That really helps.  Now I know which file to edit to add that extra option.  Unfortunately, it didn't help. 

What does "--bet-clk 20" do?  I don't think I've seen that command before.

As far as you thinking that your USB adapter is broke, do you get the same results as I do when I run the following below?  It's like you said, cgminer detects it, but like you, when I look in Minera, it says "No local devices found".  I've used 2 different USB adapters with the same results
minera@minera /var/www/minera/minera-bin $ cgminer -n
 [2015-12-09 22:36:51.130] USB all: found 4 devices - listing known devices
.USB dev 0: Bus 1 Device 4 ID: 10c4:ea60
  Manufacturer: 'Silicon Labs'
  Product: 'CP2102 USB to UART Bridge Controller'
 [2015-12-09 22:36:51.133] 1 known USB devices

Does your boot log show anything useful?
minera@minera /var/www/minera/minera-bin $ dmesg
I get a whole bunch of this.
[ 4114.924623] cp210x 1-1.2:1.0: cp210x converter detected
[ 4114.929049] usb 1-1.2: cp210x converter now attached to ttyUSB0
[ 4121.220096] cp210x ttyUSB0: cp210x converter now disconnected from ttyUSB0

Did you ever get Minera working?

How do you compile cgminer?  Sorry, I'm a noob and wasn't able to find that information or which directory it's supposed to be run from in RPi.  What would the command be?  From what I've read, you have to enable the block-erupter when you use Minera because the default is set to disabled.

When I bought my Prisma, it came with the RPi and Minera installed so I didn't have to do anything to get it working.  But, from what I've read from michelem's github, all you're supposed to do is put the image file onto your SD card and then you should be able to access it via http://<IP address that's assigned to it>/minera
https://github.com/michelem09/minera

Within the Minera app, when you go to Settings, Local Miner, it lets you "Select your preferred miner software" with the options of CPUminer (GC3355 fork), BFGminer 5.x (Official), CGminer 4.x (Official), and CGminer (Dmaxl Zeus fork).  I've selected CGminer 4.x (Official) but it doesn't recognize my Prisma.

If you broke the cgminers, you should be able to rebuild it by:
cd /var/www/minera
./build_miner.sh <miner-name>

That's included in the link above too, under the section "Building miner software".

I agree, it is very annoying not being able to set it up easily.  I've read a lot of people having difficulties too. 

Hi everybody.  I'm new to Bitcoin mining and recently purchased an Antminer S3 and an ASICMiner Prisma.  I got the S3 up and running with no problems, however the Prisma is giving me a lot of difficulties.  It's a version 1.0, with a USB adapter to a Raspberry Pi with the latest Minera update installed.  I followed Dogie's Comprehensive setup and have searched everywhere for a possible solution but to no avail.  Within Minera, it says "No local devices found".  I tried connecting only one of the boards and also 2 separate USB adapters, but it still won't work.  I read online that you're supposed to --enable-blockerupter but I'm not sure where I'm supposed to run that.  Any help would be greatly appreciated!