Commit 173f6eac authored by Ezequiel Garcia's avatar Ezequiel Garcia Committed by Mauro Carvalho Chehab
Browse files

media: v4l: ctrls: Add debug messages 



Currently, the v4l2 control code is a bit silent on errors.
Add debug messages on (hopefully) most of the error paths.

Signed-off-by: default avatarEzequiel Garcia <ezequiel@collabora.com>
Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+samsung@kernel.org>
parent d4a6a953

Documentation/media/kapi/v4l2-dev.rst

+1 −0
Original line number Diff line number Diff line
@@ -288,6 +288,7 @@ Mask Description 
0x08  Log the read and write file operations and the VIDIOC_QBUF and

      VIDIOC_DQBUF ioctls.

0x10  Log the poll file operation.

0x20  Log error and messages in the control operations.

===== ================================================================



Video device cleanup

drivers/media/platform/omap3isp/ispvideo.c

+2 −2
Original line number Diff line number Diff line
@@ -1020,8 +1020,8 @@ static int isp_video_check_external_subdevs(struct isp_video *video, 


	ctrls.count = 1;

	ctrls.controls = &ctrl;



	ret = v4l2_g_ext_ctrls(pipe->external->ctrl_handler, NULL, &ctrls);

	ret = v4l2_g_ext_ctrls(pipe->external->ctrl_handler, &video->video,

			       NULL, &ctrls);

	if (ret < 0) {

		dev_warn(isp->dev, "no pixel rate control in subdev %s\n",

			 pipe->external->name);

drivers/media/v4l2-core/v4l2-ctrls.c

+100 −26
Original line number Diff line number Diff line
@@ -6,6 +6,8 @@ 


 */



#define pr_fmt(fmt) "v4l2-ctrls: " fmt



#include <linux/ctype.h>

#include <linux/mm.h>

#include <linux/slab.h>
@@ -16,6 +18,12 @@ 
#include <media/v4l2-event.h>

#include <media/v4l2-dev.h>



#define dprintk(vdev, fmt, arg...) do {					\

	if (!WARN_ON(!(vdev)) && ((vdev)->dev_debug & V4L2_DEV_DEBUG_CTRL)) \

		printk(KERN_DEBUG pr_fmt("%s: %s: " fmt),		\

		       __func__, video_device_node_name(vdev), ##arg);	\

} while (0)



#define has_op(master, op) \

	(master->ops && master->ops->op)

#define call_op(master, op) \
@@ -3260,6 +3268,7 @@ static int v4l2_ctrl_request_bind(struct media_request *req, 
static int prepare_ext_ctrls(struct v4l2_ctrl_handler *hdl,

			     struct v4l2_ext_controls *cs,

			     struct v4l2_ctrl_helper *helpers,

			     struct video_device *vdev,

			     bool get)

{

	struct v4l2_ctrl_helper *h;
@@ -3277,20 +3286,31 @@ static int prepare_ext_ctrls(struct v4l2_ctrl_handler *hdl, 
		if (cs->which &&

		    cs->which != V4L2_CTRL_WHICH_DEF_VAL &&

		    cs->which != V4L2_CTRL_WHICH_REQUEST_VAL &&

		    V4L2_CTRL_ID2WHICH(id) != cs->which)

		    V4L2_CTRL_ID2WHICH(id) != cs->which) {

			dprintk(vdev,

				"invalid which 0x%x or control id 0x%x\n",

				cs->which, id);

			return -EINVAL;

		}



		/* Old-style private controls are not allowed for

		   extended controls */

		if (id >= V4L2_CID_PRIVATE_BASE)

		if (id >= V4L2_CID_PRIVATE_BASE) {

			dprintk(vdev,

				"old-style private controls not allowed\n");

			return -EINVAL;

		}

		ref = find_ref_lock(hdl, id);

		if (ref == NULL)

		if (ref == NULL) {

			dprintk(vdev, "cannot find control id 0x%x\n", id);

			return -EINVAL;

		}

		h->ref = ref;

		ctrl = ref->ctrl;

		if (ctrl->flags & V4L2_CTRL_FLAG_DISABLED)

		if (ctrl->flags & V4L2_CTRL_FLAG_DISABLED) {

			dprintk(vdev, "control id 0x%x is disabled\n", id);

			return -EINVAL;

		}



		if (ctrl->cluster[0]->ncontrols > 1)

			have_clusters = true;
@@ -3300,10 +3320,17 @@ static int prepare_ext_ctrls(struct v4l2_ctrl_handler *hdl, 
			unsigned tot_size = ctrl->elems * ctrl->elem_size;



			if (c->size < tot_size) {

				/*

				 * In the get case the application first

				 * queries to obtain the size of the control.

