coresight: dynamic-replicator: Claim device for use

Use CLAIM protocol to make sure the device is available for use.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 18 insertions, 5 deletions

diff --git a/drivers/hwtracing/coresight/coresight-dynamic-replicator.c b/drivers/hwtracing/coresight/coresight-dynamic-replicator.c
index 97f4673452cb..299667b887fc 100644
--- a/drivers/hwtracing/coresight/coresight-dynamic-replicator.c
+++ b/drivers/hwtracing/coresight/coresight-dynamic-replicator.c
@@ -41,8 +41,11 @@ static void replicator_reset(struct replicator_state *drvdata)
 {
         CS_UNLOCK(drvdata->base);
 
-        writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER0);
-        writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER1);
+        if (!coresight_claim_device_unlocked(drvdata->base)) {
+                writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER0);
+                writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER1);
+                coresight_disclaim_device_unlocked(drvdata->base);
+        }
 
         CS_LOCK(drvdata->base);
 }
@@ -50,6 +53,7 @@ static void replicator_reset(struct replicator_state *drvdata)
 static int replicator_enable(struct coresight_device *csdev, int inport,
                               int outport)
 {
+        int rc = 0;
         u32 reg;
         struct replicator_state *drvdata = dev_get_drvdata(csdev->dev.parent);
 
@@ -67,13 +71,19 @@ static int replicator_enable(struct coresight_device *csdev, int inport,
 
         CS_UNLOCK(drvdata->base);
 
+        if ((readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0) == 0xff) &&
+            (readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1) == 0xff))
+                rc = coresight_claim_device_unlocked(drvdata->base);
 
         /* Ensure that the outport is enabled. */
-        writel_relaxed(0x00, drvdata->base + reg);
+        if (!rc) {
+                writel_relaxed(0x00, drvdata->base + reg);
+                dev_dbg(drvdata->dev, "REPLICATOR enabled\n");
+        }
+
         CS_LOCK(drvdata->base);
 
-        dev_dbg(drvdata->dev, "REPLICATOR enabled\n");
-        return 0;
+        return rc;
 }
 
 static void replicator_disable(struct coresight_device *csdev, int inport,
@@ -99,6 +109,9 @@ static void replicator_disable(struct coresight_device *csdev, int inport,
         /* disable the flow of ATB data through port */
         writel_relaxed(0xff, drvdata->base + reg);
 
+        if ((readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0) == 0xff) &&
+            (readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1) == 0xff))
+                coresight_disclaim_device_unlocked(drvdata->base);
         CS_LOCK(drvdata->base);
 
         dev_dbg(drvdata->dev, "REPLICATOR disabled\n");