Raspberry Pi Zero: act as USB mass storage using power port, use data USB port for Wi-Fi

Question

I have a Raspberry Pi Zero (1.3) running Debian Jessie (full); the image name is 2016-05-27-raspbian-jessie.img. I've ran apt-get update && apt-get upgrade and updated the packages on it.

I have it connected to my laptop (Mac) with an OTG data cable, connected to the power port on the Raspberry Pi Zero. I connected a Wi-Fi adapter to the Raspberry Pi Zero data USB port, which I use to SSH into it (the Wi-Fi works fine).

I'm trying to make it act as a mass storage device, with g_mass_storage, following the instructions here. However, trying to do so, my Raspberry Pi Zero "hangs"—

$ sudo modprobe g_mass_storage file=/piusb.bin stall=0
packet_write_wait: Connection to 192.168.0.6 port 22: Broken pipe

I have two questions.

1. Is what I want feasible? Ie, can I use the power port to transfer data from a connected machine to the Raspberry Pi Zero in mass storage mode, while still using it to connect to the Wi-Fi by having a Wi-Fi adapter connected to the data port?
2. Why does it hang, is this expected (ie, the data port must be used for USB mass storage, and cannot operate as a Wi-Fi adapter once the g_mass_storage module is loaded)?

Answer 1

can I use the power port to transfer data

Your plan on using the power port as data already failed. No, the power port is power only.

---

Here's another plan:

                     /-> Wifi Adapter
Pi Zero <-> USB hub <
                     \-> male-to-male USB cable plugged to the PC

OTG does not allow being a master and a slave at the same time, so a hub would not work.

---

Your best bet would be to do everything involving data over WiFi (FTP, Samba, etc.) An alternative would be via Ethernet. This will effectively turn your Pi Zero into a Wired/Wireless NAS.