I'm trying to use UART1_RX (ball L31) on an i.MX8XQuadPlus processor. I have the device tree pinctrl setup as follows:
IMX8QXP_UART1_RX_LSIO_GPT1_CLK 0x26000060 // IMX8_FREQ_IN
This should be GPIO0 pin 22:
I have a 1 Hz square wave being fed into this pin.
But when I try to read this pin in Linux it always reads low:
root@imx8qxpdeere:~# gpioget gpiochip0 22
0
root@imx8qxpdeere:~# gpioget gpiochip0 22
0
root@imx8qxpdeere:~# gpioget gpiochip0 22
0
root@imx8qxpdeere:~# gpioget gpiochip0 22
0
root@imx8qxpdeere:~# gpioget gpiochip0 22
0
root@imx8qxpdeere:~# gpioget gpiochip0 22
0
root@imx8qxpdeere:~# gpioget gpiochip0 22
0
I looked through the errata and didn't see any mention of a GPIO pin.
Any ideas?
已解决! 转到解答。
I had copied and pasted the wrong #define:
#define IMX8QXP_UART1_RX_LSIO_GPT1_CLK IMX8QXP_UART1_RX 3
#define IMX8QXP_UART1_RX_LSIO_GPIO0_IO22 IMX8QXP_UART1_RX 4
I used the former, when I meant to use the later.
I had copied and pasted the wrong #define:
#define IMX8QXP_UART1_RX_LSIO_GPT1_CLK IMX8QXP_UART1_RX 3
#define IMX8QXP_UART1_RX_LSIO_GPIO0_IO22 IMX8QXP_UART1_RX 4
I used the former, when I meant to use the later.