高通821平台LCD调试（7）:Kernel部分流程（二）

总目录：高通821平台LCD调试

可以看到mdss_dsi_ctrl_probe这个接口实际上时初始化的最终执行者，继续分析这个接口内部的实现流程，主要是上电使能和屏初始化。

一、上电使能

1. probe函数中会调用Panel的注册函数：dsi_panel_device_register

rc = dsi_panel_device_register(pdev, dsi_pan_node, ctrl_pdata);

然后在注册函数中会填充事件处理函数的处理接口：mdss_dsi_event_handler

ctrl_pdata->panel_data.event_handler = mdss_dsi_event_handler;

然后在LINK_READY时，调用mdss_dsi_on

	case MDSS_EVENT_LINK_READY:
		if (ctrl_pdata->refresh_clk_rate)
			rc = mdss_dsi_clk_refresh(pdata,
				ctrl_pdata->update_phy_timing);

		rc = mdss_dsi_on(pdata);
		pr_info("SOLEN MDSS_EVENT_LINK_READY\n");
		mdss_dsi_op_mode_config(pdata->panel_info.mipi.mode,
							pdata);
		break;

然后mdss_dsi_on调用power_ctrl

ret = mdss_dsi_panel_power_ctrl(pdata, MDSS_PANEL_POWER_ON);

继续追踪，上电时会调用mdss_dsi_panel_power_on

	case MDSS_PANEL_POWER_ON:
		if (mdss_dsi_is_panel_on_lp(pdata))
			ret = mdss_dsi_panel_power_lp(pdata, false);
		else
			ret = mdss_dsi_panel_power_on(pdata);
		break;

最终实现如下：

static int mdss_dsi_panel_power_on(struct mdss_panel_data *pdata)
{
	int ret = 0;
	int i = 0;
	struct mdss_dsi_ctrl_pdata *ctrl_pdata = NULL;

	if (pdata == NULL) {
		pr_err("%s: Invalid input data\n", __func__);
		return -EINVAL;
	}

	ctrl_pdata = container_of(pdata, struct mdss_dsi_ctrl_pdata,
				panel_data);

#if ((defined DISPLAY_TIANMA_2K_VIDEO_PANEL) || (defined DISPLAY_BOE_4K_DSC_CMD_PANEL) || (defined DISPLAY_TIANMA_2K90_DSC_VIDEO_PANEL))/*modified by PICO_driver webber.wang for bug 14410 - BOE 4K lcd debug*/
/*modified by webber.wang to fix Bug 14244:lcd will go out when going to kernel --start--*/
	if(0 == boot_on){
		boot_on++;
		ret = msm_dss_enable_vreg(
						ctrl_pdata->panel_power_data.vreg_config,
						ctrl_pdata->panel_power_data.num_vreg, 1);
		for(i=0;i < ctrl_pdata->panel_power_data.num_vreg;i++)
			{
				pr_info("SOLEN in %s line292,num_vreg = %d,vreg=%s\n",__func__,i,ctrl_pdata->panel_power_data.vreg_config[i].vreg_name);
			}
		if (ret) {
			pr_err("%s: failed to enable vregs for %s\n",
				__func__, __mdss_dsi_pm_name(DSI_PANEL_PM));
			return ret;
		}
	}
	/*added by PICO_driver jim.qiu for bug13856:debug tianma lcd,fix flicker of LCD when resume system  --end--*/
	else{
		/*added by PICO_driver jim.qiu for bug13856:debug tianma lcd,fix flicker of LCD when resume system  --start--*/
		ret = msm_dss_enable_vreg(
			ctrl_pdata->panel_power_data.vreg_config,
			ctrl_pdata->panel_power_data.num_vreg-1, 1);
		if (ret) {
			pr_err("%s: failed to enable vregs for %s\n",
				__func__, __mdss_dsi_pm_name(DSI_PANEL_PM));
			return ret;
		}
	}
/*modified by webber.wang to fix Bug 14244:lcd will go out when going to kernel --end--*/
#else
	ret = msm_dss_enable_vreg(
		ctrl_pdata->panel_power_data.vreg_config,
		ctrl_pdata->panel_power_data.num_vreg, 1);
	if (ret) {
		pr_err("%s: failed to enable vregs for %s\n",
			__func__, __mdss_dsi_pm_name(DSI_PANEL_PM));
		return ret;
	}

#endif
	/*
	 * If continuous splash screen feature is enabled, then we need to
	 * request all the GPIOs that have already been configured in the
	 * bootloader. This needs to be done irresepective of whether
	 * the lp11_init flag is set or not.
	 */
	if (pdata->panel_info.cont_splash_enabled ||
		!pdata->panel_info.mipi.lp11_init) {
		if (mdss_dsi_pinctrl_set_state(ctrl_pdata, true))
			pr_debug("reset enable: pinctrl not enabled\n");

		ret = mdss_dsi_panel_reset(pdata, 1);
		if (ret)
			pr_err("%s: Panel reset failed. rc=%d\n",
					__func__, ret);
	}

	return ret;
}

打印的LOg为

[    1.574276] SOLEN in mdss_dsi_panel_power_on line292,num_vreg = 0,vreg=vddio
[    1.574281] SOLEN in mdss_dsi_panel_power_on line292,num_vreg = 1,vreg=lab
[    1.574285] SOLEN in mdss_dsi_panel_power_on line292,num_vreg = 2,vreg=ibb
[    1.574288] SOLEN in mdss_dsi_panel_power_on line292,num_vreg = 3,vreg=oled-vdda
这显然都是在设备树中dsi_panel_pwr_supply中定义的电源。

即依次给这四路电源上电

二、Panel初始化

首先看一下event时间的状态切换：

1. 开始亮屏时：

[    1.606577] SOLEN MDSS_EVENT_FB_REGISTERED
[    1.606694] SOLEN MDSS_EVENT_FB_REGISTERED
[    1.606971] SOLEN MDSS_EVENT_REGISTER_RECOVERY_HANDLER
[    1.606976] SOLEN MDSS_EVENT_REGISTER_RECOVERY_HANDLER
[    1.607021] SOLEN MDSS_EVENT_REGISTER_RECOVERY_HANDLER
[   18.672811] SOLEN MDSS_EVENT_LINK_READY
[   18.672837] SOLEN MDSS_EVENT_LINK_READY
[   18.672882] SOLEN MDSS_EVENT_UNBLANK
[   18.672900] SOLEN MDSS_EVENT_UNBLANK
[   18.676632] SOLEN MDSS_EVENT_PANEL_ON
[   18.676641] SOLEN MDSS_EVENT_PANEL_ON
[   18.676653] SOLEN MDSS_EVENT_POST_PANEL_ON
[   18.676665] SOLEN MDSS_EVENT_POST_PANEL_ON

2. 休眠灭屏时

[  110.840325] SOLEN MDSS_EVENT_BLANK
[  111.026104] SOLEN MDSS_EVENT_BLANK
[  111.067714] SOLEN MDSS_EVENT_PANEL_OFF
[  111.094403] SOLEN MDSS_EVENT_PANEL_OFF

主要看一下PANEL_ON和POST_PANEL_ON的流程：

待补充