SDM660平台PWM配置

本文主要是介绍SDM660平台PWM配置，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

概述：高通sdm660平台代码默认配置为WLED，支持OLED，而我们的硬件设置为PWM，刚开始配置，我直接让跑了wled，但并没有输出，当手动拉高pwm输出，屏可以正常显示，所以就需要配置pwm，分为xbl和kernel两个阶段的配置。

1、xbl配置

根据硬件，两个控制引脚背光使能gpio76和PWM（pm660a_gpio6），首先我们需要将gpio6复用为pwm，另外，xbl采用了lpg模式控制背光（lpg=pwm），添加如下：

diff --git a/boot_images/QcomPkg/Sdm660Pkg/Library/MDPPlatformLib/MDPPlatformLib.c b/boot_images/QcomPkg/Sdm660Pkg/Library/MDPPlatformLib/MDPPlatformLib.c
index 874e14d90..221127074 100755
--- a/boot_images/QcomPkg/Sdm660Pkg/Library/MDPPlatformLib/MDPPlatformLib.c
+++ b/boot_images/QcomPkg/Sdm660Pkg/Library/MDPPlatformLib/MDPPlatformLib.c
@@ -65,6 +65,7 @@ extern "C" {*/#define CDP_DISP_RESET_GPIO               53      //GPIO number for LCD0_RESET_N#define CDP_DISP_TE_GPIO                  59      //GPIO number for TE
+#define CDP_DISP_BL_EN_GPIO               76/* Helper macro for supported panels table entry PanelInfoType */#define PANEL_CREATE_ENTRY(_name_,_id_,_dtlable_,_interface_,_xml_,_cfg_,_pll_, _top0_, _top1_, _top2_)     \
@@ -535,7 +536,7 @@ const static int8 CM546B1_1080p_video_xmldata[] ="</DSITermSequence>\n""<Group id='Backlight Configuration'>"" <BacklightType units='MDP_Panel_BacklightType'>1</BacklightType>\n"
-" <BacklightPmicControlType units='MDP_PmicBacklightControlType'>2</BacklightPmicControlType>\n"
+" <BacklightPmicControlType units='MDP_PmicBacklightControlType'>1</BacklightPmicControlType>\n"" <DisplayResetInfo>0 10 10000 10000 0</DisplayResetInfo>\n""</Group>\n";/*added by cyl for lcd bring up JIRA:MC0310-2 --end*/
@@ -2140,6 +2141,11 @@ static MDP_Status Panel_CDP_PowerUp(MDP_Display_IDType eDisplayId, Panel_PowerCt{DEBUG((EFI_D_WARN, "DisplayDxe: Configure GPIO %d for TE line failed %d\n", CDP_DISP_TE_GPIO));}
+
+    TLMMProtocol->ConfigGpio((UINT32)EFI_GPIO_CFG(CDP_DISP_BL_EN_GPIO, 0, GPIO_OUTPUT, GPIO_PULL_UP, GPIO_2MA), TLMM_GPIO_ENABLE);
+    TLMMProtocol->GpioOut((UINT32)EFI_GPIO_CFG(CDP_DISP_BL_EN_GPIO, 0, GPIO_OUTPUT, GPIO_NO_PULL, GPIO_2MA), GPIO_HIGH_VALUE);}return Status;
@@ -2497,6 +2503,45 @@ static MDP_Status Panel_CDP_BacklightLevel(MDP_Display_IDType eDisplayId, Panel_}}break;
+    case MDP_PMIC_BACKLIGHT_CONTROLTYPE_LPG:
+         {
+           EFI_QCOM_PMIC_LPG_PROTOCOL *PmicLpgProtocol = NULL;
+               EFI_QCOM_PMIC_GPIO_PROTOCOL *PmicGpioProtocol = NULL;
+
+               if (EFI_SUCCESS != gBS->LocateProtocol(&gQcomPmicGpioProtocolGuid, NULL, (VOID **)&PmicGpioProtocol))
+               {
+                       Status = MDP_STATUS_NO_RESOURCES;
+               }
+               else
+               {
+                       Status = PmicGpioProtocol->ConfigDigitalOutput(PMIC_PMI_DEV_INDEX,
+                                                                           EFI_PM_GPIO_6,
+                                                                           EFI_PM_GPIO_OUT_BUFFER_CONFIG_CMOS,
+                                                                           EFI_PM_GPIO_VIN0,
+                                                                           EFI_PM_GPIO_SOURCE_SPECIAL_FUNCTION1,
+                                                                           EFI_PM_GPIO_OUT_BUFFER_LOW,
+                                                                           1);
+                       if (EFI_SUCCESS != Status)
+                       {
+                               Status = MDP_STATUS_FAILED;
+                       }
+               }
+
+        if (EFI_SUCCESS != gBS->LocateProtocol(&gQcomPmicLpgProtocolGuid, NULL, (VOID **)&PmicLpgProtocol))
+               {
+                 Status = MDP_STATUS_NO_RESOURCES;
+               }
+               else
+               {
+                 if (EFI_SUCCESS != PmicLpgProtocol->LpgConfig(PMIC_PMI_DEV_INDEX, EFI_PM_LPG_CHAN_4, 102, EFI_PM_LPG_PWM_PRE_DIV_6, EFI_PM_LPG_PWM_FREQ_EXPO_7, EFI_PM_LPG_PWM_CLOCK_19_2_MHZ
, EFI_PM_LPG_PWM_9BIT))
+                 {
+                   DEBUG((EFI_D_ERROR, "LPG Protocol LpgConfig failed\n"));
+                 }
+               }
+         }
+         break;default:break;}
diff --git a/boot_images/QcomPkg/Sdm660Pkg/Library/MDPPlatformLib/MDPPlatformLib.inf b/boot_images/QcomPkg/Sdm660Pkg/Library/MDPPlatformLib/MDPPlatformLib.inf
index 48a53320e..67f9a82bf 100755
--- a/boot_images/QcomPkg/Sdm660Pkg/Library/MDPPlatformLib/MDPPlatformLib.inf
+++ b/boot_images/QcomPkg/Sdm660Pkg/Library/MDPPlatformLib/MDPPlatformLib.inf
@@ -38,12 +38,14 @@[Protocols]gEfiPlatformInfoProtocolGuidgEfiChipInfoProtocolGuid
+ gQcomPmicLpgProtocolGuidgQcomPmicWledProtocolGuidgQcomPmicIbbProtocolGuidgQcomPmicLabProtocolGuidgQcomPmicVersionProtocolGuidgQcomPmicLcdbProtocolGuidgQcomPmicOledbProtocolGuid
+ gQcomPmicGpioProtocolGuidgEfiTLMMProtocolGuid

