​Following reports from a number of users the issue reported below appears to be addressed in 10.15.4.
Since upgrading to MacOSX 10.15 a number of users have reported that touch has stopped working on systems that previous worked OK.
In specific cases we have observed that although the device appears in the system report is not correctly listed as in this example below:
Full listing (working) |
Partial listing (not working) |
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In cases whereby the device as been partially listed touch has not worked. This has thus far been seen with Acer T232Hxx/T272Hxx and Samsung S24C770 monitors.
For the above partial listing device to work it should list as below (this is taken from a 10.15 system with 2 x identical touch devices, one listed in full and one partial!):
Here is another example of two touch devices that list OK without UPDD installed and differently with UPDD installed (2 x incomplete listings!!):
Working |
2149/2122 device not working |
|
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There is a possibility that the device is adversely reacting to our software device reset function that we use to reenumerate the device list at driver load. We do have a setting 'disable_initial_claim_device' to disable this reset feature but this might mean that a reboot is required after install before the driver can access the device.
We can supply a driver with this setting enabled or it can be set with the command 'upddutils nodevice set disable_initial_claim_device 1' followed by a reboot.
If this does not fix the issue then we do not know why this is occurring. It seems to be intermittent in that sometimes it works and after a reboot it doesn't. Switching cables and ports may make it work for a while.
It could be a bug in a minor release of 10.15 relating to the USB stack which may be fixed in a later release. Some users have reported all started working with latest 10.15.4 release.
Until we find the definitive reason we can only second guess! Apple post this advise about USB issues.
Inevitably with UPDD installed and handling the USB device the USB 'chatter' will be different to the standard native HID driver chatter and this seems to have a negative effect on some devices in MacOS 10.15.