RK3288如何增加雙屏異顯 eDP+LVDS

這期內容當中小編將會給大家帶來有關RK3288如何增加雙屏異顯 eDP+LVDS，文章內容豐富且以專業的角度為大家分析和敘述，閱讀完這篇文章希望大家可以有所收獲。

CPU：RK3288

系統：Android 5.1

下面是官方文檔中的信息。

1、rk3288 支持的顯示接口可以任意組合。

2、雙屏異顯時，一個顯示接口當主屏，另一個當副屏；主副屏由板級 dts 文件確定，啟動后無法動態更改。

3、當兩路顯示接口顯示不同分辨率時，rk3288 只能為一路顯示接口提供精確時鐘，另一路顯示接口時鐘會有微小頻偏。

瑞芯微雖然提供了 Android 5.1 的補丁，但是本人在移植過程中出現一些問題（打補丁最好一行行核對，不要圖方便直接使用指令）。

設備 eDP 為主屏，lvds 為副屏。

（1）首先修改兩個屏參文件 lcd-xxx.dtsi。

eDP 屏參文件補丁

diff --git a/kernel/arch/arm/boot/dts/lcd-NV116FH1.dtsi b/kernel/arch/arm/boot/dts/lcd-NV116FH1.dtsi

index 3862b05..7bf992f 100755

--- a/kernel/arch/arm/boot/dts/lcd-NV116FH1.dtsi

+++ b/kernel/arch/arm/boot/dts/lcd-NV116FH1.dtsi

@@ -3,11 +3,9 @@

  *

  */

-/ {

-

-        disp_timings: display-timings {

-                        native-mode = <&timing0>;

-                        timing0: timing0 {

+        display-timings {

+                        native-mode = <&nv116fhm>;

+                        nv116fhm: timing0 {

                 screen-type = <SCREEN_EDP>;

                 out-face    = <OUT_P666>;

                 clock-frequency = <205000000>;

@@ -30,4 +30,3 @@

                swap-gb = <0>;

                         };

               };

-};

lvds 屏參文件補丁

diff --git a/kernel/arch/arm/boot/dts/lcd-ZJ080NA-08A.dtsi b/kernel/arch/arm/boot/dts/lcd-ZJ080NA-08A.dtsi

old mode 100644

new mode 100755

index fc6385c..58f999be

--- a/kernel/arch/arm/boot/dts/lcd-ZJ080NA-08A.dtsi

+++ b/kernel/arch/arm/boot/dts/lcd-ZJ080NA-08A.dtsi

@@ -3,11 +3,10 @@

  *

  */

-/ {

-        disp_timings: display-timings {

-                        native-mode = <&timing0>;

-                        timing0: timing0 {

+        display-timings {

+                        native-mode = <&zj080na>;

+                        zj080na: timing0 {

                 screen-type = <SCREEN_DUAL_LVDS>;

                 lvds-format = <LVDS_8BIT_1>;

                 out-face    = <OUT_P888>;

@@ -30,4 +30,3 @@

                swap-gb = <0>;

             };

         };

-};

（2）根據官方提供，打上 kernel 補丁

 kernel 補丁

（3）根據官方提供，打上 hardware 補丁

 hardware 補丁

（4）根據官方提供，打上 framework 補丁

 framework 補丁

（5）官方提供的補丁打完了，但是此時編譯可能會報錯，如下：

cts/tests/tests/view/src/android/view/cts/WindowTest.java:846: error: WindowTest.MockWindow is not abstract and does not override abstract method moveExtendDisplay() in Window

public class MockWindow extends Window {

^

Note: Some input files use or override a deprecated API.

Note: Recompile with -Xlint:deprecation for details.

1 error

make: *** [out/target/common/obj/APPS/CtsViewTestCases_intermediates/classes-full-debug.jar] Error 41

make: *** Waiting for unfinished jobs....

Note: Some input files use or override a deprecated API.

Note: Recompile with -Xlint:deprecation for details.

Note: Some input files use unchecked or unsafe operations.

Note: Recompile with -Xlint:unchecked for details.

Note: Some input files use or override a deprecated API.

Note: Recompile with -Xlint:deprecation for details.

Note: Some input files use unchecked or unsafe operations.

Note: Recompile with -Xlint:unchecked for details.

Warning: AndroidManifest.xml already defines minSdkVersion (in http://schemas.android.com/apk/res/android); using existing value in manifest.

Warning: AndroidManifest.xml already defines targetSdkVersion (in http://schemas.android.com/apk/res/android); using existing value in manifest.

#### make failed to build some targets (03:55 (mm:ss)) ####

根據編譯錯誤提示，需要修改 cts/tests/tests/view/src/android/view/cts/WindowTest.java 文件。

diff --git a/cts/tests/tests/view/src/android/view/cts/WindowTest.java b/cts/tests/tests/view/src/android/view/cts/WindowTest.java

index 3c5386d..8732ae7 100755

--- a/cts/tests/tests/view/src/android/view/cts/WindowTest.java

+++ b/cts/tests/tests/view/src/android/view/cts/WindowTest.java

@@ -998,6 +998,19 @@ public class WindowTest extends ActivityInstrumentationTestCase2<WindowCtsActivi

         }

         @Override

+        public void moveAppToDisplay(int id) {

+        }

+

+        @Override

+        public void syncDualDisplay() {

+        }

+

+        @Override

+        public void moveExtendDisplay() {

+        }

+

+

+        @Override

         public void setDefaultWindowFormat(int format) {

             super.setDefaultWindowFormat(format);

         }

（6）此時可以編譯成功，在屏參正確的前提下，主屏顯示正常，副屏出現花屏，需要在 system.prop 里添加屬性 ro.htg.force=1。

diff --git a/device/rockchip/rk3288/system.prop b/device/rockchip/rk3288/system.prop

index 26a2b09..c4f2c3d 100755

--- a/device/rockchip/rk3288/system.prop

+++ b/device/rockchip/rk3288/system.prop

@@ -12,6 +12,7 @@ rild.libpath=/system/lib/libril-rk29-dataonly.so

 rild.libargs=-d /dev/ttyACM0

 persist.tegra.nvmmlite = 1

 ro.audio.monitorOrientation=true

+ro.htg.force=1

 #NFC

 debug.nfc.fw_download=false

此時大功告成，雙屏可以正常顯示，也可以實現雙屏異顯。

如果 lcd 出現重復性黑屏亮屏，找到對應的屏參文件，在正常范圍內調節頻率 clk 值即可。

display-timings {

                        native-mode = <&ee101ia>;

                        ee101ia: timing0 {

                screen-type = <SCREEN_DUAL_LVDS>;

                lvds-format = <LVDS_8BIT_1>;

                out-face    = <OUT_P888>;

                color-mode = <COLOR_RGB>;

                // 調節 lcd 頻率

                clock-frequency = <148500000>;

                hactive = <1920>;

                vactive = <1080>;

如果單屏調試都正常點亮，打補丁后，點不亮或者有花屏現象，嘗試增大對應屏的電源使能延時 

 lcd_en {

    rockchip,power_type = <GPIO>;

    gpios = <&gpio7 GPIO_A5 GPIO_ACTIVE_HIGH>;

-   rockchip,delay = <10>;

+   rockchip,delay = <100>;

};

上述就是小編為大家分享的RK3288如何增加雙屏異顯 eDP+LVDS了，如果剛好有類似的疑惑，不妨參照上述分析進行理解。如果想知道更多相關知識，歡迎關注億速云行業資訊頻道。