From patchwork Tue Dec 22 16:43:08 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sakari Ailus X-Patchwork-Id: 69298 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter.kernel.org (8.14.3/8.14.2) with ESMTP id nBMGiJsK002018 for ; Tue, 22 Dec 2009 16:44:20 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754126AbZLVQoG (ORCPT ); Tue, 22 Dec 2009 11:44:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753726AbZLVQoB (ORCPT ); Tue, 22 Dec 2009 11:44:01 -0500 Received: from smtp.nokia.com ([192.100.105.134]:39906 "EHLO mgw-mx09.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754106AbZLVQnn (ORCPT ); Tue, 22 Dec 2009 11:43:43 -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 nBMGhT8W009151; Tue, 22 Dec 2009 10:43:39 -0600 Received: from esebh102.NOE.Nokia.com ([172.21.138.183]) by vaebh106.NOE.Nokia.com with Microsoft SMTPSVC(6.0.3790.3959); Tue, 22 Dec 2009 18:43:16 +0200 Received: from mgw-da02.ext.nokia.com ([147.243.128.26]) by esebh102.NOE.Nokia.com over TLS secured channel with Microsoft SMTPSVC(6.0.3790.3959); Tue, 22 Dec 2009 18:43:16 +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 nBMGhCb9024385; Tue, 22 Dec 2009 18:43:13 +0200 Received: from lanttu (lanttu.localdomain [192.168.239.4]) by maxwell.research.nokia.com (Postfix) with ESMTPS id 65BB57010B; Tue, 22 Dec 2009 18:43:12 +0200 (EET) Received: from sakke by lanttu with local (Exim 4.69) (envelope-from ) id 1NN7pI-0002Su-1D; Tue, 22 Dec 2009 18:43:12 +0200 From: Sakari Ailus To: linux-media@vger.kernel.org Cc: laurent.pinchart@ideasonboard.com, iivanov@mm-sol.com, hverkuil@xs4all.nl, gururaj.nagendra@intel.com Subject: [RFC v2 4/7] V4L: Events: Add backend Date: Tue, 22 Dec 2009 18:43:08 +0200 Message-Id: <1261500191-9441-4-git-send-email-sakari.ailus@maxwell.research.nokia.com> X-Mailer: git-send-email 1.5.6.5 In-Reply-To: <1261500191-9441-3-git-send-email-sakari.ailus@maxwell.research.nokia.com> References: <4B30F713.8070004@maxwell.research.nokia.com> <1261500191-9441-1-git-send-email-sakari.ailus@maxwell.research.nokia.com> <1261500191-9441-2-git-send-email-sakari.ailus@maxwell.research.nokia.com> <1261500191-9441-3-git-send-email-sakari.ailus@maxwell.research.nokia.com> X-OriginalArrivalTime: 22 Dec 2009 16:43:16.0924 (UTC) FILETIME=[DC7627C0:01CA8325] X-Nokia-AV: Clean Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile index 1947146..dd6a853 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-dev.c b/drivers/media/video/v4l2-dev.c index 15b2ac8..6d25297 100644 --- a/drivers/media/video/v4l2-dev.c +++ b/drivers/media/video/v4l2-dev.c @@ -613,22 +613,36 @@ static int __init videodev_init(void) dev_t dev = MKDEV(VIDEO_MAJOR, 0); int ret; + ret = v4l2_event_init(); + if (ret < 0) { + printk(KERN_WARNING "videodev: unable to initialise events\n"); + return ret; + } + printk(KERN_INFO "Linux video capture interface: v2.00\n"); ret = register_chrdev_region(dev, VIDEO_NUM_DEVICES, VIDEO_NAME); if (ret < 0) { printk(KERN_WARNING "videodev: unable to get major %d\n", VIDEO_MAJOR); - return ret; + goto out_register_chrdev_region; } ret = class_register(&video_class); if (ret < 0) { - unregister_chrdev_region(dev, VIDEO_NUM_DEVICES); printk(KERN_WARNING "video_dev: class_register failed\n"); - return -EIO; + ret = -EIO; + goto out_class_register; } return 0; + +out_class_register: + unregister_chrdev_region(dev, VIDEO_NUM_DEVICES); + +out_register_chrdev_region: + v4l2_event_exit(); + + return ret; } static void __exit videodev_exit(void) @@ -637,6 +651,7 @@ static void __exit videodev_exit(void) class_unregister(&video_class); unregister_chrdev_region(dev, VIDEO_NUM_DEVICES); + v4l2_event_exit(); } module_init(videodev_init) diff --git a/drivers/media/video/v4l2-event.c b/drivers/media/video/v4l2-event.c new file mode 100644 index 0000000..9fc0c81 --- /dev/null +++ b/drivers/media/video/v4l2-event.c @@ -0,0 +1,254 @@ +/* + * 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 + +static struct kmem_cache *event_kmem; + +int v4l2_event_init(void) +{ + event_kmem = kmem_cache_create("event_kmem", + sizeof(struct _v4l2_event), 0, + SLAB_HWCACHE_ALIGN, + NULL); + + if (!event_kmem) + return -ENOMEM; + + return 0; +} + +void v4l2_event_exit(void) +{ + kmem_cache_destroy(event_kmem); +} + +void v4l2_event_init_fh(struct v4l2_fh *fh) +{ + struct v4l2_events *events = &fh->events; + + init_waitqueue_head(&events->wait); + spin_lock_init(&events->lock); + + INIT_LIST_HEAD(&events->available); + INIT_LIST_HEAD(&events->subscribed); +} +EXPORT_SYMBOL_GPL(v4l2_event_init_fh); + +void v4l2_event_exit_fh(struct v4l2_fh *fh) +{ + struct v4l2_events *events = &fh->events; + + while (!list_empty(&events->available)) { + struct _v4l2_event *ev; + + ev = list_entry(events->available.next, + struct _v4l2_event, list); + + list_del(&ev->list); + + kmem_cache_free(event_kmem, ev); + } + + while (!list_empty(&events->subscribed)) { + struct v4l2_subscribed_event *sub; + + sub = list_entry(events->subscribed.next, + struct v4l2_subscribed_event, list); + + list_del(&sub->list); + + kfree(sub); + } +} +EXPORT_SYMBOL_GPL(v4l2_event_exit_fh); + +int v4l2_event_dequeue(struct v4l2_fh *fh, struct v4l2_event *event) +{ + struct v4l2_events *events = &fh->events; + struct _v4l2_event *ev; + unsigned long flags; + + spin_lock_irqsave(&events->lock, flags); + + if (list_empty(&events->available)) { + spin_unlock_irqrestore(&events->lock, flags); + return -ENOENT; + } + + ev = list_first_entry(&events->available, struct _v4l2_event, list); + list_del(&ev->list); + + ev->event.count = !list_empty(&events->available); + + spin_unlock_irqrestore(&events->lock, flags); + + memcpy(event, &ev->event, sizeof(ev->event)); + + kmem_cache_free(event_kmem, ev); + + 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 *ev; + + list_for_each_entry(ev, &events->subscribed, list) { + if (ev->type == type) + return ev; + } + + return NULL; +} + +struct v4l2_subscribed_event *v4l2_event_subscribed( + struct v4l2_fh *fh, u32 type) +{ + struct v4l2_events *events = &fh->events; + struct v4l2_subscribed_event *ev; + unsigned long flags; + + spin_lock_irqsave(&events->lock, flags); + + ev = __v4l2_event_subscribed(fh, type); + + spin_unlock_irqrestore(&events->lock, flags); + + return ev; +} +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) { + struct _v4l2_event *_ev; + + if (!v4l2_event_subscribed(fh, ev->type)) + continue; + + _ev = kmem_cache_alloc(event_kmem, GFP_ATOMIC); + if (!