On Fri, 25 Jul 2025 at 11:08, Jie Gan jie.gan@oss.qualcomm.com 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.
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 042c4fa39e55..018b1119c48a 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -580,6 +580,41 @@ 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,
int type)+{
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 == type) {mutex_unlock(&coresight_mutex);return helper;}}mutex_unlock(&coresight_mutex);return NULL;+} +EXPORT_SYMBOL_GPL(coresight_get_helper);
/**
- coresight_get_in_port_dest: get the in-port number of the dest device
- that is connected to the src device.
diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h index e51b22b8ebde..f80122827934 100644 --- a/drivers/hwtracing/coresight/coresight-priv.h +++ b/drivers/hwtracing/coresight/coresight-priv.h @@ -158,6 +158,8 @@ void coresight_path_assign_trace_id(struct coresight_path *path, enum cs_mode mode); int coresight_get_in_port_dest(struct coresight_device *src, struct coresight_device *dest); +struct coresight_device *coresight_get_helper(struct coresight_device *csdev,
int type);#if IS_ENABLED(CONFIG_CORESIGHT_SOURCE_ETM3X) int etm_readl_cp14(u32 off, unsigned int *val); -- 2.34.1
Reviewed-by: Mike Leach mike.leach@linaro.org