From patchwork Thu Feb 5 13:48:21 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Takashi Iwai X-Patchwork-Id: 5784721 Return-Path: X-Original-To: patchwork-alsa-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 207389F30C for ; Thu, 5 Feb 2015 13:48:55 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 4781D20279 for ; Thu, 5 Feb 2015 13:48:54 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) by mail.kernel.org (Postfix) with ESMTP id E0C7B2021F for ; Thu, 5 Feb 2015 13:48:52 +0000 (UTC) Received: by alsa0.perex.cz (Postfix, from userid 1000) id BB600264F36; Thu, 5 Feb 2015 14:48:51 +0100 (CET) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,NO_DNS_FOR_FROM, UNPARSEABLE_RELAY autolearn=no version=3.3.1 Received: from alsa0.perex.cz (localhost [IPv6:::1]) by alsa0.perex.cz (Postfix) with ESMTP id BDA30264F03; Thu, 5 Feb 2015 14:48:41 +0100 (CET) X-Original-To: alsa-devel@alsa-project.org Delivered-To: alsa-devel@alsa-project.org Received: by alsa0.perex.cz (Postfix, from userid 1000) id BAF04264F22; Thu, 5 Feb 2015 14:48:35 +0100 (CET) Received: from mx2.suse.de (cantor2.suse.de [195.135.220.15]) by alsa0.perex.cz (Postfix) with ESMTP id 4A988264F03 for ; Thu, 5 Feb 2015 14:48:27 +0100 (CET) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 33F2EAC78 for ; Thu, 5 Feb 2015 13:48:26 +0000 (UTC) From: Takashi Iwai To: alsa-devel@alsa-project.org Date: Thu, 5 Feb 2015 14:48:21 +0100 Message-Id: <1423144102-24801-1-git-send-email-tiwai@suse.de> X-Mailer: git-send-email 2.2.2 Subject: [alsa-devel] [PATCH 1/2] ALSA: Add a helper to add a new attribute group to card X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org X-Virus-Scanned: ClamAV using ClamSMTP For assigning sysfs entries for a card device from the driver, introduce a new helper function, snd_card_add_dev_attr(). In this way, we can avoid the possible race between the device registration and the sysfs addition / removal. The driver can pass a new attribute group to add freely. This has to be called before snd_card_register(). Currently, up to two extra groups can be added. More than that, it'll return an error. Signed-off-by: Takashi Iwai --- include/sound/core.h | 3 +++ sound/core/init.c | 31 +++++++++++++++++++++++++------ 2 files changed, 28 insertions(+), 6 deletions(-) diff --git a/include/sound/core.h b/include/sound/core.h index 58882bfacdd7..da5748289968 100644 --- a/include/sound/core.h +++ b/include/sound/core.h @@ -132,6 +132,7 @@ struct snd_card { struct completion *release_completion; struct device *dev; /* device assigned to this card */ struct device card_dev; /* cardX object for sysfs */ + const struct attribute_group *dev_groups[4]; /* assigned sysfs attr */ bool registered; /* card_dev is registered? */ #ifdef CONFIG_PM @@ -262,6 +263,8 @@ void snd_card_set_id(struct snd_card *card, const char *id); int snd_card_register(struct snd_card *card); int snd_card_info_init(void); int snd_card_info_done(void); +int snd_card_add_dev_attr(struct snd_card *card, + const struct attribute_group *group); int snd_component_add(struct snd_card *card, const char *component); int snd_card_file_add(struct snd_card *card, struct file *file); int snd_card_file_remove(struct snd_card *card, struct file *file); diff --git a/sound/core/init.c b/sound/core/init.c index 96194599e82e..35419054821c 100644 --- a/sound/core/init.c +++ b/sound/core/init.c @@ -181,7 +181,7 @@ void snd_device_initialize(struct device *dev, struct snd_card *card) EXPORT_SYMBOL_GPL(snd_device_initialize); static int snd_card_do_free(struct snd_card *card); -static const struct attribute_group *card_dev_attr_groups[]; +static const struct attribute_group card_dev_attr_group; static void release_card_device(struct device *dev) { @@ -269,7 +269,8 @@ int snd_card_new(struct device *parent, int idx, const char *xid, card->card_dev.parent = parent; card->card_dev.class = sound_class; card->card_dev.release = release_card_device; - card->card_dev.groups = card_dev_attr_groups; + card->card_dev.groups = card->dev_groups; + card->dev_groups[0] = &card_dev_attr_group; err = kobject_set_name(&card->card_dev.kobj, "card%d", idx); if (err < 0) goto __error; @@ -700,14 +701,32 @@ static struct attribute *card_dev_attrs[] = { NULL }; -static struct attribute_group card_dev_attr_group = { +static const struct attribute_group card_dev_attr_group = { .attrs = card_dev_attrs, }; -static const struct attribute_group *card_dev_attr_groups[] = { - &card_dev_attr_group, - NULL +/** + * snd_card_add_dev_attr - Append a new sysfs attribute group to card + * @card: card instance + * @group: attribute group to append + */ +int snd_card_add_dev_attr(struct snd_card *card, + const struct attribute_group *group) +{ + int i; + + /* loop for (arraysize-1) here to keep NULL at the last entry */ + for (i = 0; i < ARRAY_SIZE(card->dev_groups) - 1; i++) { + if (!card->dev_groups[i]) { + card->dev_groups[i] = group; + return 0; + } + } + + dev_err(card->dev, "Too many groups assigned\n"); + return -ENOSPC; }; +EXPORT_SYMBOL_GPL(snd_card_add_dev_attr); /** * snd_card_register - register the soundcard