mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-24 01:53:15 +07:00
fbf8ad7ef4
In order to debug the HDMI 5V line we need to add a new v5-gpios property. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
43 lines
1.5 KiB
Plaintext
43 lines
1.5 KiB
Plaintext
* 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>;
|
|
};
|