Re: [PATCH 2/5] phy: core: Define TBT phy_mode

[Dmitry Baryshkov]

On Mon, May 18, 2026 at 02:29:26PM +0200, Konrad Dybcio wrote:
> On 5/18/26 2:25 PM, Dmitry Baryshkov wrote:
> > On Mon, May 18, 2026 at 12:29:49PM +0200, Konrad Dybcio wrote:
> >> From: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxxxx>
> >>
> >> There exist OS-accessible USB4 and Thunderbolt PHYs that need specific
> >> configuration. Define a new phy_mode for them.
> >>
> >> Currently, USB4 and TBT3 are defined as submodes, because they're quite
> >> distinct, most visibly in the electrical/analog aspects (slightly
> >> different frequencies, timings, etc.). This results in a need to make
> >> the PHY aware of the actual mode needed (at least in the Qualcomm
> >> implementation, but I believe that'll be a general need).
> >>
> >> Newer versions of TBT are basically supersets of USB4 with higher
> >> host-side requirements, so these are not defined. This can always be
> >> changed as necessary.
> >>
> >> Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxxxx>
> >> ---
> >>  include/linux/phy/phy-tbt.h | 14 ++++++++++++++
> >>  include/linux/phy/phy.h     |  2 ++
> >>  2 files changed, 16 insertions(+)
> >>
> >> diff --git a/include/linux/phy/phy-tbt.h b/include/linux/phy/phy-tbt.h
> >> new file mode 100644
> >> index 000000000000..5f48059814e1
> >> --- /dev/null
> >> +++ b/include/linux/phy/phy-tbt.h
> >> @@ -0,0 +1,14 @@
> >> +/* SPDX-License-Identifier: GPL-2.0 */
> >> +/*
> >> + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
> >> + */
> >> +
> >> +#ifndef __PHY_TBT_H_
> >> +#define __PHY_TBT_H_
> >> +
> >> +enum tbt_phy_submode {
> >> +	PHY_SUBMODE_TBT3,
> >> +	PHY_SUBMODE_USB4,
> > 
> > Do we need TBT2 as a separate submode?
> 
> I would like to avoid extending that unless there's a user for it

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>


-- 
With best wishes
Dmitry