[PATCH tty-next v4 0/6] convert 8250 to nbcon

John Ogness john.ogness at linutronix.de
Fri Dec 27 14:45:16 PST 2024


This is v4 of a series to convert the 8250 driver to an NBCON
console, providing both threaded and atomic printing
implementations. v3 of this series is here [0]. Additional
background information about NBCON consoles in general is
available in the cover letter of v2 [1].

The changes since v3:

- For callbacks ->rs485_stop_tx() and ->rs485_start_tx(),
  rename argument @in_con to @toggle_ier (inverts meaning).

- For univ8250_console_device_lock() and
  univ8250_console_device_unlock(), rename argument @con to @co.

- Do not introduce helpers __serial8250_stop_rx_mask_dr(),
  __serial8250_stop_rx_int(), __serial8250_start_rx_int().

- Use @frame_time to determine per-character timeout, fallback
  to 10ms if @frame_time not available.

- Use shorter code syntax when setting @console_line_ended.

- Introduce helper function fifo_wait_for_lsr() to wait for
  multiple characters.

- For serial8250_console_fifo_write() and
  serial8250_console_byte_write(), remove unnecessary
  READ_ONCE() usage.

- For serial8250_console_fifo_write() and
  serial8250_console_byte_write(), use nbcon_can_proceed()
  rather than repeatedly enter/exit unsafe regions.

- Initialize @modem_status_work using init_irq_work() rather
  than IRQ_WORK_INIT().

- Commit message and comment style cleanups as requested.

John Ogness

[0] https://lore.kernel.org/lkml/20241025105728.602310-1-john.ogness@linutronix.de
[1] https://lore.kernel.org/lkml/20240913140538.221708-1-john.ogness@linutronix.de

John Ogness (6):
  serial: 8250: Adjust the timeout for FIFO mode
  serial: 8250: Use frame rate to determine timeout
  serial: 8250: Use high-level writing function for FIFO
  serial: 8250: Provide flag for IER toggling for RS485
  serial: 8250: Switch to nbcon console
  serial: 8250: Revert "drop lockdep annotation from
    serial8250_clear_IER()"

 drivers/tty/serial/8250/8250.h            |   4 +-
 drivers/tty/serial/8250/8250_bcm2835aux.c |   4 +-
 drivers/tty/serial/8250/8250_core.c       |  35 +++-
 drivers/tty/serial/8250/8250_omap.c       |   2 +-
 drivers/tty/serial/8250/8250_port.c       | 223 +++++++++++++++++-----
 include/linux/serial_8250.h               |  12 +-
 6 files changed, 214 insertions(+), 66 deletions(-)


base-commit: 2c1fd53af21b8cb13878b054894d33d3383eb1f3
-- 
2.39.5




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