Whenever a control changes value an event is sent to anyone that subscribed
to it.
Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
---
drivers/media/video/v4l2-ctrls.c | 59 ++++++++++++++++++
drivers/media/video/v4l2-event.c | 126 +++++++++++++++++++++++++++-----------
drivers/media/video/v4l2-fh.c | 4 +-
include/linux/videodev2.h | 17 +++++-
include/media/v4l2-ctrls.h | 9 +++
include/media/v4l2-event.h | 2 +
6 files changed, 177 insertions(+), 40 deletions(-)
diff --git a/drivers/media/video/v4l2-ctrls.c b/drivers/media/video/v4l2-ctrls.c
index f75a1d4..163f412 100644
--- a/drivers/media/video/v4l2-ctrls.c
+++ b/drivers/media/video/v4l2-ctrls.c
@@ -23,6 +23,7 @@
#include <media/v4l2-ioctl.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ctrls.h>
+#include <media/v4l2-event.h>
#include <media/v4l2-dev.h>
/* Internal temporary helper struct, one for each v4l2_ext_control */
@@ -537,6 +538,16 @@ static bool type_is_int(const struct v4l2_ctrl *ctrl)
}
}
+static void send_event(struct v4l2_ctrl *ctrl, struct v4l2_event *ev)
+{
+ struct v4l2_ctrl_fh *pos;
+
+ ev->id = ctrl->id;
+ list_for_each_entry(pos, &ctrl->fhs, node) {
+ v4l2_event_queue_fh(pos->fh, ev);
+ }
+}
+
/* Helper function: copy the current control value back to the caller */
static int cur_to_user(struct v4l2_ext_control *c,
struct v4l2_ctrl *ctrl)
@@ -626,20 +637,38 @@ static int new_to_user(struct v4l2_ext_control *c,
/* Copy the new value to the current value. */
static void new_to_cur(struct v4l2_ctrl *ctrl)
{
+ struct v4l2_event ev;
+ bool changed = false;
+
if (ctrl == NULL)
return;
switch (ctrl->type) {
+ case V4L2_CTRL_TYPE_BUTTON:
+ changed = true;
+ ev.u.ctrl_ch_value.value = 0;
+ break;
case V4L2_CTRL_TYPE_STRING:
/* strings are always 0-terminated */
+ changed = strcmp(ctrl->string, ctrl->cur.string);
strcpy(ctrl->cur.string, ctrl->string);
+ ev.u.ctrl_ch_value.value64 = 0;
break;
case V4L2_CTRL_TYPE_INTEGER64:
+ changed = ctrl->val64 != ctrl->cur.val64;
ctrl->cur.val64 = ctrl->val64;
+ ev.u.ctrl_ch_value.value64 = ctrl->val64;
break;
default:
+ changed = ctrl->val != ctrl->cur.val;
ctrl->cur.val = ctrl->val;
+ ev.u.ctrl_ch_value.value = ctrl->val;
break;
}
+ if (changed) {
+ ev.type = V4L2_EVENT_CTRL_CH_VALUE;
+ ev.u.ctrl_ch_value.type = ctrl->type;
+ send_event(ctrl, &ev);
+ }
}
/* Copy the current value to the new value */
@@ -784,6 +813,7 @@ void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl)
{
struct v4l2_ctrl_ref *ref, *next_ref;
struct v4l2_ctrl *ctrl, *next_ctrl;
+ struct v4l2_ctrl_fh *ctrl_fh, *next_ctrl_fh;
if (hdl == NULL || hdl->buckets == NULL)
return;
@@ -797,6 +827,10 @@ void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl)
/* Free all controls owned by the handler */
list_for_each_entry_safe(ctrl, next_ctrl, &hdl->ctrls, node) {
list_del(&ctrl->node);
+ list_for_each_entry_safe(ctrl_fh, next_ctrl_fh, &ctrl->fhs, node) {
+ list_del(&ctrl_fh->node);
+ kfree(ctrl_fh);
+ }
kfree(ctrl);
}
kfree(hdl->buckets);
@@ -1003,6 +1037,7 @@ static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl,
}
INIT_LIST_HEAD(&ctrl->node);
+ INIT_LIST_HEAD(&ctrl->fhs);
ctrl->handler = hdl;
