From 02adb1cc765b8c29dc83c6602bda19003cce62f1 Mon Sep 17 00:00:00 2001 From: Sakari Ailus Date: Wed, 3 Mar 2010 12:49:38 -0300 Subject: [PATCH] [media] v4l: subdev: Events support Provide v4l2_subdevs with v4l2_event support. Subdev drivers only need very little to support events. Signed-off-by: Sakari Ailus Signed-off-by: David Cohen Signed-off-by: Laurent Pinchart Acked-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/v4l2-framework.txt | 18 +++++ drivers/media/video/v4l2-subdev.c | 78 +++++++++++++++++++- include/media/v4l2-subdev.h | 10 +++ 3 files changed, 105 insertions(+), 1 deletion(-) diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index 1feecfc59c3d..eb8479565dc4 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -350,6 +350,24 @@ VIDIOC_TRY_EXT_CTRLS controls can be also be accessed through one (or several) V4L2 device nodes. +VIDIOC_DQEVENT +VIDIOC_SUBSCRIBE_EVENT +VIDIOC_UNSUBSCRIBE_EVENT + + The events ioctls are identical to the ones defined in V4L2. They + behave identically, with the only exception that they deal only with + events generated by the sub-device. Depending on the driver, those + events can also be reported by one (or several) V4L2 device nodes. + + Sub-device drivers that want to use events need to set the + V4L2_SUBDEV_USES_EVENTS v4l2_subdev::flags and initialize + v4l2_subdev::nevents to events queue depth before registering the + sub-device. After registration events can be queued as usual on the + v4l2_subdev::devnode device node. + + To properly support events, the poll() file operation is also + implemented. + I2C sub-device drivers ---------------------- diff --git a/drivers/media/video/v4l2-subdev.c b/drivers/media/video/v4l2-subdev.c index da10430051c0..0c67f5a278fb 100644 --- a/drivers/media/video/v4l2-subdev.c +++ b/drivers/media/video/v4l2-subdev.c @@ -20,21 +20,66 @@ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ -#include #include +#include +#include #include #include #include #include +#include +#include static int subdev_open(struct file *file) { + struct video_device *vdev = video_devdata(file); + struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev); + struct v4l2_fh *vfh; + int ret; + + if (sd->flags & V4L2_SUBDEV_FL_HAS_EVENTS) { + vfh = kzalloc(sizeof(*vfh), GFP_KERNEL); + if (vfh == NULL) + return -ENOMEM; + + ret = v4l2_fh_init(vfh, vdev); + if (ret) + goto err; + + ret = v4l2_event_init(vfh); + if (ret) + goto err; + + ret = v4l2_event_alloc(vfh, sd->nevents); + if (ret) + goto err; + + v4l2_fh_add(vfh); + file->private_data = vfh; + } + return 0; + +err: + if (vfh != NULL) { + v4l2_fh_exit(vfh); + kfree(vfh); + } + + return ret; } static int subdev_close(struct file *file) { + struct v4l2_fh *vfh = file->private_data; + + if (vfh != NULL) { + v4l2_fh_del(vfh); + v4l2_fh_exit(vfh); + kfree(vfh); + } + return 0; } @@ -42,6 +87,7 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg) { struct video_device *vdev = video_devdata(file); struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev); + struct v4l2_fh *fh = file->private_data; switch (cmd) { case VIDIOC_QUERYCTRL: @@ -65,6 +111,18 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg) case VIDIOC_TRY_EXT_CTRLS: return v4l2_subdev_try_ext_ctrls(sd, arg); + case VIDIOC_DQEVENT: + if (!(sd->flags & V4L2_SUBDEV_FL_HAS_EVENTS)) + return -ENOIOCTLCMD; + + return v4l2_event_dequeue(fh, arg, file->f_flags & O_NONBLOCK); + + case VIDIOC_SUBSCRIBE_EVENT: + return v4l2_subdev_call(sd, core, subscribe_event, fh, arg); + + case VIDIOC_UNSUBSCRIBE_EVENT: + return v4l2_subdev_call(sd, core, unsubscribe_event, fh, arg); + default: return -ENOIOCTLCMD; } @@ -78,11 +136,29 @@ static long subdev_ioctl(struct file *file, unsigned int cmd, return video_usercopy(file, cmd, arg, subdev_do_ioctl); } +static unsigned int subdev_poll(struct file *file, poll_table *wait) +{ + struct video_device *vdev = video_devdata(file); + struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev); + struct v4l2_fh *fh = file->private_data; + + if (!(sd->flags & V4L2_SUBDEV_FL_HAS_EVENTS)) + return POLLERR; + + poll_wait(file, &fh->events->wait, wait); + + if (v4l2_event_pending(fh)) + return POLLPRI; + + return 0; +} + const struct v4l2_file_operations v4l2_subdev_fops = { .owner = THIS_MODULE, .open = subdev_open, .unlocked_ioctl = subdev_ioctl, .release = subdev_close, + .poll = subdev_poll, }; void v4l2_subdev_init(struct v4l2_subdev *sd, const struct v4l2_subdev_ops *ops) diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h index 3276065022ef..0f9937be53d2 100644 --- a/include/media/v4l2-subdev.h +++ b/include/media/v4l2-subdev.h @@ -37,6 +37,8 @@ struct v4l2_device; struct v4l2_ctrl_handler; +struct v4l2_event_subscription; +struct v4l2_fh; struct v4l2_subdev; struct tuner_setup; @@ -161,6 +163,10 @@ struct v4l2_subdev_core_ops { int (*s_power)(struct v4l2_subdev *sd, int on); int (*interrupt_service_routine)(struct v4l2_subdev *sd, u32 status, bool *handled); + int (*subscribe_event)(struct v4l2_subdev *sd, struct v4l2_fh *fh, + struct v4l2_event_subscription *sub); + int (*unsubscribe_event)(struct v4l2_subdev *sd, struct v4l2_fh *fh, + struct v4l2_event_subscription *sub); }; /* s_mode: switch the tuner to a specific tuner mode. Replacement of s_radio. @@ -437,6 +443,8 @@ struct v4l2_subdev_internal_ops { #define V4L2_SUBDEV_FL_IS_SPI (1U << 1) /* Set this flag if this subdev needs a device node. */ #define V4L2_SUBDEV_FL_HAS_DEVNODE (1U << 2) +/* Set this flag if this subdev generates events. */ +#define V4L2_SUBDEV_FL_HAS_EVENTS (1U << 3) /* Each instance of a subdev driver should create this struct, either stand-alone or embedded in a larger struct. @@ -460,6 +468,8 @@ struct v4l2_subdev { void *host_priv; /* subdev device node */ struct video_device devnode; + /* number of events to be allocated on open */ + unsigned int nevents; }; #define vdev_to_v4l2_subdev(vdev) \