65c1e9fd@cakuba.netronome.com> <6783d9b9-3523-761f-a8b4-b87732006b3c@gmail.com> <20180225175425.GL14069@wotan.suse.de> <20180226182859.03184215@cakuba.netronome.com> From: cantabile Message-ID: <3382fa4d-c652-68eb-13c3-12dc84ba0dd5@gmail.com> (sfid-20180227_132746_913178_81346EB6) Date: Tue, 27 Feb 2018 14:25:55 +0200 MIME-Version: 1.0 In-Reply-To: <20180226182859.03184215@cakuba.netronome.com> Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 27/02/18 04:28, Jakub Kicinski wrote: > On Sun, 25 Feb 2018 17:54:25 +0000, Luis R. Rodriguez wrote: >> I want to understand the case where the firmware is *not* available on resume? >> Why did that happen? I seem to have read that on a fresh reboot the firmware >> was not needed, and so on probe request_firmware() was not called? Why would >> firmware not be required on a reboot? > > Yes, that is a good question.. John, do you have a theory? My initial > thought was that the UEFI/BIOS loads it during pre-boot, but this is a > USB card, so it's a bit unlikely that UEFI will have a driver for it... > Does this happen when rebooting maybe? > Yes, it happens when rebooting: 1) Plug in the dongle. Message about firmware appears in dmesg: mt7601u 2-3:1.0: ASIC revision: 76010001 MAC revision: 76010500 mt7601u 2-3:1.0: Firmware Version: 0.1.00 Build: 7640 Build time: 201302052146____ mt7601u 2-3:1.0: Warning: unsupported EEPROM version 0d 2) `systemctl reboot`. Message about firmware does not appear in dmesg: mt7601u 2-3:1.0: ASIC revision: 76010001 MAC revision: 76010500 mt7601u 2-3:1.0: Warning: unsupported EEPROM version 0d The dongle is nevertheless perfectly functional after rebooting. I have no idea why it works like this. This is an older laptop, no UEFI.