簡單來講, 今天你把一個regulator配給一個driver. 背後的意義就是你要讓這driver去幫你控制開關.
所以正常來講, gpio level的確在你插拔sd卡的時候會改變
但其實always-on的VDD可以比較好debug你其他部份… 尤其是在你不知道有沒有其他硬體問題的時候…
其實forum上用always-on VDD的用戶是比較多的.
Basically, assigning a regulator to a driver means you want this driver to help you control the ON/OFF. Thus, the gpio should change level when you hotplug the sdcard.
But a always-on VDD case would be easier for us to debug your reset hardware… especially when you have no idea whether your carrier board design is correctly or not.