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References: <20230120173226.98569-1-hamza.mahfooz@amd.com>
In-Reply-To: <20230120173226.98569-1-hamza.mahfooz@amd.com>
From:   Alex Deucher <alexdeucher@gmail.com>
Date:   Fri, 20 Jan 2023 12:32:40 -0500
Message-ID: <CADnq5_MVRBeduHKqUAcPSRF9ruAU5WVOG0w407edocCKME8nXQ@mail.gmail.com>
Subject: Re: [PATCH] drm/amd/display: use a more appropriate return value in dp_retrieve_lttpr_cap()
To:     Hamza Mahfooz <hamza.mahfooz@amd.com>
Cc:     amd-gfx@lists.freedesktop.org, Arnd Bergmann <arnd@arndb.de>,
        Leo Li <sunpeng.li@amd.com>, Wenjing Liu <wenjing.liu@amd.com>,
        "Pan, Xinhui" <Xinhui.Pan@amd.com>,
        Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>,
        linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
        Daniel Vetter <daniel@ffwll.ch>,
        Alex Deucher <alexander.deucher@amd.com>,
        David Airlie <airlied@gmail.com>,
        Harry Wentland <harry.wentland@amd.com>,
        =?UTF-8?Q?Christian_K=C3=B6nig?= <christian.koenig@amd.com>
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Acked-by: Alex Deucher <alexander.deucher@amd.com>

On Fri, Jan 20, 2023 at 12:31 PM Hamza Mahfooz <hamza.mahfooz@amd.com> wrote:
>
> Not all ASICs support LTTPR, however if they don't it doesn't mean that
> we have encountered unexpected behaviour. So, use DC_NOT_SUPPORTED
> instead of DC_ERROR_UNEXPECTED.
>
> Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
> Signed-off-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
> ---
>  drivers/gpu/drm/amd/display/dc/link/link_dp_capability.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/display/dc/link/link_dp_capability.c b/drivers/gpu/drm/amd/display/dc/link/link_dp_capability.c
> index e72ad1b8330f..21fd9275ae4c 100644
> --- a/drivers/gpu/drm/amd/display/dc/link/link_dp_capability.c
> +++ b/drivers/gpu/drm/amd/display/dc/link/link_dp_capability.c
> @@ -1462,7 +1462,7 @@ enum dc_status dp_retrieve_lttpr_cap(struct dc_link *link)
>         bool vbios_lttpr_interop = link->dc->caps.vbios_lttpr_aware;
>
>         if (!vbios_lttpr_interop || !link->dc->caps.extended_aux_timeout_support)
> -               return DC_ERROR_UNEXPECTED;
> +               return DC_NOT_SUPPORTED;
>
>         /* By reading LTTPR capability, RX assumes that we will enable
>          * LTTPR extended aux timeout if LTTPR is present.
> --
> 2.39.0
>