[RFC PATCH v2 0/2] serial: imx: Switch to nbcon console

[Esben Haabendal <esben@geanix.com>]

This is a first attempt at porting another serial console driver to nbcon.

The first patch is a preparatory patch, thought to be suitable for mainline
inclusion now, while the second patch is for rt only for now.

The second patch does have quite a copy-paste feeling to it.

The imx_uart_console_write_atomic() and imx_uart_console_write_thread()
includes copies of code from the old imx_uart_console_write() function.
This is similar to current status of nbcon support in 8250 driver.

The midle part of imx_uart_console_write_thread() is identical to the
middle part of serial8250_console_write_thread() in
drivers/tty/serial/8250/8250_port.c, except for the arguments to
uart_console_write() function.

There is clearly potential for writing some common code to avoid both cases
of copy-paste code.

I am unsure about what the plan is for keeping the legacy console code in
the drivers. Are we going to drop that before submitting the code to
mainline?

v2:
- Switch to tight loop (no udelay()) in atomic context.
- Increase timeout to 1 second.
- Add note in commit message about (no) error handling on timeout.


Esben Haabendal (2):
  serial: imx: Introduce timeout when waiting on transmitter empty
  serial: imx: Switch to nbcon console

 drivers/tty/serial/imx.c | 161 ++++++++++++++++++++++++++++++++++++++-
 1 file changed, 157 insertions(+), 4 deletions(-)

-- 
2.44.0