ctrl->ops = ops;
ctrl->id = id;
@@ -1888,3 +1923,27 @@ int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val)
return set_ctrl(ctrl, &val);
}
EXPORT_SYMBOL(v4l2_ctrl_s_ctrl);
+
+void v4l2_ctrl_add_fh(struct v4l2_ctrl *ctrl, struct v4l2_ctrl_fh *ctrl_fh)
+{
+ v4l2_ctrl_lock(ctrl);
+ list_add_tail(&ctrl_fh->node, &ctrl->fhs);
+ v4l2_ctrl_unlock(ctrl);
+}
+EXPORT_SYMBOL(v4l2_ctrl_add_fh);
+
+void v4l2_ctrl_del_fh(struct v4l2_ctrl *ctrl, struct v4l2_fh *fh)
+{
+ struct v4l2_ctrl_fh *pos;
+
+ v4l2_ctrl_lock(ctrl);
+ list_for_each_entry(pos, &ctrl->fhs, node) {
+ if (pos->fh == fh) {
+ list_del(&pos->node);
+ kfree(pos);
+ break;
+ }
+ }
+ v4l2_ctrl_unlock(ctrl);
+}
+EXPORT_SYMBOL(v4l2_ctrl_del_fh);
diff --git a/drivers/media/video/v4l2-event.c b/drivers/media/video/v4l2-event.c
index 69fd343..c9251a5 100644
--- a/drivers/media/video/v4l2-event.c
+++ b/drivers/media/video/v4l2-event.c
@@ -25,10 +25,13 @@
#include <media/v4l2-dev.h>
#include <media/v4l2-fh.h>
#include <media/v4l2-event.h>
+#include <media/v4l2-ctrls.h>
#include <linux/sched.h>
#include <linux/slab.h>
+static void v4l2_event_unsubscribe_all(struct v4l2_fh *fh);
+
int v4l2_event_init(struct v4l2_fh *fh)
{
fh->events = kzalloc(sizeof(*fh->events), GFP_KERNEL);
@@ -91,7 +94,7 @@ void v4l2_event_free(struct v4l2_fh *fh)
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);
+ v4l2_event_unsubscribe_all(fh);
kfree(events);
fh->events = NULL;
@@ -154,9 +157,9 @@ int v4l2_event_dequeue(struct v4l2_fh *fh, struct v4l2_event *event,
}
EXPORT_SYMBOL_GPL(v4l2_event_dequeue);
-/* Caller must hold fh->event->lock! */
+/* Caller must hold fh->vdev->fh_lock! */
static struct v4l2_subscribed_event *v4l2_event_subscribed(
- struct v4l2_fh *fh, u32 type)
+ struct v4l2_fh *fh, u32 type, u32 id)
{
struct v4l2_events *events = fh->events;
struct v4l2_subscribed_event *sev;
@@ -164,13 +167,46 @@ static struct v4l2_subscribed_event *v4l2_event_subscribed(
assert_spin_locked(&fh->vdev->fh_lock);
list_for_each_entry(sev, &events->subscribed, list) {
- if (sev->type == type)
+ if (sev->type == type && sev->id == id)
return sev;
}
return NULL;
}
+static void __v4l2_event_queue_fh(struct v4l2_fh *fh, const struct v4l2_event *ev,
+ const struct timespec *ts)
+{
+ struct v4l2_events *events = fh->events;
+ struct v4l2_subscribed_event *sev;
+ struct v4l2_kevent *kev;
+
+ /* Are we subscribed? */
+ sev = v4l2_event_subscribed(fh, ev->type, ev->id);
+ if (sev == NULL)
+ return;
+
+ /* Increase event sequence number on fh. */
+ events->sequence++;
+
+ /* Do we have any free events? */
+ if (list_empty(&events->free))
+ return;
+
+ /* 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.id = ev->id;
+ kev->event.timestamp = *ts;
+ kev->event.sequence = events->sequence;
+ list_move_tail(&kev->list, &events->available);
+
+ events->navailable++;
+
+ wake_up_all(&events->wait);
+}
+
void v4l2_event_queue(struct video_device *vdev, const struct v4l2_event *ev)
{
struct v4l2_fh *fh;
@@ -182,37 +218,26 @@ void v4l2_event_queue(struct video_device *vdev, const struct v4l2_event *ev)
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);
