drm/msm/dp: Remove global g_dp_display variable

As the Qualcomm DisplayPort driver only supports a single instance of
the driver the commonly used struct dp_display is kept in a global
variable. As we introduce additional instances this obviously doesn't
work.

Replace this with a combination of existing references to adjacent
objects and drvdata.
Reviewed-by: Abhinav Kumar <abhinavk@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20211016221843.2167329-2-bjorn.andersson@linaro.orgSigned-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/dp/dp_display.c

@@ -27,7 +27,6 @@
 #include "dp_audio.h"
 #include "dp_debug.h"
 
-static struct msm_dp *g_dp_display;
 #define HPD_STRING_SIZE 30
 
 enum {
@@ -121,6 +120,13 @@ static const struct of_device_id dp_dt_match[] = {
 	{}
 };
 
+static struct dp_display_private *dev_get_dp_display_private(struct device *dev)
+{
+	struct msm_dp *dp = dev_get_drvdata(dev);
+
+	return container_of(dp, struct dp_display_private, dp_display);
+}
+
 static int dp_add_event(struct dp_display_private *dp_priv, u32 event,
 						u32 data, u32 delay)
 {
@@ -197,15 +203,12 @@ static int dp_display_bind(struct device *dev, struct device *master,
 			   void *data)
 {
 	int rc = 0;
-	struct dp_display_private *dp;
-	struct drm_device *drm;
+	struct dp_display_private *dp = dev_get_dp_display_private(dev);
 	struct msm_drm_private *priv;
+	struct drm_device *drm;
 
 	drm = dev_get_drvdata(master);
 
-	dp = container_of(g_dp_display,
-			struct dp_display_private, dp_display);
-
 	dp->dp_display.drm_dev = drm;
 	priv = drm->dev_private;
 	priv->dp = &(dp->dp_display);
@@ -240,13 +243,10 @@ static int dp_display_bind(struct device *dev, struct device *master,
 static void dp_display_unbind(struct device *dev, struct device *master,
 			      void *data)
 {
-	struct dp_display_private *dp;
+	struct dp_display_private *dp = dev_get_dp_display_private(dev);
 	struct drm_device *drm = dev_get_drvdata(master);
 	struct msm_drm_private *priv = drm->dev_private;
 
-	dp = container_of(g_dp_display,
-			struct dp_display_private, dp_display);
-
 	dp_power_client_deinit(dp->power);
 	dp_aux_unregister(dp->aux);
 	priv->dp = NULL;
@@ -379,38 +379,17 @@ static void dp_display_host_deinit(struct dp_display_private *dp)
 
 static int dp_display_usbpd_configure_cb(struct device *dev)
 {
-	int rc = 0;
-	struct dp_display_private *dp;
-
-	if (!dev) {
-		DRM_ERROR("invalid dev\n");
-		rc = -EINVAL;
-		goto end;
-	}
-
-	dp = container_of(g_dp_display,
-			struct dp_display_private, dp_display);
+	struct dp_display_private *dp = dev_get_dp_display_private(dev);
 
 	dp_display_host_init(dp, false);
 
-	rc = dp_display_process_hpd_high(dp);
-end:
-	return rc;
+	return dp_display_process_hpd_high(dp);
 }
 
 static int dp_display_usbpd_disconnect_cb(struct device *dev)
 {
 	int rc = 0;
-	struct dp_display_private *dp;
-
-	if (!dev) {
-		DRM_ERROR("invalid dev\n");
-		rc = -EINVAL;
-		return rc;
-	}
-
-	dp = container_of(g_dp_display,
-			struct dp_display_private, dp_display);
+	struct dp_display_private *dp = dev_get_dp_display_private(dev);
 
 	dp_add_event(dp, EV_USER_NOTIFICATION, false, 0);
 
@@ -472,15 +451,7 @@ static int dp_display_usbpd_attention_cb(struct device *dev)
 {
 	int rc = 0;
 	u32 sink_request;
-	struct dp_display_private *dp;
-
-	if (!dev) {
-		DRM_ERROR("invalid dev\n");
-		return -EINVAL;
-	}
-
-	dp = container_of(g_dp_display,
-			struct dp_display_private, dp_display);
+	struct dp_display_private *dp = dev_get_dp_display_private(dev);
 
 	/* check for any test request issued by sink */
 	rc = dp_link_process_request(dp->link);
@@ -647,7 +618,7 @@ static int dp_hpd_unplug_handle(struct dp_display_private *dp, u32 data)
 
 	DRM_DEBUG_DP("hpd_state=%d\n", state);
 	/* signal the disconnect event early to ensure proper teardown */
-	dp_display_handle_plugged_change(g_dp_display, false);
+	dp_display_handle_plugged_change(&dp->dp_display, false);
 
 	/* enable HDP plug interrupt to prepare for next plugin */
 	dp_catalog_hpd_config_intr(dp->catalog, DP_DP_HPD_PLUG_INT_MASK, true);
@@ -842,9 +813,7 @@ static int dp_display_prepare(struct msm_dp *dp)
 static int dp_display_enable(struct dp_display_private *dp, u32 data)
 {
 	int rc = 0;
-	struct msm_dp *dp_display;
-
-	dp_display = g_dp_display;
+	struct msm_dp *dp_display = &dp->dp_display;
 
 	DRM_DEBUG_DP("sink_count=%d\n", dp->link->sink_count);
 	if (dp_display->power_on) {
@@ -880,9 +849,7 @@ static int dp_display_post_enable(struct msm_dp *dp_display)
 
 static int dp_display_disable(struct dp_display_private *dp, u32 data)
 {
-	struct msm_dp *dp_display;
-
-	dp_display = g_dp_display;
+	struct msm_dp *dp_display = &dp->dp_display;
 
 	if (!dp_display->power_on)
 		return 0;
@@ -1237,14 +1204,13 @@ static int dp_display_probe(struct platform_device *pdev)
 	}
 
 	mutex_init(&dp->event_mutex);
-	g_dp_display = &dp->dp_display;
 
 	/* Store DP audio handle inside DP display */
-	g_dp_display->dp_audio = dp->audio;
+	dp->dp_display.dp_audio = dp->audio;
 
 	init_completion(&dp->audio_comp);
 
-	platform_set_drvdata(pdev, g_dp_display);
+	platform_set_drvdata(pdev, &dp->dp_display);
 
 	rc = component_add(&pdev->dev, &dp_display_comp_ops);
 	if (rc) {
@@ -1257,10 +1223,7 @@ static int dp_display_probe(struct platform_device *pdev)
 
 static int dp_display_remove(struct platform_device *pdev)
 {
-	struct dp_display_private *dp;
-
-	dp = container_of(g_dp_display,
-			struct dp_display_private, dp_display);
+	struct dp_display_private *dp = dev_get_dp_display_private(&pdev->dev);
 
 	dp_display_deinit_sub_modules(dp);
 
@@ -1315,7 +1278,7 @@ static int dp_pm_resume(struct device *dev)
 		dp->dp_display.is_connected = true;
 	} else {
 		dp->dp_display.is_connected = false;
-		dp_display_handle_plugged_change(g_dp_display, false);
+		dp_display_handle_plugged_change(dp_display, false);
 	}
 
 	DRM_DEBUG_DP("After, sink_count=%d is_connected=%d core_inited=%d power_on=%d\n",