lpg模式配置中参数说明：

PmicLpgProtocol->LpgConfig(PMIC_PMI_DEV_INDEX, EFI_PM_LPG_CHAN_4, 102, EFI_PM_LPG_PWM_PRE_DIV_6, EFI_PM_LPG_PWM_FREQ_EXPO_7, EFI_PM_LPG_PWM_CLOCK_19_2_MHZ, EFI_PM_LPG_PWM_9BIT)

PMIC_PMI_DEV_INDEX：PMIC接口设备（LCD / OLED）这里配置为1

EFI_PM_LPG_CHAN_4 ：lpg通道，由所接gpio决定（芯片手册中可查看），选择channel4

EFI_PM_LPG_PWM_PRE_DIV_6 ：脉宽调制前置分频器值

EFI_PM_LPG_PWM_FREQ_EXPO_7：LPG脉宽调制频率指数值

EFI_PM_LPG_PWM_CLOCK_19_2_MHZ：脉宽调制时钟

EFI_PM_LPG_PWM_9BIT：脉宽调制比特大小

这里如果想配置PWM，如下：

+ uint32 uWLEDValue = (0x1FF * pBacklightConfig->uLevel) / 100; // Calculate duty cycle based on 12 bit mode
+
+               eLocalStatus = PMICPWMProtocol->PwmConfig(0,
+                                            EFI_PM_PWM_RSRC_PWM_1,
+                                            uWLEDValue,
+                                            1,
+                                            2,
+                                            EFI_PM_PWM_CLK_19_2_MHZ,
+                                            EFI_PM_PWM_SIZE_9BIT);

