1 files changed, 39 insertions, 9 deletions

diff --git a/drivers/hwtracing/coresight/coresight-funnel.c b/drivers/hwtracing/coresight/coresight-funnel.c
index fa97cb9ab4f9..900690a9f7f0 100644
--- a/drivers/hwtracing/coresight/coresight-funnel.c
+++ b/drivers/hwtracing/coresight/coresight-funnel.c
@@ -5,6 +5,7 @@
  * Description: CoreSight Funnel driver
  */
 
+#include <linux/acpi.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/types.h>
@@ -37,12 +38,14 @@ DEFINE_CORESIGHT_DEVLIST(funnel_devs, "funnel");
  * @atclk:	optional clock for the core parts of the funnel.
  * @csdev:	component vitals needed by the framework.
  * @priority:	port selection order.
+ * @spinlock:	serialize enable/disable operations.
  */
 struct funnel_drvdata {
 	void __iomem		*base;
 	struct clk		*atclk;
 	struct coresight_device	*csdev;
 	unsigned long		priority;
+	spinlock_t		spinlock;
 };
 
 static int dynamic_funnel_enable_hw(struct funnel_drvdata *drvdata, int port)
@@ -75,11 +78,21 @@ static int funnel_enable(struct coresight_device *csdev, int inport,
 {
 	int rc = 0;
 	struct funnel_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
-
-	if (drvdata->base)
-		rc = dynamic_funnel_enable_hw(drvdata, inport);
-
+	unsigned long flags;
+	bool first_enable = false;
+
+	spin_lock_irqsave(&drvdata->spinlock, flags);
+	if (atomic_read(&csdev->refcnt[inport]) == 0) {
+		if (drvdata->base)
+			rc = dynamic_funnel_enable_hw(drvdata, inport);
+		if (!rc)
+			first_enable = true;
+	}
 	if (!rc)
+		atomic_inc(&csdev->refcnt[inport]);
+	spin_unlock_irqrestore(&drvdata->spinlock, flags);
+
+	if (first_enable)
 		dev_dbg(&csdev->dev, "FUNNEL inport %d enabled\n", inport);
 	return rc;
 }
@@ -106,11 +119,19 @@ static void funnel_disable(struct coresight_device *csdev, int inport,
 			   int outport)
 {
 	struct funnel_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+	unsigned long flags;
+	bool last_disable = false;
+
+	spin_lock_irqsave(&drvdata->spinlock, flags);
+	if (atomic_dec_return(&csdev->refcnt[inport]) == 0) {
+		if (drvdata->base)
+			dynamic_funnel_disable_hw(drvdata, inport);
+		last_disable = true;
+	}
+	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
-	if (drvdata->base)
-		dynamic_funnel_disable_hw(drvdata, inport);
-
-	dev_dbg(&csdev->dev, "FUNNEL inport %d disabled\n", inport);
+	if (last_disable)
+		dev_dbg(&csdev->dev, "FUNNEL inport %d disabled\n", inport);
 }
 
 static const struct coresight_ops_link funnel_link_ops = {
@@ -192,7 +213,7 @@ static int funnel_probe(struct device *dev, struct resource *res)
 
 	if (is_of_node(dev_fwnode(dev)) &&
 	    of_device_is_compatible(dev->of_node, "arm,coresight-funnel"))
-		pr_warn_once("Uses OBSOLETE CoreSight funnel binding\n");
+		dev_warn_once(dev, "Uses OBSOLETE CoreSight funnel binding\n");
 
 	desc.name = coresight_alloc_device_name(&funnel_devs, dev);
 	if (!desc.name)
@@ -232,6 +253,7 @@ static int funnel_probe(struct device *dev, struct resource *res)
 	}
 	dev->platform_data = pdata;
 
+	spin_lock_init(&drvdata->spinlock);
 	desc.type = CORESIGHT_DEV_TYPE_LINK;
 	desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_MERG;
 	desc.ops = &funnel_cs_ops;
@@ -302,11 +324,19 @@ static const struct of_device_id static_funnel_match[] = {
 	{}
 };
 
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id static_funnel_ids[] = {
+	{"ARMHC9FE", 0},
+	{},
+};
+#endif
+
 static struct platform_driver static_funnel_driver = {
 	.probe          = static_funnel_probe,
 	.driver         = {
 		.name   = "coresight-static-funnel",
 		.of_match_table = static_funnel_match,
+		.acpi_match_table = ACPI_PTR(static_funnel_ids),
 		.pm	= &funnel_dev_pm_ops,
 		.suppress_bind_attrs = true,
 	},