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| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2014-04-18 21:16:22 +0200 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2014-07-03 12:32:40 +0200 |
| commit | fcbcebce7159c928692dc6a5e88869f6e44438b9 (patch) | |
| tree | abc91266771d81fe0401da0febbaeba59dd425f8 | |
| parent | component: fix missed cleanup in case of devres failure (diff) | |
| download | linux-fcbcebce7159c928692dc6a5e88869f6e44438b9.tar.xz linux-fcbcebce7159c928692dc6a5e88869f6e44438b9.zip | |
component: ignore multiple additions of the same component
Permit masters to call component_master_add_child() and match the same
child multiple times. This may happen if there's multiple connections
to a single component device from other devices. In such scenarios,
we should not return a failure, but instead ignore the attempt.
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| -rw-r--r-- | drivers/base/component.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/base/component.c b/drivers/base/component.c index d0ebd4431736..55813e91bf0d 100644 --- a/drivers/base/component.c +++ b/drivers/base/component.c @@ -69,6 +69,11 @@ 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 +81,12 @@ 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; } |