+ __v4l2_event_queue_fh(fh, ev, ×tamp);
}
spin_unlock_irqrestore(&vdev->fh_lock, flags);
}
EXPORT_SYMBOL_GPL(v4l2_event_queue);
+void v4l2_event_queue_fh(struct v4l2_fh *fh, const struct v4l2_event *ev)
+{
+ unsigned long flags;
+ struct timespec timestamp;
+
+ ktime_get_ts(×tamp);
+
+ spin_lock_irqsave(&fh->vdev->fh_lock, flags);
+ __v4l2_event_queue_fh(fh, ev, ×tamp);
+ spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
+}
+EXPORT_SYMBOL_GPL(v4l2_event_queue_fh);
+
int v4l2_event_pending(struct v4l2_fh *fh)
{
return fh->events->navailable;
@@ -223,7 +248,9 @@ int v4l2_event_subscribe(struct v4l2_fh *fh,
struct v4l2_event_subscription *sub)
{
struct v4l2_events *events = fh->events;
- struct v4l2_subscribed_event *sev;
+ struct v4l2_subscribed_event *sev, *found_ev;
+ struct v4l2_ctrl *ctrl = NULL;
+ struct v4l2_ctrl_fh *ctrl_fh = NULL;
unsigned long flags;
if (fh->events == NULL) {
@@ -231,15 +258,31 @@ int v4l2_event_subscribe(struct v4l2_fh *fh,
return -ENOMEM;
}
+ if (sub->type == V4L2_EVENT_CTRL_CH_VALUE) {
+ ctrl = v4l2_ctrl_find(fh->ctrl_handler, sub->id);
+ if (ctrl == NULL)
+ return -EINVAL;
+ }
+
sev = kmalloc(sizeof(*sev), GFP_KERNEL);
if (!sev)
return -ENOMEM;
+ if (ctrl) {
+ ctrl_fh = kzalloc(sizeof(*ctrl_fh), GFP_KERNEL);
+ if (!ctrl_fh) {
+ kfree(sev);
+ return -ENOMEM;
+ }
+ ctrl_fh->fh = fh;
+ }
spin_lock_irqsave(&fh->vdev->fh_lock, flags);
- if (v4l2_event_subscribed(fh, sub->type) == NULL) {
+ found_ev = v4l2_event_subscribed(fh, sub->type, sub->id);
+ if (!found_ev) {
INIT_LIST_HEAD(&sev->list);
sev->type = sub->type;
+ sev->id = sub->id;
list_add(&sev->list, &events->subscribed);
sev = NULL;
@@ -247,6 +290,10 @@ int v4l2_event_subscribe(struct v4l2_fh *fh,
spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
+ /* v4l2_ctrl_add_fh uses a mutex, so do this outside the spin lock */
+ if (!found_ev && ctrl)
+ v4l2_ctrl_add_fh(ctrl, ctrl_fh);
+
kfree(sev);
return 0;
@@ -256,6 +303,7 @@ EXPORT_SYMBOL_GPL(v4l2_event_subscribe);
static void v4l2_event_unsubscribe_all(struct v4l2_fh *fh)
{
struct v4l2_events *events = fh->events;
+ struct v4l2_event_subscription sub;
struct v4l2_subscribed_event *sev;
unsigned long flags;
@@ -265,11 +313,13 @@ static void v4l2_event_unsubscribe_all(struct v4l2_fh *fh)
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);
+ struct v4l2_subscribed_event, list);
+ sub.type = sev->type;
+ sub.id = sev->id;
}
spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
- kfree(sev);
+ if (sev)
+ v4l2_event_unsubscribe(fh, &sub);
} while (sev);
}
@@ -286,11 +336,17 @@ int v4l2_event_unsubscribe(struct v4l2_fh *fh,
spin_lock_irqsave(&fh->vdev->fh_lock, flags);
- sev = v4l2_event_subscribed(fh, sub->type);
+ sev = v4l2_event_subscribed(fh, sub->type, sub->id);
if (sev != NULL)
list_del(&sev->list);
spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
+ if (sev->type == V4L2_EVENT_CTRL_CH_VALUE) {
+ struct v4l2_ctrl *ctrl = v4l2_ctrl_find(fh->ctrl_handler, sev->id);
+
+ if (ctrl)
+ v4l2_ctrl_del_fh(ctrl, fh);
+ }
kfree(sev);
diff --git a/drivers/media/video/v4l2-fh.c b/drivers/media/video/v4l2-fh.c
index 8635011..c6aef84 100644
