From: Leo Yan <leo.yan@arm.com>
Date: Mon, 9 Feb 2026 12:44:38 +0000 (+0000)
Subject: coresight: Move sink validation into etm_perf_add_symlink_sink()
X-Git-Tag: v7.1-rc1~17^2^2~18
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=6b1ffc542850e5dd1c71394f6205582a9c8ad9c8;p=thirdparty%2Fkernel%2Flinux.git

coresight: Move sink validation into etm_perf_add_symlink_sink()

Move the sink device type checks into etm_perf_add_symlink_sink(), and
return -EOPNOTSUPP for unsupported devices.  This simplifies the
registration flow to invoke etm_perf_add_symlink_sink() unconditionally.

Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Leo Yan <leo.yan@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20260209-arm_coresight_refactor_dev_register-v4-6-62d6042f76f7@arm.com
---

diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c
index 34439ca98d8d..6ddbc773330e 100644
--- a/drivers/hwtracing/coresight/coresight-core.c
+++ b/drivers/hwtracing/coresight/coresight-core.c
@@ -1383,21 +1383,16 @@ struct coresight_device *coresight_register(struct coresight_desc *desc)
 		goto out_unlock;
 	}
 
-	if ((csdev->type == CORESIGHT_DEV_TYPE_SINK ||
-	     csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) &&
-	    sink_ops(csdev)->alloc_buffer) {
-		ret = etm_perf_add_symlink_sink(csdev);
+	ret = etm_perf_add_symlink_sink(csdev);
 
-		if (ret) {
-			device_unregister(&csdev->dev);
-			/*
-			 * As with the above, all resources are free'd
-			 * explicitly via coresight_device_release() triggered
-			 * from put_device(), which is in turn called from
-			 * function device_unregister().
-			 */
-			goto out_unlock;
-		}
+	/*
+	 * As with the above, all resources are free'd explicitly via
+	 * coresight_device_release() triggered from put_device(), which is in
+	 * turn called from function device_unregister().
+	 */
+	if (ret && ret != -EOPNOTSUPP) {
+		device_unregister(&csdev->dev);
+		goto out_unlock;
 	}
 	/* Device is now registered */
 	registered = true;
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 72017dcc3b7f..f85dedf89a3f 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -902,7 +902,10 @@ int etm_perf_add_symlink_sink(struct coresight_device *csdev)
 
 	if (csdev->type != CORESIGHT_DEV_TYPE_SINK &&
 	    csdev->type != CORESIGHT_DEV_TYPE_LINKSINK)
-		return -EINVAL;
+		return -EOPNOTSUPP;
+
+	if (!sink_ops(csdev)->alloc_buffer)
+		return -EOPNOTSUPP;
 
 	if (csdev->ea != NULL)
 		return -EINVAL;