diff options
Diffstat (limited to 'drivers/base/component.c')
| -rw-r--r-- | drivers/base/component.c | 192 |
1 files changed, 157 insertions, 35 deletions
diff --git a/drivers/base/component.c b/drivers/base/component.c index c4778995cd72..f748430bb654 100644 --- a/drivers/base/component.c +++ b/drivers/base/component.c @@ -18,6 +18,15 @@ #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, |