From patchwork Wed Feb 24 22:46:06 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sakari Ailus X-Patchwork-Id: 2825 Return-path: Envelope-to: mchehab@infradead.org Delivery-date: Wed, 24 Feb 2010 22:46:23 +0000 Received: from bombadil.infradead.org [18.85.46.34] by pedra with IMAP (fetchmail-6.3.6) for (single-drop); Wed, 24 Feb 2010 19:49:47 -0300 (BRT) Received: from vger.kernel.org ([209.132.180.67]) by bombadil.infradead.org with esmtp (Exim 4.69 #1 (Red Hat Linux)) id 1NkPzq-0006ul-RW; Wed, 24 Feb 2010 22:46:23 +0000 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758516Ab0BXWqV (ORCPT + 1 other); Wed, 24 Feb 2010 17:46:21 -0500 Received: from smtp.nokia.com ([192.100.105.134]:39978 "EHLO mgw-mx09.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758082Ab0BXWqU (ORCPT ); Wed, 24 Feb 2010 17:46:20 -0500 Received: from vaebh106.NOE.Nokia.com (vaebh106.europe.nokia.com [10.160.244.32]) by mgw-mx09.nokia.com (Switch-3.3.3/Switch-3.3.3) with ESMTP id o1OMkAJT022142; Wed, 24 Feb 2010 16:46:17 -0600 Received: from vaebh104.NOE.Nokia.com ([10.160.244.30]) by vaebh106.NOE.Nokia.com with Microsoft SMTPSVC(6.0.3790.3959); Thu, 25 Feb 2010 00:46:15 +0200 Received: from mgw-da02.ext.nokia.com ([147.243.128.26]) by vaebh104.NOE.Nokia.com over TLS secured channel with Microsoft SMTPSVC(6.0.3790.3959); Thu, 25 Feb 2010 00:46:14 +0200 Received: from maxwell.research.nokia.com (maxwell.research.nokia.com [172.21.50.162]) by mgw-da02.ext.nokia.com (Switch-3.3.3/Switch-3.3.3) with ESMTP id o1OMk85e026153 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 25 Feb 2010 00:46:10 +0200 Received: from kaali.localdomain (kaali.localdomain [192.168.239.7]) by maxwell.research.nokia.com (Postfix) with ESMTPS id 4FC7A7010B; Thu, 25 Feb 2010 00:46:08 +0200 (EET) Received: from sailus by kaali.localdomain with local (Exim 4.69) (envelope-from ) id 1NkPzc-0001Xb-7B; Thu, 25 Feb 2010 00:46:08 +0200 From: Sakari Ailus To: linux-media@vger.kernel.org Cc: hverkuil@xs4all.nl, laurent.pinchart@ideasonboard.com, david.cohen@nokia.com Subject: [PATCH v8 4/6] V4L: Events: Add backend Date: Thu, 25 Feb 2010 00:46:06 +0200 Message-Id: <1267051568-5757-4-git-send-email-sakari.ailus@maxwell.research.nokia.com> X-Mailer: git-send-email 1.5.6.5 In-Reply-To: <4B85AC1E.8060302@maxwell.research.nokia.com> References: <4B85AC1E.8060302@maxwell.research.nokia.com> X-OriginalArrivalTime: 24 Feb 2010 22:46:15.0680 (UTC) FILETIME=[2C0C9800:01CAB5A3] X-Nokia-AV: Clean Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Add event handling backend to V4L2. The backend handles event subscription and delivery to file handles. Event subscriptions are based on file handle. Events may be delivered to all subscribed file handles on a device independent of where they originate from. Signed-off-by: Sakari Ailus --- drivers/media/video/Makefile | 3 +- drivers/media/video/v4l2-event.c | 289 ++++++++++++++++++++++++++++++++++++++ drivers/media/video/v4l2-fh.c | 6 +- include/media/v4l2-event.h | 67 +++++++++ include/media/v4l2-fh.h | 2 + 5 files changed, 365 insertions(+), 2 deletions(-) create mode 100644 drivers/media/video/v4l2-event.c create mode 100644 include/media/v4l2-event.h diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile index 14bf69a..b84abfe 100644 --- a/drivers/media/video/Makefile +++ b/drivers/media/video/Makefile @@ -10,7 +10,8 @@ stkwebcam-objs := stk-webcam.o stk-sensor.o omap2cam-objs := omap24xxcam.o omap24xxcam-dma.o -videodev-objs := v4l2-dev.o v4l2-ioctl.o v4l2-device.o v4l2-fh.o +videodev-objs := v4l2-dev.o v4l2-ioctl.o v4l2-device.o v4l2-fh.o \ + v4l2-event.o # V4L2 core modules diff --git a/drivers/media/video/v4l2-event.c b/drivers/media/video/v4l2-event.c new file mode 100644 index 0000000..aea4332 --- /dev/null +++ b/drivers/media/video/v4l2-event.c @@ -0,0 +1,289 @@ +/* + * v4l2-event.c + * + * V4L2 events. + * + * Copyright (C) 2009--2010 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 + +#include + +int v4l2_event_init(struct v4l2_fh *fh) +{ + 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); + + fh->events->sequence = -1; + + return 0; +} + +int v4l2_event_alloc(struct v4l2_fh *fh, unsigned int n) +{ + struct v4l2_events *events = fh->events; + unsigned long flags; + + if (!events) { + WARN_ON(1); + return -ENOMEM; + } + + while (events->nallocated < 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); + events->nallocated++; + spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); + } + + return 0; +} +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_free(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_free); + +static 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; + } + + WARN_ON(events->navailable == 0); + + kev = list_first_entry(&events->available, struct v4l2_kevent, list); + list_move(&kev->list, &events->free); + events->navailable--; + + kev->event.pending = events->navailable; + *event = kev->event; + + spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); + + return 0; +} + +int v4l2_event_dequeue(struct v4l2_fh *fh, struct v4l2_event *event, + int nonblocking) +{ + struct v4l2_events *events = fh->events; + int ret; + + if (nonblocking) + return __v4l2_event_dequeue(fh, event); + + do { + ret = wait_event_interruptible(events->wait, + events->navailable != 0); + if (ret < 0) + return ret; + + ret = __v4l2_event_dequeue(fh, event); + } while (ret == -ENOENT); + + return ret; +} + +/* Caller must hold fh->event->lock! */ +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; + + WARN_ON(!spin_is_locked(&fh->vdev->fh_lock)); + + list_for_each_entry(sev, &events->subscribed, list) { + if (sev->type == type) + return sev; + } + + return NULL; +} + +void v4l2_event_queue(struct video_device *vdev, const struct v4l2_event *ev) +{ + struct v4l2_fh *fh; + unsigned long flags; + struct timespec timestamp; + + ktime_get_ts(×tamp); + + 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; + + /* Are we subscribed? */ + if (!v4l2_event_subscribed(fh, ev->type)) + continue; + + /* Increase event sequence number on fh. */ + events->sequence++; + + /* Do we have any free events? */ + if (list_empty(&events->free)) + continue; + + /* Take one and fill it. */ + kev = list_first_entry(&events->free, struct v4l2_kevent, list); + kev->event.type = ev->type; + kev->event.u = ev->u; + kev->event.timestamp = timestamp; + kev->event.sequence = events->sequence; + list_move_tail(&kev->list, &events->available); + + events->navailable++; + + 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) +{ + return fh->events->navailable; +} +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; + + if (fh->events == NULL) { + WARN_ON(1); + return -ENOMEM; + } + + 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) { + INIT_LIST_HEAD(&sev->list); + sev->type = sub->type; + + list_add(&sev->list, &events->subscribed); + sev = NULL; + } + + spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); + + kfree(sev); + + return 0; +} +EXPORT_SYMBOL_GPL(v4l2_event_subscribe); + +static void v4l2_event_unsubscribe_all(struct v4l2_fh *fh) +{ + struct v4l2_events *events = fh->events; + struct v4l2_subscribed_event *sev; + unsigned long flags; + + do { + sev = NULL; + + spin_lock_irqsave(&fh->vdev->fh_lock, flags); + if (!list_empty(&events->subscribed)) { + sev = list_first_entry(&events->subscribed, + struct v4l2_subscribed_event, list); + list_del(&sev->list); + } + spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); + kfree(sev); + } while (sev); +} + +int v4l2_event_unsubscribe(struct v4l2_fh *fh, + struct v4l2_event_subscription *sub) +{ + struct v4l2_subscribed_event *sev; + unsigned long flags; + + if (sub->type == V4L2_EVENT_ALL) { + v4l2_event_unsubscribe_all(fh); + return 0; + } + + spin_lock_irqsave(&fh->vdev->fh_lock, flags); + + sev = v4l2_event_subscribed(fh, sub->type); + if (sev != NULL) + list_del(&sev->list); + + spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); + + kfree(sev); + + 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 93ea0af..aab2fb6 100644 --- a/drivers/media/video/v4l2-fh.c +++ b/drivers/media/video/v4l2-fh.c @@ -25,6 +25,8 @@ #include #include #include +#include +#include int v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev) { @@ -32,7 +34,7 @@ int v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev) INIT_LIST_HEAD(&fh->list); set_bit(V4L2_FL_USES_V4L2_FH, &fh->vdev->flags); - return 0; + return v4l2_event_init(fh); } EXPORT_SYMBOL_GPL(v4l2_fh_init); @@ -62,5 +64,7 @@ void v4l2_fh_exit(struct v4l2_fh *fh) return; fh->vdev = NULL; + + v4l2_event_free(fh); } 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..3b86177 --- /dev/null +++ b/include/media/v4l2-event.h @@ -0,0 +1,67 @@ +/* + * v4l2-event.h + * + * V4L2 events. + * + * Copyright (C) 2009--2010 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 +#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 free; /* Events ready for use */ + struct list_head available; /* Dequeueable event */ + unsigned int navailable; + unsigned int nallocated; /* Number of allocated events */ + u32 sequence; +}; + +int v4l2_event_init(struct v4l2_fh *fh); +int v4l2_event_alloc(struct v4l2_fh *fh, unsigned int n); +void v4l2_event_free(struct v4l2_fh *fh); +int v4l2_event_dequeue(struct v4l2_fh *fh, struct v4l2_event *event, + int nonblocking); +void v4l2_event_queue(struct video_device *vdev, const 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 410e86c..1d48c15 100644 --- a/include/media/v4l2-fh.h +++ b/include/media/v4l2-fh.h @@ -28,10 +28,12 @@ #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 */ }; int v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev);