media: tegra-cec: add Tegra HDMI CEC driver

This driver adds support for the Tegra CEC IP. It is based on the
NVIDIA drivers/misc/tegra-cec driver in their 3.10 kernel.

This has been converted to the CEC framework and cleaned up.

Tested with my Jetson TK1 board. It has also been tested with the
Tegra X1 in an embedded product.

Note of warning for the Tegra X2: this SoC supports two HDMI outputs,
but only one CEC adapter and the CEC bus is shared between the
two outputs. This is a design mistake and the CEC adapter can
control only one HDMI output. Never hook up both HDMI outputs
to the CEC bus in a hardware design: this is illegal as per the
CEC specification.

The CEC bus can be shared between multiple inputs and zero or one
outputs, but not between multiple outputs.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
index 2dc1d8fe4f5f..fd0c99859d6f 100644
--- a/drivers/media/platform/Kconfig
+++ b/drivers/media/platform/Kconfig
@@ -614,6 +614,17 @@ config VIDEO_STM32_HDMI_CEC
          CEC bus is present in the HDMI connector and enables communication
          between compatible devices.
 
+config VIDEO_TEGRA_HDMI_CEC
+       tristate "Tegra HDMI CEC driver"
+       depends on ARCH_TEGRA || COMPILE_TEST
+       select CEC_CORE
+       select CEC_NOTIFIER
+       ---help---
+         This is a driver for the Tegra HDMI CEC interface. It uses the
+         generic CEC framework interface.
+         The CEC bus is present in the HDMI connector and enables communication
+         between compatible devices.
+
 endif #CEC_PLATFORM_DRIVERS
 
 menuconfig SDR_PLATFORM_DRIVERS