bus: ti-sysc: Improve suspend and resume handling

Based on testing with more devices I noticed that some devices
don't suspend or resume properly. We need to PM runtime suspend
and resume devices if we have ddata->needs_resume set.

Let's also improve the error handling and add few debug statements
to make it easier to notice suspend and resume related issues if
DEBUG is set.

Signed-off-by: Tony Lindgren <tony@atomide.com>

1 files changed, 48 insertions, 6 deletions

diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c
index 1f90b91dbfae..145dcc0cf48c 100644
--- a/drivers/bus/ti-sysc.c
+++ b/drivers/bus/ti-sysc.c
@@ -662,6 +662,7 @@ awake:
 static int sysc_suspend(struct device *dev)
 {
         struct sysc *ddata;
+        int error;
 
         ddata = dev_get_drvdata(dev);
 
@@ -672,14 +673,27 @@ static int sysc_suspend(struct device *dev)
         if (!ddata->enabled)
                 return 0;
 
+        dev_dbg(ddata->dev, "%s %s\n", __func__,
+                ddata->name ? ddata->name : "");
+
+        error = pm_runtime_put_sync_suspend(dev);
+        if (error < 0) {
+                dev_warn(ddata->dev, "%s not idle %i %s\n",
+                         __func__, error,
+                         ddata->name ? ddata->name : "");
+
+                return 0;
+        }
+
         ddata->needs_resume = true;
 
-        return sysc_runtime_suspend(dev);
+        return 0;
 }
 
 static int sysc_resume(struct device *dev)
 {
         struct sysc *ddata;
+        int error;
 
         ddata = dev_get_drvdata(dev);
 
@@ -691,9 +705,16 @@ static int sysc_resume(struct device *dev)
                 dev_dbg(ddata->dev, "%s %s\n", __func__,
                         ddata->name ? ddata->name : "");
 
-                ddata->needs_resume = false;
+                error = pm_runtime_get_sync(dev);
+                if (error < 0) {
+                        dev_err(ddata->dev, "%s  error %i %s\n",
+                                __func__, error,
+                                 ddata->name ? ddata->name : "");
 
-                return sysc_runtime_resume(dev);
+                        return error;
+                }
+
+                ddata->needs_resume = false;
         }
 
         return 0;
@@ -735,6 +756,9 @@ static int sysc_noirq_resume(struct device *dev)
                 return 0;
 
         if (ddata->needs_resume) {
+                dev_dbg(ddata->dev, "%s %s\n", __func__,
+                        ddata->name ? ddata->name : "");
+
                 ddata->needs_resume = false;
 
                 return sysc_runtime_resume(dev);
@@ -1069,18 +1093,33 @@ static int sysc_child_suspend_noirq(struct device *dev)
 
         ddata = sysc_child_to_parent(dev);
 
+        dev_dbg(ddata->dev, "%s %s\n", __func__,
+                ddata->name ? ddata->name : "");
+
         error = pm_generic_suspend_noirq(dev);
-        if (error)
+        if (error) {
+                dev_err(dev, "%s error at %i: %i\n",
+                        __func__, __LINE__, error);
+
                 return error;
+        }
 
         if (!pm_runtime_status_suspended(dev)) {
                 error = pm_generic_runtime_suspend(dev);
-                if (error)
+                if (error) {
+                        dev_err(dev, "%s error at %i: %i\n",
+                                __func__, __LINE__, error);
+
                         return error;
+                }
 
                 error = sysc_runtime_suspend(ddata->dev);
-                if (error)
+                if (error) {
+                        dev_err(dev, "%s error at %i: %i\n",
+                                __func__, __LINE__, error);
+
                         return error;
+                }
 
                 ddata->child_needs_resume = true;
         }
@@ -1095,6 +1134,9 @@ static int sysc_child_resume_noirq(struct device *dev)
 
         ddata = sysc_child_to_parent(dev);
 
+        dev_dbg(ddata->dev, "%s %s\n", __func__,
+                ddata->name ? ddata->name : "");
+
         if (ddata->child_needs_resume) {
                 ddata->child_needs_resume = false;