Re: Fwd: [PATCH] Add driver to force WMI Thunderbolt controller power status

From: "Bernat, Yehezkel" <yehezkel.bernat@intel.com>
To: "dvhart@infradead.org" <dvhart@infradead.org>,
	"Mario.Limonciello@dell.com" <Mario.Limonciello@dell.com>
Cc: "mika.westerberg@linux.intel.com"
	<mika.westerberg@linux.intel.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"platform-driver-x86@vger.kernel.org" 
	<platform-driver-x86@vger.kernel.org>,
	"hughsient@gmail.com" <hughsient@gmail.com>
Subject: Re: Fwd: [PATCH] Add driver to force WMI Thunderbolt controller power status
Date: Wed, 6 Sep 2017 22:34:02 +0000	[thread overview]
Message-ID: <1504737247.2677.170.camel@intel.com> (raw)
In-Reply-To: <20170906222730.GB8298@fury>

On Wed, 2017-09-06 at 15:27 -0700, Darren Hart wrote:
> On Wed, Sep 06, 2017 at 09:40:02PM +0000, Mario.Limonciello@dell.com
> wrote:
> > 
> > > 
> > > -----Original Message-----
> > > From: Bernat, Yehezkel [mailto:yehezkel.bernat@intel.com]
> > > Sent: Wednesday, September 6, 2017 3:27 PM
> > > To: dvhart@infradead.org; Limonciello, Mario <Mario_Limonciello@D
> > > ell.com>
> > > Cc: mika.westerberg@linux.intel.com; linux-kernel@vger.kernel.org
> > > ; platform-
> > > driver-x86@vger.kernel.org; hughsient@gmail.com
> > > Subject: Re: Fwd: [PATCH] Add driver to force WMI Thunderbolt
> > > controller power
> > > status
> > > 
> > > On Wed, 2017-09-06 at 13:09 -0700, Darren Hart wrote:
> > > > 
> > > > The other question I had about this was if the typical use case
> > > > involves the OS,
> > > > or if the firmware update (for example) would be performed as
> > > > part of
> > > > the
> > > > general platform firmware update (from the UEFI update
> > > > utility).
> > > First, there is the use-case of add-in card, where it's
> > > impossible to
> > > use UEFI-based update, as much as I understand, as the BIOS isn't
> > > expected to expose an ESRT entry for it.
> > > 
> > > Even for built-in controller, my impression is that most OEMs use
> > > a FW
> > > update application (running on Windows) and are not publishing a
> > > UEFI-
> > > based solution.
> > Yeah I'd agree with that impression.
> > 
> > Even if an OEM does choose to publish a UEFI based solution, it's
> > still
> > useful to present FW information for the TBT controller in fwupd
> > however too.
> > 
> > Similar to how fwupd displays the information for the ME even
> > though
> > the ME is typically updated via UEFI.
> So this raises the question: can we come up with a mechanism as part
> of the tb
> driver that will work on both on-board controllers and add on cards?
> In it's
> current form, this driver will only address on-board controllers.

Both this wmi driver and Thunderbolt driver are relevant for both on-
board controllers and add-in cards.
Maybe I'm missing something. Would you mind to elaborate?

> 
> The TB driver could use the WMI method if it exists, or some other
> method to
> power it up, but present the same sysfs interface to userspace...
> 