From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mailout4.w1.samsung.com ([210.118.77.14]:43323 "EHLO mailout4.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751175Ab3FTGLX (ORCPT ); Thu, 20 Jun 2013 02:11:23 -0400 Received: from eucpsbgm2.samsung.com (unknown [203.254.199.245]) by mailout4.w1.samsung.com (Oracle Communications Messaging Server 7u4-24.01(7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0MOO00HTBH6QXI70@mailout4.w1.samsung.com> for linux-media@vger.kernel.org; Thu, 20 Jun 2013 07:11:20 +0100 (BST) Message-id: <51C29D05.6060304@samsung.com> Date: Thu, 20 Jun 2013 08:11:17 +0200 From: Andrzej Hajda MIME-version: 1.0 To: Laurent Pinchart Cc: linux-media@vger.kernel.org, Sylwester Nawrocki , Sakari Ailus , Kyungmin Park , hj210.choi@samsung.com, sw0312.kim@samsung.com Subject: Re: [PATCH RFC v3 1/3] media: added managed media entity initialization References: <1368692074-483-1-git-send-email-a.hajda@samsung.com> <2229025.9VJ8P9QgzO@avalon> <51C188E7.4020208@samsung.com> <3699560.VO8nIerPms@avalon> In-reply-to: <3699560.VO8nIerPms@avalon> Content-type: text/plain; charset=ISO-8859-1 Content-transfer-encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: On 06/19/2013 12:36 PM, Laurent Pinchart wrote: > Hi Andrzej, > > On Wednesday 19 June 2013 12:33:11 Andrzej Hajda wrote: >> On 06/19/2013 12:03 AM, Laurent Pinchart wrote: >>> On Thursday 16 May 2013 10:14:32 Andrzej Hajda wrote: >>>> This patch adds managed versions of initialization >>>> function for media entity. >>>> >>>> Signed-off-by: Andrzej Hajda >>>> Reviewed-by: Sylwester Nawrocki >>>> Signed-off-by: Kyungmin Park >>>> --- >>>> >>>> v3: >>>> - removed managed cleanup >>>> >>>> --- >>>> >>>> drivers/media/media-entity.c | 44 ++++++++++++++++++++++++++++++++++++ >>>> include/media/media-entity.h | 5 +++++ >>>> 2 files changed, 49 insertions(+) >>>> >>>> diff --git a/drivers/media/media-entity.c b/drivers/media/media-entity.c >>>> index e1cd132..b1e29a7 100644 >>>> --- a/drivers/media/media-entity.c >>>> +++ b/drivers/media/media-entity.c >>>> @@ -82,9 +82,53 @@ void >>>> media_entity_cleanup(struct media_entity *entity) >>>> { >>>> kfree(entity->links); >>>> + entity->links = NULL; >>>> } >>>> EXPORT_SYMBOL_GPL(media_entity_cleanup); >>>> >>>> +static void devm_media_entity_release(struct device *dev, void *res) >>>> +{ >>>> + struct media_entity **entity = res; >>>> + >>>> + media_entity_cleanup(*entity); >>>> +} >>>> + >>>> +/** >>>> + * devm_media_entity_init - managed media entity initialization >>>> + * >>>> + * @dev: Device for which @entity belongs to. >>>> + * @entity: Entity to be initialized. >>>> + * @num_pads: Total number of sink and source pads. >>>> + * @pads: Array of 'num_pads' pads. >>>> + * @extra_links: Initial estimate of the number of extra links. >>>> + * >>>> + * This is a managed version of media_entity_init. Entity initialized >>>> with >>>> + * this function will be automatically cleaned up on driver detach. >>>> + */ >>>> +int >>>> +devm_media_entity_init(struct device *dev, struct media_entity *entity, >>>> + u16 num_pads, struct media_pad *pads, u16 extra_links) >>> What kind of users do you see for this function ? Aren't subdev drivers >>> supposed to use the devm_* functions from patch 3/3 instead ? We should at >>> least make it clear in the documentation that drivers must not use both >>> devm_media_entity_init() and devm_v4l2_subdev_i2c_init(). >> It can be used for media entities which are not part of subdev. >> I will add statement about it. >> Besides subdev, for now only video_device uses media entity. >> I am not 100% sure about advantages of adding devm_media_entity_init - >> currently only 7 drivers in kernel uses video_device and >> media_entity_cleanup in those drivers is called not as straightforward >> as in subdevs. >> Replacing it with managed version would require deeper analysis :) > Thank you fhr the explanation. Maybe we should then delay introducing > devm_media_entity_init until needed ? > Yes, it can be delayed. Regards Andrzej