				 */

				if (get) {

					c->size = tot_size;

					return -ENOSPC;

				}

				dprintk(vdev,

					"pointer control id 0x%x size too small, %d bytes but %d bytes needed\n",

					id, c->size, tot_size);

				return -EFAULT;

			}

			c->size = tot_size;
@@ -3364,7 +3391,8 @@ static int class_check(struct v4l2_ctrl_handler *hdl, u32 which) 


/* Get extended controls. Allocates the helpers array if needed. */

static int v4l2_g_ext_ctrls_common(struct v4l2_ctrl_handler *hdl,

				   struct v4l2_ext_controls *cs)

				   struct v4l2_ext_controls *cs,

				   struct video_device *vdev)

{

	struct v4l2_ctrl_helper helper[4];

	struct v4l2_ctrl_helper *helpers = helper;
@@ -3390,7 +3418,7 @@ static int v4l2_g_ext_ctrls_common(struct v4l2_ctrl_handler *hdl, 
			return -ENOMEM;

	}



	ret = prepare_ext_ctrls(hdl, cs, helpers, true);

	ret = prepare_ext_ctrls(hdl, cs, helpers, vdev, true);

	cs->error_idx = cs->count;



	for (i = 0; !ret && i < cs->count; i++)
@@ -3483,8 +3511,8 @@ v4l2_ctrls_find_req_obj(struct v4l2_ctrl_handler *hdl, 
	return obj;

}



int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct media_device *mdev,

		     struct v4l2_ext_controls *cs)

int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct video_device *vdev,

		     struct media_device *mdev, struct v4l2_ext_controls *cs)

{

	struct media_request_object *obj = NULL;

	struct media_request *req = NULL;
@@ -3520,7 +3548,7 @@ int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct media_device *mdev, 
				   req_obj);

	}



	ret = v4l2_g_ext_ctrls_common(hdl, cs);

	ret = v4l2_g_ext_ctrls_common(hdl, cs, vdev);



	if (obj) {

		media_request_unlock_for_access(req);
@@ -3663,7 +3691,9 @@ static int try_or_set_cluster(struct v4l2_fh *fh, struct v4l2_ctrl *master, 


/* Validate controls. */

static int validate_ctrls(struct v4l2_ext_controls *cs,

			  struct v4l2_ctrl_helper *helpers, bool set)

			  struct v4l2_ctrl_helper *helpers,

			  struct video_device *vdev,

			  bool set)

{

	unsigned i;

	int ret = 0;
@@ -3675,16 +3705,24 @@ static int validate_ctrls(struct v4l2_ext_controls *cs, 


		cs->error_idx = i;



		if (ctrl->flags & V4L2_CTRL_FLAG_READ_ONLY)

		if (ctrl->flags & V4L2_CTRL_FLAG_READ_ONLY) {

			dprintk(vdev,

				"control id 0x%x is read-only\n",

				ctrl->id);

			return -EACCES;

		}

		/* This test is also done in try_set_control_cluster() which

		   is called in atomic context, so that has the final say,

		   but it makes sense to do an up-front check as well. Once

		   an error occurs in try_set_control_cluster() some other

		   controls may have been set already and we want to do a

		   best-effort to avoid that. */

		if (set && (ctrl->flags & V4L2_CTRL_FLAG_GRABBED))

		if (set && (ctrl->flags & V4L2_CTRL_FLAG_GRABBED)) {

			dprintk(vdev,

				"control id 0x%x is grabbed, cannot set\n",

				ctrl->id);

			return -EBUSY;

		}

		/*

		 * Skip validation for now if the payload needs to be copied

		 * from userspace into kernelspace. We'll validate those later.
@@ -3719,7 +3757,8 @@ static void update_from_auto_cluster(struct v4l2_ctrl *master) 
/* Try or try-and-set controls */

static int try_set_ext_ctrls_common(struct v4l2_fh *fh,

				    struct v4l2_ctrl_handler *hdl,

				    struct v4l2_ext_controls *cs, bool set)

				    struct v4l2_ext_controls *cs,

				    struct video_device *vdev, bool set)

