Unverified Commit 6de79dd3 authored Apr 07, 2022 by H. Nikolaus Schaller Committed by Paul Cercueil Apr 11, 2022

drm/bridge: display-connector: add ddc-en gpio support



"hdmi-connector.yaml" bindings defines an optional property
"ddc-en-gpios" for a single gpio to enable DDC operation.

Usually this controls +5V power on the HDMI connector.
This +5V may also be needed for HPD.

This was not reflected in code but is needed to make the CI20
board work.

Now, the driver activates the ddc gpio after probe and
deactivates after remove so it is "almost on".

But only if this driver is loaded (and not e.g. blacklisted
as module).

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Link: https://patchwork.freedesktop.org/patch/msgid/3607e924b7c0cf0be956c0d49894be1442dbda41.1649330171.git.hns@goldelico.com

parent d72dcbe9

drivers/gpu/drm/bridge/display-connector.c

+15 −0

Original line number	Diff line number	Diff line
		@@ -24,6 +24,7 @@ struct display_connector {
		int hpd_irq;

		struct regulator *dp_pwr;
		struct gpio_desc *ddc_en;
		};

		static inline struct display_connector *
		@@ -345,6 +346,17 @@ static int display_connector_probe(struct platform_device *pdev)
		}
		}

		/* enable DDC */
		if (type == DRM_MODE_CONNECTOR_HDMIA) {
		conn->ddc_en = devm_gpiod_get_optional(&pdev->dev, "ddc-en",
		GPIOD_OUT_HIGH);

		if (IS_ERR(conn->ddc_en)) {
		dev_err(&pdev->dev, "Couldn't get ddc-en gpio\n");
		return PTR_ERR(conn->ddc_en);
		}
		}

		conn->bridge.funcs = &display_connector_bridge_funcs;
		conn->bridge.of_node = pdev->dev.of_node;

		@@ -373,6 +385,9 @@ static int display_connector_remove(struct platform_device *pdev)
		{
		struct display_connector *conn = platform_get_drvdata(pdev);

		if (conn->ddc_en)
		gpiod_set_value(conn->ddc_en, 0);

		if (conn->dp_pwr)
		regulator_disable(conn->dp_pwr);