From 642c1f519a693989f07d1c43f50bd47bafb53422 Mon Sep 17 00:00:00 2001 From: Lukasz Majewski Date: Sun, 20 May 2018 08:33:14 +0200 Subject: [PATCH] board: imx53: Always disable display before starting kernel This patch prevents from the situation where we may end up with garbage displayed on the LCD panel. Such situation occurs when one performs "reboot -f" in Linux and then stop in U-boot (or observe the garbage on the screen during boot up). To prevent from such situation - the PWM pin is configured as GPIO and set to LOW. Signed-off-by: Lukasz Majewski --- arch/arm/dts/imx53-kp.dts | 2 ++ board/k+p/kp_imx53/kp_imx53.c | 8 ++++++++ 2 files changed, 10 insertions(+) diff --git a/arch/arm/dts/imx53-kp.dts b/arch/arm/dts/imx53-kp.dts index fd64a9f2f6..6322ef1323 100644 --- a/arch/arm/dts/imx53-kp.dts +++ b/arch/arm/dts/imx53-kp.dts @@ -86,6 +86,8 @@ MX53_PAD_PATA_DA_2__GPIO7_8 0x1e4 /* BOOSTER_OFF */ MX53_PAD_EIM_CS0__GPIO2_23 0x1e4 + /* LCD BACKLIGHT */ + MX53_PAD_GPIO_1__GPIO1_1 0x1e4 >; }; diff --git a/board/k+p/kp_imx53/kp_imx53.c b/board/k+p/kp_imx53/kp_imx53.c index c80eed36c6..6b0db6b8de 100644 --- a/board/k+p/kp_imx53/kp_imx53.c +++ b/board/k+p/kp_imx53/kp_imx53.c @@ -22,6 +22,7 @@ #define VBUS_PWR_EN IMX_GPIO_NR(7, 8) #define PHY_nRST IMX_GPIO_NR(7, 6) #define BOOSTER_OFF IMX_GPIO_NR(2, 23) +#define LCD_BACKLIGHT IMX_GPIO_NR(1, 1) DECLARE_GLOBAL_DATA_PTR; @@ -189,10 +190,17 @@ void eth_phy_reset(void) udelay(50); } +void board_disable_display(void) +{ + gpio_request(LCD_BACKLIGHT, "LCD_BACKLIGHT"); + gpio_direction_output(LCD_BACKLIGHT, 0); +} + int board_late_init(void) { int ret = 0; + board_disable_display(); setup_ups(); if (!power_init()) -- 2.39.5