Re: [PATCH 0/7] serial: 8250: Add rs485 emulation to 8250_dw

From: Andy Shevchenko
Date: Wed Mar 18 2020 - 11:13:19 EST


On Wed, Mar 18, 2020 at 03:26:33PM +0100, Heiko Stuebner wrote:
> This series tries to revive the work of Giulio Benetti from 2018 [0]
> which seemed to have stalled at that time.
>
> The board I needed that on also had the additional caveat that it
> uses non-standard pins for DE/RE so needed gpio mctrl layer as well
> and even more special needed to control the RE pin manually not as
> part of it being connected to the DE signal as seems to be the standard.
>
> So I've marked the patch doing this as DTR pin as RFC but that patch
> isn't needed for the other core functionality, so could also be left out.

I'm wondering if this series is based on tty-next? Can you use --base in next version to clarify this?

>
> Changes from the 2018 submission include:
> - add timeout when waiting for fifos to clear using a new helper
> - move on-boot enablement of the rs485 mode to after registering
> the port. This saves having to copy the em485 struct as done
> originally, which also ran into spinlock-debug warnings when testing
> and also makes it actually possible to use the mctrl gpio layer
> for non-standard gpios.
>
> [0] Link: https://lore.kernel.org/linux-serial/20180601124021.102970-1-giulio.benetti@xxxxxxxxxxxxxxxx/
>
> Giulio Benetti (4):
> serial: 8250: Make em485_rts_after_send() set mctrl according to rts
> state.
> serial: 8250: Handle case port doesn't have TEMT interrupt using
> em485.
> serial: 8250_dw: add em485 support
> serial: 8250_dw: allow enable rs485 at boot time
>
> Heiko Stuebner (3):
> serial: 8250: add serial_in_poll_timeout helper
> serial: 8250: Start rs485 after registering port if rs485 is enabled
> in probe
> serial: 8250: handle DTR in rs485 emulation
>
> drivers/tty/serial/8250/8250.h | 36 ++++++++++++++++++++-
> drivers/tty/serial/8250/8250_core.c | 9 ++++++
> drivers/tty/serial/8250/8250_dw.c | 35 +++++++++++++++++++-
> drivers/tty/serial/8250/8250_of.c | 2 +-
> drivers/tty/serial/8250/8250_omap.c | 2 +-
> drivers/tty/serial/8250/8250_port.c | 50 +++++++++++++++++++++++------
> include/linux/serial_8250.h | 1 +
> 7 files changed, 121 insertions(+), 14 deletions(-)
>
> --
> 2.24.1
>

--
With Best Regards,
Andy Shevchenko