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atmel_lcdfb: Use proper blanking on negative contrast polarity 

If used with negative polarity the PWM unit cannot be disabled. This would
result in a full contrast screen.
Instead let the PWM unit enabled using 0x0 as compare value which darkens
the display.
In result no power saving is possible if inverted contrast polarity
is used.

Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
This commit is contained in:
Alexander Stein 2011-10-05 09:59:58 +02:00 committed by Florian Tobias Schandinat
parent 5d910426a6
commit acfdc2e1bd
1 changed files with 4 additions and 1 deletions
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5
drivers/video/atmel_lcdfb.c
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@ -99,8 +99,11 @@ static int atmel_bl_update_status(struct backlight_device *bl)
brightness = 0;
lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_VAL, brightness);
lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR,
if (contrast_ctr & ATMEL_LCDC_POL_POSITIVE)
lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR,
brightness ? contrast_ctr : 0);
else
lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, contrast_ctr);
bl->props.fb_blank = bl->props.power = sinfo->bl_power = power;