On 11/12/2025 06:10, Jie Gan wrote:
Retrieving the helper device of the specific coresight device based on its helper_subtype because a single coresight device may has multiple types of the helper devices.
Reviewed-by: Mike Leach mike.leach@linaro.org Signed-off-by: Jie Gan jie.gan@oss.qualcomm.com
drivers/hwtracing/coresight/coresight-core.c | 35 ++++++++++++++++++++++++++++ drivers/hwtracing/coresight/coresight-priv.h | 2 ++ 2 files changed, 37 insertions(+)
diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c index 0e8448784c62..667883ccb4b7 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -585,6 +585,41 @@ struct coresight_device *coresight_get_sink(struct coresight_path *path) } EXPORT_SYMBOL_GPL(coresight_get_sink); +/**
- coresight_get_helper: find the helper device of the assigned csdev.
- @csdev: The csdev the helper device is conntected to.
- @type: helper_subtype of the expected helper device.
- Retrieve the helper device for the specific csdev based on its
- helper_subtype.
- Return: the helper's csdev upon success or NULL for fail.
- */
+struct coresight_device *coresight_get_helper(struct coresight_device *csdev,
enum coresight_dev_subtype_helper subtype)
We have almost a similar function in coresight-core.c :
coresight_find_output_type(pdata, type, subtype).
Please could we reuse that, instead of adding similar funcitons ?
Please be careful about the mutex.
Suzuki
+{
- int i;
- struct coresight_device *helper;
- /* protect the connections */
- mutex_lock(&coresight_mutex);
- for (i = 0; i < csdev->pdata->nr_outconns; ++i) {
helper = csdev->pdata->out_conns[i]->dest_dev;if (!helper || !coresight_is_helper(helper))continue;if (helper->subtype.helper_subtype == subtype) {mutex_unlock(&coresight_mutex);return helper;}- }
- mutex_unlock(&coresight_mutex);
- return NULL;
+} +EXPORT_SYMBOL_GPL(coresight_get_helper);
- /**
- coresight_get_in_port: Find the input port number at @csdev where a @remote
- device is connected to.
diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h index cbf80b83e5ce..8e39a4dc7256 100644 --- a/drivers/hwtracing/coresight/coresight-priv.h +++ b/drivers/hwtracing/coresight/coresight-priv.h @@ -157,6 +157,8 @@ void coresight_path_assign_trace_id(struct coresight_path *path, enum cs_mode mode); int coresight_get_in_port(struct coresight_device *csdev, struct coresight_device *remote); +struct coresight_device *coresight_get_helper(struct coresight_device *csdev,
enum coresight_dev_subtype_helper subtype);#if IS_ENABLED(CONFIG_CORESIGHT_SOURCE_ETM3X) int etm_readl_cp14(u32 off, unsigned int *val);