From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: John Ogness <john.ogness@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Jiri Slaby <jirislaby@kernel.org>, Petr Mladek <pmladek@suse.com>,
Sergey Senozhatsky <senozhatsky@chromium.org>,
Steven Rostedt <rostedt@goodmis.org>,
Thomas Gleixner <tglx@linutronix.de>,
Esben Haabendal <esben@geanix.com>,
linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org,
Arnd Bergmann <arnd@arndb.de>,
Niklas Schnelle <schnelle@linux.ibm.com>,
Serge Semin <fancer.lancer@gmail.com>
Subject: Re: [PATCH tty-next v5 2/6] serial: 8250: Use frame time to determine timeout
Date: Mon, 13 Jan 2025 11:54:35 +0200 [thread overview]
Message-ID: <Z4Ti24Sw4zo5-wqe@smile.fi.intel.com> (raw)
In-Reply-To: <20250107212702.169493-3-john.ogness@linutronix.de>
On Tue, Jan 07, 2025 at 10:32:58PM +0106, John Ogness wrote:
> Rather than using a hard-coded per-character Tx-timeout of 10ms,
> use the frame time to determine a timeout value. The value is
> doubled to ensure that a timeout is only hit during unexpected
> circumstances.
>
> Since the frame time may not be available during early printing,
> the previous 10ms value is kept as a fallback.
...
> + /*
> + * Wait for a character to be sent. Fallback to a safe default
> + * timeout value if @frame_time is not available.
> + */
> + if (up->port.frame_time)
> + tmout = up->port.frame_time * 2 / NSEC_PER_USEC;
> + else
> + tmout = 10000;
I would use it in a form of
tmout = 10 * USEC_PER_MSEC;
This will give a hint of the real unit (10 ms in us).
--
With Best Regards,
Andy Shevchenko
next prev parent reply other threads:[~2025-01-13 9:54 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-01-07 21:26 [PATCH tty-next v5 0/6] convert 8250 to nbcon John Ogness
2025-01-07 21:26 ` [PATCH tty-next v5 1/6] serial: 8250: Adjust the timeout for FIFO mode John Ogness
2025-01-07 21:26 ` [PATCH tty-next v5 2/6] serial: 8250: Use frame time to determine timeout John Ogness
2025-01-13 9:54 ` Andy Shevchenko [this message]
2025-01-07 21:26 ` [PATCH tty-next v5 3/6] serial: 8250: Use high-level writing function for FIFO John Ogness
2025-01-07 21:27 ` [PATCH tty-next v5 4/6] serial: 8250: Provide flag for IER toggling for RS485 John Ogness
2025-01-07 21:27 ` [PATCH tty-next v5 5/6] serial: 8250: Switch to nbcon console John Ogness
2025-01-09 16:13 ` Petr Mladek
2025-01-15 16:21 ` Jon Hunter
2025-01-15 16:54 ` John Ogness
2025-01-16 10:27 ` Jon Hunter
2025-01-16 10:38 ` John Ogness
2025-01-16 10:41 ` Jon Hunter
2025-01-20 16:23 ` Thierry Reding
2025-01-20 16:34 ` Thierry Reding
2025-01-27 14:54 ` Jon Hunter
2025-01-27 15:20 ` Petr Mladek
2025-01-27 15:21 ` John Ogness
2025-01-27 16:13 ` Jon Hunter
2025-10-08 15:56 ` John Ogness
2025-10-08 19:21 ` Jon Hunter
2025-10-09 10:04 ` Thierry Reding
2025-10-09 11:49 ` John Ogness
2025-10-09 12:54 ` Petr Mladek
2025-01-07 21:27 ` [PATCH tty-next v5 6/6] serial: 8250: Revert "drop lockdep annotation from serial8250_clear_IER()" John Ogness
2025-01-09 16:13 ` Petr Mladek
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=Z4Ti24Sw4zo5-wqe@smile.fi.intel.com \
--to=andriy.shevchenko@linux.intel.com \
--cc=arnd@arndb.de \
--cc=esben@geanix.com \
--cc=fancer.lancer@gmail.com \
--cc=gregkh@linuxfoundation.org \
--cc=jirislaby@kernel.org \
--cc=john.ogness@linutronix.de \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-serial@vger.kernel.org \
--cc=pmladek@suse.com \
--cc=rostedt@goodmis.org \
--cc=schnelle@linux.ibm.com \
--cc=senozhatsky@chromium.org \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox