From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 487CEC4320A for ; Wed, 11 Aug 2021 13:23:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1C3A060FC0 for ; Wed, 11 Aug 2021 13:23:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231249AbhHKNYM (ORCPT ); Wed, 11 Aug 2021 09:24:12 -0400 Received: from mga17.intel.com ([192.55.52.151]:1792 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230425AbhHKNYA (ORCPT ); Wed, 11 Aug 2021 09:24:00 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10072"; a="195388089" X-IronPort-AV: E=Sophos;i="5.84,313,1620716400"; d="scan'208";a="195388089" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Aug 2021 06:23:29 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.84,313,1620716400"; d="scan'208";a="590091824" Received: from kuha.fi.intel.com ([10.237.72.162]) by fmsmga001.fm.intel.com with SMTP; 11 Aug 2021 06:23:27 -0700 Received: by kuha.fi.intel.com (sSMTP sendmail emulation); Wed, 11 Aug 2021 16:23:26 +0300 Date: Wed, 11 Aug 2021 16:23:26 +0300 From: Heikki Krogerus To: Oliver Neukum Cc: USB list Subject: Re: UCSI failing due to probe() getting version 0 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Thu, Aug 05, 2021 at 04:04:03PM +0200, Oliver Neukum wrote: > Hi, > > I am trying this on a new laptop, but I am getting a result I do not > understand. > ucsi_acpi_probe() is called, but ucsi_register() fails with -ENODEV, > because ucsi->version is 0. > > If I dump the ucsi_acpi buffer I get: > > 00 00 00 00 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > > And, frankly I do not understand that. Why have the ACPI device > but show version number 0? Because of BIOS bugs. Ideally we should be able to rely on the _STA method of the ACPI device, but unfortunately with UCSI we can't rely on that alone. On some systems the BIOS claims that the device is enabled (based on _STA) even when the platform doesn't actually support UCSI at all. If you remove the check, does the driver work? Br, -- heikki