coresight: Introduce generic platform data helper

So far we have hard coded the DT platform parsing code in
every driver. Introduce generic helper to parse the information
provided by the firmware in a platform agnostic manner, in preparation
for the ACPI support.

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, 43 insertions, 15 deletions

diff --git a/drivers/hwtracing/coresight/coresight-platform.c b/drivers/hwtracing/coresight/coresight-platform.c
index 4c31299607cf..5d78f4fbd97d 100644
--- a/drivers/hwtracing/coresight/coresight-platform.c
+++ b/drivers/hwtracing/coresight/coresight-platform.c
@@ -230,23 +230,16 @@ static int of_coresight_parse_endpoint(struct device *dev,
 	return ret;
 }
 
-struct coresight_platform_data *
-of_get_coresight_platform_data(struct device *dev,
-			       const struct device_node *node)
+static int of_get_coresight_platform_data(struct device *dev,
+					  struct coresight_platform_data *pdata)
 {
 	int ret = 0;
-	struct coresight_platform_data *pdata;
 	struct coresight_connection *conn;
 	struct device_node *ep = NULL;
 	const struct device_node *parent = NULL;
 	bool legacy_binding = false;
+	struct device_node *node = dev->of_node;
 
-	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
-	if (!pdata)
-		return ERR_PTR(-ENOMEM);
-
-	/* Use device name as sysfs handle */
-	pdata->name = dev_name(dev);
 	pdata->cpu = of_coresight_get_cpu(node);
 
 	/* Get the number of input and output port for this component */
@@ -254,11 +247,11 @@ of_get_coresight_platform_data(struct device *dev,
 
 	/* If there are no output connections, we are done */
 	if (!pdata->nr_outport)
-		return pdata;
+		return 0;
 
 	ret = coresight_alloc_conns(dev, pdata);
 	if (ret)
-		return ERR_PTR(ret);
+		return ret;
 
 	parent = of_coresight_get_output_ports_node(node);
 	/*
@@ -292,11 +285,46 @@ of_get_coresight_platform_data(struct device *dev,
 		case 0:
 			break;
 		default:
-			return ERR_PTR(ret);
+			return ret;
 		}
 	}
 
-	return pdata;
+	return 0;
+}
+#else
+static inline int
+of_get_coresight_platform_data(struct device *dev,
+			       struct coresight_platform_data *pdata)
+{
+	return -ENOENT;
 }
-EXPORT_SYMBOL_GPL(of_get_coresight_platform_data);
 #endif
+
+struct coresight_platform_data *
+coresight_get_platform_data(struct device *dev)
+{
+	int ret = -ENOENT;
+	struct coresight_platform_data *pdata;
+	struct fwnode_handle *fwnode = dev_fwnode(dev);
+
+	if (IS_ERR_OR_NULL(fwnode))
+		goto error;
+
+	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata) {
+		ret = -ENOMEM;
+		goto error;
+	}
+
+	/* Use device name as sysfs handle */
+	pdata->name = dev_name(dev);
+
+	if (is_of_node(fwnode))
+		ret = of_get_coresight_platform_data(dev, pdata);
+
+	if (!ret)
+		return pdata;
+error:
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(coresight_get_platform_data);