Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   "Liu, Zhan" <Zhan.Liu@amd.com>
To:     Nathan Chancellor <natechancellor@gmail.com>,
        "Wentland, Harry" <Harry.Wentland@amd.com>,
        "Li, Sun peng (Leo)" <Sunpeng.Li@amd.com>,
        "Deucher, Alexander" <Alexander.Deucher@amd.com>,
        "Koenig, Christian" <Christian.Koenig@amd.com>,
        "Zhou, David(ChunMing)" <David1.Zhou@amd.com>
CC:     "clang-built-linux@googlegroups.com" 
        <clang-built-linux@googlegroups.com>,
        "dri-devel@lists.freedesktop.org" <dri-devel@lists.freedesktop.org>,
        "amd-gfx@lists.freedesktop.org" <amd-gfx@lists.freedesktop.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [PATCH] drm/amd/display: Don't take the address of
 skip_scdc_overwrite in dc_link_detect_helper
Thread-Topic: [PATCH] drm/amd/display: Don't take the address of
 skip_scdc_overwrite in dc_link_detect_helper
Thread-Index: AQHV4w3nrdEjDXoM7k+tBRh46kQ/F6ga2T+A
Date:   Fri, 14 Feb 2020 16:01:01 +0000
Message-ID: <DM5PR1201MB2554F94D7E206B7690C208109E150@DM5PR1201MB2554.namprd12.prod.outlook.com>
References: <20200214062950.14151-1-natechancellor@gmail.com>
In-Reply-To: <20200214062950.14151-1-natechancellor@gmail.com>
Accept-Language: en-US
Content-Language: en-US
received-spf: None (protection.outlook.com: amd.com does not designate
 permitted sender hosts)
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-Network-Message-Id: 6ffdb09a-7ea3-4819-cc1f-08d7b16716e7
X-MS-Exchange-CrossTenant-originalarrivaltime: 14 Feb 2020 16:01:01.9322
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 3dd8961f-e488-4e60-8e11-a82d994e183d
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: cF2EsSxkd+6UbYflf8L0J5ouH4wmgWLWJfKs+OM+11vYp3rBQc/4Ito1P8SS26Rt
X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM5PR1201MB0012
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org


> -----Original Message-----
> From: dri-devel <dri-devel-bounces@lists.freedesktop.org> On Behalf Of
> Nathan Chancellor
> Sent: 2020/February/14, Friday 1:30 AM
> To: Wentland, Harry <Harry.Wentland@amd.com>; Li, Sun peng (Leo)
> <Sunpeng.Li@amd.com>; Deucher, Alexander
> <Alexander.Deucher@amd.com>; Koenig, Christian
> <Christian.Koenig@amd.com>; Zhou, David(ChunMing)
> <David1.Zhou@amd.com>
> Cc: clang-built-linux@googlegroups.com; Nathan Chancellor
> <natechancellor@gmail.com>; dri-devel@lists.freedesktop.org; amd-
> gfx@lists.freedesktop.org; linux-kernel@vger.kernel.org
> Subject: [PATCH] drm/amd/display: Don't take the address of
> skip_scdc_overwrite in dc_link_detect_helper
>=20
> Clang warns:
>=20
> ../drivers/gpu/drm/amd/amdgpu/../display/dc/core/dc_link.c:980:36:
> warning: address of 'sink->edid_caps.panel_patch.skip_scdc_overwrite'
> will always evaluate to 'true' [-Wpointer-bool-conversion]
>                 if (&sink->edid_caps.panel_patch.skip_scdc_overwrite)
>                 ~~   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~
> 1 warning generated.
>=20
> This is probably not what was intended so remove the address of operator,
> which matches how skip_scdc_overwrite is handled in the rest of the drive=
r.
>=20
> While we're here, drop an extra newline after this if block.
>=20
> Fixes: a760fc1bff03 ("drm/amd/display: add monitor patch to disable SCDC
> read/write")
> Link:
> https://github.com/ClangBuiltLinux/linux/issues/879
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

Thank you!
Reviewed-by: Zhan Liu <zhan.liu@amd.com>

> ---
>=20
> As an aside, I don't see skip_scdc_overwrite assigned a value anywhere, i=
s
> this working as intended?
>=20
>  drivers/gpu/drm/amd/display/dc/core/dc_link.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>=20
> diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
> b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
> index 24d99849be5e..a3bfa05c545e 100644
> --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
> +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
> @@ -977,10 +977,9 @@ static bool dc_link_detect_helper(struct dc_link
> *link,
>  		if ((prev_sink !=3D NULL) && ((edid_status =3D=3D EDID_THE_SAME)
> || (edid_status =3D=3D EDID_OK)))
>  			same_edid =3D is_same_edid(&prev_sink->dc_edid,
> &sink->dc_edid);
>=20
> -		if (&sink->edid_caps.panel_patch.skip_scdc_overwrite)
> +		if (sink->edid_caps.panel_patch.skip_scdc_overwrite)
>  			link->ctx->dc->debug.hdmi20_disable =3D true;
>=20
> -
>  		if (link->connector_signal =3D=3D SIGNAL_TYPE_DISPLAY_PORT
> &&
>  			sink_caps.transaction_type =3D=3D
> DDC_TRANSACTION_TYPE_I2C_OVER_AUX) {
>  			/*
> --
> 2.25.0
>=20
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://nam11.safelinks.protection.outlook.com/?url=3Dhttps%3A%2F%2Flists=
.
> freedesktop.org%2Fmailman%2Flistinfo%2Fdri-
> devel&amp;data=3D02%7C01%7Czhan.liu%40amd.com%7Cb0b05e8e1c944b85
> 0cc108d7b12508b4%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7
> C637172644928182374&amp;sdata=3DOfX%2BPBPCkFt8Elo12VfVBg6Ecnui7Vh
> hZwQFaKy5eyM%3D&amp;reserved=3D0