From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750890AbdALWvq (ORCPT ); Thu, 12 Jan 2017 17:51:46 -0500 Received: from mail-pf0-f195.google.com ([209.85.192.195]:34121 "EHLO mail-pf0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750794AbdALWvp (ORCPT ); Thu, 12 Jan 2017 17:51:45 -0500 Subject: Re: [PATCH net-next v2 05/10] drivers: base: Add device_find_class() To: David Miller References: <20170112034121.27697-1-f.fainelli@gmail.com> <20170112034121.27697-6-f.fainelli@gmail.com> <20170112.162135.441956368122992032.davem@davemloft.net> Cc: netdev@vger.kernel.org, jason@lakedaemon.net, andrew@lunn.ch, sebastian.hesselbarth@gmail.com, gregory.clement@free-electrons.com, linux@armlinux.org.uk, vivien.didelot@savoirfairelinux.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org From: Florian Fainelli Message-ID: <81f5965c-3484-92d9-5c04-94c5b73735d0@gmail.com> Date: Thu, 12 Jan 2017 14:50:39 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: <20170112.162135.441956368122992032.davem@davemloft.net> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/12/2017 01:21 PM, David Miller wrote: > From: Florian Fainelli > Date: Wed, 11 Jan 2017 19:41:16 -0800 > >> Add a helper function to lookup a device reference given a class name. >> This is a preliminary patch to remove adhoc code from net/dsa/dsa.c and >> make it more generic. >> >> Signed-off-by: Florian Fainelli >> --- >> drivers/base/core.c | 19 +++++++++++++++++++ >> include/linux/device.h | 1 + >> 2 files changed, 20 insertions(+) >> >> diff --git a/drivers/base/core.c b/drivers/base/core.c >> index 020ea7f05520..3dd6047c10d8 100644 >> --- a/drivers/base/core.c >> +++ b/drivers/base/core.c >> @@ -2065,6 +2065,25 @@ struct device *device_find_child(struct device *parent, void *data, >> } >> EXPORT_SYMBOL_GPL(device_find_child); >> >> +static int dev_is_class(struct device *dev, void *class) > > I know you are just moving code, but this class argumnet is a string > and thus should be "char *" or even "const char *". Well, this is really so that we don't need to cast the arguments passed to device_find_child(), which takes a void *data as well. If we made that a const char *class, we'd get warnings that look like these: drivers/base/core.c: In function 'device_find_class': drivers/base/core.c:2083:2: warning: passing argument 2 of 'device_find_child' discards 'const' qualifier from pointer target type [enabled by default] return device_find_child(parent, class, dev_is_class); ^ drivers/base/core.c:2050:16: note: expected 'void *' but argument is of type 'const char *' struct device *device_find_child(struct device *parent, void *data, ^ drivers/base/core.c:2083:2: warning: passing argument 3 of 'device_find_child' from incompatible pointer type [enabled by default] return device_find_child(parent, class, dev_is_class); ^ drivers/base/core.c:2050:16: note: expected 'int (*)(struct device *, void *)' but argument is of type 'int (*)(struct device *, const char *)' struct device *device_find_child(struct device *parent, void *data, ^ -- Florian