Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
IronPort-SDR: EZH4zQYRuuacaSxhZuTOKx4C+Ge+AnhOaDH3ealxQ+QXhe1uinI8eoxc02px6jQTiNiLgr4vhC
 AaATsRkQNI0Q==
IronPort-SDR: iaEAHSVLG8Cls/cyb2sG38KkiKCv0wiFG07Tx16NAdCCHmXDPm+bUQc5wdTROqoWYWPfLzy7rE
 cU9qR2RPRZog==
Date:   Tue, 29 Sep 2020 19:53:25 +0300
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     "Limonciello, Mario" <Mario.Limonciello@dell.com>
Cc:     Hans de Goede <hdegoede@redhat.com>,
        =?utf-8?Q?Barnab=C3=A1s_P=C5=91cze?= <pobrn@protonmail.com>,
        "platform-driver-x86@vger.kernel.org" 
        <platform-driver-x86@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Takashi Iwai <tiwai@suse.de>
Subject: Re: Keyboard regression by intel-vbtn
Message-ID: <20200929165325.GW3956970@smile.fi.intel.com>
References: <s5hft71klxl.wl-tiwai@suse.de>
 <bedb9d1b-3cca-43e2-ee44-1aac0e09a605@redhat.com>
 <s5h8sctkk2b.wl-tiwai@suse.de>
 <-ICwwoAndae7T9i-Ymr7Nx9jnXVd7H54dnkMmCWUcApM1S0FUPplPWhg8DVXkphN0L4DoTy24robhTiBzMmSBKZRl-P8VEXIX5r6ttceA_8=@protonmail.com>
 <8c3d8a56-541f-aafc-1be9-4d72d374effe@redhat.com>
 <DM6PR19MB2636C7C411E220565F39E741FA320@DM6PR19MB2636.namprd19.prod.outlook.com>
 <55e021b7-5e1b-986b-07ec-279398570e40@redhat.com>
 <DM6PR19MB2636FFC274423BB564A7532CFA320@DM6PR19MB2636.namprd19.prod.outlook.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <DM6PR19MB2636FFC274423BB564A7532CFA320@DM6PR19MB2636.namprd19.prod.outlook.com>
Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo
Precedence: bulk

On Tue, Sep 29, 2020 at 02:25:12PM +0000, Limonciello, Mario wrote:
> > -----Original Message-----
> > From: Hans de Goede <hdegoede@redhat.com>
> > Sent: Tuesday, September 29, 2020 7:54
> > On 9/29/20 2:27 PM, Limonciello, Mario wrote:

...

> > >> I'm afraid that the only answer which I have to these questions
> > >> is not helpful, but in my experience it is true: "firmware sucks".
> > >
> > > So FWIW there is a Dell 2-in-1 that has been conflated into this same issue.
> > > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1822394
> > 
> > That is what a somewhat old kernel (5.0.0) which I guess may
> > lack your fix to check the chassis-type.
> > 
> > Interesting that this actually is a 2-in-1 though.
> > 
> > Also interesting that according to the reporter this was
> > triggered by a BIOS update.
> > 
> > If you by any chance can provide an acpidump with both the
> > 1.2.0 and 1.4.0 BIOS versions that would be very interesting.
> 
> I requested on the Ubuntu bug for someone to provide these.
> 
> > > Something that is confusing to me is that on the Windows side all these
> > > machines use the same Intel driver for this infrastructure no matter the
> > > OEM.
> > > So they can't possibly be putting in quirk specific stuff in the driver side
> > > can they?
> > >
> > > It has to make you wonder if some baseline assumptions made in the
> > > driver early on around tablet mode support are completely false.
> > 
> > I'm not saying your wrong. If you can get Intel to provide
> > us with some documentation, or Windows driver source code
> > for this, then that would be great.
> > 
> > AFAICT the Linux driver currently is entirely based on
> > reverse engineering.
> 
> That's correct it was originally reverse engineered.
> 
> Andy,
> 
> As there is no publicly available documentation, could you see if it would it be
> possible to get someone internal to Intel to compare private documentation to the
> driver to see if something basic is missing or done wrong?

I'm afraid that's all was designed solely for Windows and all information is
not available to us in any form (basically somebody has to ask for WOS driver
sources, and funny that as a customer your has more power to get this than mere
in-house Linux engineer as me).

-- 
With Best Regards,
Andy Shevchenko