Re: [PATCH v5 00/14] serial: 8250: add Moxa MUEx50 PCIe board support

Greg Kroah-Hartman <[email protected]> Mon, 3 Aug 2026 16:52:57 +0200
Newsgroups org.kernel.vger.linux-serial,org.kernel.vger.linux-kernel
Message-ID <2026080335-prewashed-cozily-9bc8@gregkh>
On Fri, Jul 31, 2026 at 03:48:06PM +0800, Crescent Hsieh wrote:
> This series consolidates Moxa PCIe multiport serial board support under a
> dedicated 8250_mxpcie driver and adds MUEx50 UART support needed by these
> boards.
> 
> The first part splits the existing Moxa PCIe board handling out of
> 8250_pci into a separate driver while preserving the existing probe flow
> and device IDs. The series then introduces the MUEx50 UART port type and
> enables the board-specific UART setup, including enhanced mode and FIFO
> trigger programming.
> 
> The driver adds hardware-assisted flow control support for MUEx50 UARTs,
> including automatic RTS/CTS handling and XON/XOFF offload. It also adds a
> custom IRQ path and uses the MUEx50 memory-mapped FIFO windows to improve
> RX and TX data movement.
> 
> Later patches add serial interface mode switching, RS485 break handling,
> and per-port private state for MUEx50-specific configuration. The driver
> supports switching the serial interface mode through the RS485
> configuration path, covering RS232, RS422, and RS485 modes supported by
> the boards.
> 
> The final part extends 8250 core callbacks where needed so low-level
> drivers can override break control and rx_trig_bytes handling. The
> 8250_mxpcie driver uses these hooks to implement RS485 break handling via
> MUEx50 features and to expose the MUEx50 programmable RX trigger level
> through the generic rx_trig_bytes sysfs interface.

I've queued this up now, for the issues that Andy pointed out, feel free
to just send follow-on patches, thanks!

greg k-h