device property: Add ETH_ALEN check, update comments.
[firefly-linux-kernel-4.4.55.git] / drivers / base / component.c
index c4778995cd728047d83a284d2e9248bbde89389f..f748430bb654154918ae67984405021835f44ec8 100644 (file)
 #include <linux/mutex.h>
 #include <linux/slab.h>
 
+struct component_match {
+       size_t alloc;
+       size_t num;
+       struct {
+               void *data;
+               int (*fn)(struct device *, void *);
+       } compare[0];
+};
+
 struct master {
        struct list_head node;
        struct list_head components;
@@ -25,6 +34,7 @@ struct master {
 
        const struct component_master_ops *ops;
        struct device *dev;
+       struct component_match *match;
 };
 
 struct component {
@@ -69,6 +79,11 @@ static void component_detach_master(struct master *master, struct component *c)
        c->master = NULL;
 }
 
+/*
+ * Add a component to a master, finding the component via the compare
+ * function and compare data.  This is safe to call for duplicate matches
+ * and will not result in the same component being added multiple times.
+ */
 int component_master_add_child(struct master *master,
        int (*compare)(struct device *, void *), void *compare_data)
 {
@@ -76,11 +91,12 @@ int component_master_add_child(struct master *master,
        int ret = -ENXIO;
 
        list_for_each_entry(c, &component_list, node) {
-               if (c->master)
+               if (c->master && c->master != master)
                        continue;
 
                if (compare(c->dev, compare_data)) {
-                       component_attach_master(master, c);
+                       if (!c->master)
+                               component_attach_master(master, c);
                        ret = 0;
                        break;
                }
@@ -90,6 +106,34 @@ int component_master_add_child(struct master *master,
 }
 EXPORT_SYMBOL_GPL(component_master_add_child);
 
+static int find_components(struct master *master)
+{
+       struct component_match *match = master->match;
+       size_t i;
+       int ret = 0;
+
+       if (!match) {
+               /*
+                * Search the list of components, looking for components that
+                * belong to this master, and attach them to the master.
+                */
+               return master->ops->add_components(master->dev, master);
+       }
+
+       /*
+        * Scan the array of match functions and attach
+        * any components which are found to this master.
+        */
+       for (i = 0; i < match->num; i++) {
+               ret = component_master_add_child(master,
+                                                match->compare[i].fn,
+                                                match->compare[i].data);
+               if (ret)
+                       break;
+       }
+       return ret;
+}
+
 /* Detach all attached components from this master */
 static void master_remove_components(struct master *master)
 {
@@ -113,44 +157,44 @@ static void master_remove_components(struct master *master)
 static int try_to_bring_up_master(struct master *master,
        struct component *component)
 {
-       int ret = 0;
+       int ret;
 
-       if (!master->bound) {
-               /*
-                * Search the list of components, looking for components that
-                * belong to this master, and attach them to the master.
-                */
-               if (master->ops->add_components(master->dev, master)) {
-                       /* Failed to find all components */
-                       master_remove_components(master);
-                       ret = 0;
-                       goto out;
-               }
+       if (master->bound)
+               return 0;
 
-               if (component && component->master != master) {
-                       master_remove_components(master);
-                       ret = 0;
-                       goto out;
-               }
+       /*
+        * Search the list of components, looking for components that
+        * belong to this master, and attach them to the master.
+        */
+       if (find_components(master)) {
+               /* Failed to find all components */
+               ret = 0;
+               goto out;
+       }
 
-               if (!devres_open_group(master->dev, NULL, GFP_KERNEL)) {
-                       ret = -ENOMEM;
-                       goto out;
-               }
+       if (component && component->master != master) {
+               ret = 0;
+               goto out;
+       }
 
-               /* Found all components */
-               ret = master->ops->bind(master->dev);
-               if (ret < 0) {
-                       devres_release_group(master->dev, NULL);
-                       dev_info(master->dev, "master bind failed: %d\n", ret);
-                       master_remove_components(master);
-                       goto out;
-               }
+       if (!devres_open_group(master->dev, NULL, GFP_KERNEL)) {
+               ret = -ENOMEM;
+               goto out;
+       }
 
-               master->bound = true;
-               ret = 1;
+       /* Found all components */
+       ret = master->ops->bind(master->dev);
+       if (ret < 0) {
+               devres_release_group(master->dev, NULL);
+               dev_info(master->dev, "master bind failed: %d\n", ret);
+               goto out;
        }
+
+       master->bound = true;
+       return 1;
+
 out:
+       master_remove_components(master);
 
        return ret;
 }
@@ -180,18 +224,89 @@ static void take_down_master(struct master *master)
        master_remove_components(master);
 }
 
-int component_master_add(struct device *dev,
-       const struct component_master_ops *ops)
+static size_t component_match_size(size_t num)
+{
+       return offsetof(struct component_match, compare[num]);
+}
+
+static struct component_match *component_match_realloc(struct device *dev,
+       struct component_match *match, size_t num)
+{
+       struct component_match *new;
+
+       if (match && match->alloc == num)
+               return match;
+
+       new = devm_kmalloc(dev, component_match_size(num), GFP_KERNEL);
+       if (!new)
+               return ERR_PTR(-ENOMEM);
+
+       if (match) {
+               memcpy(new, match, component_match_size(min(match->num, num)));
+               devm_kfree(dev, match);
+       } else {
+               new->num = 0;
+       }
+
+       new->alloc = num;
+
+       return new;
+}
+
+/*
+ * Add a component to be matched.
+ *
+ * The match array is first created or extended if necessary.
+ */
+void component_match_add(struct device *dev, struct component_match **matchptr,
+       int (*compare)(struct device *, void *), void *compare_data)
+{
+       struct component_match *match = *matchptr;
+
+       if (IS_ERR(match))
+               return;
+
+       if (!match || match->num == match->alloc) {
+               size_t new_size = match ? match->alloc + 16 : 15;
+
+               match = component_match_realloc(dev, match, new_size);
+
+               *matchptr = match;
+
+               if (IS_ERR(match))
+                       return;
+       }
+
+       match->compare[match->num].fn = compare;
+       match->compare[match->num].data = compare_data;
+       match->num++;
+}
+EXPORT_SYMBOL(component_match_add);
+
+int component_master_add_with_match(struct device *dev,
+       const struct component_master_ops *ops,
+       struct component_match *match)
 {
        struct master *master;
        int ret;
 
+       if (ops->add_components && match)
+               return -EINVAL;
+
+       if (match) {
+               /* Reallocate the match array for its true size */
+               match = component_match_realloc(dev, match, match->num);
+               if (IS_ERR(match))
+                       return PTR_ERR(match);
+       }
+
        master = kzalloc(sizeof(*master), GFP_KERNEL);
        if (!master)
                return -ENOMEM;
 
        master->dev = dev;
        master->ops = ops;
+       master->match = match;
        INIT_LIST_HEAD(&master->components);
 
        /* Add to the list of available masters. */
@@ -209,6 +324,13 @@ int component_master_add(struct device *dev,
 
        return ret < 0 ? ret : 0;
 }
+EXPORT_SYMBOL_GPL(component_master_add_with_match);
+
+int component_master_add(struct device *dev,
+       const struct component_master_ops *ops)
+{
+       return component_master_add_with_match(dev, ops, NULL);
+}
 EXPORT_SYMBOL_GPL(component_master_add);
 
 void component_master_del(struct device *dev,