| Message ID | 20201113202503.6559-6-utkarsh.h.patel@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Thunderbolt3/USB4 cable rounded and active cable plug link training support | expand |
On Fri, Nov 13, 2020 at 12:25:00PM -0800, Utkarsh Patel wrote: > USB4 also uses same cable properties as Thunderbolt 3 so use Thunderbolt 3 > cable discover mode VDO to fill details such as active cable plug link > training and cable rounded support. I'm sorry, but I think that has to be explained better. We only need the Thunderbolt 3 properties when we create the USB4 connection with Thunderbolt 3 cables. With USB4 cables that information is simply not available. Claiming that USB4 uses the same properties in general is not true. > Suggested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > Signed-off-by: Utkarsh Patel <utkarsh.h.patel@intel.com> > -- > Changes in v2: > - No change. > -- > --- > include/linux/usb/typec.h | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/include/linux/usb/typec.h b/include/linux/usb/typec.h > index 6be558045942..d91e09d9d91c 100644 > --- a/include/linux/usb/typec.h > +++ b/include/linux/usb/typec.h > @@ -75,6 +75,7 @@ enum typec_orientation { > /* > * struct enter_usb_data - Enter_USB Message details > * @eudo: Enter_USB Data Object > + * @tbt_cable_vdo: TBT3 Cable Discover Mode Response > * @active_link_training: Active Cable Plug Link Training > * > * @active_link_training is a flag that should be set with uni-directional SBRX Please also explain the same here with a short comment. So basically, if the USB4 connection is created using TBT3 cable, then we need to supply also the TBT3 Cable VDO as part of this data. But if USB4 cable is used, then that member should not be filled at all. > @@ -83,6 +84,7 @@ enum typec_orientation { > */ > struct enter_usb_data { > u32 eudo; > + u32 tbt_cable_vdo; > unsigned char active_link_training:1; > }; thanks,
Hi Utkarsh, On Fri, Nov 13, 2020 at 12:25:00PM -0800, Utkarsh Patel wrote: > USB4 also uses same cable properties as Thunderbolt 3 so use Thunderbolt 3 > cable discover mode VDO to fill details such as active cable plug link > training and cable rounded support. > > Suggested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > Signed-off-by: Utkarsh Patel <utkarsh.h.patel@intel.com> > > -- > Changes in v2: > - No change. > -- > --- > include/linux/usb/typec.h | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/include/linux/usb/typec.h b/include/linux/usb/typec.h > index 6be558045942..d91e09d9d91c 100644 > --- a/include/linux/usb/typec.h > +++ b/include/linux/usb/typec.h > @@ -75,6 +75,7 @@ enum typec_orientation { > /* > * struct enter_usb_data - Enter_USB Message details > * @eudo: Enter_USB Data Object > + * @tbt_cable_vdo: TBT3 Cable Discover Mode Response > * @active_link_training: Active Cable Plug Link Training > * > * @active_link_training is a flag that should be set with uni-directional SBRX > @@ -83,6 +84,7 @@ enum typec_orientation { > */ > struct enter_usb_data { > u32 eudo; > + u32 tbt_cable_vdo; Can we instead just include a field for the rounded cable support property , similar to what was done for active_link_training? That way this gets decoupled from whether a TBT VDO was present in the cable or not > unsigned char active_link_training:1; > }; > > -- > 2.17.1 > Best regards, -Prashant
