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-rw-r--r--drivers/base/core.c74
1 files changed, 66 insertions, 8 deletions
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 8611385e44b5..d58ea075f807 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -300,17 +300,26 @@ struct device_link *device_link_add(struct device *consumer,
link->status = DL_STATE_NONE;
} else {
switch (supplier->links.status) {
- case DL_DEV_DRIVER_BOUND:
+ case DL_DEV_PROBING:
switch (consumer->links.status) {
case DL_DEV_PROBING:
/*
- * Some callers expect the link creation during
- * consumer driver probe to resume the supplier
- * even without DL_FLAG_RPM_ACTIVE.
+ * A consumer driver can create a link to a
+ * supplier that has not completed its probing
+ * yet as long as it knows that the supplier is
+ * already functional (for example, it has just
+ * acquired some resources from the supplier).
*/
- if (flags & DL_FLAG_PM_RUNTIME)
- pm_runtime_resume(supplier);
-
+ link->status = DL_STATE_CONSUMER_PROBE;
+ break;
+ default:
+ link->status = DL_STATE_DORMANT;
+ break;
+ }
+ break;
+ case DL_DEV_DRIVER_BOUND:
+ switch (consumer->links.status) {
+ case DL_DEV_PROBING:
link->status = DL_STATE_CONSUMER_PROBE;
break;
case DL_DEV_DRIVER_BOUND:
@@ -331,6 +340,14 @@ struct device_link *device_link_add(struct device *consumer,
}
/*
+ * Some callers expect the link creation during consumer driver probe to
+ * resume the supplier even without DL_FLAG_RPM_ACTIVE.
+ */
+ if (link->status == DL_STATE_CONSUMER_PROBE &&
+ flags & DL_FLAG_PM_RUNTIME)
+ pm_runtime_resume(supplier);
+
+ /*
* Move the consumer and all of the devices depending on it to the end
* of dpm_list and the devices_kset list.
*
@@ -518,6 +535,16 @@ void device_links_driver_bound(struct device *dev)
if (link->flags & DL_FLAG_STATELESS)
continue;
+ /*
+ * Links created during consumer probe may be in the "consumer
+ * probe" state to start with if the supplier is still probing
+ * when they are created and they may become "active" if the
+ * consumer probe returns first. Skip them here.
+ */
+ if (link->status == DL_STATE_CONSUMER_PROBE ||
+ link->status == DL_STATE_ACTIVE)
+ continue;
+
WARN_ON(link->status != DL_STATE_DORMANT);
WRITE_ONCE(link->status, DL_STATE_AVAILABLE);
}
@@ -557,17 +584,48 @@ static void __device_links_no_driver(struct device *dev)
if (link->flags & DL_FLAG_AUTOREMOVE_CONSUMER)
__device_link_del(&link->kref);
- else if (link->status != DL_STATE_SUPPLIER_UNBIND)
+ else if (link->status == DL_STATE_CONSUMER_PROBE ||
+ link->status == DL_STATE_ACTIVE)
WRITE_ONCE(link->status, DL_STATE_AVAILABLE);
}
dev->links.status = DL_DEV_NO_DRIVER;
}
+/**
+ * device_links_no_driver - Update links after failing driver probe.
+ * @dev: Device whose driver has just failed to probe.
+ *
+ * Clean up leftover links to consumers for @dev and invoke
+ * %__device_links_no_driver() to update links to suppliers for it as
+ * appropriate.
+ *
+ * Links with the DL_FLAG_STATELESS flag set are ignored.
+ */
void device_links_no_driver(struct device *dev)
{
+ struct device_link *link;
+
device_links_write_lock();
+
+ list_for_each_entry(link, &dev->links.consumers, s_node) {
+ if (link->flags & DL_FLAG_STATELESS)
+ continue;
+
+ /*
+ * The probe has failed, so if the status of the link is
+ * "consumer probe" or "active", it must have been added by
+ * a probing consumer while this device was still probing.
+ * Change its state to "dormant", as it represents a valid
+ * relationship, but it is not functionally meaningful.
+ */
+ if (link->status == DL_STATE_CONSUMER_PROBE ||
+ link->status == DL_STATE_ACTIVE)
+ WRITE_ONCE(link->status, DL_STATE_DORMANT);
+ }
+
__device_links_no_driver(dev);
+
device_links_write_unlock();
}