[media] v4l2-ctrls: add a filter function to v4l2_ctrl_add_handler

With a filter function you can control more precisely which controls
are added. This is useful in particular for radio device nodes for
combined TV/Radio cards where you want to show just the radio-specific
controls and not controls like brightness.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Hans Verkuil 2012-09-14 07:15:03 -03:00 committed by Mauro Carvalho Chehab
parent a4f64407b9
commit 34a6b7d093
8 changed files with 50 additions and 9 deletions

View file

@ -594,7 +594,11 @@ handler and finally add the first handler to the second. For example:
v4l2_ctrl_new_std(&radio_ctrl_handler, &radio_ops, V4L2_CID_AUDIO_MUTE, ...);
v4l2_ctrl_new_std(&video_ctrl_handler, &video_ops, V4L2_CID_BRIGHTNESS, ...);
v4l2_ctrl_new_std(&video_ctrl_handler, &video_ops, V4L2_CID_CONTRAST, ...);
v4l2_ctrl_add_handler(&video_ctrl_handler, &radio_ctrl_handler);
v4l2_ctrl_add_handler(&video_ctrl_handler, &radio_ctrl_handler, NULL);
The last argument to v4l2_ctrl_add_handler() is a filter function that allows
you to filter which controls will be added. Set it to NULL if you want to add
all controls.
Or you can add specific controls to a handler:

View file

@ -1236,7 +1236,7 @@ static int cx8802_blackbird_probe(struct cx8802_driver *drv)
err = cx2341x_handler_init(&dev->cxhdl, 36);
if (err)
goto fail_core;
v4l2_ctrl_add_handler(&dev->cxhdl.hdl, &core->video_hdl);
v4l2_ctrl_add_handler(&dev->cxhdl.hdl, &core->video_hdl, NULL);
/* blackbird stuff */
printk("%s/2: cx23416 based mpeg encoder (blackbird reference design)\n",

View file

@ -1795,7 +1795,7 @@ static int __devinit cx8800_initdev(struct pci_dev *pci_dev,
if (vc->id == V4L2_CID_CHROMA_AGC)
core->chroma_agc = vc;
}
v4l2_ctrl_add_handler(&core->video_hdl, &core->audio_hdl);
v4l2_ctrl_add_handler(&core->video_hdl, &core->audio_hdl, NULL);
/* load and configure helper modules */

View file

@ -472,7 +472,7 @@ int fimc_capture_ctrls_create(struct fimc_dev *fimc)
return ret;
return v4l2_ctrl_add_handler(&vid_cap->ctx->ctrls.handler,
fimc->pipeline.subdevs[IDX_SENSOR]->ctrl_handler);
fimc->pipeline.subdevs[IDX_SENSOR]->ctrl_handler, NULL);
}
static int fimc_capture_set_default_format(struct fimc_dev *fimc);

View file

@ -1184,7 +1184,7 @@ static int soc_camera_probe(struct soc_camera_device *icd)
sd->grp_id = soc_camera_grp_id(icd);
v4l2_set_subdev_hostdata(sd, icd);
if (v4l2_ctrl_add_handler(&icd->ctrl_handler, sd->ctrl_handler))
if (v4l2_ctrl_add_handler(&icd->ctrl_handler, sd->ctrl_handler, NULL))
goto ectrl;
/* At this point client .probe() should have run already */

View file

@ -1687,7 +1687,8 @@ EXPORT_SYMBOL(v4l2_ctrl_add_ctrl);
/* Add the controls from another handler to our own. */
int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
struct v4l2_ctrl_handler *add)
struct v4l2_ctrl_handler *add,
bool (*filter)(const struct v4l2_ctrl *ctrl))
{
struct v4l2_ctrl_ref *ref;
int ret = 0;
@ -1707,6 +1708,9 @@ int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
/* And control classes */
if (ctrl->type == V4L2_CTRL_TYPE_CTRL_CLASS)
continue;
/* Filter any unwanted controls */
if (filter && !filter(ctrl))
continue;
ret = handler_new_ref(hdl, ctrl);
if (ret)
break;
@ -1716,6 +1720,25 @@ int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
}
EXPORT_SYMBOL(v4l2_ctrl_add_handler);
bool v4l2_ctrl_radio_filter(const struct v4l2_ctrl *ctrl)
{
if (V4L2_CTRL_ID2CLASS(ctrl->id) == V4L2_CTRL_CLASS_FM_TX)
return true;
switch (ctrl->id) {
case V4L2_CID_AUDIO_MUTE:
case V4L2_CID_AUDIO_VOLUME:
case V4L2_CID_AUDIO_BALANCE:
case V4L2_CID_AUDIO_BASS:
case V4L2_CID_AUDIO_TREBLE:
case V4L2_CID_AUDIO_LOUDNESS:
return true;
default:
break;
}
return false;
}
EXPORT_SYMBOL(v4l2_ctrl_radio_filter);
/* Cluster controls */
void v4l2_ctrl_cluster(unsigned ncontrols, struct v4l2_ctrl **controls)
{

View file

@ -166,7 +166,7 @@ int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
}
/* This just returns 0 if either of the two args is NULL */
err = v4l2_ctrl_add_handler(v4l2_dev->ctrl_handler, sd->ctrl_handler);
err = v4l2_ctrl_add_handler(v4l2_dev->ctrl_handler, sd->ctrl_handler, NULL);
if (err) {
if (sd->internal_ops && sd->internal_ops->unregistered)
sd->internal_ops->unregistered(sd);

View file

@ -384,14 +384,28 @@ struct v4l2_ctrl *v4l2_ctrl_add_ctrl(struct v4l2_ctrl_handler *hdl,
* @hdl: The control handler.
* @add: The control handler whose controls you want to add to
* the @hdl control handler.
* @filter: This function will filter which controls should be added.
*
* Does nothing if either of the two is a NULL pointer.
* Does nothing if either of the two handlers is a NULL pointer.
* If @filter is NULL, then all controls are added. Otherwise only those
* controls for which @filter returns true will be added.
* In case of an error @hdl->error will be set to the error code (if it
* wasn't set already).
*/
int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
struct v4l2_ctrl_handler *add);
struct v4l2_ctrl_handler *add,
bool (*filter)(const struct v4l2_ctrl *ctrl));
/** v4l2_ctrl_radio_filter() - Standard filter for radio controls.
* @ctrl: The control that is filtered.
*
* This will return true for any controls that are valid for radio device
* nodes. Those are all of the V4L2_CID_AUDIO_* user controls and all FM
* transmitter class controls.
*
* This function is to be used with v4l2_ctrl_add_handler().
*/
bool v4l2_ctrl_radio_filter(const struct v4l2_ctrl *ctrl);
/** v4l2_ctrl_cluster() - Mark all controls in the cluster as belonging to that cluster.
* @ncontrols: The number of controls in this cluster.