PROCESSOR-SDK-AM62X: Which GPIO support low level interrupt trigger on AM62x?

kinghom liao

Part Number: PROCESSOR-SDK-AM62X
Other Parts Discussed in Thread: TCAN4550

I am using AM62x processor and ti,tcan4550 spi to can module, but I found AM62x doesn't support low level trigger intterupt, at the same time, ti,tcan4550 spi to can module only support low level trigger intterupt. There are some snaps with reguard to the register of configuration of GPIO interrupt on AM62x processor, and the describe of nINT about ti,tcan4550 spi to can module.

My queston is: how can I deal with this issue? And which GPIO support low level interrupt trigger on AM62x? Thankyou.

Below picture is the result which I apply IRQ_TYPE_LEVEL_LOW in dts. It can be find out that AM62x dosen't support IRQ_TYPE_LEVEL_LOW trigger method.

over 2 years ago

0 Bin Liu over 2 years ago

TI__Guru**** 167931 points

Hi Kinghom,

The GPIO interrupt is edge triggered. Do you have any issue in GPIO interrupts with tcan4550 nINT pin?

0 kinghom liao over 2 years ago in reply to Bin Liu

Prodigy 90 points

Well, AM62x GPIO (include MAIN_GPIO and MCU_GPIO) only support edge triggered, and tcan4550 nINT only support low level. Does that mean tcan4550 can not use on AM62x processor? Below is an example about how to configure tcan4550 in dts, This example show that tcan4550 need to support low level triggered.

Looking forward to your reply, Thankyou.

0 Bin Liu over 2 years ago in reply to kinghom liao

TI__Guru**** 167931 points

Hi Kinghom,

I am confused, do you want AM62x to generate an interrupt to tcan4550? or the other way around, you want tcan4550 to generate interrupt to AM62x?

The AM62x GPIO interrupt meant AM62x to receive interrupt from a GPIO pin driven by an external signal. Well your tcan4x5x device tree example seems to describe the interrupt received by tcan4550. Do I miss anything?

0 kinghom liao over 2 years ago in reply to Bin Liu

Prodigy 90 points

I want tcan4550 to generate interrupt to AM62x, but tcan4550's nINT pin only support low level triggered, at the sametime, AM62x's GPIO only support edge triggered.

0 Bin Liu over 2 years ago in reply to kinghom liao

TI__Guru**** 167931 points

When nINT transits from high to low, it will trigger an interrupt on AM62x GPIO pin which nINT is connected to.

0 kinghom liao over 2 years ago in reply to Bin Liu

Prodigy 90 points

All right, I have tested this connection, and I found AM62x didn't receive or transfer data continuously, it only received or transfer one frame, and then nINT pull down, the tcan4550 driver didn't trigger interrupt anymore because 0f AM62x GPIO pin only support edge triggered. Right now, I need to change tcan4550 driver to entry interrupt when nINT pull down.

0 Bin Liu over 2 years ago in reply to kinghom liao

TI__Guru**** 167931 points

Kinghom,

I am curious why you use tcan4550? The AM62x already has a MCAN module, you just need to add a CAN FD transceiver. Is there any reason you don't want to use the AM62x MCAN module?

0 kinghom liao over 2 years ago in reply to Bin Liu

Prodigy 90 points

I have used AM62x MCAN module, but I need 8 CAN modules in my application, it no enough CAN module on AM62x, so I need to use tcan4550 to expand CAN module.

0 Mukul Bhatnagar over 2 years ago in reply to kinghom liao

TI__Guru* 83815 points

Please see if this post helps

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1084211/am6442-tcan4550-driver/4072272#4072272

Processors

Processors forum

PROCESSOR-SDK-AM62X: Which GPIO support low level interrupt trigger on AM62x?