diff options
| -rw-r--r-- | drivers/hwtracing/coresight/coresight.c | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c index 5e8880ca8078..07382c55b31d 100644 --- a/drivers/hwtracing/coresight/coresight.c +++ b/drivers/hwtracing/coresight/coresight.c @@ -132,12 +132,14 @@ static int coresight_enable_sink(struct coresight_device *csdev, u32 mode) { int ret; - if (!csdev->enable) { - if (sink_ops(csdev)->enable) { - ret = sink_ops(csdev)->enable(csdev, mode); - if (ret) - return ret; - } + /* + * We need to make sure the "new" session is compatible with the + * existing "mode" of operation. + */ + if (sink_ops(csdev)->enable) { + ret = sink_ops(csdev)->enable(csdev, mode); + if (ret) + return ret; csdev->enable = true; } @@ -339,8 +341,14 @@ int coresight_enable_path(struct list_head *path, u32 mode) switch (type) { case CORESIGHT_DEV_TYPE_SINK: ret = coresight_enable_sink(csdev, mode); + /* + * Sink is the first component turned on. If we + * failed to enable the sink, there are no components + * that need disabling. Disabling the path here + * would mean we could disrupt an existing session. + */ if (ret) - goto err; + goto out; break; case CORESIGHT_DEV_TYPE_SOURCE: /* sources are enabled from either sysFS or Perf */ |