https://lab.nexedi.cn/kirr/linux/commit/fa01e2ca9f531b4a5693469a196eb1574b8d7d8a
The 8250_fintek driver advertises as the PNP0501 driver; however this conflicts with the standard 16550A uart PNP0501. The conflict causes the 8250_fintek driver to load with _every_ PNP0501, but never probe, and causing the entire 8250 driver stack to unload if the 8250_fintek driver is unloaded (modprobe doesn't know that 8250_pnp rather than 8250_fintek claimed the resource). This patch merges the Fintek driver into 8250_base. On autoconfig_16550 the device is probed to verify if it is a FINTEK device or not. This custom probing can be disabled completely via configuration. When a Fintek device is not probed it will behave as a standard 16550A device, with no RS485 capabilities. Reported-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>