Hello all,
I tested 2 days ago my Risingcam IMX571 on the RPi4. Was working fine with it.
Yesterday I made an update/upgrade of the system.
The result is that the driver hangs and the camera is not even seen by Ekos.
I recompiled all on my RPi4 device with same result. Drivers hang on getting properties .

<strong>The system:</strong>
No LSB modules are available.
Distributor ID:    Ubuntu
Description:    Ubuntu 20.04.3 LTS
Release:    20.04
Codename:    focal

<strong>The cam is detected by the system:</strong>
<strong>Before plug it in:</strong>
ubuntu@NAFABox:~$ lsusb
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 003: ID 0bda:8179 Realtek Semiconductor Corp. RTL8188EUS 802.11n Wireless Network Adapter
Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

<strong>After plug it in:</strong>
ubuntu@NAFABox:~$ lsusb
Bus 002 Device 002: ID 0547:12b7 Anchor Chips, Inc. USB3.0 Camera
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 003: ID 0bda:8179 Realtek Semiconductor Corp. RTL8188EUS 802.11n Wireless Network Adapter
Bus 001 Device 006: ID 1a40:0101 Terminus Technology Inc. Hub
Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

<strong>The driver answer:</strong>
ubuntu@NAFABox:~$ indiserver -vvv indi_toupcam_ccd
2021-08-30T05:36:08: startup: indiserver -vvv indi_toupcam_ccd
2021-08-30T05:36:08: Driver indi_toupcam_ccd: pid=7500 rfd=3 wfd=6 efd=7
2021-08-30T05:36:08: listening to port 7624 on fd 4
2021-08-30T05:36:08: Driver indi_toupcam_ccd: sending msg copy 1 nq 1:
<getProperties version='1.7'/>

And hangs on getProperties.
 

Well, nobody answered, so I suppose that nobody has the answer.
For those that could meet the problem I can provide a temporary answer : I used INDIGO_SERVER that recognize the cam and seems to works well.
So there might be some weird issues with last INDI drivers. I don't ever see what it is.
 

I resolved my issue with a Rising Cam by copying the static library libtoupcam.so provided with PHD2 source code into /usr/lib/aarch64-linux-gnu. And then recompiled the driver.