summaryrefslogtreecommitdiffstats
path: root/drivers
diff options
context:
space:
mode:
Diffstat (limited to 'drivers')
-rw-r--r--drivers/base/core.c19
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 316df6027093..21d4cb5d3767 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -1722,6 +1722,25 @@ static int fw_devlink_create_devlink(struct device *con,
struct device *sup_dev;
int ret = 0;
+ /*
+ * In some cases, a device P might also be a supplier to its child node
+ * C. However, this would defer the probe of C until the probe of P
+ * completes successfully. This is perfectly fine in the device driver
+ * model. device_add() doesn't guarantee probe completion of the device
+ * by the time it returns.
+ *
+ * However, there are a few drivers that assume C will finish probing
+ * as soon as it's added and before P finishes probing. So, we provide
+ * a flag to let fw_devlink know not to delay the probe of C until the
+ * probe of P completes successfully.
+ *
+ * When such a flag is set, we can't create device links where P is the
+ * supplier of C as that would delay the probe of C.
+ */
+ if (sup_handle->flags & FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD &&
+ fwnode_is_ancestor_of(sup_handle, con->fwnode))
+ return -EINVAL;
+
sup_dev = get_dev_from_fwnode(sup_handle);
if (sup_dev) {
/*