linux-serial.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>
To: Jacek Anaszewski <jacek.anaszewski@gmail.com>,
	Pavel Machek <pavel@ucw.cz>, Dan Murphy <dmurphy@ti.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Jiri Slaby <jslaby@suse.com>
Cc: linux-serial@vger.kernel.org, linux-leds@vger.kernel.org,
	linux-kernel@vger.kernel.org, kernel@pengutronix.de,
	Johan Hovold <johan@kernel.org>
Subject: [PATCH v10 2/3] tty: new helper function tty_get_icount()
Date: Fri, 18 Dec 2020 11:42:45 +0100	[thread overview]
Message-ID: <20201218104246.591315-3-u.kleine-koenig@pengutronix.de> (raw)
In-Reply-To: <20201218104246.591315-1-u.kleine-koenig@pengutronix.de>

For a given struct tty_struct this yields the corresponding statistics
about sent and received characters (and some more) which is needed to
implement an LED trigger for tty devices.

The new function is then used to simplify tty_tiocgicount().

Reviewed-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
---
 drivers/tty/tty_io.c | 29 +++++++++++++++++++++++++----
 include/linux/tty.h  |  2 ++
 2 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index d0c1f97adc17..61b179f2ae42 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -2486,15 +2486,36 @@ static int tty_tiocmset(struct tty_struct *tty, unsigned int cmd,
 	return tty->ops->tiocmset(tty, set, clear);
 }
 
+/**
+ *	tty_get_icount		-	get tty statistics
+ *	@tty: tty device
+ *	@icount: output parameter
+ *
+ *	Gets a copy of the tty's icount statistics.
+ *
+ *	Locking: none (up to the driver)
+ */
+int tty_get_icount(struct tty_struct *tty,
+		   struct serial_icounter_struct *icount)
+{
+	memset(icount, 0, sizeof(*icount));
+
+	if (tty->ops->get_icount)
+		return tty->ops->get_icount(tty, icount);
+	else
+		return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(tty_get_icount);
+
 static int tty_tiocgicount(struct tty_struct *tty, void __user *arg)
 {
-	int retval = -EINVAL;
 	struct serial_icounter_struct icount;
-	memset(&icount, 0, sizeof(icount));
-	if (tty->ops->get_icount)
-		retval = tty->ops->get_icount(tty, &icount);
+	int retval;
+
+	retval = tty_get_icount(tty, &icount);
 	if (retval != 0)
 		return retval;
+
 	if (copy_to_user(arg, &icount, sizeof(icount)))
 		return -EFAULT;
 	return 0;
diff --git a/include/linux/tty.h b/include/linux/tty.h
index 7c3b5f156f03..3c689e9cd494 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -501,6 +501,8 @@ extern void tty_unthrottle(struct tty_struct *tty);
 extern int tty_throttle_safe(struct tty_struct *tty);
 extern int tty_unthrottle_safe(struct tty_struct *tty);
 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
+extern int tty_get_icount(struct tty_struct *tty,
+			  struct serial_icounter_struct *icount);
 extern int is_current_pgrp_orphaned(void);
 extern void tty_hangup(struct tty_struct *tty);
 extern void tty_vhangup(struct tty_struct *tty);
-- 
2.29.2


  parent reply	other threads:[~2020-12-18 10:44 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-18 10:42 [PATCH v10 0/3] leds: trigger: implement a tty trigger Uwe Kleine-König
2020-12-18 10:42 ` [PATCH v10 1/3] tty: rename tty_kopen() and add new function tty_kopen_shared() Uwe Kleine-König
2020-12-18 10:42 ` Uwe Kleine-König [this message]
2020-12-18 10:42 ` [PATCH v10 3/3] leds: trigger: implement a tty trigger Uwe Kleine-König
2021-01-13 16:16   ` Greg Kroah-Hartman
2021-01-13 17:30     ` [PATCH v11] " Uwe Kleine-König
2021-01-13 18:34       ` Greg Kroah-Hartman
2021-02-18 13:33         ` Pavel Machek
2021-02-18 21:19           ` Uwe Kleine-König
2021-02-18 21:21             ` Greg Kroah-Hartman
2021-02-18 13:37       ` Pavel Machek
2021-02-19  8:00         ` Uwe Kleine-König
2020-12-28 15:10 ` [PATCH v10 0/3] " Greg Kroah-Hartman

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=20201218104246.591315-3-u.kleine-koenig@pengutronix.de \
    --to=u.kleine-koenig@pengutronix.de \
    --cc=dmurphy@ti.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=jacek.anaszewski@gmail.com \
    --cc=johan@kernel.org \
    --cc=jslaby@suse.com \
    --cc=kernel@pengutronix.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-leds@vger.kernel.org \
    --cc=linux-serial@vger.kernel.org \
    --cc=pavel@ucw.cz \
    /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).