[PATCH 10/10] uvcvideo: Send control change events for slave ctrls when the master changes

Hans de Goede
2012-03-25T11:55:02Z

This allows v4l2 control UI-s to update the inactive state (ie grey-ing
out of controls) for slave controls when the master control changes.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
drivers/media/video/uvc/uvc_ctrl.c | 55 ++++++++++++++++++++++++++++++++++--
1 file changed, 52 insertions(+), 3 deletions(-)

diff --git a/drivers/media/video/uvc/uvc_ctrl.c b/drivers/media/video/uvc/uvc_ctrl.c
index 91d9007..2d06fd8 100644
--- a/drivers/media/video/uvc/uvc_ctrl.c
+++ b/drivers/media/video/uvc/uvc_ctrl.c
@@ -1179,21 +1179,70 @@ static void uvc_ctrl_send_event(struct uvc_fh *handle,

list_for_each_entry(sev, &mapping->ev_subs, node)
if (sev->fh && (sev->fh != &handle->vfh ||
- (sev->flags & V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK)))
+ (sev->flags & V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK) ||
+ (changes & V4L2_EVENT_CTRL_CH_FLAGS)))
v4l2_event_queue_fh(sev->fh, &ev);
}

-static void uvc_ctrl_send_events(struct uvc_fh *handle,
+static void uvc_ctrl_send_slave_event(struct uvc_fh *handle, u32 slave_id,
struct v4l2_ext_control *xctrls, int xctrls_count)
{
struct uvc_control_mapping *mapping;
struct uvc_control *ctrl;
+ u32 changes = V4L2_EVENT_CTRL_CH_FLAGS;
+ s32 val = 0;
int i;

+ /*
+ * We can skip sending an event for the slave if the slave
+ * is being modified in the same transaction.
+ */
+ for (i = 0; i < xctrls_count; i++)
+ if (xctrls[i].id == slave_id)
+ return;
+
+ ctrl = uvc_find_control(handle->chain, slave_id, &mapping);
+ if (ctrl == NULL)
+ return;
+
+ if (__uvc_ctrl_get(handle->chain, ctrl, mapping, &val) == 0)
+ changes |= V4L2_EVENT_CTRL_CH_VALUE;
+
+ uvc_ctrl_send_event(handle, ctrl, mapping, val, changes);
+}
+
+static void uvc_ctrl_send_events(struct uvc_fh *handle,
+ struct v4l2_ext_control *xctrls, int xctrls_count)
+{
+ struct uvc_control_mapping *mapping;
+ struct uvc_control *ctrl;
+ u32 changes = V4L2_EVENT_CTRL_CH_VALUE;
+ int i, j;
+
for (i = 0; i < xctrls_count; ++i) {
ctrl = uvc_find_control(handle->chain, xctrls[i].id, &mapping);
+
+ for (j = 0; j < ARRAY_SIZE(mapping->slave_ids); ++j) {
+ if (!mapping->slave_ids[j])
+ break;
+ uvc_ctrl_send_slave_event(handle,
+ mapping->slave_ids[j],
+ xctrls, xctrls_count);
+ }
+
+ /*
+ * If the master is being modified in the same transaction
+ * flags may change too.
+ */
+ if (mapping->master_id)
+ for (j = 0; j < xctrls_count; j++)
+ if (xctrls[j].id == mapping->master_id) {
+ changes |= V4L2_EVENT_CTRL_CH_FLAGS;
+ break;
+ }
+
uvc_ctrl_send_event(handle, ctrl, mapping, xctrls[i].value,
- V4L2_EVENT_CTRL_CH_VALUE);
+ changes);
}
}

--
1.7.9.3