linux-kernel - [PATCH] backlight: l4f00242t03: Prevent unbalanced calls to regulator enable/disable

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Message-ID: <1291044971.3139.61.camel@realization>
Date:	Mon, 29 Nov 2010 16:36:11 +0100
From:	Alberto Panizzo <maramaopercheseimorto@...il.com>
To:	Andrew Morton <akpm@...ux-foundation.org>
Cc:	Richard Purdie <rpurdie@...ys.net>,
	Marek Vasut <marek.vasut@...il.com>, Tejun Heo <tj@...nel.org>,
	Axel Lin <axel.lin@...il.com>,
	linux-kernel <linux-kernel@...r.kernel.org>
Subject: [PATCH] backlight: l4f00242t03: Prevent unbalanced calls to
 regulator enable/disable

Otherwise a double call to:
$ echo 4 > /sys/class/lcd/l4f00242t03/lcd_power
Will, the first power down the lcd and regulators correctly and the
second produce an unbalanced call to regulator disable.

Signed-off-by: Alberto Panizzo <maramaopercheseimorto@...il.com>
---

This patch follow the one this mail is answering.
Thanks for reviewing.

Best regards,
Alberto!

 drivers/video/backlight/l4f00242t03.c |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/video/backlight/l4f00242t03.c b/drivers/video/backlight/l4f00242t03.c
index c04aa90..98ad3e5 100644
--- a/drivers/video/backlight/l4f00242t03.c
+++ b/drivers/video/backlight/l4f00242t03.c
@@ -136,10 +136,12 @@ static int l4f00242t03_lcd_power_set(struct lcd_device *ld, int power)
 		}
 	} else {
 		/* power == FB_BLANK_POWERDOWN */
-		/* Clear the screen before shutting down */
-		spi_write(spi, (const u8 *)&disoff, sizeof(u16));
-		msleep(60);
-		l4f00242t03_lcd_powerdown(spi);
+		if (priv->lcd_state != FB_BLANK_POWERDOWN) {
+			/* Clear the screen before shutting down */
+			spi_write(spi, (const u8 *)&disoff, sizeof(u16));
+			msleep(60);
+			l4f00242t03_lcd_powerdown(spi);
+		}
 	}
 
 	priv->lcd_state = power;
-- 
1.6.3.3



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