{

	struct v4l2_ctrl_helper helper[4];

	struct v4l2_ctrl_helper *helpers = helper;
@@ -3729,13 +3768,19 @@ static int try_set_ext_ctrls_common(struct v4l2_fh *fh, 
	cs->error_idx = cs->count;



	/* Default value cannot be changed */

	if (cs->which == V4L2_CTRL_WHICH_DEF_VAL)

	if (cs->which == V4L2_CTRL_WHICH_DEF_VAL) {

		dprintk(vdev, "%s: cannot change default value\n",

			video_device_node_name(vdev));

		return -EINVAL;

	}



	cs->which = V4L2_CTRL_ID2WHICH(cs->which);



	if (hdl == NULL)

	if (hdl == NULL) {

		dprintk(vdev, "%s: invalid null control handler\n",

			video_device_node_name(vdev));

		return -EINVAL;

	}



	if (cs->count == 0)

		return class_check(hdl, cs->which);
@@ -3746,9 +3791,9 @@ static int try_set_ext_ctrls_common(struct v4l2_fh *fh, 
		if (!helpers)

			return -ENOMEM;

	}

	ret = prepare_ext_ctrls(hdl, cs, helpers, false);

	ret = prepare_ext_ctrls(hdl, cs, helpers, vdev, false);

	if (!ret)

		ret = validate_ctrls(cs, helpers, set);

		ret = validate_ctrls(cs, helpers, vdev, set);

	if (ret && set)

		cs->error_idx = cs->count;

	for (i = 0; !ret && i < cs->count; i++) {
@@ -3833,7 +3878,9 @@ static int try_set_ext_ctrls_common(struct v4l2_fh *fh, 
}



static int try_set_ext_ctrls(struct v4l2_fh *fh,

			     struct v4l2_ctrl_handler *hdl, struct media_device *mdev,

			     struct v4l2_ctrl_handler *hdl,

			     struct video_device *vdev,

			     struct media_device *mdev,

			     struct v4l2_ext_controls *cs, bool set)

{

	struct media_request_object *obj = NULL;
@@ -3841,21 +3888,39 @@ static int try_set_ext_ctrls(struct v4l2_fh *fh, 
	int ret;



	if (cs->which == V4L2_CTRL_WHICH_REQUEST_VAL) {

		if (!mdev || cs->request_fd < 0)

		if (!mdev) {

			dprintk(vdev, "%s: missing media device\n",

				video_device_node_name(vdev));

			return -EINVAL;

		}



		if (cs->request_fd < 0) {

			dprintk(vdev, "%s: invalid request fd %d\n",

				video_device_node_name(vdev), cs->request_fd);

			return -EINVAL;

		}



		req = media_request_get_by_fd(mdev, cs->request_fd);

		if (IS_ERR(req))

		if (IS_ERR(req)) {

			dprintk(vdev, "%s: cannot find request fd %d\n",

				video_device_node_name(vdev), cs->request_fd);

			return PTR_ERR(req);

		}



		ret = media_request_lock_for_update(req);

		if (ret) {

			dprintk(vdev, "%s: cannot lock request fd %d\n",

				video_device_node_name(vdev), cs->request_fd);

			media_request_put(req);

			return ret;

		}



		obj = v4l2_ctrls_find_req_obj(hdl, req, set);

		if (IS_ERR(obj)) {

			dprintk(vdev,

				"%s: cannot find request object for request fd %d\n",

				video_device_node_name(vdev),

				cs->request_fd);

			media_request_unlock_for_update(req);

			media_request_put(req);

			return PTR_ERR(obj);
@@ -3864,7 +3929,11 @@ static int try_set_ext_ctrls(struct v4l2_fh *fh, 
				   req_obj);

	}



	ret = try_set_ext_ctrls_common(fh, hdl, cs, set);

	ret = try_set_ext_ctrls_common(fh, hdl, cs, vdev, set);

	if (ret)

		dprintk(vdev,

			"%s: try_set_ext_ctrls_common failed (%d)\n",

			video_device_node_name(vdev), ret);



	if (obj) {

		media_request_unlock_for_update(req);
@@ -3875,17 +3944,22 @@ static int try_set_ext_ctrls(struct v4l2_fh *fh, 
	return ret;

}



int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct media_device *mdev,

int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl,

		       struct video_device *vdev,

		       struct media_device *mdev,

		       struct v4l2_ext_controls *cs)

