Layerscape中的主题 Re: Using IRQ00 - IRQ02 pins as a peripheral interrupt

Using IRQ00 - IRQ02 pins as a peripheral interrupt

mehdi-cubic — Tue, 28 May 2024 10:12:08 GMT

I am using LS1043A (on a custom board), where IRQ00 is connected to the INT line of a GPIO expander chip (PCA9506).
In this scenario, I am not sure if it is possible to have a device-tree node for the existing Kernel driver pca953x

So, is it possible to use the IRQ00 - IRQ03 (external INT) pins for this purpose like a normal GPIO interrupt?
Looking at the LS1043ARM.pdf (Table B-1 - p2500 in Rev6), my impression is that these pins are designed for an external wake-up (only?).
The example device-tree in the above link is using a GPIO address like this: 'gpio99: gpio@22', but is this possible with IRQ00, or should this line be rewired to a different GPIO?
If this is possible, could you please suggest a device-tree entry.
I have also seen this post on the subject.

Your help is appreciated.

Re: Using IRQ00 - IRQ02 pins as a peripheral interrupt

SebastianG — Fri, 31 May 2024 22:28:26 GMT

Hi @mehdi-cubic,

Regarding to the question "So, is it possible to use the IRQ00 - IRQ03 (external INT) pins for this purpose like a normal GPIO interrupt?"

Yes, It possible to use just the IRQ03 as a GPIO interrupt.

Regarding to the question "Looking at the LS1043ARM.pdf (Table B-1 - p2500 in Rev6), my impression is that these pins are designed for an external wake-up (only?)."

The pins IRQ00 to IRQ02 is only for external wake up, the only one that can be possible to use as a GPIO is IRQ03.

Regarding to the question "The example device-tree in the above link is using a GPIO address like this: 'gpio99: gpio@22', but is this possible with IRQ00, or should this line be rewired to a different GPIO?"

In the next response I will response this question

Regards,

Sebastian