linux-serial.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Eduardo Valentin <edubezval@gmail.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Jiri Slaby <jslaby@suse.com>, Fabio Estevam <festevam@gmail.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>,
	Linux PM <linux-pm@vger.kernel.org>,
	linux-serial@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>,
	Eduardo Valentin <edubezval@gmail.com>
Subject: [PATCHv2 1/8] serial: imx: remove unbalanced clk_prepare
Date: Mon, 10 Aug 2015 18:35:42 -0700	[thread overview]
Message-ID: <1439256949-626-2-git-send-email-edubezval@gmail.com> (raw)
In-Reply-To: <1439256949-626-1-git-send-email-edubezval@gmail.com>

The current code attempts to prepare clk_per and clk_ipg
before using the device. However, the result is an extra
prepare call on each clock. Here is the output of uart
clocks (only uart enabled and used as console):

$  grep uart /sys/kernel/debug/clk/clk_summary
 uart_serial           1            2    80000000          0 0
       uart           1            2    66000000          0 0

This patch balances the calls of prepares. The result is:

$  grep uart /sys/kernel/debug/clk/clk_summary
 uart_serial           1            1    80000000          0 0
       uart           1            1    66000000          0 0

Cc: Fabio Estevam <festevam@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: linux-serial@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
---
 drivers/tty/serial/imx.c | 20 ++++++--------------
 1 file changed, 6 insertions(+), 14 deletions(-)

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 9a248eb..b27c232 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -1630,12 +1630,12 @@ imx_console_write(struct console *co, const char *s, unsigned int count)
 	int locked = 1;
 	int retval;
 
-	retval = clk_enable(sport->clk_per);
+	retval = clk_prepare_enable(sport->clk_per);
 	if (retval)
 		return;
-	retval = clk_enable(sport->clk_ipg);
+	retval = clk_prepare_enable(sport->clk_ipg);
 	if (retval) {
-		clk_disable(sport->clk_per);
+		clk_disable_unprepare(sport->clk_per);
 		return;
 	}
 
@@ -1674,8 +1674,8 @@ imx_console_write(struct console *co, const char *s, unsigned int count)
 	if (locked)
 		spin_unlock_irqrestore(&sport->port.lock, flags);
 
-	clk_disable(sport->clk_ipg);
-	clk_disable(sport->clk_per);
+	clk_disable_unprepare(sport->clk_ipg);
+	clk_disable_unprepare(sport->clk_per);
 }
 
 /*
@@ -1776,15 +1776,7 @@ imx_console_setup(struct console *co, char *options)
 
 	retval = uart_set_options(&sport->port, co, baud, parity, bits, flow);
 
-	clk_disable(sport->clk_ipg);
-	if (retval) {
-		clk_unprepare(sport->clk_ipg);
-		goto error_console;
-	}
-
-	retval = clk_prepare(sport->clk_per);
-	if (retval)
-		clk_disable_unprepare(sport->clk_ipg);
+	clk_disable_unprepare(sport->clk_ipg);
 
 error_console:
 	return retval;
-- 
2.5.0

  reply	other threads:[~2015-08-11  1:35 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-08-11  1:35 [PATCHv2 0/8] serial: imx: rework pm support and add runtime pm Eduardo Valentin
2015-08-11  1:35 ` Eduardo Valentin [this message]
2015-08-11  1:35 ` [PATCHv2 2/8] serial: imx: introduce serial_imx_enable_wakeup() Eduardo Valentin
2015-08-11  1:35 ` [PATCHv2 3/8] serial: imx: allow waking up on RTSD Eduardo Valentin
2015-08-11  1:35 ` [PATCHv2 4/8] serial: imx: save and restore context in the suspend path Eduardo Valentin
2015-08-11  1:35 ` [PATCHv2 5/8] serial: imx: add a flag to indicate we are " Eduardo Valentin
2015-08-11  1:35 ` [PATCHv2 6/8] serial: imx: add runtime pm support Eduardo Valentin
2015-08-11  3:02   ` Fabio Estevam
2015-08-11 16:51     ` Eduardo Valentin
2015-08-12 19:32   ` Kevin Hilman
2015-08-11  1:35 ` [PATCHv2 7/8] serial: imx: add pm_qos request Eduardo Valentin
2015-08-11  1:35 ` [PATCHv2 8/8] serial: imx: use SET_*SYSTEM_PM_OPS helper functions Eduardo Valentin

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=1439256949-626-2-git-send-email-edubezval@gmail.com \
    --to=edubezval@gmail.com \
    --cc=festevam@gmail.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=jslaby@suse.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=linux-serial@vger.kernel.org \
    --cc=s.hauer@pengutronix.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;
as well as URLs for NNTP newsgroup(s).