TMDSEVM572X: Command to see HDMI Devices

Hi Adam,

Which OS are you running? Are you running Linux or RTOS?

Regards,

Karan

Hi Karan,

We are running the dev board with the Linux Kernel and Android that the TI sdk provided. We also were wondering if the development board DTS has the hdmi_cec pinctrl set.

Thanks,
Adam

Thanks. Do you know if the HDMI-Cec Pinctrol is enabled on the am57xx dev board by default?

Check the pinmux configuration in u-boot file board/ti/am57xx/mux_data.h

Thanks! We do see hdmi1_cec in pin control in the mux_data.h file that you told us to look into. Would it be enabled on the pre-built image? Also, does the Ti dev kit hardware support the Cec?

Best,

Adam

Yes, it  should be enabled in pre built image.

Thank you!

It is our understanding that we would need a HDMI driver that support CeC, which in turn would use the TI pin control. Could you please let us know what graphic driver is currently being used in the evm or where to find it?

Best,
Adam

Hi Adam,

AM572x has SGX544 3D graphics core. The driver is part of the SDK.
https://www.ti.com/lit/ds/symlink/am5728.pdf

Regarding CEC, the pin is there, I am not sure about HDMI driver supporting CEC.

Regards,
Vishal

Thanks you for all the help Vishal. 

We wanted to check in and see if you could help us understand the CeC functionality better. We have enabled the CeC_Core in our Kconfig. We also see the OMAP4_DSS_HDMI_CEC config is enabled as well. It is our understanding that this would mean the kernel module for cec.ko and the hdmi4_cec.ko modules would be built into the kernel. We have successfully built the SDK with these configs and have flashed them to the dev kit. We were able to see the proc/config.gz and they are indeed enabled.

We are now having an issue because either of those modules should have created a /dev/cecX device. We do not see one. We are not sure what we are missing and decided to reach out to you for some help.

Best,

Adam

Thanks for the reply!

Do you know the reason why the AM572x device dropped support for CeC?

thanks!

Sorry, don't know the reason.

Would it be possible for me to port the CeC code over to the hdmi5*.c files? I glanced over the hdmi4_cec.c file and saw a few hard coded constants. I am not sure if they would change between omap4 and omap5.

Hi,

It won't be possible as there are some additional HDMI IP documentation that would be needed. These are not available in public.

Regards,
Vishal

Thanks for the reply! Do you know if TI is planning on adding in the cec support to omap5?

No plans to add the support.

Thank you for the quick reply!