There are several places in the kernel where this kind of functionality is being used. Provide a generic helper for such cases. Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> --- drivers/base/core.c | 24 ++++++++++++++++++++++++ include/linux/device.h | 1 + 2 files changed, 25 insertions(+) diff --git a/drivers/base/core.c b/drivers/base/core.c index 7cd789c4985d..972bfe975cd0 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -3832,6 +3832,30 @@ struct device *device_find_child_by_name(struct device *parent, } EXPORT_SYMBOL_GPL(device_find_child_by_name); +/** + * device_find_first_child - device iterator for locating the fist child device. + * @parent: parent struct device + * + * This is similar to the device_find_child() function above, but it + * returns a reference to the first child device. + * + * NOTE: you will need to drop the reference with put_device() after use. + */ +struct device *device_find_first_child(struct device *parent) +{ + struct klist_iter i; + struct device *child; + + if (!parent) + return NULL; + + klist_iter_init(&parent->p->klist_children, &i); + child = get_device(next_device(&i)); + klist_iter_exit(&i); + return child; +} +EXPORT_SYMBOL_GPL(device_find_first_child); + int __init devices_init(void) { devices_kset = kset_create_and_add("devices", &device_uevent_ops, NULL); diff --git a/include/linux/device.h b/include/linux/device.h index dc941997795c..20171a4358df 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -905,6 +905,7 @@ struct device *device_find_child(struct device *dev, void *data, int (*match)(struct device *dev, void *data)); struct device *device_find_child_by_name(struct device *parent, const char *name); +struct device *device_find_first_child(struct device *parent); int device_rename(struct device *dev, const char *new_name); int device_move(struct device *dev, struct device *new_parent, enum dpm_order dpm_order); -- 2.35.1