From patchwork Thu Feb 11 11:13:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jaroslav Kysela X-Patchwork-Id: 381888 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 854A8C433DB for ; Thu, 11 Feb 2021 11:16:19 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9A2E264DD5 for ; Thu, 11 Feb 2021 11:16:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9A2E264DD5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=perex.cz Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=alsa-devel-bounces@alsa-project.org Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id 2DCB0822; Thu, 11 Feb 2021 12:15:27 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 2DCB0822 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1613042177; bh=Op9QA6ATfKtfPcDWbXoGe/Jui444+KZ/CbmkfQhBRX8=; h=From:To:Subject:Date:In-Reply-To:References:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=b0MvFFbbGzVDiWkp+yXeL3Zwuv2ajx4wAxVU4r+SwwF9jxrizCkYBseao8kOANN6y 4zYpTWPwMbuym3Ol4dfEGpocBbaE9L0iDGPFSvG/f2Vu3oWC7sL1V4KQ8kge0+GmcC h5f5alX1bzRVcV9hO0bSxvMYquwsyyQZqc52xtMA= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 4E151F8027C; Thu, 11 Feb 2021 12:14:41 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 7908AF8010D; Thu, 11 Feb 2021 12:14:39 +0100 (CET) Received: from mail1.perex.cz (mail1.perex.cz [77.48.224.245]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id E121DF8010D for ; Thu, 11 Feb 2021 12:14:32 +0100 (CET) Received: from mail1.perex.cz (localhost [127.0.0.1]) by smtp1.perex.cz (Perex's E-mail Delivery System) with ESMTP id 89F44A0042; Thu, 11 Feb 2021 12:14:32 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.perex.cz 89F44A0042 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=perex.cz; s=default; t=1613042072; bh=fzYRDyHtpCyHrWbbk+cY3qghWRM/y9c5OBSt9v/OO2g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jCwMuQ874uBFOoroswfLa0qeTkF5awlfENfTBxSslFAp9CNvjkgsBrlwgJfxYdFnO BlFtclxHAHbN0mTZfGWwdtT3MCOoyEwcRfmtmvCYBzmnplg32Np/Pzm5JLXBWeuIHz vMGiyJ0sL/Q9P6ZQYWDTTn8GoKP9Hr2GK/OyEU9Q= Received: from p1gen2.perex-int.cz (unknown [192.168.100.98]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: perex) by mail1.perex.cz (Perex's E-mail Delivery System) with ESMTPSA; Thu, 11 Feb 2021 12:14:27 +0100 (CET) From: Jaroslav Kysela To: ALSA development Subject: [PATCH 2/5] ALSA: control - add layer registration routines Date: Thu, 11 Feb 2021 12:13:57 +0100 Message-Id: <20210211111400.1131020-3-perex@perex.cz> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210211111400.1131020-1-perex@perex.cz> References: <20210211111400.1131020-1-perex@perex.cz> MIME-Version: 1.0 Cc: Takashi Iwai , Hans de Goede , Perry Yuan X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 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: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" The layer registration allows to handle an extra functionality on top of the control API. It can be used for the audio LED control for example. Signed-off-by: Jaroslav Kysela --- include/sound/control.h | 12 +++++ sound/core/control.c | 104 +++++++++++++++++++++++++++++++++++++++- 2 files changed, 114 insertions(+), 2 deletions(-) diff --git a/include/sound/control.h b/include/sound/control.h index 22f3d48163ff..175610bfa8c8 100644 --- a/include/sound/control.h +++ b/include/sound/control.h @@ -108,6 +108,14 @@ struct snd_ctl_file { struct list_head events; /* waiting events for read */ }; +struct snd_ctl_layer_ops { + struct snd_ctl_layer_ops *next; + const char *module_name; + void (*lregister)(struct snd_card *card); + void (*ldisconnect)(struct snd_card *card); + void (*lnotify)(struct snd_card *card, unsigned int mask, struct snd_kcontrol *kctl, unsigned int ioff); +}; + #define snd_ctl_file(n) list_entry(n, struct snd_ctl_file, list) typedef int (*snd_kctl_ioctl_func_t) (struct snd_card * card, @@ -140,6 +148,10 @@ int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn); #define snd_ctl_unregister_ioctl_compat(fcn) #endif +int snd_ctl_request_layer(const char *module_name); +void snd_ctl_register_layer(struct snd_ctl_layer_ops *lops); +void snd_ctl_disconnect_layer(struct snd_ctl_layer_ops *lops); + int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type); static inline unsigned int snd_ctl_get_ioffnum(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id) diff --git a/sound/core/control.c b/sound/core/control.c index 8a5cedb0a4be..19aa19d8ff92 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -28,10 +28,12 @@ struct snd_kctl_ioctl { }; static DECLARE_RWSEM(snd_ioctl_rwsem); +static DECLARE_RWSEM(snd_ctl_layer_rwsem); static LIST_HEAD(snd_control_ioctls); #ifdef CONFIG_COMPAT static LIST_HEAD(snd_control_compat_ioctls); #endif +static struct snd_ctl_layer_ops *snd_ctl_layer; static int snd_ctl_open(struct inode *inode, struct file *file) { @@ -195,10 +197,15 @@ void snd_ctl_notify_one(struct snd_card *card, unsigned int mask, struct snd_kcontrol *kctl, unsigned int ioff) { struct snd_ctl_elem_id id = kctl->id; + struct snd_ctl_layer_ops *lops; id.index += ioff; id.numid += ioff; snd_ctl_notify(card, mask, &id); + down_read(&snd_ctl_layer_rwsem); + for (lops = snd_ctl_layer; lops; lops = lops->next) + lops->lnotify(card, mask, kctl, ioff); + up_read(&snd_ctl_layer_rwsem); } EXPORT_SYMBOL(snd_ctl_notify_one); @@ -1997,6 +2004,84 @@ EXPORT_SYMBOL_GPL(snd_ctl_get_preferred_subdevice); #define snd_ctl_ioctl_compat NULL #endif +/* + * control layers (audio LED etc.) + */ + +/** + * snd_ctl_request_layer - request to use the layer + * @module_name: Name of the kernel module (NULL == build-in) + * + * Return an error code when the module cannot be loaded. + */ +int snd_ctl_request_layer(const char *module_name) +{ + struct snd_ctl_layer_ops *lops; + + if (module_name == NULL) + return 0; + down_read(&snd_ctl_layer_rwsem); + for (lops = snd_ctl_layer; lops; lops = lops->next) + if (strcmp(lops->module_name, module_name) == 0) + break; + up_read(&snd_ctl_layer_rwsem); + if (lops) + return 0; + return request_module(module_name); +} +EXPORT_SYMBOL_GPL(snd_ctl_request_layer); + +/** + * snd_ctl_register_layer - register new control layer + * @lops: operation structure + * + * The new layer can track all control elements and do additional + * operations on top (like audio LED handling). + */ +void snd_ctl_register_layer(struct snd_ctl_layer_ops *lops) +{ + struct snd_card *card; + int card_number; + + down_write(&snd_ctl_layer_rwsem); + lops->next = snd_ctl_layer; + snd_ctl_layer = lops; + for (card_number = 0; card_number < SNDRV_CARDS; card_number++) { + card = snd_card_ref(card_number); + if (card) { + lops->lregister(card); + snd_card_unref(card); + } + } + up_write(&snd_ctl_layer_rwsem); +} +EXPORT_SYMBOL_GPL(snd_ctl_register_layer); + +/** + * snd_ctl_disconnect_layer - disconnect control layer + * @lops: operation structure + * + * It is expected that the information about tracked cards + * is freed before this call (the disconnect callback is + * not called here). + */ +void snd_ctl_disconnect_layer(struct snd_ctl_layer_ops *lops) +{ + struct snd_ctl_layer_ops *lops2, *prev_lops2; + + down_write(&snd_ctl_layer_rwsem); + for (lops2 = snd_ctl_layer, prev_lops2 = NULL; lops2; lops2 = lops2->next) + if (lops2 == lops) { + if (!prev_lops2) + snd_ctl_layer = lops->next; + else + prev_lops2->next = lops->next; + break; + } + up_write(&snd_ctl_layer_rwsem); +} +EXPORT_SYMBOL_GPL(snd_ctl_disconnect_layer); + /* * INIT PART */ @@ -2020,9 +2105,18 @@ static const struct file_operations snd_ctl_f_ops = static int snd_ctl_dev_register(struct snd_device *device) { struct snd_card *card = device->device_data; + struct snd_ctl_layer_ops *lops; + int err; - return snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1, - &snd_ctl_f_ops, card, &card->ctl_dev); + err = snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1, + &snd_ctl_f_ops, card, &card->ctl_dev); + if (err < 0) + return err; + down_read(&snd_ctl_layer_rwsem); + for (lops = snd_ctl_layer; lops; lops = lops->next) + lops->lregister(card); + up_read(&snd_ctl_layer_rwsem); + return 0; } /* @@ -2032,6 +2126,7 @@ static int snd_ctl_dev_disconnect(struct snd_device *device) { struct snd_card *card = device->device_data; struct snd_ctl_file *ctl; + struct snd_ctl_layer_ops *lops; unsigned long flags; read_lock_irqsave(&card->ctl_files_rwlock, flags); @@ -2041,6 +2136,11 @@ static int snd_ctl_dev_disconnect(struct snd_device *device) } read_unlock_irqrestore(&card->ctl_files_rwlock, flags); + down_read(&snd_ctl_layer_rwsem); + for (lops = snd_ctl_layer; lops; lops = lops->next) + lops->ldisconnect(card); + up_read(&snd_ctl_layer_rwsem); + return snd_unregister_device(&card->ctl_dev); }