From patchwork Tue Feb 9 18:26:47 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sakari Ailus X-Patchwork-Id: 78084 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter.kernel.org (8.14.3/8.14.3) with ESMTP id o19IR93m017156 for ; Tue, 9 Feb 2010 18:27:13 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751029Ab0BIS1L (ORCPT ); Tue, 9 Feb 2010 13:27:11 -0500 Received: from smtp.nokia.com ([192.100.122.230]:22918 "EHLO mgw-mx03.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750942Ab0BIS1G (ORCPT ); Tue, 9 Feb 2010 13:27:06 -0500 Received: from vaebh105.NOE.Nokia.com (vaebh105.europe.nokia.com [10.160.244.31]) by mgw-mx03.nokia.com (Switch-3.3.3/Switch-3.3.3) with ESMTP id o19IQhf3030359; Tue, 9 Feb 2010 20:27:02 +0200 Received: from esebh102.NOE.Nokia.com ([172.21.138.183]) by vaebh105.NOE.Nokia.com with Microsoft SMTPSVC(6.0.3790.3959); Tue, 9 Feb 2010 20:26:52 +0200 Received: from mgw-sa02.ext.nokia.com ([147.243.1.48]) by esebh102.NOE.Nokia.com over TLS secured channel with Microsoft SMTPSVC(6.0.3790.3959); Tue, 9 Feb 2010 20:26:52 +0200 Received: from maxwell.research.nokia.com (maxwell.research.nokia.com [172.21.50.162]) by mgw-sa02.ext.nokia.com (Switch-3.3.3/Switch-3.3.3) with ESMTP id o19IQo11003283 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Tue, 9 Feb 2010 20:26:51 +0200 Received: from lanttu (lanttu.localdomain [192.168.239.4]) by maxwell.research.nokia.com (Postfix) with ESMTPS id C0F217010C; Tue, 9 Feb 2010 20:26:50 +0200 (EET) Received: from sakke by lanttu with local (Exim 4.69) (envelope-from ) id 1NeunS-0006IE-Ge; Tue, 09 Feb 2010 20:26:50 +0200 From: Sakari Ailus To: linux-media@vger.kernel.org Cc: hverkuil@xs4all.nl, laurent.pinchart@ideasonboard.com, iivanov@mm-sol.com, gururaj.nagendra@intel.com, david.cohen@nokia.com Subject: [PATCH v3 4/7] V4L: Events: Add backend Date: Tue, 9 Feb 2010 20:26:47 +0200 Message-Id: <1265740010-24144-4-git-send-email-sakari.ailus@maxwell.research.nokia.com> X-Mailer: git-send-email 1.5.6.5 In-Reply-To: <1265740010-24144-3-git-send-email-sakari.ailus@maxwell.research.nokia.com> References: <4B71A8DF.8070907@maxwell.research.nokia.com> <1265740010-24144-1-git-send-email-sakari.ailus@maxwell.research.nokia.com> <1265740010-24144-2-git-send-email-sakari.ailus@maxwell.research.nokia.com> <1265740010-24144-3-git-send-email-sakari.ailus@maxwell.research.nokia.com> X-OriginalArrivalTime: 09 Feb 2010 18:26:52.0907 (UTC) FILETIME=[73B7A3B0:01CAA9B5] X-Nokia-AV: Clean Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter.kernel.org [140.211.167.41]); Tue, 09 Feb 2010 18:27:13 +0000 (UTC) diff --git a/drivers/media/video/v4l2-event.c b/drivers/media/video/v4l2-event.c new file mode 100644 index 0000000..9f5be94 --- /dev/null +++ b/drivers/media/video/v4l2-event.c @@ -0,0 +1,258 @@ +/* + * drivers/media/video/v4l2-event.c + * + * V4L2 events. + * + * Copyright (C) 2009 Nokia Corporation. + * + * Contact: Sakari Ailus + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA + */ + +#include +#include + +#include + +/* In error case, return number of events *not* allocated. */ +int v4l2_event_alloc(struct v4l2_fh *fh, unsigned int n) +{ + struct v4l2_events *events = fh->events; + unsigned long flags; + + for (; n > 0; n--) { + struct v4l2_kevent *kev; + + kev = kzalloc(sizeof(*kev), GFP_KERNEL); + if (kev == NULL) + return -ENOMEM; + + spin_lock_irqsave(&fh->vdev->fh_lock, flags); + list_add_tail(&kev->list, &events->free); + spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); + } + + return n; +} +EXPORT_SYMBOL_GPL(v4l2_event_alloc); + +#define