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: 0bgQikedzcmfTasyT9WqPRPFiYVY6oXOYVAfkFQNsQlvTSbNY8q5b5U/lrTftNqcbopmTCrQzd
 QRCDXL4IBEMQ==
IronPort-SDR: p5MWCZPZfZPBRdSPqi2opxOgDgbM17DeUJP58FisYkUhX39yR/NJkqmKP3uQaZAUjhGZrPuXWU
 aXYEuuU6DE1g==
From:   "Patel, Utkarsh H" <utkarsh.h.patel@intel.com>
To:     Heikki Krogerus <heikki.krogerus@linux.intel.com>
CC:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>,
        "pmalani@chromium.org" <pmalani@chromium.org>,
        "enric.balletbo@collabora.com" <enric.balletbo@collabora.com>,
        "Mani, Rajmohan" <rajmohan.mani@intel.com>,
        "Shaikh, Azhar" <azhar.shaikh@intel.com>
Subject: RE: [PATCH 1/8] usb: typec: Correct the bit values for the
 Thunderbolt rounded/non-rounded cable support
Thread-Topic: [PATCH 1/8] usb: typec: Correct the bit values for the
 Thunderbolt rounded/non-rounded cable support
Thread-Index: AQHWtvniBOcWMcAgx0mTjUqPTtn+0qnBSTgAgABcebA=
Date:   Wed, 11 Nov 2020 01:38:28 +0000
Message-ID: <MWHPR11MB0048B219E9BB7A304891F5EBA9E80@MWHPR11MB0048.namprd11.prod.outlook.com>
References: <20201110003716.5164-1-utkarsh.h.patel@intel.com>
 <20201110003716.5164-2-utkarsh.h.patel@intel.com>
 <20201110121824.GK1224435@kuha.fi.intel.com>
In-Reply-To: <20201110121824.GK1224435@kuha.fi.intel.com>
Accept-Language: en-US
Content-Language: en-US
dlp-reaction: no-action
dlp-version: 11.5.1.3
dlp-product: dlpe-windows
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-Network-Message-Id: 015a75e6-06bc-4490-bc9c-08d885e27d4e
X-MS-Exchange-CrossTenant-originalarrivaltime: 11 Nov 2020 01:38:28.3051
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 46c98d88-e344-4ed4-8496-4ed7712e255d
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: WZfxodplNXn0tpTcoU6MeHpRvNEjkL04mUlEZQ1lf0fUKtsdr9/yFCWHeb4m4+XQ1MBtublE4GtMeWsSXK0I9SJpPLCp4/zxJxDXeIxntuc=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW3PR11MB4538
X-OriginatorOrg: intel.com
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Hi Heikki,

Thank you for the review.

> -----Original Message-----
> From: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> Sent: Tuesday, November 10, 2020 4:18 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 1/8] usb: typec: Correct the bit values for the Thund=
erbolt
> rounded/non-rounded cable support
>=20
> On Mon, Nov 09, 2020 at 04:37:09PM -0800, Utkarsh Patel wrote:
> > Rounded and non-rounded Thunderbolt cables are represented by two bits
> > as per USB Type-C Connector specification v2.0 section F.2.6.
> > Corrected that in the Thunderbolt 3 cable discover mode VDO.
> >
> > Fixes: ca469c292edc ("usb: typec: Add definitions for Thunderbolt 3
> > Alternate Mode")
>=20
> Hold on... Why is this tagged as a fix? What is it fixing?

Ack. I will remove the fix tag in v2.=20

>=20
> Why do we even need this change? The field may have two bits, but only on=
e
> is used: "10b...11b =3D Reserved".

Today, only one bit is being used but as per the spec cable rounded support=
 needs to be two bits field.=20
There is no functional implication but since I am adding changes for rounde=
d cable support hence trying to follow the spec.=20

>=20
> > Signed-off-by: Utkarsh Patel <utkarsh.h.patel@intel.com>
> > ---
> >  include/linux/usb/typec_tbt.h | 5 +++++
> >  1 file changed, 5 insertions(+)
> >
> > diff --git a/include/linux/usb/typec_tbt.h
> > b/include/linux/usb/typec_tbt.h index 47c2d501ddce..aad648d14bb3
> > 100644
> > --- a/include/linux/usb/typec_tbt.h
> > +++ b/include/linux/usb/typec_tbt.h
> > @@ -40,11 +40,16 @@ struct typec_thunderbolt_data {
> >  #define   TBT_CABLE_USB3_PASSIVE	2
> >  #define   TBT_CABLE_10_AND_20GBPS	3
> >  #define TBT_CABLE_ROUNDED		BIT(19)
> > +#define TBT_CABLE_ROUNDED_SUPPORT(_vdo_) \
> > +					(((_vdo_) & GENMASK(20, 19)) >> 19)
> > +#define   TBT_GEN3_NON_ROUNDED                 0
> > +#define   TBT_GEN3_GEN4_ROUNDED_NON_ROUNDED    1
> >  #define TBT_CABLE_OPTICAL		BIT(21)
> >  #define TBT_CABLE_RETIMER		BIT(22)
> >  #define TBT_CABLE_LINK_TRAINING		BIT(23)
> >
> >  #define TBT_SET_CABLE_SPEED(_s_)	(((_s_) & GENMASK(2, 0)) << 16)
> > +#define TBT_SET_CABLE_ROUNDED(_g_)	(((_g_) & GENMASK(1, 0)) <<
> 19)
> >
> >  /* TBT3 Device Enter Mode VDO bits */
> >  #define TBT_ENTER_MODE_CABLE_SPEED(s)	TBT_SET_CABLE_SPEED(s)
>=20
> thanks,
>=20
> --
> Heikki

Sincerely,
Utkarsh Patel.