On Mon, Dec 30, 2024 at 07:04:51AM +0000, Ying Liu wrote:
> On 12/26/2024, Marek Vasut wrote:
> > On 12/24/24 5:21 AM, Dmitry Baryshkov wrote:
> > > On Tue, Dec 24, 2024 at 02:46:14AM +0100, Marek Vasut wrote:
> > >> The dw-hdmi output_port is set to 1 in order to look for a connector
> > >> next bridge in order to get DRM_BRIDGE_ATTACH_NO_CONNECTOR
> > working.
> > >> The output_port set to 1 makes the DW HDMI driver core look up the
> > >> next bridge in DT, where the next bridge is often the hdmi-connector .
> > >>
> > >> Similar to 0af5e0b41110 ("drm/meson: encoder_hdmi: switch to bridge
> > DRM_BRIDGE_ATTACH_NO_CONNECTOR")
> > >>
> > >> Signed-off-by: Marek Vasut <marex@xxxxxxx>
> > >> ---
> > >> Cc: Andrzej Hajda <andrzej.hajda@xxxxxxxxx>
> > >> Cc: David Airlie <airlied@xxxxxxxxx>
> > >> Cc: Fabio Estevam <festevam@xxxxxxxxx>
> > >> Cc: Jernej Skrabec <jernej.skrabec@xxxxxxxxx>
> > >> Cc: Jonas Karlman <jonas@xxxxxxxxx>
> > >> Cc: Laurent Pinchart <Laurent.pinchart@xxxxxxxxxxxxxxxx>
> > >> Cc: Liu Ying <victor.liu@xxxxxxx>
> > >> Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
> > >> Cc: Maxime Ripard <mripard@xxxxxxxxxx>
> > >> Cc: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
> > >> Cc: Pengutronix Kernel Team <kernel@xxxxxxxxxxxxxx>
> > >> Cc: Robert Foss <rfoss@xxxxxxxxxx>
> > >> Cc: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
> > >> Cc: Shawn Guo <shawnguo@xxxxxxxxxx>
> > >> Cc: Simona Vetter <simona@xxxxxxxx>
> > >> Cc: Stefan Agner <stefan@xxxxxxxx>
> > >> Cc: Thomas Zimmermann <tzimmermann@xxxxxxx>
> > >> Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
> > >> Cc: imx@xxxxxxxxxxxxxxx
> > >> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> > >> ---
> > >> V2: No change
> > >> ---
> > >> drivers/gpu/drm/bridge/imx/Kconfig | 1 +
> > >> drivers/gpu/drm/bridge/imx/imx8mp-hdmi-tx.c | 1 +
> > >> 2 files changed, 2 insertions(+)
> > >>
> > >> diff --git a/drivers/gpu/drm/bridge/imx/Kconfig
> > b/drivers/gpu/drm/bridge/imx/Kconfig
> > >> index 9a480c6abb856..d8e9fbf75edbb 100644
> > >> --- a/drivers/gpu/drm/bridge/imx/Kconfig
> > >> +++ b/drivers/gpu/drm/bridge/imx/Kconfig
> > >> @@ -27,6 +27,7 @@ config DRM_IMX8MP_DW_HDMI_BRIDGE
> > >> config DRM_IMX8MP_HDMI_PVI
> > >> tristate "Freescale i.MX8MP HDMI PVI bridge support"
> > >> depends on OF
> > >> + select DRM_DISPLAY_CONNECTOR
> > >> help
> > >> Choose this to enable support for the internal HDMI TX Parallel
> > >> Video Interface found on the Freescale i.MX8MP SoC.
> > >> diff --git a/drivers/gpu/drm/bridge/imx/imx8mp-hdmi-tx.c
> > b/drivers/gpu/drm/bridge/imx/imx8mp-hdmi-tx.c
> > >> index 1e7a789ec2890..4ebae5ad072ad 100644
> > >> --- a/drivers/gpu/drm/bridge/imx/imx8mp-hdmi-tx.c
> > >> +++ b/drivers/gpu/drm/bridge/imx/imx8mp-hdmi-tx.c
> > >> @@ -101,6 +101,7 @@ static int imx8mp_dw_hdmi_probe(struct
> > platform_device *pdev)
> > >> plat_data->phy_name = "SAMSUNG HDMI TX PHY";
> > >> plat_data->priv_data = hdmi;
> > >> plat_data->phy_force_vendor = true;
> > >> + plat_data->output_port = 1;
> > >
> > > Quoting my feedback to a similar Liu's patch:
> > >
> > > This will break compatibility with older DT files, which don't have
> > > output port. I think you need to add output_port_optional flag to
> > > dw_hdmi_plat_data and still return 0 from dw_hdmi_parse_dt() if the flag
> > > is set, but there is no remote node.
> > Looking at the upstream imx8mp*dts , the oldest commit which adds HDMI
> > support is commit:
> >
> > 3e67a1ddd56d ("arm64: dts: imx8mp: Enable HDMI on
> > TQMa8MPxL/MBa8MPxL")
> >
> > That already contains the HDMI connector node. Every follow up addition
> > of HDMI to another device has been a copy of the same commit, with
> > connector, so I think it is safe to say, no upstream DT is going to be
> > broken by this change. Do we care about hypothetical downstream DTs
> > which may be missing the connector ?
>
> These have no HDMI connector nodes:
> arch/arm64/boot/dts/freescale/imx8mp-aristainetos3a-som-v1.dtsi
> arch/arm64/boot/dts/freescale/imx8mp-kontron-bl-osm-s.dts
> arch/arm64/boot/dts/freescale/imx8mp-kontron-smarc-eval-carrier.dts
> arch/arm64/boot/dts/freescale/imx8mp-msc-sm2s-ep1.dts
Indeed. I should be less trustful.
Unreviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
--
With best wishes
Dmitry
