driver-core: platform: Provide helpers for multi-driver modules
Some modules register several sub-drivers. Provide a helper that makes
it easy to register and unregister a list of sub-drivers, as well as
unwind properly on error.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/Documentation/driver-model/platform.txt b/Documentation/driver-model/platform.txt
index 07795ec..e456696 100644
--- a/Documentation/driver-model/platform.txt
+++ b/Documentation/driver-model/platform.txt
@@ -63,6 +63,20 @@
int platform_driver_probe(struct platform_driver *drv,
int (*probe)(struct platform_device *))
+Kernel modules can be composed of several platform drivers. The platform core
+provides helpers to register and unregister an array of drivers:
+
+ int __platform_register_drivers(struct platform_driver * const *drivers,
+ unsigned int count, struct module *owner);
+ void platform_unregister_drivers(struct platform_driver * const *drivers,
+ unsigned int count);
+
+If one of the drivers fails to register, all drivers registered up to that
+point will be unregistered in reverse order. Note that there is a convenience
+macro that passes THIS_MODULE as owner parameter:
+
+ #define platform_register_driver(drivers, count)
+
Device Enumeration
~~~~~~~~~~~~~~~~~~