pci1xxxx is a PCIe switch with a multi-function endpoint on one of its downstream ports. Quad-uart is one of the functions in the multi-function endpoint. This patch adds device driver for the quad-uart function and enumerates between 1 to 4 instances of uarts based on the PCIe subsystem device ID. The changes from v1 are mentioned in each patch in the patchset. Thanks to Andy Shevchenko, Ilpo Jarvinen, Geert Uytterhoeven for their review comments for v1. Kumaravel Thiagarajan (3): 8250: microchip: pci1xxxx: Add driver for quad-uart support. 8250: microchip: pci1xxxx: Add rs485 support to quad-uart driver. 8250: microchip: pci1xxxx: Add power management functions to quad-uart driver. MAINTAINERS | 6 + drivers/tty/serial/8250/8250_pci1xxxx.c | 563 ++++++++++++++++++++++++ drivers/tty/serial/8250/8250_port.c | 8 + drivers/tty/serial/8250/Kconfig | 10 + drivers/tty/serial/8250/Makefile | 1 + include/uapi/linux/serial_core.h | 3 + 6 files changed, 591 insertions(+) create mode 100644 drivers/tty/serial/8250/8250_pci1xxxx.c -- 2.25.1