--- a/drivers/media/video/v4l2-fh.c
+++ b/drivers/media/video/v4l2-fh.c
@@ -93,10 +93,8 @@ void v4l2_fh_exit(struct v4l2_fh *fh)
{
if (fh->vdev == NULL)
return;
-
- fh->vdev = NULL;
-
v4l2_event_free(fh);
+ fh->vdev = NULL;
}
EXPORT_SYMBOL_GPL(v4l2_fh_exit);
diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h
index 92d2fdd..f7238c1 100644
--- a/include/linux/videodev2.h
+++ b/include/linux/videodev2.h
@@ -1787,6 +1787,7 @@ struct v4l2_streamparm {
#define V4L2_EVENT_ALL 0
#define V4L2_EVENT_VSYNC 1
#define V4L2_EVENT_EOS 2
+#define V4L2_EVENT_CTRL_CH_VALUE 3
#define V4L2_EVENT_PRIVATE_START 0x08000000
/* Payload for V4L2_EVENT_VSYNC */
@@ -1795,21 +1796,33 @@ struct v4l2_event_vsync {
__u8 field;
} __attribute__ ((packed));
+/* Payload for V4L2_EVENT_CTRL_CH_VALUE */
+struct v4l2_event_ctrl_ch_value {
+ __u32 type;
+ union {
+ __s32 value;
+ __s64 value64;
+ };
+} __attribute__ ((packed));
+
struct v4l2_event {
__u32 type;
union {
struct v4l2_event_vsync vsync;
+ struct v4l2_event_ctrl_ch_value ctrl_ch_value;
__u8 data[64];
} u;
__u32 pending;
__u32 sequence;
struct timespec timestamp;
- __u32 reserved[9];
+ __u32 id;
+ __u32 reserved[8];
};
struct v4l2_event_subscription {
__u32 type;
- __u32 reserved[7];
+ __u32 id;
+ __u32 reserved[6];
};
/*
diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h
index 97d0638..7ca45a5 100644
--- a/include/media/v4l2-ctrls.h
+++ b/include/media/v4l2-ctrls.h
@@ -30,6 +30,7 @@ struct v4l2_ctrl_handler;
struct v4l2_ctrl;
struct video_device;
struct v4l2_subdev;
+struct v4l2_fh;
/** struct v4l2_ctrl_ops - The control operations that the driver has to provide.
* @g_volatile_ctrl: Get a new value for this control. Generally only relevant
@@ -97,6 +98,7 @@ struct v4l2_ctrl_ops {
struct v4l2_ctrl {
/* Administrative fields */
struct list_head node;
+ struct list_head fhs;
struct v4l2_ctrl_handler *handler;
struct v4l2_ctrl **cluster;
unsigned ncontrols;
@@ -168,6 +170,11 @@ struct v4l2_ctrl_handler {
int error;
};
+struct v4l2_ctrl_fh {
+ struct list_head node;
+ struct v4l2_fh *fh;
+};
+
/** struct v4l2_ctrl_config - Control configuration structure.
* @ops: The control ops.
* @id: The control ID.
@@ -440,6 +447,8 @@ s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl);
*/
int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val);
+void v4l2_ctrl_add_fh(struct v4l2_ctrl *ctrl, struct v4l2_ctrl_fh *ctrl_fh);
+void v4l2_ctrl_del_fh(struct v4l2_ctrl *ctrl, struct v4l2_fh *fh);
/* Helpers for ioctl_ops. If hdl == NULL then they will all return -EINVAL. */
int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc);
diff --git a/include/media/v4l2-event.h b/include/media/v4l2-event.h
index 3b86177..45e9c1e 100644
--- a/include/media/v4l2-event.h
+++ b/include/media/v4l2-event.h
@@ -40,6 +40,7 @@ struct v4l2_kevent {
struct v4l2_subscribed_event {
struct list_head list;
u32 type;
+ u32 id;
};
struct v4l2_events {
@@ -58,6 +59,7 @@ 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);
+void v4l2_event_queue_fh(struct v4l2_fh *fh, 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);
--
1.7.1
--
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