From: Manuel Lauss Date: Thu, 30 Apr 2026 13:58:22 +0000 (+0200) Subject: serial: 8250_port: recognize UPIO_AU X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=49fa670efdfdd27e29145cbd2beef065c08717ef;p=thirdparty%2Fkernel%2Flinux.git serial: 8250_port: recognize UPIO_AU My MIPS Alchemy systems generate the following warning during probe of the 8250 driver: WARNING: drivers/tty/serial/8250/8250_port.c:462 at set_io_from_upio+0xfc/0x124, CPU#0: swapper/0/1 Unsupported UART type 4 [...] [<80521d40>] set_io_from_upio+0xfc/0x124 [<80521dfc>] serial8250_set_defaults+0x94/0xe0 [<80520fb4>] serial8250_register_8250_port+0x288/0x51c [<805214ec>] serial8250_probe+0x160/0x1e8 [<8053b5f0>] platform_probe+0x64/0x90 The least invasive fix is to recognize UPIO_AU (type 4) in set_io_from_upio() and do nothing, since all parameters have already been set up in 8250_rt288x.c::au_platform_setup(). Run-tested on Alchemy Au1300 platform. Signed-off-by: Manuel Lauss Link: https://patch.msgid.link/20260430135822.905035-1-manuel.lauss@gmail.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index af78cc02f38e..02e6cdefdbac 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -458,6 +458,8 @@ static void set_io_from_upio(struct uart_port *p) p->serial_out = io_serial_out; break; #endif + case UPIO_AU: + break; default: WARN(p->iotype != UPIO_PORT || p->iobase, "Unsupported UART type %x\n", p->iotype);