From 1b2fe50f3dd6d808fffc707428b39329a15d5752 Mon Sep 17 00:00:00 2001 From: Bertrik Sikken Date: Sat, 1 Aug 2009 18:28:25 +0000 Subject: Meizu: update backlight brightness curve so backlight is still on at the minimum brightness setting git-svn-id: svn://svn.rockbox.org/rockbox/trunk@22102 a1c6a512-1295-4272-9138-f99709370657 --- firmware/target/arm/s5l8700/backlight-meizu.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) (limited to 'firmware/target/arm/s5l8700') diff --git a/firmware/target/arm/s5l8700/backlight-meizu.c b/firmware/target/arm/s5l8700/backlight-meizu.c index bc0c290e05..4eb6967b94 100644 --- a/firmware/target/arm/s5l8700/backlight-meizu.c +++ b/firmware/target/arm/s5l8700/backlight-meizu.c @@ -34,29 +34,30 @@ void _backlight_set_brightness(int brightness) { - /* pwm = (sqrt(2)**x)-1, where brightness level x = 0..16 */ - static const unsigned char logtable[] = - {0, 1, 2, 3, 5, 7, 10, 15, 22, 31, 44, 63, 90, 127, 180, 255}; + /* pwm = round(sqrt(2)**x), where brightness level x = 1..16 */ + static const unsigned int logtable[] = + {1, 2, 3, 4, 6, 8, 11, 16, 23, 32, 45, 64, 91, 128, 181, 256}; /* set PWM width */ - TCDATA0 = 255 - logtable[brightness]; + TCDATA0 = logtable[brightness]; } void _backlight_on(void) { + /* configure backlight pin P0.2 as timer PWM output */ + PCON0 = ((PCON0 & ~(3 << 4)) | (2 << 4)); _backlight_set_brightness(backlight_brightness); } void _backlight_off(void) { - _backlight_set_brightness(MIN_BRIGHTNESS_SETTING); + /* configure backlight pin P0.2 as GPIO and switch off */ + PCON0 = ((PCON0 & ~(3 << 4)) | (1 << 4)); + PDAT0 &= ~(1 << 2); } bool _backlight_init(void) { - /* enable backlight pin as timer output */ - PCON0 = ((PCON0 & ~(3 << 4)) | (2 << 4)); - /* enable timer clock */ PWRCON &= ~(1 << 4); @@ -64,11 +65,11 @@ bool _backlight_init(void) TCCMD = (1 << 1); /* TC_CLR */ TCCON = (0 << 13) | /* TC_INT1_EN */ (0 << 12) | /* TC_INT0_EN */ - (0 << 11) | /* TC_START */ + (1 << 11) | /* TC_START */ (3 << 8) | /* TC_CS = PCLK / 64 */ (1 << 4); /* TC_MODE_SEL = PWM mode */ - TCDATA1 = 255; /* set PWM period */ - TCPRE = 30; /* prescaler */ + TCDATA1 = 256; /* set PWM period */ + TCPRE = 20; /* prescaler */ TCCMD = (1 << 0); /* TC_EN */ _backlight_on(); -- cgit v1.2.3