Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 42 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/media/cec-gpio.txt b/Documentation/devicetree/bindings/media/cec-gpio.txt
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index 000000000..47e8d73d3
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+++ b/Documentation/devicetree/bindings/media/cec-gpio.txt
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+* HDMI CEC GPIO driver
+
+The HDMI CEC GPIO module supports CEC implementations where the CEC line
+is hooked up to a pull-up GPIO line and - optionally - the HPD line is
+hooked up to another GPIO line.
+
+Please note: the maximum voltage for the CEC line is 3.63V, for the HPD and
+5V lines it is 5.3V. So you may need some sort of level conversion circuitry
+when connecting them to a GPIO line.
+
+Required properties:
+  - compatible: value must be "cec-gpio".
+  - cec-gpios: gpio that the CEC line is connected to. The line should be
+    tagged as open drain.
+
+If the CEC line is associated with an HDMI receiver/transmitter, then the
+following property is also required:
+
+  - hdmi-phandle - phandle to the HDMI controller, see also cec.txt.
+
+If the CEC line is not associated with an HDMI receiver/transmitter, then
+the following property is optional and can be used for debugging HPD changes:
+
+  - hpd-gpios: gpio that the HPD line is connected to.
+
+This property is optional and can be used for debugging changes on the 5V line:
+
+  - v5-gpios: gpio that the 5V line is connected to.
+
+Example for the Raspberry Pi 3 where the CEC line is connected to
+pin 26 aka BCM7 aka CE1 on the GPIO pin header, the HPD line is
+connected to pin 11 aka BCM17 and the 5V line is connected to pin
+15 aka BCM22 (some level shifter is needed for the HPD and 5V lines!):
+
+#include <dt-bindings/gpio/gpio.h>
+
+cec-gpio {
+	compatible = "cec-gpio";
+	cec-gpios = <&gpio 7 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>;
+	hpd-gpios = <&gpio 17 GPIO_ACTIVE_HIGH>;
+	v5-gpios = <&gpio 22 GPIO_ACTIVE_HIGH>;
+};