driver core: Add device_link_remove function

Device_link_remove uses the same arguments than device_link_add. The Goal
is to avoid storing the link pointer.

Signed-off-by: pascal paillet <p.paillet@st.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 36622b5..3b380b1 100644 (file)
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -365,6 +365,36 @@ void device_link_del(struct device_link *link)
 }
 EXPORT_SYMBOL_GPL(device_link_del);
 
+/**
+ * device_link_remove - remove a link between two devices.
+ * @consumer: Consumer end of the link.
+ * @supplier: Supplier end of the link.
+ *
+ * The caller must ensure proper synchronization of this function with runtime
+ * PM.
+ */
+void device_link_remove(void *consumer, struct device *supplier)
+{
+       struct device_link *link;
+
+       if (WARN_ON(consumer == supplier))
+               return;
+
+       device_links_write_lock();
+       device_pm_lock();
+
+       list_for_each_entry(link, &supplier->links.consumers, s_node) {
+               if (link->consumer == consumer) {
+                       kref_put(&link->kref, __device_link_del);
+                       break;
+               }
+       }
+
+       device_pm_unlock();
+       device_links_write_unlock();
+}
+EXPORT_SYMBOL_GPL(device_link_remove);
+
 static void device_links_missing_supplier(struct device *dev)
 {
        struct device_link *link;

diff --git a/include/linux/device.h b/include/linux/device.h
index 055a69d..9c1c3b1 100644 (file)
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -1316,6 +1316,7 @@ extern const char *dev_driver_string(const struct device *dev);
 struct device_link *device_link_add(struct device *consumer,
                                    struct device *supplier, u32 flags);
 void device_link_del(struct device_link *link);
+void device_link_remove(void *consumer, struct device *supplier);
 
 #ifdef CONFIG_PRINTK