Pin muxing

[Rabiraj]

Hi,
I am using I.MX8M plus based SOC.
In that I wan to use a particular pin for GPIO purpose.
From I.MX8M plus application note document from NXP website, I am able to see in chapter 8, section 8.1 External signals and pin multiplexing .
Page number 1295 , in that port names : HDMI_HPD and HDMI_HPD_O
Are the two pins I am trying to reuse.
How can I find, these pins are connected which GPIO number?
Because I wan to edit my DTS file, 
Can you please help me on this ?

[Zhiming_Liu · Accepted solution]

Hi @Rabiraj 

You can search in arch/arm64/boot/dts/freescale/imx8mp-pinfunc.h

For example, you can reuse HDMI_HPD pad as GPIO3_IO29

#define MX8MP_IOMUXC_HDMI_HPD__HDMIMIX_HDMI_HPD                      0x24C 0x4AC 0x000 0x0 0x0
#define MX8MP_IOMUXC_HDMI_HPD__AUDIOMIX_HDMI_HPD_O                   0x24C 0x4AC 0x000 0x1 0x0
#define MX8MP_IOMUXC_HDMI_HPD__I2C6_SDA                              0x24C 0x4AC 0x5D0 0x3 0x3
#define MX8MP_IOMUXC_HDMI_HPD__CAN2_RX                               0x24C 0x4AC 0x550 0x4 0x3
#define MX8MP_IOMUXC_HDMI_HPD__GPIO3_IO29                            0x24C 0x4AC 0x000 0x5 0x0