Eric Lee / smarc-uboot

Download as
Browse Code ยป

Commit 642c1f519a693989f07d1c43f50bd47bafb53422

Authored by Lukasz Majewski
Committed by Stefano Babic
1 parent faab193ea2
Exists in smarc_8mq_lf_v2020.04 and in 11 other branches 8qm-imx_v2020.04_5.4.70_2.3.0, emb_lf_v2022.04, pitx_8mp_lf_v2020.04, smarc-8m-android-10.0.0_2.6.0, smarc-8m-android-11.0.0_2.0.0, smarc-8mp-android-11.0.0_2.0.0, smarc_8m-imx_v2019.04_4.19.35_1.1.0, smarc_8mm-imx_v2019.04_4.19.35_1.1.0, smarc_8mm-imx_v2020.04_5.4.24_2.1.0, smarc_8mp_lf_v2020.04, smarc_8mq-imx_v2020.04_5.4.24_2.1.0

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 <lukma@denx.de>

Showing 2 changed files with 10 additions and 0 deletions Side-by-side Diff

arch/arm/dts/imx53-kp.dts
Diff comments   View file @ 642c1f5
... ... @@ -86,6 +86,8 @@
86 86 MX53_PAD_PATA_DA_2__GPIO7_8 0x1e4
87 87 /* BOOSTER_OFF */
88 88 MX53_PAD_EIM_CS0__GPIO2_23 0x1e4
  89 + /* LCD BACKLIGHT */
  90 + MX53_PAD_GPIO_1__GPIO1_1 0x1e4
89 91 >;
90 92 };
91 93  
board/k+p/kp_imx53/kp_imx53.c
Diff comments   View file @ 642c1f5
... ... @@ -22,6 +22,7 @@
22 22 #define VBUS_PWR_EN IMX_GPIO_NR(7, 8)
23 23 #define PHY_nRST IMX_GPIO_NR(7, 6)
24 24 #define BOOSTER_OFF IMX_GPIO_NR(2, 23)
  25 +#define LCD_BACKLIGHT IMX_GPIO_NR(1, 1)
25 26  
26 27 DECLARE_GLOBAL_DATA_PTR;
27 28  
28 29  
... ... @@ -189,10 +190,17 @@
189 190 udelay(50);
190 191 }
191 192  
  193 +void board_disable_display(void)
  194 +{
  195 + gpio_request(LCD_BACKLIGHT, "LCD_BACKLIGHT");
  196 + gpio_direction_output(LCD_BACKLIGHT, 0);
  197 +}
  198 +
192 199 int board_late_init(void)
193 200 {
194 201 int ret = 0;
195 202  
  203 + board_disable_display();
196 204 setup_ups();
197 205  
198 206 if (!power_init())