diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h index 82e563cdc879..dfd24b85a577 100644 --- a/drivers/hwtracing/coresight/coresight-priv.h +++ b/drivers/hwtracing/coresight/coresight-priv.h @@ -147,7 +147,8 @@ static inline void coresight_write_reg_pair(void __iomem *addr, u64 val, void coresight_disable_path(struct list_head *path); int coresight_enable_path(struct list_head *path, u32 mode, void *sink_data); struct coresight_device *coresight_get_sink(struct list_head *path); -struct coresight_device *coresight_get_enabled_sink(bool reset); +struct coresight_device * +coresight_get_enabled_sink(struct coresight_device *source); struct coresight_device *coresight_get_sink_by_id(u32 id); struct list_head *coresight_build_path(struct coresight_device *csdev, struct coresight_device *sink); diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c index 0bbce0d29158..90ecd04a2f20 100644 --- a/drivers/hwtracing/coresight/coresight.c +++ b/drivers/hwtracing/coresight/coresight.c @@ -481,50 +481,46 @@ struct coresight_device *coresight_get_sink(struct list_head *path) return csdev; } -static int coresight_enabled_sink(struct device *dev, const void *data) +static struct coresight_device * +coresight_find_enabled_sink(struct coresight_device *csdev) { - const bool *reset = data; - struct coresight_device *csdev = to_coresight_device(dev); + int i; + struct coresight_device *sink; if ((csdev->type == CORESIGHT_DEV_TYPE_SINK || csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) && - csdev->activated) { - /* - * Now that we have a handle on the sink for this session, - * disable the sysFS "enable_sink" flag so that possible - * concurrent perf session that wish to use another sink don't - * trip on it. Doing so has no ramification for the current - * session. - */ - if (*reset) - csdev->activated = false; + csdev->activated) + return csdev; - return 1; + /* + * Recursively explore each port found on this element. + */ + for (i = 0; i < csdev->pdata->nr_outport; i++) { + struct coresight_device *child_dev; + + child_dev = csdev->pdata->conns[i].child_dev; + if (child_dev) + sink = coresight_find_enabled_sink(child_dev); + if (sink) + return sink; } - return 0; + return NULL; } /** - * coresight_get_enabled_sink - returns the first enabled sink found on the bus - * @deactivate: Whether the 'enable_sink' flag should be reset + * coresight_get_enabled_sink - returns the first enabled sink using + * connection based search starting from the source reference * - * When operated from perf the deactivate parameter should be set to 'true'. - * That way the "enabled_sink" flag of the sink that was selected can be reset, - * allowing for other concurrent perf sessions to choose a different sink. - * - * When operated from sysFS users have full control and as such the deactivate - * parameter should be set to 'false', hence mandating users to explicitly - * clear the flag. + * @source: Coresight source device reference */ -struct coresight_device *coresight_get_enabled_sink(bool deactivate) +struct coresight_device * +coresight_get_enabled_sink(struct coresight_device *source) { - struct device *dev = NULL; + if (!source) + return NULL; - dev = bus_find_device(&coresight_bustype, NULL, &deactivate, - coresight_enabled_sink); - - return dev ? to_coresight_device(dev) : NULL; + return coresight_find_enabled_sink(source); } static int coresight_sink_by_id(struct device *dev, const void *data) @@ -764,11 +760,7 @@ int coresight_enable(struct coresight_device *csdev) goto out; } - /* - * Search for a valid sink for this session but don't reset the - * "enable_sink" flag in sysFS. Users get to do that explicitly. - */ - sink = coresight_get_enabled_sink(false); + sink = coresight_get_enabled_sink(csdev); if (!sink) { ret = -EINVAL; goto out;