coresight: Add helpers registering/removing both AMBA and platform drivers

This adds two different helpers i.e coresight_init_driver()/remove_driver()
enabling coresight devices to register or remove AMBA and platform drivers.
This changes replicator and funnel devices to use above new helpers.

Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: James Clark <james.clark@arm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: coresight@lists.linaro.org
Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20240314055843.2625883-5-anshuman.khandual@arm.com

drivers/hwtracing/coresight/coresight-core.c

@@ -1398,6 +1398,35 @@ static void __exit coresight_exit(void)
 module_init(coresight_init);
 module_exit(coresight_exit);
 
+int coresight_init_driver(const char *drv, struct amba_driver *amba_drv,
+			  struct platform_driver *pdev_drv)
+{
+	int ret;
+
+	ret = amba_driver_register(amba_drv);
+	if (ret) {
+		pr_err("%s: error registering AMBA driver\n", drv);
+		return ret;
+	}
+
+	ret = platform_driver_register(pdev_drv);
+	if (!ret)
+		return 0;
+
+	pr_err("%s: error registering platform driver\n", drv);
+	amba_driver_unregister(amba_drv);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(coresight_init_driver);
+
+void coresight_remove_driver(struct amba_driver *amba_drv,
+			     struct platform_driver *pdev_drv)
+{
+	amba_driver_unregister(amba_drv);
+	platform_driver_unregister(pdev_drv);
+}
+EXPORT_SYMBOL_GPL(coresight_remove_driver);
+
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Pratik Patel <pratikp@codeaurora.org>");
 MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier@linaro.org>");

drivers/hwtracing/coresight/coresight-funnel.c

@@ -410,27 +410,12 @@ static struct amba_driver dynamic_funnel_driver = {
 
 static int __init funnel_init(void)
 {
-	int ret;
+	return coresight_init_driver("funnel", &dynamic_funnel_driver, &static_funnel_driver);
-
-	ret = platform_driver_register(&static_funnel_driver);
-	if (ret) {
-		pr_info("Error registering platform driver\n");
-		return ret;
-	}
-
-	ret = amba_driver_register(&dynamic_funnel_driver);
-	if (ret) {
-		pr_info("Error registering amba driver\n");
-		platform_driver_unregister(&static_funnel_driver);
-	}
-
-	return ret;
 }
 
 static void __exit funnel_exit(void)
 {
-	platform_driver_unregister(&static_funnel_driver);
+	coresight_remove_driver(&dynamic_funnel_driver, &static_funnel_driver);
-	amba_driver_unregister(&dynamic_funnel_driver);
 }
 
 module_init(funnel_init);

drivers/hwtracing/coresight/coresight-replicator.c

@@ -416,27 +416,13 @@ static struct amba_driver dynamic_replicator_driver = {
 
 static int __init replicator_init(void)
 {
-	int ret;
+	return coresight_init_driver("replicator", &dynamic_replicator_driver,
-
+				     &static_replicator_driver);
-	ret = platform_driver_register(&static_replicator_driver);
-	if (ret) {
-		pr_info("Error registering platform driver\n");
-		return ret;
-	}
-
-	ret = amba_driver_register(&dynamic_replicator_driver);
-	if (ret) {
-		pr_info("Error registering amba driver\n");
-		platform_driver_unregister(&static_replicator_driver);
-	}
-
-	return ret;
 }
 
 static void __exit replicator_exit(void)
 {
-	platform_driver_unregister(&static_replicator_driver);
+	coresight_remove_driver(&dynamic_replicator_driver, &static_replicator_driver);
-	amba_driver_unregister(&dynamic_replicator_driver);
 }
 
 module_init(replicator_init);

include/linux/coresight.h

@@ -12,6 +12,8 @@
 #include <linux/io.h>
 #include <linux/perf_event.h>
 #include <linux/sched.h>
+#include <linux/amba/bus.h>
+#include <linux/platform_device.h>
 
 /* Peripheral id registers (0xFD0-0xFEC) */
 #define CORESIGHT_PERIPHIDR4	0xfd0
@@ -658,4 +660,9 @@ coresight_find_output_type(struct coresight_platform_data *pdata,
 			   enum coresight_dev_type type,
 			   union coresight_dev_subtype subtype);
 
+int coresight_init_driver(const char *drv, struct amba_driver *amba_drv,
+			  struct platform_driver *pdev_drv);
+
+void coresight_remove_driver(struct amba_driver *amba_drv,
+			     struct platform_driver *pdev_drv);
 #endif		/* _LINUX_COREISGHT_H */