From: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
To: Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Jiri Slaby <jslaby@suse.com>
Cc: linux-arm-kernel@lists.infradead.org,
linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v6 0/3] serial: 8250_dw: add fractional divisor support
Date: Thu, 12 Jul 2018 09:55:04 +0800 [thread overview]
Message-ID: <20180712095504.4d9583ce@xhacker.debian> (raw)
For Synopsys DesignWare 8250 uart which version >= 4.00a, there's a
valid divisor latch fraction register. The fractional divisor width is
4bits ~ 6bits.
patch1 introduces necessary hooks to 8250 core.
patch2 exports serial8250_do_set_divisor()
patch3 implements the fractional divisor support for Synopsys DW 8250.
Since v5:
- Add Andy's Reviewed-by tag to all patches.
Since v4:
- use tmp to save baud * 16 rather than calculate every time in
dw8250_get_divisor()
Since v3:
- simplify the dw8250_get_divisor() implementation again.
Since v2:
- rebase to tty-next branch, since I need one patch from Andy which
is in tty-next
- drop the patch "serial: 8250: let serial8250_get_divisor() get
uart_port * as param" since it's in tty-next now.
- add a new patch to export serial8250_do_set_divisor(), and reuse it
to complete dw8250_set_divisor().
- remove DW 8250 version check, since the DLF register always exists
and if fractional divisor isn't supported, the register read as 0
- add comments to explain how dw8250_get_divisor() get quot and frac.
- the frac calcuation is simplified with well implemented GENMASK
- Add Andy's Reviewed-by tag to patch1.
Since v1:
- add an extra patch to let serial8250_get_divisor() get uart_port *
as param
- take Andy's suggestions to "integrates hooks in the same way like
it's done for the rest of 8250 ones". Many thanks to Andy.
Jisheng Zhang (3):
serial: 8250: introduce get_divisor() and set_divisor() hook
serial: 8250: export serial8250_do_set_divisor()
serial: 8250_dw: add fractional divisor support
drivers/tty/serial/8250/8250_core.c | 4 +++
drivers/tty/serial/8250/8250_dw.c | 45 +++++++++++++++++++++++++++++
drivers/tty/serial/8250/8250_port.c | 30 +++++++++++++++----
include/linux/serial_8250.h | 3 ++
include/linux/serial_core.h | 7 +++++
5 files changed, 84 insertions(+), 5 deletions(-)
--
2.18.0
next reply other threads:[~2018-07-12 1:57 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-07-12 1:55 Jisheng Zhang [this message]
2018-07-12 1:57 ` [PATCH v6 1/3] serial: 8250: introduce get_divisor() and set_divisor() hook Jisheng Zhang
2018-07-12 1:58 ` [PATCH v6 2/3] serial: 8250: export serial8250_do_set_divisor() Jisheng Zhang
2018-07-12 1:59 ` [PATCH v6 3/3] serial: 8250_dw: add fractional divisor support Jisheng Zhang
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=20180712095504.4d9583ce@xhacker.debian \
--to=jisheng.zhang@synaptics.com \
--cc=andriy.shevchenko@linux.intel.com \
--cc=gregkh@linuxfoundation.org \
--cc=jslaby@suse.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-serial@vger.kernel.org \
/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;
as well as URLs for NNTP newsgroup(s).