Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756061AbYAOJKg (ORCPT ); Tue, 15 Jan 2008 04:10:36 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752448AbYAOJKV (ORCPT ); Tue, 15 Jan 2008 04:10:21 -0500 Received: from fg-out-1718.google.com ([72.14.220.157]:30645 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751912AbYAOJKS (ORCPT ); Tue, 15 Jan 2008 04:10:18 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version:content-type:content-disposition:in-reply-to:user-agent; b=lkZpubnwCWe2GAe7WnbuU3ljq2Fo5AUd/JJn01WGc0vNjhnHAo0Wj7Cc1D6CX3vdK137aBt4kdxwt+vWr3/hYzHHifjcaXGjyGLF13JPXnw36C4lmHOK9WdqnSZJgL1fOrjLhMZkTHJOK33sR3Bo8d8/Esw2Pv+VvTDZj81d4yo= Date: Tue, 15 Jan 2008 17:13:22 +0800 From: Dave Young To: Greg KH Cc: stefanr@s5r6.in-berlin.de, James.Bottomley@hansenpartnership.com, a.zummo@towertech.it, peterz@infradead.org, cbou@mail.ru, linux-kernel@vger.kernel.org, David Brownell , stern@rowland.harvard.edu, dwmw2@infradead.org, davem@davemloft.net, jarkao2@gmail.com, cornelia.huck@de.ibm.com Subject: Re: [PATCH 1/7] driver-core : add class iteration api Message-ID: <20080115091322.GA3186@darkstar.te-china.tietoenator.com> References: <20080112094754.GA2893@darkstar.te-china.tietoenator.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080112094754.GA2893@darkstar.te-china.tietoenator.com> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6474 Lines: 216 Add the following class iteration functions for driver use: class_for_each_device class_find_device class_for_each_child class_find_child Signed-off-by: Dave Young --- drivers/base/class.c | 159 +++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/device.h | 11 ++- 2 files changed, 168 insertions(+), 2 deletions(-) diff -upr linux/drivers/base/class.c linux.new/drivers/base/class.c --- linux/drivers/base/class.c 2008-01-15 11:12:29.000000000 +0800 +++ linux.new/drivers/base/class.c 2008-01-15 11:12:29.000000000 +0800 @@ -798,6 +798,165 @@ void class_device_put(struct class_devic kobject_put(&class_dev->kobj); } +/** + * class_for_each_device - device iterator + * @class: the class we're iterating + * @data: data for the callback + * @fn: function to be called for each device + * + * Iterate over @class's list of devices, and call @fn for each, + * passing it @data. + * + * We check the return of @fn each time. If it returns anything + * other than 0, we break out and return that value. + */ +int class_for_each_device(struct class *class, void *data, + int (*fn)(struct device *, void *)) +{ + struct device *dev; + int error = 0; + + if (!class) + return -EINVAL; + down(&class->sem); + list_for_each_entry(dev, &class->devices, node) { + dev = get_device(dev); + if (dev) { + error = fn(dev, data); + put_device(dev); + } else + error = -ENODEV; + if (error) + break; + } + up(&class->sem); + + return error; +} +EXPORT_SYMBOL_GPL(class_for_each_device); + +/** + * class_find_device - device iterator for locating a particular device + * @class: the class we're iterating + * @data: data for the match function + * @match: function to check device + * + * This is similar to the class_for_each_dev() 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. + + * Note, you will need to drop the reference with put_device() after use. + */ +struct device *class_find_device(struct class *class, void *data, + int (*match)(struct device *, void *)) +{ + struct device *dev; + int found = 0; + + if (!class) + return NULL; + + down(&class->sem); + list_for_each_entry(dev, &class->devices, node) { + dev = get_device(dev); + if (dev) { + if (match(dev, data)) { + found = 1; + break; + } else + put_device(dev); + } else + break; + } + up(&class->sem); + + return found ? dev : NULL; +} +EXPORT_SYMBOL_GPL(class_find_device); + +/** + * class_for_each_child - class child iterator + * @class: the class we're iterating + * @data: data for the callback + * @fn: function to be called for each child of the class + * + * Iterate over @class's list of children, and call @fn for each, + * passing it @data. + * + * We check the return of @fn each time. If it returns anything + * other than 0, we break out and return that value. + */ +int class_for_each_child(struct class *class, void *data, + int (*fn)(struct class_device *, void *)) +{ + struct class_device *dev; + int error = 0; + + if (!class) + return -EINVAL; + down(&class->sem); + list_for_each_entry(dev, &class->children, node) { + dev = class_device_get(dev); + if (dev) { + error = fn(dev, data); + class_device_put(dev); + } else + error = -ENODEV; + if (error) + break; + } + up(&class->sem); + + return error; +} +EXPORT_SYMBOL_GPL(class_for_each_child); + +/** + * class_find_child - device iterator for locating a particular class_device + * @class: the class we're iterating + * @data: data for the match function + * @match: function to check class_device + * + * This is similar to the class_for_each_child() function above, but it + * returns a reference to a class_device that is 'found' for later use, as + * determined by the @match callback. + * + * The callback should return 0 if the class_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 class_devices. + + * Note, you will need to drop the reference with class_device_put() after use. + */ +struct class_device *class_find_child(struct class *class, void *data, + int (*match)(struct class_device *, void *)) +{ + struct class_device *dev; + int found = 0; + + if (!class) + return NULL; + + down(&class->sem); + list_for_each_entry(dev, &class->children, node) { + dev = class_device_get(dev); + if (dev) { + if (match(dev, data)) { + found = 1; + break; + } else + class_device_put(dev); + } else + break; + } + up(&class->sem); + + return found ? dev : NULL; +} +EXPORT_SYMBOL_GPL(class_find_child); int class_interface_register(struct class_interface *class_intf) { diff -upr linux/include/linux/device.h linux.new/include/linux/device.h --- linux/include/linux/device.h 2008-01-15 11:12:29.000000000 +0800 +++ linux.new/include/linux/device.h 2008-01-15 11:12:29.000000000 +0800 @@ -180,8 +180,7 @@ struct class { struct list_head devices; struct list_head interfaces; struct kset class_dirs; - struct semaphore sem; /* locks both the children and interfaces lists */ - + struct semaphore sem; /* locks children, devices, interfaces */ struct class_attribute * class_attrs; struct class_device_attribute * class_dev_attrs; struct device_attribute * dev_attrs; @@ -199,6 +198,14 @@ struct class { extern int __must_check class_register(struct class *); extern void class_unregister(struct class *); +extern int class_for_each_device(struct class *class, void *data, + int (*fn)(struct device *dev, void *data)); +extern struct device *class_find_device(struct class *class, void *data, + int (*match)(struct device *, void *)); +extern int class_for_each_child(struct class *class, void *data, + int (*fn)(struct class_device *, void *)); +extern struct class_device *class_find_child(struct class *class, void *data, + int (*match)(struct class_device *, void *)); struct class_attribute { -- 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/