Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754146AbWKGPzR (ORCPT ); Tue, 7 Nov 2006 10:55:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754141AbWKGPzQ (ORCPT ); Tue, 7 Nov 2006 10:55:16 -0500 Received: from mtagate4.de.ibm.com ([195.212.29.153]:29451 "EHLO mtagate4.de.ibm.com") by vger.kernel.org with ESMTP id S1754146AbWKGPzO (ORCPT ); Tue, 7 Nov 2006 10:55:14 -0500 Date: Tue, 7 Nov 2006 16:55:39 +0100 From: Cornelia Huck To: linux-kernel Subject: [RFC/Patch 1/5] driver core: Introduce device_find_child(). Message-ID: <20061107165539.66936266@gondolin.boeblingen.de.ibm.com> In-Reply-To: <20061107163730.0c8f3dad@gondolin.boeblingen.de.ibm.com> References: <20061107163730.0c8f3dad@gondolin.boeblingen.de.ibm.com> X-Mailer: Sylpheed-Claws 2.5.6 (GTK+ 2.8.20; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2429 Lines: 74 From: Cornelia Huck Introduce device_find_child() to match device_for_each_child(). Signed-off-by: Cornelia Huck --- drivers/base/core.c | 32 ++++++++++++++++++++++++++++++++ include/linux/device.h | 2 ++ 2 files changed, 34 insertions(+) --- linux-2.6-CH.orig/drivers/base/core.c +++ linux-2.6-CH/drivers/base/core.c @@ -749,12 +749,44 @@ int device_for_each_child(struct device return error; } +/** + * device_find_child - device iterator for locating a particular device. + * @parent: parent struct device + * @data: Data to pass to match function + * @match: Callback function to check device + * + * This is similar to the device_for_each_child() function above, but it + * returns a reference to a device that is 'found' for later use, as + * determined by the @match callback. + * + * The callback should return 0 if the device doesn't match and non-zero + * if it does. If the callback returns non-zero, this function will + * return to the caller and not iterate over any more devices. + */ +struct device * device_find_child(struct device *parent, void *data, + int (*match)(struct device *, void *)) +{ + struct klist_iter i; + struct device *child; + + if (!parent) + return NULL; + + klist_iter_init(&parent->klist_children, &i); + while ((child = next_device(&i))) + if (match(child, data) && get_device(child)) + break; + klist_iter_exit(&i); + return child; +} + int __init devices_init(void) { return subsystem_register(&devices_subsys); } EXPORT_SYMBOL_GPL(device_for_each_child); +EXPORT_SYMBOL_GPL(device_find_child); EXPORT_SYMBOL_GPL(device_initialize); EXPORT_SYMBOL_GPL(device_add); --- linux-2.6-CH.orig/include/linux/device.h +++ linux-2.6-CH/include/linux/device.h @@ -420,6 +420,8 @@ extern int __must_check device_add(struc extern void device_del(struct device * dev); extern int device_for_each_child(struct device *, void *, int (*fn)(struct device *, void *)); +extern struct device *device_find_child(struct device *, void *data, + int (*match)(struct device *, void *)); extern int device_rename(struct device *dev, char *new_name); /* - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/