[PATCH 6.19 059/220] serial: 8250_pci: add support for the AX99100

Greg Kroah-Hartman
2026-03-23T13:52:28Z

From: Martin Roukala (né Peres) <martin.roukala@mupuf.org>

commit 9c0072bc33d349c83d223e64be30794e11938a6b upstream.

This is found in popular brands such as StarTech.com or Delock, and has
been a source of frustration to quite a few people, if I can trust
Amazon comments complaining about Linux support via the official
out-of-the-tree driver.

Signed-off-by: Martin Roukala (né Peres) <martin.roukala@mupuf.org>
Cc: stable <stable@kernel.org>
Link: https://patch.msgid.link/20260309-8250_pci_ax99100-v1-1-3328bdfd8e94@mupuf.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/tty/serial/8250/8250_pci.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)

--- a/drivers/tty/serial/8250/8250_pci.c
+++ b/drivers/tty/serial/8250/8250_pci.c
@@ -137,6 +137,8 @@ struct serial_private {
};

#define PCI_DEVICE_ID_HPE_PCI_SERIAL 0x37e
+#define PCIE_VENDOR_ID_ASIX 0x125B
+#define PCIE_DEVICE_ID_AX99100 0x9100

static const struct pci_device_id pci_use_msi[] = {
{ PCI_DEVICE_SUB(PCI_VENDOR_ID_NETMOS, PCI_DEVICE_ID_NETMOS_9900,
@@ -149,6 +151,8 @@ static const struct pci_device_id pci_us
0xA000, 0x1000) },
{ PCI_DEVICE_SUB(PCI_VENDOR_ID_HP_3PAR, PCI_DEVICE_ID_HPE_PCI_SERIAL,
PCI_ANY_ID, PCI_ANY_ID) },
+ { PCI_DEVICE_SUB(PCIE_VENDOR_ID_ASIX, PCIE_DEVICE_ID_AX99100,
+ 0xA000, 0x1000) },
{ }
};

@@ -920,6 +924,7 @@ static int pci_netmos_init(struct pci_de
case PCI_DEVICE_ID_NETMOS_9912:
case PCI_DEVICE_ID_NETMOS_9922:
case PCI_DEVICE_ID_NETMOS_9900:
+ case PCIE_DEVICE_ID_AX99100:
num_serial = pci_netmos_9900_numports(dev);
break;

@@ -2555,6 +2560,14 @@ static struct pci_serial_quirk pci_seria
.init = pci_netmos_init,
.setup = pci_netmos_9900_setup,
},
+ {
+ .vendor = PCIE_VENDOR_ID_ASIX,
+ .device = PCI_ANY_ID,
+ .subvendor = PCI_ANY_ID,
+ .subdevice = PCI_ANY_ID,
+ .init = pci_netmos_init,
+ .setup = pci_netmos_9900_setup,
+ },
/*
* EndRun Technologies
*/
@@ -6076,6 +6089,10 @@ static const struct pci_device_id serial
0xA000, 0x3002,
0, 0, pbn_NETMOS9900_2s_115200 },

+ { PCIE_VENDOR_ID_ASIX, PCIE_DEVICE_ID_AX99100,
+ 0xA000, 0x1000,
+ 0, 0, pbn_b0_1_115200 },
+
/*
* Best Connectivity and Rosewill PCI Multi I/O cards
*/