coresight: cti: Add function to register cti associate ops

Add static cti_assoc_ops to coresight core driver. Let cti
driver register the add_assoc and remove_assoc call back.
Avoid coresight core driver to depend on cti driver.
Tested-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200928163513.70169-17-mathieu.poirier@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/hwtracing/coresight/coresight-cti.c

@@ -539,7 +539,7 @@ cti_match_fixup_csdev(struct cti_device *ctidev, const char *node_name,
  * This will set the association if CTI declared before the CS device.
  * (called from coresight_register() with coresight_mutex locked).
  */
-void cti_add_assoc_to_csdev(struct coresight_device *csdev)
+static void cti_add_assoc_to_csdev(struct coresight_device *csdev)
 {
 	struct cti_drvdata *ect_item;
 	struct cti_device *ctidev;
@@ -572,13 +572,12 @@ void cti_add_assoc_to_csdev(struct coresight_device *csdev)
 cti_add_done:
 	mutex_unlock(&ect_mutex);
 }
-EXPORT_SYMBOL_GPL(cti_add_assoc_to_csdev);
 
 /*
  * Removing the associated devices is easier.
  * A CTI will not have a value for csdev->ect_dev.
  */
-void cti_remove_assoc_from_csdev(struct coresight_device *csdev)
+static void cti_remove_assoc_from_csdev(struct coresight_device *csdev)
 {
 	struct cti_drvdata *ctidrv;
 	struct cti_trig_con *tc;
@@ -599,7 +598,15 @@ void cti_remove_assoc_from_csdev(struct coresight_device *csdev)
 	}
 	mutex_unlock(&ect_mutex);
 }
-EXPORT_SYMBOL_GPL(cti_remove_assoc_from_csdev);
+
+/*
+ * Operations to add and remove associated CTI.
+ * Register to coresight core driver as call back function.
+ */
+static struct cti_assoc_op cti_assoc_ops = {
+	.add = cti_add_assoc_to_csdev,
+	.remove = cti_remove_assoc_from_csdev
+};
 
 /*
  * Update the cross references where the associated device was found
@@ -956,4 +963,23 @@ static struct amba_driver cti_driver = {
 	.probe		= cti_probe,
 	.id_table	= cti_ids,
 };
-builtin_amba_driver(cti_driver);
+
+static int __init cti_init(void)
+{
+	int ret;
+
+	ret = amba_driver_register(&cti_driver);
+	if (ret)
+		pr_info("Error registering cti driver\n");
+	coresight_set_cti_ops(&cti_assoc_ops);
+	return ret;
+}
+
+static void __exit cti_exit(void)
+{
+	coresight_remove_cti_ops();
+	amba_driver_unregister(&cti_driver);
+}
+
+module_init(cti_init);
+module_exit(cti_exit);

drivers/hwtracing/coresight/coresight-priv.h

@@ -173,15 +173,13 @@ static inline int etm_readl_cp14(u32 off, unsigned int *val) { return 0; }
 static inline int etm_writel_cp14(u32 off, u32 val) { return 0; }
 #endif
 
-#ifdef CONFIG_CORESIGHT_CTI
-extern void cti_add_assoc_to_csdev(struct coresight_device *csdev);
-extern void cti_remove_assoc_from_csdev(struct coresight_device *csdev);
+struct cti_assoc_op {
+	void (*add)(struct coresight_device *csdev);
+	void (*remove)(struct coresight_device *csdev);
+};
 
-#else
-static inline void cti_add_assoc_to_csdev(struct coresight_device *csdev) {}
-static inline void
-cti_remove_assoc_from_csdev(struct coresight_device *csdev) {}
-#endif
+extern void coresight_set_cti_ops(const struct cti_assoc_op *cti_op);
+extern void coresight_remove_cti_ops(void);
 
 /*
  * Macros and inline functions to handle CoreSight UCI data and driver

drivers/hwtracing/coresight/coresight.c

@@ -56,6 +56,20 @@ static struct list_head *stm_path;
 const u32 coresight_barrier_pkt[4] = {0x7fffffff, 0x7fffffff, 0x7fffffff, 0x7fffffff};
 EXPORT_SYMBOL_GPL(coresight_barrier_pkt);
 
+static const struct cti_assoc_op *cti_assoc_ops;
+
+void coresight_set_cti_ops(const struct cti_assoc_op *cti_op)
+{
+	cti_assoc_ops = cti_op;
+}
+EXPORT_SYMBOL_GPL(coresight_set_cti_ops);
+
+void coresight_remove_cti_ops(void)
+{
+	cti_assoc_ops = NULL;
+}
+EXPORT_SYMBOL_GPL(coresight_remove_cti_ops);
+
 static int coresight_id_match(struct device *dev, void *data)
 {
 	int trace_id, i_trace_id;
@@ -1232,7 +1246,8 @@ static void coresight_device_release(struct device *dev)
 {
 	struct coresight_device *csdev = to_coresight_device(dev);
 
-	cti_remove_assoc_from_csdev(csdev);
+	if (cti_assoc_ops && cti_assoc_ops->remove)
+		cti_assoc_ops->remove(csdev);
 	fwnode_handle_put(csdev->dev.fwnode);
 	kfree(csdev->refcnt);
 	kfree(csdev);
@@ -1543,8 +1558,8 @@ struct coresight_device *coresight_register(struct coresight_desc *desc)
 		ret = coresight_fixup_device_conns(csdev);
 	if (!ret)
 		ret = coresight_fixup_orphan_conns(csdev);
-	if (!ret)
-		cti_add_assoc_to_csdev(csdev);
+	if (!ret && cti_assoc_ops && cti_assoc_ops->add)
+		cti_assoc_ops->add(csdev);
 
 	mutex_unlock(&coresight_mutex);
 	if (ret) {