linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Usyskin, Alexander" <alexander.usyskin@intel.com>
To: Mika Westerberg <mika.westerberg@linux.intel.com>,
	Won Chung <wonchung@google.com>,
	"Winkler, Tomas" <tomas.winkler@intel.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>,
	Benson Leung <bleung@chromium.org>,
	Prashant Malani <pmalani@chromium.org>,
	"Ceraolo Spurio, Daniele" <daniele.ceraolospurio@intel.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [PATCH 0/2] thunderbolt: Link USB4 ports to their USB Type-C connectors
Date: Sun, 24 Apr 2022 05:12:39 +0000	[thread overview]
Message-ID: <MW3PR11MB46517BE51D4DCBC02B463C0EEDF99@MW3PR11MB4651.namprd11.prod.outlook.com> (raw)
In-Reply-To: <YmDy/xEsyktRS6D+@lahna>

> > > > Currently, USB port is linked to Type C connector, using the component
> > > > framework, if they share the same _PLD fields from ACPI table. Type C
> > > > port-mapper searches for devices with the same _PLD values, and
> > > > aggregate them as components.
> > > >
> > > > When there is another device that share the same _PLD but does not
> > > > registers a component, Type C connector (component master) would never
> > > > be bound due to a component match entry device without a component
> > > > registered. There exists some cases where USB4 port also shares the same
> > > > _PLD with USB port and Type C connector, so we need to register a
> > > > component for USB4 ports too, linking USB4 port with Type C connector.
> > > > Otherwise, link between USB port and Type C connector would not
> > > > work either.
> > > >
> > > > Due to the nature of the component framework, all registered components
> > > > are shared by all component match despite the relevance. MEI subsystems
> > > > also use the component framework to bind to i915 driver, which try to
> > > > match components registered by USB ports and USB4 ports. This can be
> > > > problematic since MEI assumes that there is a driver bound to the
> > > > component device, while USB4 port does not bind to any drivers. MEI's
> > > > component match callback functions should handle such case to avoid
> NULL
> > > > pointer dereference when USB4 port registers a component.
> > > >
> > > > In summary this patch series
> > > > 1. Fixes MEI subsystem's component match callbacks to handle a
> component
> > > > device without any driver bound
> > > > 2. Registers a component for USB4 ports to link them to Type C
> > > > connectors, similar to USB ports.
> > > >
> > > > Heikki Krogerus (1):
> > > >   thunderbolt: Link USB4 ports to their USB Type-C connectors
> > > >
> > > > Won Chung (1):
> > > >   misc/mei: Add NULL check to component match callback functions
> > >
> > > The Thunderbolt patch looks good to me. Do you want me to take the both
> > > patches through the Thunderbolt tree or they can go separately? I need
> > > an ack from the mei maintainer it goes through my tree.
> >
> > Hi Mika,
> >
> > I would prefer the two patches to go to the same tree since it can
> > cause a crash with only the second patch (tbt). Would that sound okay?
> 
> Sounds good to me.

Tomas is MEI maintainer and should ack MEI patch

-- 
Thanks,
Sasha



  reply	other threads:[~2022-04-24  5:13 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-04-18 17:59 [PATCH 0/2] thunderbolt: Link USB4 ports to their USB Type-C connectors Won Chung
2022-04-18 17:59 ` [PATCH 1/2] misc/mei: Add NULL check to component match callback functions Won Chung
2022-04-25 16:56   ` Won Chung
2022-04-28 18:11     ` Winkler, Tomas
2022-04-18 17:59 ` [PATCH 2/2] thunderbolt: Link USB4 ports to their USB Type-C connectors Won Chung
2022-04-20 10:52 ` [PATCH 0/2] " Mika Westerberg
2022-04-20 16:39   ` Won Chung
2022-04-21  6:00     ` Mika Westerberg
2022-04-24  5:12       ` Usyskin, Alexander [this message]
2022-04-25 16:51         ` Won Chung
2022-04-28 18:34           ` Won Chung
2022-04-29  9:28             ` Mika Westerberg

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=MW3PR11MB46517BE51D4DCBC02B463C0EEDF99@MW3PR11MB4651.namprd11.prod.outlook.com \
    --to=alexander.usyskin@intel.com \
    --cc=bleung@chromium.org \
    --cc=daniele.ceraolospurio@intel.com \
    --cc=heikki.krogerus@linux.intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mika.westerberg@linux.intel.com \
    --cc=pmalani@chromium.org \
    --cc=tomas.winkler@intel.com \
    --cc=wonchung@google.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).