linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: Jisheng.Zhang@synaptics.com (Jisheng Zhang)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v2 2/3] serial: 8250: introduce get_divisor() and set_divisor() hook
Date: Wed, 4 Jul 2018 17:02:17 +0800	[thread overview]
Message-ID: <20180704170217.190711ef@xhacker.debian> (raw)
In-Reply-To: <20180704165908.4bb8b090@xhacker.debian>

Add these two hooks so that they can be overridden with driver specific
implementations.

Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
---
 drivers/tty/serial/8250/8250_core.c |  4 ++++
 drivers/tty/serial/8250/8250_port.c | 27 +++++++++++++++++++++++----
 include/linux/serial_core.h         |  7 +++++++
 3 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 9342fc2ee7df..a0bb77290747 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -1023,6 +1023,10 @@ int serial8250_register_8250_port(struct uart_8250_port *up)
 			uart->port.get_mctrl = up->port.get_mctrl;
 		if (up->port.set_mctrl)
 			uart->port.set_mctrl = up->port.set_mctrl;
+		if (up->port.get_divisor)
+			uart->port.get_divisor = up->port.get_divisor;
+		if (up->port.set_divisor)
+			uart->port.set_divisor = up->port.set_divisor;
 		if (up->port.startup)
 			uart->port.startup = up->port.startup;
 		if (up->port.shutdown)
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 709fe6b4265c..ce0dc17f18ee 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2498,9 +2498,9 @@ static unsigned int npcm_get_divisor(struct uart_8250_port *up,
 	return DIV_ROUND_CLOSEST(port->uartclk, 16 * baud + 2) - 2;
 }
 
-static unsigned int serial8250_get_divisor(struct uart_port *port,
-					   unsigned int baud,
-					   unsigned int *frac)
+static unsigned int serial8250_do_get_divisor(struct uart_port *port,
+					      unsigned int baud,
+					      unsigned int *frac)
 {
 	struct uart_8250_port *up = up_to_u8250p(port);
 	unsigned int quot;
@@ -2532,6 +2532,16 @@ static unsigned int serial8250_get_divisor(struct uart_port *port,
 	return quot;
 }
 
+static unsigned int serial8250_get_divisor(struct uart_port *port,
+					   unsigned int baud,
+					   unsigned int *frac)
+{
+	if (port->get_divisor)
+		return port->get_divisor(port, baud, frac);
+
+	return serial8250_do_get_divisor(port, baud, frac);
+}
+
 static unsigned char serial8250_compute_lcr(struct uart_8250_port *up,
 					    tcflag_t c_cflag)
 {
@@ -2570,7 +2580,7 @@ static unsigned char serial8250_compute_lcr(struct uart_8250_port *up,
 	return cval;
 }
 
-static void serial8250_set_divisor(struct uart_port *port, unsigned int baud,
+static void serial8250_do_set_divisor(struct uart_port *port, unsigned int baud,
 			    unsigned int quot, unsigned int quot_frac)
 {
 	struct uart_8250_port *up = up_to_u8250p(port);
@@ -2603,6 +2613,15 @@ static void serial8250_set_divisor(struct uart_port *port, unsigned int baud,
 	}
 }
 
+static void serial8250_set_divisor(struct uart_port *port, unsigned int baud,
+				   unsigned int quot, unsigned int quot_frac)
+{
+	if (port->set_divisor)
+		port->set_divisor(port, baud, quot, quot_frac);
+	else
+		serial8250_do_set_divisor(port, baud, quot, quot_frac);
+}
+
 static unsigned int serial8250_get_baud_rate(struct uart_port *port,
 					     struct ktermios *termios,
 					     struct ktermios *old)
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 06ea4eeb09ab..406edae44ca3 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -127,6 +127,13 @@ struct uart_port {
 					     struct ktermios *);
 	unsigned int		(*get_mctrl)(struct uart_port *);
 	void			(*set_mctrl)(struct uart_port *, unsigned int);
+	unsigned int		(*get_divisor)(struct uart_port *,
+					       unsigned int baud,
+					       unsigned int *frac);
+	void			(*set_divisor)(struct uart_port *,
+					       unsigned int baud,
+					       unsigned int quot,
+					       unsigned int quot_frac);
 	int			(*startup)(struct uart_port *port);
 	void			(*shutdown)(struct uart_port *port);
 	void			(*throttle)(struct uart_port *port);
-- 
2.18.0

  parent reply	other threads:[~2018-07-04  9:02 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-07-04  8:59 [PATCH v2 0/3] serial: 8250_dw: add fractional divisor support Jisheng Zhang
2018-07-04  9:00 ` [PATCH v2 1/3] serial: 8250: let serial8250_get_divisor() get uart_port * as param Jisheng Zhang
2018-07-04 10:00   ` Andy Shevchenko
2018-07-04  9:02 ` Jisheng Zhang [this message]
2018-07-04 10:00   ` [PATCH v2 2/3] serial: 8250: introduce get_divisor() and set_divisor() hook Andy Shevchenko
2018-07-04  9:03 ` [PATCH v2 3/3] serial: 8250_dw: add fractional divisor support Jisheng Zhang
2018-07-04 16:08   ` Andy Shevchenko
2018-07-05  6:39     ` Jisheng Zhang
2018-07-05  6:54       ` Jisheng Zhang
2018-07-06 17:39         ` Andy Shevchenko
2018-07-06 17:37       ` Andy Shevchenko
2018-07-09  6:04         ` Jisheng Zhang
2018-07-09  6:15           ` Andy Shevchenko

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=20180704170217.190711ef@xhacker.debian \
    --to=jisheng.zhang@synaptics.com \
    --cc=linux-arm-kernel@lists.infradead.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).