coresight: cti: Fix bug clearing sysfs links on callback

During module unload, a coresight driver module will call back into
the CTI driver to remove any links between the two devices.

The current code has 2 issues:-
1) in the CTI driver the matching code is matching to the wrong device
so misses all the links.
2) The callback is called too late in the unload process resulting in a
crash.

This fixes both the issues.

Fixes: 177af828 ("coresight: cti: Enable CTI associated with devices")
Reported-by: Tingwei Zhang <tingwei@codeaurora.org>
Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-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/20200928163513.70169-19-mathieu.poirier@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/hwtracing/coresight/coresight-cti.c

@@ -591,7 +591,7 @@ static void cti_remove_assoc_from_csdev(struct coresight_device *csdev)
 		ctidrv = csdev_to_cti_drvdata(csdev->ect_dev);
 		ctidev = &ctidrv->ctidev;
 		list_for_each_entry(tc, &ctidev->trig_cons, node) {
-			if (tc->con_dev == csdev->ect_dev) {
+			if (tc->con_dev == csdev) {
 				cti_remove_sysfs_link(ctidrv, tc);
 				tc->con_dev = NULL;
 				break;

drivers/hwtracing/coresight/coresight.c

@@ -1246,8 +1246,6 @@ static void coresight_device_release(struct device *dev)
 {
 	struct coresight_device *csdev = to_coresight_device(dev);
 
-	if (cti_assoc_ops && cti_assoc_ops->remove)
-		cti_assoc_ops->remove(csdev);
 	fwnode_handle_put(csdev->dev.fwnode);
 	kfree(csdev->refcnt);
 	kfree(csdev);
@@ -1582,6 +1580,8 @@ void coresight_unregister(struct coresight_device *csdev)
 {
 	etm_perf_del_symlink_sink(csdev);
 	/* Remove references of that device in the topology */
+	if (cti_assoc_ops && cti_assoc_ops->remove)
+		cti_assoc_ops->remove(csdev);
 	coresight_remove_conns(csdev);
 	coresight_clear_default_sink(csdev);
 	coresight_release_platform_data(csdev, csdev->pdata);