[PATCH] coresight: Add coresight name support

[Mao Jinlong]

Add coresight name support for custom names which will be
easy to identify the device by the name.

Signed-off-by: Mao Jinlong <quic_jinlmao at quicinc.com>
---
 .../hwtracing/coresight/coresight-cti-core.c  | 20 ++++++++------
 drivers/hwtracing/coresight/coresight-dummy.c | 10 ++++---
 .../hwtracing/coresight/coresight-platform.c  | 27 +++++++++++++++++++
 drivers/hwtracing/coresight/coresight-tpdm.c  | 10 ++++---
 include/linux/coresight.h                     |  1 +
 5 files changed, 53 insertions(+), 15 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-cti-core.c b/drivers/hwtracing/coresight/coresight-cti-core.c
index 3999d0a2cb60..60a1e76064a9 100644
--- a/drivers/hwtracing/coresight/coresight-cti-core.c
+++ b/drivers/hwtracing/coresight/coresight-cti-core.c
@@ -902,14 +902,18 @@ static int cti_probe(struct amba_device *adev, const struct amba_id *id)
 	/* default to powered - could change on PM notifications */
 	drvdata->config.hw_powered = true;
 
-	/* set up device name - will depend if cpu bound or otherwise */
-	if (drvdata->ctidev.cpu >= 0)
-		cti_desc.name = devm_kasprintf(dev, GFP_KERNEL, "cti_cpu%d",
-					       drvdata->ctidev.cpu);
-	else
-		cti_desc.name = coresight_alloc_device_name(&cti_sys_devs, dev);
-	if (!cti_desc.name)
-		return -ENOMEM;
+	cti_desc.name = coresight_get_device_name(dev);
+	if (!cti_desc.name) {
+		/* set up device name - will depend if cpu bound or otherwise */
+		if (drvdata->ctidev.cpu >= 0)
+			cti_desc.name = devm_kasprintf(dev, GFP_KERNEL, "cti_cpu%d",
+						       drvdata->ctidev.cpu);
+		else {
+			cti_desc.name = coresight_alloc_device_name(&cti_sys_devs, dev);
+			if (!cti_desc.name)
+				return -ENOMEM;
+		}
+	}
 
 	/* setup CPU power management handling for CPU bound CTI devices. */
 	ret = cti_pm_setup(drvdata);
diff --git a/drivers/hwtracing/coresight/coresight-dummy.c b/drivers/hwtracing/coresight/coresight-dummy.c
index e4deafae7bc2..b19cd400df79 100644
--- a/drivers/hwtracing/coresight/coresight-dummy.c
+++ b/drivers/hwtracing/coresight/coresight-dummy.c
@@ -76,10 +76,12 @@ static int dummy_probe(struct platform_device *pdev)
 	struct coresight_desc desc = { 0 };
 
 	if (of_device_is_compatible(node, "arm,coresight-dummy-source")) {
-
-		desc.name = coresight_alloc_device_name(&source_devs, dev);
-		if (!desc.name)
-			return -ENOMEM;
+		desc.name = coresight_get_device_name(dev);
+		if (!desc.name) {
+			desc.name = coresight_alloc_device_name(&source_devs, dev);
+			if (!desc.name)
+				return -ENOMEM;
+		}
 
 		desc.type = CORESIGHT_DEV_TYPE_SOURCE;
 		desc.subtype.source_subtype =
diff --git a/drivers/hwtracing/coresight/coresight-platform.c b/drivers/hwtracing/coresight/coresight-platform.c
index 9d550f5697fa..284aa22a06b7 100644
--- a/drivers/hwtracing/coresight/coresight-platform.c
+++ b/drivers/hwtracing/coresight/coresight-platform.c
@@ -183,6 +183,18 @@ static int of_coresight_get_cpu(struct device *dev)
 	return cpu;
 }
 
+static const char *of_coresight_get_device_name(struct device *dev)
+{
+	const char *name = NULL;
+
+	if (!dev->of_node)
+		return NULL;
+
+	of_property_read_string(dev->of_node, "coresight-name", &name);
+
+	return name;
+}
+
 /*
  * of_coresight_parse_endpoint : Parse the given output endpoint @ep
  * and fill the connection information in @pdata->out_conns
@@ -315,6 +327,12 @@ static inline int of_coresight_get_cpu(struct device *dev)
 {
 	return -ENODEV;
 }
+
+static inline const char *of_coresight_get_device_name(struct device *dev)
+{
+	return NULL;
+}
+
 #endif
 
 #ifdef CONFIG_ACPI
@@ -794,6 +812,15 @@ int coresight_get_cpu(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(coresight_get_cpu);
 
+const char *coresight_get_device_name(struct device *dev)
+{
+	if (is_of_node(dev->fwnode))
+		return of_coresight_get_device_name(dev);
+	else
+		return NULL;
+}
+EXPORT_SYMBOL_GPL(coresight_get_device_name);
+
 struct coresight_platform_data *
 coresight_get_platform_data(struct device *dev)
 {
diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c b/drivers/hwtracing/coresight/coresight-tpdm.c
index f4854af0431e..7735ff18c48e 100644
--- a/drivers/hwtracing/coresight/coresight-tpdm.c
+++ b/drivers/hwtracing/coresight/coresight-tpdm.c
@@ -201,9 +201,13 @@ static int tpdm_probe(struct amba_device *adev, const struct amba_id *id)
 	drvdata->base = base;
 
 	/* Set up coresight component description */
-	desc.name = coresight_alloc_device_name(&tpdm_devs, dev);
-	if (!desc.name)
-		return -ENOMEM;
+	desc.name = coresight_get_device_name(dev);
+	if (!desc.name) {
+		desc.name = coresight_alloc_device_name(&tpdm_devs, dev);
+		if (!desc.name)
+			return -ENOMEM;
+	}
+
 	desc.type = CORESIGHT_DEV_TYPE_SOURCE;
 	desc.subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_OTHERS;
 	desc.ops = &tpdm_cs_ops;
diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index a269fffaf991..caa17c8af865 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -675,6 +675,7 @@ static inline void coresight_write64(struct coresight_device *csdev, u64 val, u3
 #endif		/* IS_ENABLED(CONFIG_CORESIGHT) */
 
 extern int coresight_get_cpu(struct device *dev);
+extern const char *coresight_get_device_name(struct device *dev);
 
 struct coresight_platform_data *coresight_get_platform_data(struct device *dev);
 struct coresight_connection *
-- 
2.41.0