The data pin about sd card can't be pull down or up without sd card, why?

When I insert the SD card , SDCARD_DAT0_POL, SDCARD_DAT1_POL, SDCARD_DAT2_POL, SDCARD_DAT3_POL can be pull down or up, but if there is no SD card, these pin would can’t control. Why?

Hi, please share more details, how you pull down/up the pin?

1.request the pin as gpio
2.export the GPIO through sysfs
3.set the gpio to output through the node
4.pull down/up the pin through the node
5.measure the level through an oscilloscope
And then I found that, SDCARD_DAT0_POL, SDCARD_DAT1_POL, SDCARD_DAT2_POL, SDCARD_DAT3_POL can’t be pull down/up without sd card.

These pins should NOT be configured as GPIOs, please follow Pinmux sheet.