Re: [PATCH 0/3] Handle UART without interrupt on TEMT using em485

From: Giulio Benetti
Date: Thu Jan 28 2021 - 19:13:24 EST


Hi Eric,

> Il giorno 29 gen 2021, alle ore 00:37, Eric Tremblay <etremblay@xxxxxxxxxxxxxxxxxxxx> ha scritto:
>
> The series is mainly about the support of 8250 UART without TEMT
> interrupt. I saw that there was some development in the past but
> it was never merged. Since the last discussion were quite some
> time ago, I was not sure if I should post a v4 over the
> last v3 or start from scratch so I decided to post a new patch. Please
> advice if I should have done the reverse.

Please keep my and Heiko’s SoB and add your SoB too describing between [ ] what Heiko has done and what you’ve done.
For example:
SoB: Giulio
SoB: Heiko
[Heiko: ...]
SoB Eric
[Eric: improved timeout etc.]

>
> The approach is a little different from the last proposed patch which was
> doing using a polling at 100us. I tought that it could be really long on
> some fast baudrate and really not that long on slow baudrate. The current
> approach is to calculate the time of a bytes when the settings are changed.
> When we get the interrupt for the empty FIFO, it's the longer it can take
> to empty the shift register.

Good idea.

>
> The other two patches are to use that features with the PORT_16550A_FSL64
> found on some chip like the LS1043A.

Do you mind to add my 8250_dw patch that was originally part of this patchset? I had to send it
soon, you’ve preceded me :-)

Thank you
Best regards
Giulio

>
> Thanks
>
> Eric Tremblay (3):
> serial: 8250: Handle UART without interrupt on TEMT using em485
> serial: 8250: add compatible for fsl,16550-FIFO64
> serial: 8250: remove UART_CAP_TEMT on PORT_16550A_FSL64
>
> drivers/tty/serial/8250/8250.h | 1 +
> drivers/tty/serial/8250/8250_bcm2835aux.c | 2 +-
> drivers/tty/serial/8250/8250_of.c | 5 ++
> drivers/tty/serial/8250/8250_omap.c | 2 +-
> drivers/tty/serial/8250/8250_port.c | 89 ++++++++++++++++++++++-
> include/linux/serial_8250.h | 2 +
> 6 files changed, 98 insertions(+), 3 deletions(-)
>
> --
> 2.17.1