Pull TTY / serial driver updates from Greg KH:
 "Here is the "big" set of tty and serial driver updates for 7.3-rc1.

  Not really all that much happened this development cycle for this
  subsystem, changes in here are:

   - removal of the ipwireless driver as it's no longer used or needed

   - new 8250_mxpcie driver added

   - qcom serial driver updates and additions

   - vt mode validation addition

   - lots of other small serial driver updates and additions

  All of these have been in linux-next for weeks with no reported issues"

* tag 'tty-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (97 commits)
  serial: imx: serialize imx_uart_ports[] lifetime
  tty: clear cdev pointer after cdev_add() failure
  tty: skip cdev_del() when no cdev is registered
  serial: core: clear freed pointers on uart_register_driver() failure
  serial: core: do fallible allocations before the console can be registered
  serial: 8250_mxpcie: implement rx_trig_bytes callbacks via MUEx50 RTL
  serial: 8250_mxpcie: introduce per-port private data structure
  serial: 8250: allow UART drivers to override rx_trig_bytes handling
  serial: 8250_mxpcie: add break support for RS485 using MUEx50 features
  serial: 8250: allow low-level drivers to override break control
  serial: 8250_mxpcie: support serial interface mode switching
  serial: 8250_mxpcie: speed up TX using memory-mapped FIFO window
  serial: 8250_mxpcie: speed up RX using memory-mapped FIFO window
  serial: 8250_mxpcie: add custom handle_irq callback
  serial: 8250_mxpcie: offload XON/XOFF flow control to MUEx50 hardware
  serial: 8250_mxpcie: enable automatic RTS/CTS flow control
  serial: 8250_mxpcie: enable enhanced mode and program FIFO trigger levels
  serial: 8250: add Moxa MUEx50 UART port type
  serial: 8250: split Moxa PCIe serial board support out of 8250_pci
  serial: qcom-geni: Use geni_se_set_perf_level() for baud rate perf level
  ...

The MUEx50 UART exposes a programmable RX trigger level via the RTL
register.

Implement uart_port RX trigger set/get callbacks for the mxpcie driver
and wire them up to the generic rx_trig_bytes sysfs interface. Store the
configured trigger level in the per-port private data.

Signed-off-by: Crescent Hsieh <crescentcy.hsieh@moxa.com>
Link: https://patch.msgid.link/20260731074820.735619-15-crescentcy.hsieh@moxa.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Introduce a private per-port data structure for the mxpcie driver and
replace the shared flexible array of registered lines with an array of
per-port objects.

This prepares the driver for storing per-port state needed by subsequent
features.

No functional change intended.

Signed-off-by: Crescent Hsieh <crescentcy.hsieh@moxa.com>
Link: https://patch.msgid.link/20260731074820.735619-14-crescentcy.hsieh@moxa.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The rx_trig_bytes sysfs attribute currently relies on 8250-internal
helper functions and assumes a fixed mapping between trigger levels and
FIFO behavior.

Some UARTs provide hardware-specific RX trigger mechanisms that do not
fit this model. Add optional uart_port callbacks for setting and getting
the RX trigger level, and use them when provided, while preserving the
existing 8250 helpers as the default fallback.

Signed-off-by: Crescent Hsieh <crescentcy.hsieh@moxa.com>
Link: https://patch.msgid.link/20260731074820.735619-13-crescentcy.hsieh@moxa.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

On MUEx50, break signaling under RS485 requires a driver-specific
sequence and cannot be handled correctly by the generic 8250 break
implementation alone.

Implement a mxpcie break_ctl callback that performs MUEx50-specific
break handling when RS485 is enabled and fall back to the default 8250
break handling for other modes.

Signed-off-by: Crescent Hsieh <crescentcy.hsieh@moxa.com>
Link: https://patch.msgid.link/20260731074820.735619-12-crescentcy.hsieh@moxa.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Some UARTs require driver-specific handling for break signaling, which
cannot be expressed by the generic 8250 break implementation alone.

Add an optional uart_port break_ctl callback and route
serial8250_break_ctl() through it when provided. Rename the existing
8250 implementation to serial8250_do_break_ctl() and export it so
low-level drivers can reuse the default 8250 behavior when appropriate.

Signed-off-by: Crescent Hsieh <crescentcy.hsieh@moxa.com>
Link: https://patch.msgid.link/20260731074820.735619-11-crescentcy.hsieh@moxa.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Moxa PCIe multiport serial boards support switching the serial interface
mode between RS232, RS422, RS485-2W, and RS485-4W via on-board control
registers.

Implement an rs485_config() callback and map TIOCSRS485 requests to the
corresponding hardware modes using serial_rs485 flags:

  - RS232                  = (no flags set)
  - RS422                  = SER_RS485_ENABLED | SER_RS485_MODE_RS422
  - RS485_2W (half-duplex) = SER_RS485_ENABLED
  - RS485_4W (full-duplex) = SER_RS485_ENABLED | SER_RS485_RX_DURING_TX

This allows users to reconfigure the serial mode at runtime via ioctl().

Signed-off-by: Crescent Hsieh <crescentcy.hsieh@moxa.com>
Link: https://patch.msgid.link/20260731074820.735619-10-crescentcy.hsieh@moxa.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The MUEx50 UART provides a memory-mapped TX FIFO data window along with
a TX FIFO level counter.

Fill the TX FIFO in bulk via the MMIO FIFO window based on available
FIFO space, using uart_port_tx_limited() for the common serial-core TX
handling.

Signed-off-by: Crescent Hsieh <crescentcy.hsieh@moxa.com>
Link: https://patch.msgid.link/20260731074820.735619-9-crescentcy.hsieh@moxa.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The MUEx50 UART provides a memory-mapped RX FIFO data window along with
an RX FIFO byte counter.

When no break or error conditions are present, read received data in
bulk via the MMIO FIFO window and push it to the tty layer in one
operation. Fall back to the generic 8250 RX path for break and error
handling.

Signed-off-by: Crescent Hsieh <crescentcy.hsieh@moxa.com>
Link: https://patch.msgid.link/20260731074820.735619-8-crescentcy.hsieh@moxa.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Add a mxpcie-specific handle_irq() implementation for Moxa PCIe serial
ports.

This keeps the interrupt handling self-contained in the driver and
provides a hook point for MUEx50-specific RX/TX paths added in subsequent
patches. The handler processes RX, updates modem status, and handles TX
when THRE is asserted.

Signed-off-by: Crescent Hsieh <crescentcy.hsieh@moxa.com>
Link: https://patch.msgid.link/20260731074820.735619-7-crescentcy.hsieh@moxa.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>