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dontpokebearz

macrumors regular
Original poster
Feb 16, 2018
155
108
Maine
Hi all,

Has anyone experienced USB, BT and other externally connected devices not connecting when plugged in? Often a restart will fix the issue, but only if the device is connected during the reboot. I'm talking anything I plug into either the front USB ports and a PCIe USB 3.0 board in the back. Often BT is effected by this as well.

I'm running Monterey 12.5.1 with Open Core legacy Patcher. If I need more details listed, let me know.
 

tsialex

Contributor
Jun 13, 2016
13,218
13,394
The problem lies with the old and obsolete USB controllers of MacPro5,1, that use OHCI for USB1.0 and USB1.1 connections and EHCI for USB2.0. Apple completely removed support for OHCI USB controllers, since no modern Mac have it, from Big Sur forward.

So, any USB devices (usually HumanInterfaceDevices) that connect via USB1.0/1.1 to the MacPro5,1 OHCI/EHCI ports need to be connected via a USB 2.0 (or USB 3.0) hub to force EHCI instead of OHCI and workaround the removal of hot-pluging.

If you don't connect your USB devices via a hub, you will have to connect everything before power-up. When you connect via a hub, the connection will be EHCI and hot plug works again.
 

tsialex

Contributor
Jun 13, 2016
13,218
13,394
Btw, it's easy to know which devices are OHCI, with SystemInformation, open the device you want to know if it's OHCI or EHCI and look at Speed:, if it's Speed: Up to 12 Mb/s, it's an OHCI device, like the original MacPro5,1 BRCM2046 BT controller below:

Code:
BRCM2046 Hub:

  Product ID:    0x4500
  Vendor ID:    0x0a5c  (Broadcom Corp.)
  Version:    1.00
  Speed:    Up to 12 Mb/s
  Manufacturer:    Apple Inc.
  Location ID:    0x5a100000 / 1
  Current Available (mA):    500
  Current Required (mA):    94
  Extra Operating Current (mA):    0
  Built-In:    Yes

Bluetooth USB Host Controller:

  Product ID:    0x8215
  Vendor ID:    0x05ac (Apple Inc.)
  Version:    2.08
  Serial Number:    002500C56DD9
  Speed:    Up to 12 Mb/s
  Manufacturer:    Apple Inc.
  Location ID:    0x5a110000 / 2
  Current Available (mA):    500
  Current Required (mA):    0
  Extra Operating Current (mA):    0
  Built-In:    Yes

For BT devices, unless you install a hub between the backplane and the BRCM2046 BT controller, messy and complicated, you need to upgrade to a still supported AirPort Extreme card, BCM9460CD.

 
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