Hi Mika, > > > In one of our boards we have an add-on PCI board, with a PCI serial > device > > > Exar XR17V352. This device also contains 16 gpios. > > > The exar device drivers work good, both the "8250_exar" and the > "gpio_exar", and > > > I can manage the exar's gpios correctly. > > > The problem is how to assign the gpio-line-names property to a PCI > gpio > > > expanders like this. > > > > > > I tried adding a new device in my ACPI configuration, as: > > > > > > Device (EXAR) > > > { > > > Name (_HID, "13A80352") > > If this is PCI device then you need to have _ADR here instead of _HID. the problem is that the parent bus of this device is not declared in any ACPI table. The exar chip is on the bus 7 : 07:00.0 Serial controller: Exar Corp. XR17V3521 Dual PCIe UART (rev 03) and in the _ADR object you can specify device and function only. How can I specify the parent bus? It is not simple … The lspci output is the following: root@debian:/etc# lspci 00:00.0 Host bridge: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series Host Bridge (rev 0d) 00:02.0 VGA compatible controller: Intel Corporation Device 5a85 (rev 0d) 00:0e.0 Audio device: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series Audio Cluster (rev 0d) 00:0f.0 Communication controller: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series Trusted Execution Engine (rev 0d) 00:12.0 SATA controller: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series SATA AHCI Controller (rev 0d) 00:13.0 PCI bridge: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series PCI Express Port A #1 (rev fd) 00:13.1 PCI bridge: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series PCI Express Port A #2 (rev fd) 00:13.2 PCI bridge: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series PCI Express Port A #3 (rev fd) 00:14.0 PCI bridge: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series PCI Express Port B #1 (rev fd) 00:14.1 PCI bridge: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series PCI Express Port B #2 (rev fd) 00:15.0 USB controller: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series USB xHCI (rev 0d) 00:16.0 Signal processing controller: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series I2C Controller #1 (rev 0d) 00:16.1 Signal processing controller: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series I2C Controller #2 (rev 0d) 00:19.0 Signal processing controller: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series SPI Controller #1 (rev 0d) 00:19.1 Signal processing controller: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series SPI Controller #2 (rev 0d) 00:19.2 Signal processing controller: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series SPI Controller #3 (rev 0d) 00:1f.0 ISA bridge: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series Low Pin Count Interface (rev 0d) 00:1f.1 SMBus: Intel Corporation Atom/Celeron/Pentium Processor N4200/N3350/E3900 Series SMBus Controller (rev 0d) 01:00.0 Ethernet controller: Intel Corporation I210 Gigabit Network Connection (rev 03) 02:00.0 Ethernet controller: Intel Corporation I210 Gigabit Network Connection (rev 03) 04:00.0 Ethernet controller: Intel Corporation I210 Gigabit Network Connection (rev 03) 05:00.0 PCI bridge: Pericom Semiconductor Device 2404 (rev 05) 06:01.0 PCI bridge: Pericom Semiconductor Device 2404 (rev 05) 06:02.0 PCI bridge: Pericom Semiconductor Device 2404 (rev 05) 06:03.0 PCI bridge: Pericom Semiconductor Device 2404 (rev 05) 07:00.0 Serial controller: Exar Corp. XR17V3521 Dual PCIe UART (rev 03) --- Exar serial port 08:00.0 Ethernet controller: Intel Corporation I210 Gigabit Network Connection (rev 03) root@debian:/etc# Thanks, Flavio