_ev) + continue; + + _ev->event = *ev; + + spin_lock(&fh->events.lock); + list_add_tail(&_ev->list, &fh->events.available); + spin_unlock(&fh->events.lock); + + wake_up_all(&fh->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(&events->lock, flags); + ret = !list_empty(&events->available); + spin_unlock_irqrestore(&events->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 *ev; + unsigned long flags; + int ret = 0; + + /* Allow subscribing to valid events only. */ + if (sub->type < V4L2_EVENT_PRIVATE_START) + switch (sub->type) { + case V4L2_EVENT_ALL: + break; + default: + return -EINVAL; + } + + ev = kmalloc(sizeof(*ev), GFP_KERNEL); + if (!ev) + return -ENOMEM; + + spin_lock_irqsave(&events->lock, flags); + + if (__v4l2_event_subscribed(fh, sub->type) != NULL) { + ret = -EBUSY; + goto out; + } + + INIT_LIST_HEAD(&ev->list); + ev->type = sub->type; + + list_add(&ev->list, &events->subscribed); + +out: + spin_unlock_irqrestore(&events->lock, flags); + + if (ret) + kfree(ev); + + return ret; +} +EXPORT_SYMBOL_GPL(v4l2_event_subscribe); + +int v4l2_event_unsubscribe(struct v4l2_fh *fh, + struct v4l2_event_subscription *sub) +{ + struct v4l2_events *events = &fh->events; + struct v4l2_subscribed_event *ev; + unsigned long flags; + + spin_lock_irqsave(&events->lock, flags); + + ev = __v4l2_event_subscribed(fh, sub->type); + + if (ev != NULL) + list_del(&ev->list); + + spin_unlock_irqrestore(&events->lock, flags); + + return ev == NULL; +} +EXPORT_SYMBOL_GPL(v4l2_event_unsubscribe); diff --git a/drivers/media/video/v4l2-fh.c b/drivers/media/video/v4l2-fh.c index 406e4ac..2b25ec9 100644 --- a/drivers/media/video/v4l2-fh.c +++ b/drivers/media/video/v4l2-fh.c @@ -32,6 +32,8 @@ int v4l2_fh_add(struct video_device *vdev, struct v4l2_fh *fh) { unsigned long flags; + v4l2_event_init_fh(fh); + spin_lock_irqsave(&vdev->fh_lock, flags); list_add(&fh->list, &vdev->fh); spin_unlock_irqrestore(&vdev->fh_lock, flags); @@ -44,6 +46,8 @@ void v4l2_fh_del(struct video_device *vdev, struct v4l2_fh *fh) { unsigned long flags; + v4l2_event_exit_fh(fh); + spin_lock_irqsave(&vdev->fh_lock, flags); list_del(&fh->list); spin_unlock_irqrestore(&vdev->fh_lock, flags); diff --git a/include/media/v4l2-event.h b/include/media/v4l2-event.h new file mode 100644 index 0000000..b11de92 --- /dev/null +++ b/include/media/v4l2-event.h @@ -0,0 +1,65 @@ +/* + * 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_event { + struct list_head list; + struct v4l2_event event; +}; + +struct v4l2_events { + spinlock_t lock; /* Protect everything here. */ + struct list_head available; + wait_queue_head_t wait; + struct list_head subscribed; /* Subscribed events. */ +}; + +struct v4l2_subscribed_event { + struct list_head list; + u32 type; +}; + +int v4l2_event_init(void); +void v4l2_event_exit(void); +void v4l2_event_init_fh(struct v4l2_fh *fh); +void v4l2_event_exit_fh(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 1efa916..c15bd13 100644 --- a/include/media/v4l2-fh.h +++ b/include/media/v4l2-fh.h @@ -28,8 +28,11 @@ #include #include +#include + struct v4l2_fh { struct list_head list; + struct v4l2_events events; /* events, pending and subscribed */ }; struct video_device;