list_kfree(list, type, member) \ + while (!list_empty(list)) { \ + type *hi; \ + hi = list_first_entry(list, type, member); \ + list_del(&hi->member); \ + kfree(hi); \ + } + +void v4l2_event_exit(struct v4l2_fh *fh) +{ + struct v4l2_events *events = fh->events; + + if (!events) + return; + + list_kfree(&events->free, struct v4l2_kevent, list); + list_kfree(&events->available, struct v4l2_kevent, list); + list_kfree(&events->subscribed, struct v4l2_subscribed_event, list); + + kfree(events); + fh->events = NULL; +} +EXPORT_SYMBOL_GPL(v4l2_event_exit); + +int v4l2_event_init(struct v4l2_fh *fh, unsigned int n) +{ + int ret; + + fh->events = kzalloc(sizeof(*fh->events), GFP_KERNEL); + if (fh->events == NULL) + return -ENOMEM; + + init_waitqueue_head(&fh->events->wait); + + INIT_LIST_HEAD(&fh->events->free); + INIT_LIST_HEAD(&fh->events->available); + INIT_LIST_HEAD(&fh->events->subscribed); + + ret = v4l2_event_alloc(fh, n); + if (ret < 0) + v4l2_event_exit(fh); + + return ret; +} +EXPORT_SYMBOL_GPL(v4l2_event_init); + +int v4l2_event_dequeue(struct v4l2_fh *fh, struct v4l2_event *event) +{ + struct v4l2_events *events = fh->events; + struct v4l2_kevent *kev; + unsigned long flags; + + spin_lock_irqsave(&fh->vdev->fh_lock, flags); + + if (list_empty(&events->available)) { + spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); + return -ENOENT; + } + + kev = list_first_entry(&events->available, struct v4l2_kevent, list); + list_move(&kev->list, &events->free); + + kev->event.count = !list_empty(&events->available); + + *event = kev->event; + + spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); + + return 0; +} +EXPORT_SYMBOL_GPL(v4l2_event_dequeue); + +static struct v4l2_subscribed_event *__v4l2_event_subscribed( + struct v4l2_fh *fh, u32 type) +{ + struct v4l2_events *events = fh->events; + struct v4l2_subscribed_event *sev; + + list_for_each_entry(sev, &events->subscribed, list) { + if (sev->type == type) + return sev; + } + + return NULL; +} + +struct v4l2_subscribed_event *v4l2_event_subscribed( + struct v4l2_fh *fh, u32 type) +{ + struct v4l2_subscribed_event *sev; + unsigned long flags; + + spin_lock_irqsave(&fh->vdev->fh_lock, flags); + + sev = __v4l2_event_subscribed(fh, type); + + spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); + + return sev; +} +EXPORT_SYMBOL_GPL(v4l2_event_subscribed); + +void v4l2_event_queue(struct video_device *vdev, struct v4l2_event *ev) +{ + struct v4l2_fh *fh; + unsigned long flags; + + spin_lock_irqsave(&vdev->fh_lock, flags); + + list_for_each_entry(fh, &vdev->fh_list, list) { + struct v4l2_events *events = fh->events; + struct v4l2_kevent *kev; + + /* Do we have any free events and are we subscribed? */ + if (list_empty(&events->free) || + !__v4l2_event_subscribed(fh, ev->type)) + continue; + + /* Take one and fill it. */ + kev = list_first_entry(&events->free, struct v4l2_kevent, list); + kev->event = *ev; + list_move_tail(&kev->list, &events->available); + + wake_up_all(&events->wait); + } + + spin_unlock_irqrestore(&vdev->fh_lock, flags); +} +EXPORT_SYMBOL_GPL(v4l2_event_queue); + +int v4l2_event_pending(struct v4l2_fh *fh) +{ + struct v4l2_events *events = fh->events; + unsigned long flags; + int ret; + + spin_lock_irqsave(&fh->vdev->fh_lock, flags); + ret = !list_empty(&events->available); + spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); + + return ret; +} +EXPORT_SYMBOL_GPL(v4l2_event_pending); + +int v4l2_event_subscribe(struct v4l2_fh *fh, + struct v4l2_event_subscription *sub) +{ + struct v4l2_events *events = fh->events; + struct v4l2_subscribed_event *sev; + unsigned long flags; + int ret = 0; + + /* Allow subscribing to valid events only. */ + if (sub->type < V4L2_EVENT_PRIVATE_START) + switch (sub->type) { + default: + return -EINVAL; + } + + sev = kmalloc(sizeof(*sev), GFP_KERNEL); + if (!sev) + return -ENOMEM; + + spin_lock_irqsave(&fh->vdev->fh_lock, flags); + + if (__v4l2_event_subscribed(fh, sub->type) != NULL) { + ret = -EBUSY; + goto out; + } + + INIT_LIST_HEAD(&sev->list); + sev->type = sub->type; + + list_add(&sev->list, &events->subscribed); + +out: + spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); + + if (ret) + kfree(sev); + + return ret; +} +EXPORT_SYMBOL_GPL(v4l2_event_subscribe); + +int v4l2_event_unsubscribe(struct v4l2_fh *fh, + struct v4l2_event_subscription *sub) +{ + struct v4l2_subscribed_event *sev; + unsigned long flags; + + spin_lock_irqsave(&fh->vdev->fh_lock, flags); + + sev = __v4l2_event_subscribed(fh, sub->type); + + if (sev == NULL) { + spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); + return -EINVAL; + } + + list_del(&sev->list); + + spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); + + return 0; +} +EXPORT_SYMBOL_GPL(v4l2_event_unsubscribe); diff --git a/drivers/media/video/v4l2-fh.c b/drivers/media/video/v4l2-fh.c index d2b8cef..dac82ff 100644 --- a/drivers/media/video/v4l2-fh.c +++ b/drivers/media/video/v4l2-fh.c @@ -24,6 +24,7 @@ #include #include +#include void v4l2_fh_init(struct video_device *vdev, struct v4l2_fh *fh) { @@ -54,6 +55,9 @@ EXPORT_SYMBOL_GPL(v4l2_fh_del); void v4l2_fh_exit(struct v4l2_fh *fh) { BUG_ON(fh->vdev == NULL); + + v4l2_event_exit(fh); + fh->vdev = NULL; } EXPORT_SYMBOL_GPL(v4l2_fh_exit); diff --git a/include/media/v4l2-event.h b/include/media/v4l2-event.h new file mode 100644 index 0000000..580c9d4 --- /dev/null +++ b/include/media/v4l2-event.h @@ -0,0 +1,64 @@ +/* + * include/media/v4l2-event.h + * + * V4L2 events. + * + * Copyright (C) 2009 Nokia Corporation. + * + * Contact: Sakari Ailus + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA + */ + +#ifndef V4L2_EVENT_H +#define V4L2_EVENT_H + +#include +#include + +struct v4l2_fh; +struct video_device; + +struct v4l2_kevent { + struct list_head list; + struct v4l2_event event; +}; + +struct v4l2_subscribed_event { + struct list_head list; + u32 type; +}; + +struct v4l2_events { + wait_queue_head_t wait; + struct list_head subscribed; /* Subscribed events */ + struct list_head available; /* Dequeueable event */ + struct list_head free; /* Events ready for use */ +}; + +int v4l2_event_alloc(struct v4l2_fh *fh, unsigned int n); +int v4l2_event_init(struct v4l2_fh *fh, unsigned int n); +void v4l2_event_exit(struct v4l2_fh *fh); +int v4l2_event_dequeue(struct v4l2_fh *fh, struct v4l2_event *event); +struct v4l2_subscribed_event *v4l2_event_subscribed( + struct v4l2_fh *fh, u32 type); +void v4l2_event_queue(struct video_device *vdev, struct v4l2_event *ev); +int v4l2_event_pending(struct v4l2_fh *fh); +int v4l2_event_subscribe(struct v4l2_fh *fh, + struct v4l2_event_subscription *sub); +int v4l2_event_unsubscribe(struct v4l2_fh *fh, + struct v4l2_event_subscription *sub); + +#endif /* V4L2_EVENT_H */ diff --git a/include/media/v4l2-fh.h b/include/media/v4l2-fh.h index 0960742..2a32ad0 100644 --- a/include/media/v4l2-fh.h +++ b/include/media/v4l2-fh.h @@ -31,10 +31,12 @@ #include struct video_device; +struct v4l2_events; struct v4l2_fh { struct list_head list; struct video_device *vdev; + struct v4l2_events *events; /* events, pending and subscribed */ }; void v4l2_fh_init(struct video_device *vdev, struct v4l2_fh *fh);