Hi Heikki, > -----Original Message----- > From: Heikki Krogerus <heikki.krogerus@linux.intel.com> > Sent: Tuesday, November 17, 2020 4:10 AM > To: Patel, Utkarsh H <utkarsh.h.patel@intel.com> > Cc: linux-kernel@vger.kernel.org; linux-usb@vger.kernel.org; > pmalani@chromium.org; enric.balletbo@collabora.com; Mani, Rajmohan > <rajmohan.mani@intel.com>; Shaikh, Azhar <azhar.shaikh@intel.com> > Subject: Re: [PATCH v2 5/8] usb: typec: Use Thunderbolt 3 cable discover > mode VDO in Enter_USB message > > On Fri, Nov 13, 2020 at 12:25:00PM -0800, Utkarsh Patel wrote: > > USB4 also uses same cable properties as Thunderbolt 3 so use > > Thunderbolt 3 cable discover mode VDO to fill details such as active > > cable plug link training and cable rounded support. > > I'm sorry, but I think that has to be explained better. We only need the > Thunderbolt 3 properties when we create the USB4 connection with > Thunderbolt 3 cables. With USB4 cables that information is simply not > available. Claiming that USB4 uses the same properties in general is not true. Ack. I will change the commit message. > > > Suggested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > > Signed-off-by: Utkarsh Patel <utkarsh.h.patel@intel.com> > > -- > > Changes in v2: > > - No change. > > -- > > --- > > include/linux/usb/typec.h | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/include/linux/usb/typec.h b/include/linux/usb/typec.h > > index 6be558045942..d91e09d9d91c 100644 > > --- a/include/linux/usb/typec.h > > +++ b/include/linux/usb/typec.h > > @@ -75,6 +75,7 @@ enum typec_orientation { > > /* > > * struct enter_usb_data - Enter_USB Message details > > * @eudo: Enter_USB Data Object > > + * @tbt_cable_vdo: TBT3 Cable Discover Mode Response > > * @active_link_training: Active Cable Plug Link Training > > * > > * @active_link_training is a flag that should be set with > > uni-directional SBRX > > Please also explain the same here with a short comment. So basically, if the > USB4 connection is created using TBT3 cable, then we need to supply also the > TBT3 Cable VDO as part of this data. But if USB4 cable is used, then that > member should not be filled at all. Ack. > > > @@ -83,6 +84,7 @@ enum typec_orientation { > > */ > > struct enter_usb_data { > > u32 eudo; > > + u32 tbt_cable_vdo; > > unsigned char active_link_training:1; > > }; > > thanks, > > -- > Heikki Sincerely, Utkarsh Patel.
On Tue, Nov 17, 2020 at 1:16 PM Prashant Malani <pmalani@chromium.org> wrote: > > Hi Utkarsh, > > On Fri, Nov 13, 2020 at 12:25:00PM -0800, Utkarsh Patel wrote: > > USB4 also uses same cable properties as Thunderbolt 3 so use Thunderbolt 3 > > cable discover mode VDO to fill details such as active cable plug link > > training and cable rounded support. On digging into the Cros EC code further, sounds like active cable link training and cable rounded are necessarily only part of cables that have a TBT cable VDO, so sounds like the approach in the patch is fine. Sorry for the noise. Best regards, -Prashant
diff --git a/include/linux/usb/typec.h b/include/linux/usb/typec.h index 6be558045942..d91e09d9d91c 100644 --- a/include/linux/usb/typec.h +++ b/include/linux/usb/typec.h @@ -75,6 +75,7 @@ enum typec_orientation { /* * struct enter_usb_data - Enter_USB Message details * @eudo: Enter_USB Data Object + * @tbt_cable_vdo: TBT3 Cable Discover Mode Response * @active_link_training: Active Cable Plug Link Training * * @active_link_training is a flag that should be set with uni-directional SBRX @@ -83,6 +84,7 @@ enum typec_orientation { */ struct enter_usb_data { u32 eudo; + u32 tbt_cable_vdo; unsigned char active_link_training:1; };
USB4 also uses same cable properties as Thunderbolt 3 so use Thunderbolt 3 cable discover mode VDO to fill details such as active cable plug link training and cable rounded support. Suggested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Utkarsh Patel <utkarsh.h.patel@intel.com> -- Changes in v2: - No change. -- --- include/linux/usb/typec.h | 2 ++ 1 file changed, 2 insertions(+)