No idea whether the CPU used in the Librems have the ASMedia chipset. It looks like ASMedia makes things related to peripheral devices (USB, SATA, etc.) so a simple lspci should show some information. Here’s an output of the command from this post:
00:00.0 Host bridge: Intel Corporation Skylake Host Bridge/DRAM Registers (rev 08)
00:02.0 VGA compatible controller: Intel Corporation HD Graphics 520 (rev 07)
00:04.0 Signal processing controller: Intel Corporation Skylake Processor Thermal Subsystem (rev 08)
00:05.0 Multimedia controller: Intel Corporation Skylake Imaging Unit (rev 01)
00:08.0 System peripheral: Intel Corporation Skylake Gaussian Mixture Model
00:14.0 USB controller: Intel Corporation Sunrise Point-LP USB 3.0 xHCI Controller (rev 21)
00:14.2 Signal processing controller: Intel Corporation Sunrise Point-LP Thermal subsystem (rev 21)
00:17.0 SATA controller: Intel Corporation Sunrise Point-LP SATA Controller [AHCI mode] (rev 21)
00:1c.0 PCI bridge: Intel Corporation Sunrise Point-LP PCI Express Root Port #5 (rev f1)
00:1f.0 ISA bridge: Intel Corporation Sunrise Point-LP LPC Controller (rev 21)
00:1f.2 Memory controller: Intel Corporation Sunrise Point-LP PMC (rev 21)
00:1f.3 Audio device: Intel Corporation Sunrise Point-LP HD Audio (rev 21)
00:1f.4 SMBus: Intel Corporation Sunrise Point-LP SMBus (rev 21)
00:1f.5 Non-VGA unclassified device: Intel Corporation Device 9d24 (rev 21)
01:00.0 Network controller: Qualcomm Atheros AR9462 Wireless Network Adapter (rev 01)
It doesn’t seem like the Librem has any ASMedia ports here, yet for all we now the Intel SATA and USB controllers could be using them. Though, we have little information to where this backdoor is present (ie if it’s present in Intel chips or not), so I think right now we can’t tell.