About IPU IO direction in i.MX6DQ.

[keitanagashima]

Dear All,

Hello.

Refer to Table 37-6. IPU1 External Signals in IMX6DQRM(Rev.2) [p.2748].

Direction of IPU1_DISP0_DATA00 is "IO".

For example, when one select the MUX_MODE = 000 (ALT0— Select signal IPU1_DISP0_DATA00) in IOMUXC_SW_MUX_CTL_PAD_DISP0_DATA00 at u-boot, which initial direction is it input or output?

I'd like to know the other "IO" signals, too.

Best Regards,

Keita

[gusarambula]

Hello Keita Nagashima,

I was checking this table and the while these pins are listed as IO configurable, the IPU Display pins are used as outputs in all configurations I know. Whenever video needs to be feed to the IPU the CSI/MIPI interfaces should be used. I would expect these to work similarly to the HDMI module which works as output only.

I will double check and in case it’s a documentation error I’ll escalate so it gets addressed on the next release of the documentation.

Regardless, I would like to ask what is your application and what guidance can we give? If you wish to input video I would strongly suggest the CSI/MIPI interfaces as I mentioned.

[keitanagashima]

Hi gusambula,

Thank you for your reply.

My customer's application is Automotive Infortainment.

Of cause, they will use the IPU1_DISP0_DATA00 pin as output for Display.

I'm wondering if why is exist input direction in IPU1_DISP0_DATA00 pin.

And, I'd like to know the default direction setting (input or output) after selecting the IOMUX (ALT) in u-boot.

Best Regards,

Keita

[gusarambula]

Hello Keita Nagashima,

Thanks for the additional information. I’ll investigate why the dual direction is listed and I’ll let you know as soon as I have more information.

As a side note, the table lists signals, so I would be careful with that. Some of these signals are not the default muxing option of the Pad. That being said, in the case of the Display signals their default direction setting would be output after selecting the IOMUX (ALT) in u-boot. I’m double checking why they appear as having an input option.

[keitanagashima]

Hi gusarambula,

Do you have any update about below things?

> I’ll investigate why the dual direction is listed and I’ll let you know as soon as I have more information.

> I’m double checking why they appear as having an input option.

Best Regards,

Keita

[gusarambula · Accepted solution]

Hello Keita Nagashima,

My apologies. I confirmed that the direction for these signals is Output. The reason why there is a I/O on these signals may be related to the internal PADs but these signals are used as Output only.

[keitanagashima]

Hi gusarambula,

OK. Thank you very much.

Best Regards,

Keita