@@ -490,6 +490,16 @@ void device_links_driver_cleanup(struct device *dev)
WARN_ON(link->flags & DL_FLAG_AUTOREMOVE);
WARN_ON(link->status != DL_STATE_SUPPLIER_UNBIND);
+
+ /*
+ * autoremove the links between this @dev and its consumer
+ * devices that are not active, i.e. where the link state
+ * has moved to DL_STATE_SUPPLIER_UNBIND.
+ */
+ if (link->status == DL_STATE_SUPPLIER_UNBIND &&
+ link->flags & DL_FLAG_AUTOREMOVE_S)
+ kref_put(&link->kref, __device_link_del);
+
WRITE_ONCE(link->status, DL_STATE_DORMANT);
}
@@ -779,11 +779,13 @@ enum device_link_state {
* AUTOREMOVE: Remove this link automatically on consumer driver unbind.
* PM_RUNTIME: If set, the runtime PM framework will use this link.
* RPM_ACTIVE: Run pm_runtime_get_sync() on the supplier during link creation.
+ * AUTOREMOVE_S: Remove this link automatically on supplier driver unbind.
*/
#define DL_FLAG_STATELESS BIT(0)
#define DL_FLAG_AUTOREMOVE BIT(1)
#define DL_FLAG_PM_RUNTIME BIT(2)
#define DL_FLAG_RPM_ACTIVE BIT(3)
+#define DL_FLAG_AUTOREMOVE_S BIT(4)
/**
* struct device_link - Device link representation.
When using the device links without the consumers or suppliers maintaining pointers to these links, a flag can help in autoremoving the links on supplier driver unbind. We remove these links only when the supplier's link to its consumers has gone in DL_STATE_SUPPLIER_UNBIND state. Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> Suggested-by: Lukas Wunner <lukas@wunner.de> --- Lukas, as suggested in the thread [1] this change adds additional flag to autoremove device links on supplier unbind. For arm-smmu, we want to _not_ keep references to the device links added between arm-smmu, and consumer devices. Robin also pointed to [2] the need to autoremove the device link on supplier unbind rather than consumer unbind. [1] https://lkml.org/lkml/2018/3/14/390 [2] https://lkml.org/lkml/2018/5/21/381 drivers/base/core.c | 10 ++++++++++ include/linux/device.h | 2 ++ 2 files changed, 12 insertions(+)