Hi,
I am working with iMX8MM EVK and Yocto distribution 4.19.35 version
Build Configuration:
BB_VERSION = "1.42.0"
BUILD_SYS = "x86_64-linux"
NATIVELSBSTRING = "ubuntu-16.04"
TARGET_SYS = "aarch64-poky-linux"
MACHINE = "imx8mmevk"
DISTRO = "fsl-imx-xwayland"
DISTRO_VERSION = "4.19-warrior"
TUNE_FEATURES = "aarch64"
TARGET_FPU = ""
We have interfaced two keypad boards interfaced to the IMX8MMEVK to PCA6416 IO expander.
we have followed the steps mentioned in the below thread for setting up the GPIO1_IO12 interrupt line.
How to enable interrupts of EXP_GPIOs from PCA6416 in IMX8M Mini EVK
From the datasheet of PCA6416A section 7.8 Interrupt output (INT)
"The INT output has an open-drain structure and requires pull-up resistor to VDD(P) or
VDD(I2C-bus) depending on the application. INT should be connected to the voltage source
of the device that requires the interrupt information"
https://community.nxp.com/thread/518153
Frpm the above thread, we have enabled the pull-up resistor internally to GPIO1_IO12 in the fsl-imx8mm-evk.dts
pinctrl_i2c2_dev: mydev_iogrp {
fsl,pins = <
MX8MM_IOMUXC_GPIO1_IO12_GPIO1_IO12 0x14f /* instead of 0x19 i programmed 0x14F */
>;
};
My first question:
Is my configuration of pad ctrl register value is correct? 0x14F, Please let me know, because i am yet to get the hw to test, before that i am making sure my driver code is perfect.
My second question:
The interrupt line GPIO1_IO12 is shared. The interrupt (Active Low) is generated whenever there is a state change at the EXP_IO Input Interrupt signals. I have registered the two irq handlers for IRQ_TYPE_LEVEL_LOW for GPIO1_IO12.
IRQ_Handler1 - EXP_IO8 for Rising Edge
IRQ_Handler2 - EXP_IO10 for Falling Edge
In the respective irq_handlers i will read the values of EXP_IO8 and EXP_IO10 for value and conclude on the edge.
is my understanding is correct?
Thank you, Sreedhar
Solved! Go to Solution.
Hi Sreedhar
1. configuration of pad ctrl register value is correct.
2. I believe your understanding is correct.
Best regards
igor
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------
Hi Sreedhar
1. configuration of pad ctrl register value is correct.
2. I believe your understanding is correct.
Best regards
igor
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------
Thank you igor !!