2、kernel配置

kernel配置如xbl，首先配置了gpio6的func，设备树添加pwms，驱动中通过of_pwm_get(np, NULL)获取设备树信息，然后通过pwm_config()函数即可调用。

diff --git a/fibo/common/kernel/msm-4.19/arch/arm64/boot/dts/qcom/sc218-evk/pm660l.dtsi b/fibo/common/kernel/msm-4.19/arch/arm64/boot/dts/qcom/sc218-evk/pm660l.dtsi
index e5fa849ac..255b5d002 100755
--- a/fibo/common/kernel/msm-4.19/arch/arm64/boot/dts/qcom/sc218-evk/pm660l.dtsi
+++ b/fibo/common/kernel/msm-4.19/arch/arm64/boot/dts/qcom/sc218-evk/pm660l.dtsi
@@ -58,6 +58,18 @@"pm660l_gpio11", "pm660l_gpio12";gpio-controller;#gpio-cells = <2>;
+
+                       pwm_bl {
+                               pwm_bl_default: pwm_bl_default {
+                                       pins = "gpio6";
+                                       function = "func1";
+                                       bias-disable;
+                                       power-source = <0>;
+                                       output-low;
+                                       qcom,drive-strength = <3>;
+                                       drive-push-pull;
+                               };
+                       };};};diff --git a/fibo/common/kernel/msm-4.19/arch/arm64/boot/dts/qcom/sc218-evk/sdm660-mtp.dtsi b/fibo/common/kernel/msm-4.19/arch/arm64/boot/dts/qcom/sc218-evk/sdm660-mtp.dtsi
index e24afcc00..eee65bee1 100755
--- a/fibo/common/kernel/msm-4.19/arch/arm64/boot/dts/qcom/sc218-evk/sdm660-mtp.dtsi
+++ b/fibo/common/kernel/msm-4.19/arch/arm64/boot/dts/qcom/sc218-evk/sdm660-mtp.dtsi
@@ -119,10 +119,11 @@&mdss_dsi0 {qcom,dsi-pref-prim-pan = <&dsi_CM546B1_1080p_video>;pinctrl-names = "mdss_default", "mdss_sleep";
-        pinctrl-0 = <&mdss_dsi_active &mdss_te_active>;
+        pinctrl-0 = <&mdss_dsi_active &mdss_te_active &pwm_bl_default>;pinctrl-1 = <&mdss_dsi_suspend &mdss_te_suspend>;qcom,platform-reset-gpio = <&tlmm 53 0>;qcom,platform-te-gpio = <&tlmm 59 0>;
+       qcom,platform-bklight-en-gpio = <&tlmm 76 0>;};@@ -188,9 +189,13 @@&dsi_CM546B1_1080p_video {
-        qcom,mdss-dsi-bl-pmic-control-type = "bl_ctrl_wled";
-        qcom,mdss-dsi-bl-min-level = <1>;
-        qcom,mdss-dsi-bl-max-level = <4095>;
+        qcom,mdss-dsi-bl-pmic-control-type = "bl_ctrl_pwm";
+       qcom,mdss-dsi-bl-pwm-pmi;
+       pwms = <&pm660l_pwm 0 1000000>;
+       qcom,bl-pmic-pwm-period-usecs = <100>;
+       qcom,mdss-dsi-bl-pmic-pwm-frequency = <1000000>;
+       qcom,mdss-dsi-bl-min-level = <1>;
+       qcom,mdss-dsi-bl-max-level = <4095>;qcom,panel-supply-entries = <&dsi_panel_pwr_supply>;};

参数说明：

pwms = <&pm660l_pwm 0 1000000>;

第一个参数表示此背光接在 pm660l_pwm 上;
第二个参数表示 index 为 0，pm660l_pwm下只有 1个 pwm，所以填 0
第三个参数表示周期为 1000000ns（1ms）

3、pwm背光简单debug