commit db8ae1bea4511df7c0dc93cd652f680e1e8f457e
author Sandeep Panda <spanda@codeaurora.org> Thu Aug 03 15:18:32 2017 -0700
committer Aravind Venkateswaran <aravindh@codeaurora.org> Fri Aug 04 13:29:36 2017 -0700
tree e2981fd82090970d8aaba021498f72d8a2557602
parent d98d9ee864a3982fd03c1ed56688b7d57fc4dcf2

drm/msm/dsi-staging: fix DSI controller init sequence

Ensure that all the DSI clocks are on and sourced correctly from the
DSI PLL prior to issuing the DSI controller software reset as part of
the initialization sequence. If the clocks are not correctly configured
then the soft reset may not take effect and can lead to DSI commands
transfer failures.

CRs-Fixed: 2085016
Change-Id: I582fcbc0dc1d57955e900c9ffa7e797454b4ba9c
Signed-off-by: Aravind Venkateswaran <aravindh@codeaurora.org>
Signed-off-by: Sandeep Panda <spanda@codeaurora.org>

drivers/gpu/drm/msm/dsi-staging/dsi_ctrl.c

diff --git a/drivers/gpu/drm/msm/dsi-staging/dsi_ctrl.c b/drivers/gpu/drm/msm/dsi-staging/dsi_ctrl.c
index 21ef811..6af4118 100644
--- a/drivers/gpu/drm/msm/dsi-staging/dsi_ctrl.c
+++ b/drivers/gpu/drm/msm/dsi-staging/dsi_ctrl.c
@@ -2002,8 +2002,6 @@
 	dsi_ctrl->hw.ops.enable_status_interrupts(&dsi_ctrl->hw, 0x0);
 	dsi_ctrl->hw.ops.enable_error_interrupts(&dsi_ctrl->hw, 0x0);
 
-	/* Perform a soft reset before enabling dsi controller */
-	dsi_ctrl->hw.ops.soft_reset(&dsi_ctrl->hw);
 	pr_debug("[DSI_%d]Host initialization complete\n",
 		dsi_ctrl->cell_index);
 	dsi_ctrl_update_state(dsi_ctrl, DSI_CTRL_OP_HOST_INIT, 0x1);

drivers/gpu/drm/msm/dsi-staging/dsi_display.c

diff --git a/drivers/gpu/drm/msm/dsi-staging/dsi_display.c b/drivers/gpu/drm/msm/dsi-staging/dsi_display.c
index c0c6698..34e6d03 100644
--- a/drivers/gpu/drm/msm/dsi-staging/dsi_display.c
+++ b/drivers/gpu/drm/msm/dsi-staging/dsi_display.c
@@ -3536,6 +3536,13 @@
 		goto error_ctrl_clk_off;
 	}
 
+	rc = dsi_display_set_clk_src(display);
+	if (rc) {
+		pr_err("[%s] failed to set DSI link clock source, rc=%d\n",
+			display->name, rc);
+		goto error_phy_disable;
+	}
+
 	rc = dsi_display_ctrl_init(display);
 	if (rc) {
 		pr_err("[%s] failed to setup DSI controller, rc=%d\n",
@@ -3543,10 +3550,10 @@
 		goto error_phy_disable;
 	}
 
-	rc = dsi_display_set_clk_src(display);
+	rc = dsi_display_ctrl_host_enable(display);
 	if (rc) {
-		pr_err("[%s] failed to set DSI link clock source, rc=%d\n",
-			display->name, rc);
+		pr_err("[%s] failed to enable DSI host, rc=%d\n",
+		       display->name, rc);
 		goto error_ctrl_deinit;
 	}
 
@@ -3555,29 +3562,28 @@
 	if (rc) {
 		pr_err("[%s] failed to enable DSI link clocks, rc=%d\n",
 		       display->name, rc);
-		goto error_ctrl_deinit;
+		goto error_host_engine_off;
 	}
 
-	rc = dsi_display_ctrl_host_enable(display);
+	rc = dsi_display_soft_reset(display);
 	if (rc) {
-		pr_err("[%s] failed to enable DSI host, rc=%d\n",
-		       display->name, rc);
+		pr_err("[%s] failed soft reset, rc=%d\n", display->name, rc);
 		goto error_ctrl_link_off;
 	}
 
 	rc = dsi_panel_prepare(display->panel);
 	if (rc) {
 		pr_err("[%s] panel prepare failed, rc=%d\n", display->name, rc);
-		goto error_host_engine_off;
+		goto error_ctrl_link_off;
 	}
 
 	goto error;
 
-error_host_engine_off:
-	(void)dsi_display_ctrl_host_disable(display);
 error_ctrl_link_off:
 	(void)dsi_display_clk_ctrl(display->dsi_clk_handle,
 			DSI_LINK_CLK, DSI_CLK_OFF);
+error_host_engine_off:
+	(void)dsi_display_ctrl_host_disable(display);
 error_ctrl_deinit:
 	(void)dsi_display_ctrl_deinit(display);
 error_phy_disable: