serial: stm32: implement prescaler tuning to compute low baudrate

Browse source

In the case of high USART input clock and low baud rate, BRR value
is not enough to get correct baud rate. So here we use USART prescaler to
divide USART input clock to get the correct baud rate.

PRESC register is only available since stm32h7.

Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20240112095300.2004878-2-valentin.caron@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

...

This commit is contained in:

Valentin Caron 2024-01-12 10:52:57 +01:00 • committed by Greg Kroah-Hartman

parent 5c49b6a4a4

commit ec240f8893

2 changed files with 56 additions and 21 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

71

drivers/tty/serial/stm32-usart.c

View file

6

drivers/tty/serial/stm32-usart.h

View file