Hello, I am trying to use a PI7C9X440SL PCIe/USB adapter on Qualcomm sdm845 platform. This PCIe device does not support MSI interrupts. On 5.10 kernel, the pci device is detected but EHCI driver probe fails with this message "Found HC with no IRQ. Check BIOS/PCI". lspci shows that legacy interrupt cannot be found: #lspci -vv -nk -s 0000:03:00.2 0000:03:00.2 0c03: 12d8:400f (rev 01) (prog-if 20 [EHCI]) Subsystem: 12d8:400f Control: I/O- Mem+ BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Interrupt: pin C routed to IRQ 0 Region 0: Memory at 60302000 (32-bit, non-prefetchable) [size=256] Capabilities: [80] Power Management version 3 Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=375mA PME(D0+,D1+,D2+,D3hot+,D3cold+) Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME- Capabilities: [8c] MSI: Enable- Count=1/1 Maskable- 64bit- Address: 00000000 Data: 0000 Capabilities: [e0] Express (v1) Legacy Endpoint, MSI 00 DevCap: MaxPayload 256 bytes, PhantFunc 0, Latency L0s <64ns, L1 <1us ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset- DevCtl: CorrErr- NonFatalErr- FatalErr- UnsupReq- RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop- MaxPayload 128 bytes, MaxReadReq 128 bytes DevSta: CorrErr- NonFatalErr- FatalErr- UnsupReq- AuxPwr+ TransPend- LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s, Exit Latency L0s <512ns ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp- LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk- ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt- LnkSta: Speed 2.5GT/s (ok), Width x1 (ok) TrErr- Train- SlotClk- DLActive- BWMgmt- ABWMgmt- It is not clear to me if legacy interrupts are supported by the pcie-qcom driver. Do I need to add the PCIe/USB device description in the device tree for this to work ? Thank you. Pierre Le Magourou