[PATCH v4 09/26] ARM: pxa: magician: Optimize powerup delays for Samsung LCD
From: Petr Cvek
Date: Mon Sep 28 2015 - 17:16:19 EST
Delays for the Samsung LCD are greater than needed. These values were
extracted from a datasheet.
Signed-off-by: Petr Cvek <petr.cvek@xxxxxx>
---
arch/arm/mach-pxa/magician.c | 14 ++++++--------
1 file changed, 6 insertions(+), 8 deletions(-)
diff --git a/arch/arm/mach-pxa/magician.c b/arch/arm/mach-pxa/magician.c
index d78fc3a..14d1f55 100644
--- a/arch/arm/mach-pxa/magician.c
+++ b/arch/arm/mach-pxa/magician.c
@@ -366,21 +366,19 @@ static void samsung_lcd_power(int on, struct fb_var_screeninfo *si)
gpio_set_value(GPIO75_MAGICIAN_SAMSUNG_POWER, 1);
else
gpio_set_value(EGPIO_MAGICIAN_LCD_POWER, 1);
- mdelay(10);
+ mdelay(6);
gpio_set_value(GPIO106_MAGICIAN_LCD_DCDC_NRESET, 1);
- mdelay(10);
+ mdelay(6); /* Avdd -> Voff >5ms */
gpio_set_value(GPIO104_MAGICIAN_LCD_VOFF_EN, 1);
- mdelay(30);
+ mdelay(16); /* Voff -> Von >(5+10)ms */
gpio_set_value(GPIO105_MAGICIAN_LCD_VON_EN, 1);
- mdelay(10);
} else {
- mdelay(10);
gpio_set_value(GPIO105_MAGICIAN_LCD_VON_EN, 0);
- mdelay(30);
+ mdelay(16);
gpio_set_value(GPIO104_MAGICIAN_LCD_VOFF_EN, 0);
- mdelay(10);
+ mdelay(6);
gpio_set_value(GPIO106_MAGICIAN_LCD_DCDC_NRESET, 0);
- mdelay(10);
+ mdelay(6);
if (system_rev < 3)
gpio_set_value(GPIO75_MAGICIAN_SAMSUNG_POWER, 0);
else
--
1.7.12.1
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