{

	return try_set_ext_ctrls(NULL, hdl, mdev, cs, false);

	return try_set_ext_ctrls(NULL, hdl, vdev, mdev, cs, false);

}

EXPORT_SYMBOL(v4l2_try_ext_ctrls);



int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,

		     struct media_device *mdev, struct v4l2_ext_controls *cs)

int v4l2_s_ext_ctrls(struct v4l2_fh *fh,

		     struct v4l2_ctrl_handler *hdl,

		     struct video_device *vdev,

		     struct media_device *mdev,

		     struct v4l2_ext_controls *cs)

{

	return try_set_ext_ctrls(fh, hdl, mdev, cs, true);

	return try_set_ext_ctrls(fh, hdl, vdev, mdev, cs, true);

}

EXPORT_SYMBOL(v4l2_s_ext_ctrls);

drivers/media/v4l2-core/v4l2-ioctl.c

+12 −6
Original line number Diff line number Diff line
@@ -2186,9 +2186,11 @@ static int v4l_g_ext_ctrls(const struct v4l2_ioctl_ops *ops, 


	p->error_idx = p->count;

	if (vfh && vfh->ctrl_handler)

		return v4l2_g_ext_ctrls(vfh->ctrl_handler, vfd->v4l2_dev->mdev, p);

		return v4l2_g_ext_ctrls(vfh->ctrl_handler,

					vfd, vfd->v4l2_dev->mdev, p);

	if (vfd->ctrl_handler)

		return v4l2_g_ext_ctrls(vfd->ctrl_handler, vfd->v4l2_dev->mdev, p);

		return v4l2_g_ext_ctrls(vfd->ctrl_handler,

					vfd, vfd->v4l2_dev->mdev, p);

	if (ops->vidioc_g_ext_ctrls == NULL)

		return -ENOTTY;

	return check_ext_ctrls(p, 0) ? ops->vidioc_g_ext_ctrls(file, fh, p) :
@@ -2205,9 +2207,11 @@ static int v4l_s_ext_ctrls(const struct v4l2_ioctl_ops *ops, 


	p->error_idx = p->count;

	if (vfh && vfh->ctrl_handler)

		return v4l2_s_ext_ctrls(vfh, vfh->ctrl_handler, vfd->v4l2_dev->mdev, p);

		return v4l2_s_ext_ctrls(vfh, vfh->ctrl_handler,

					vfd, vfd->v4l2_dev->mdev, p);

	if (vfd->ctrl_handler)

		return v4l2_s_ext_ctrls(NULL, vfd->ctrl_handler, vfd->v4l2_dev->mdev, p);

		return v4l2_s_ext_ctrls(NULL, vfd->ctrl_handler,

					vfd, vfd->v4l2_dev->mdev, p);

	if (ops->vidioc_s_ext_ctrls == NULL)

		return -ENOTTY;

	return check_ext_ctrls(p, 0) ? ops->vidioc_s_ext_ctrls(file, fh, p) :
@@ -2224,9 +2228,11 @@ static int v4l_try_ext_ctrls(const struct v4l2_ioctl_ops *ops, 


	p->error_idx = p->count;

	if (vfh && vfh->ctrl_handler)

		return v4l2_try_ext_ctrls(vfh->ctrl_handler, vfd->v4l2_dev->mdev, p);

		return v4l2_try_ext_ctrls(vfh->ctrl_handler,

					  vfd, vfd->v4l2_dev->mdev, p);

	if (vfd->ctrl_handler)

		return v4l2_try_ext_ctrls(vfd->ctrl_handler, vfd->v4l2_dev->mdev, p);

		return v4l2_try_ext_ctrls(vfd->ctrl_handler,

					  vfd, vfd->v4l2_dev->mdev, p);

	if (ops->vidioc_try_ext_ctrls == NULL)

		return -ENOTTY;

	return check_ext_ctrls(p, 0) ? ops->vidioc_try_ext_ctrls(file, fh, p) :

drivers/media/v4l2-core/v4l2-subdev.c

+3 −3
Original line number Diff line number Diff line
@@ -372,19 +372,19 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg) 
		if (!vfh->ctrl_handler)

			return -ENOTTY;

		return v4l2_g_ext_ctrls(vfh->ctrl_handler,

					sd->v4l2_dev->mdev, arg);

					vdev, sd->v4l2_dev->mdev, arg);



	case VIDIOC_S_EXT_CTRLS:

		if (!vfh->ctrl_handler)

			return -ENOTTY;

		return v4l2_s_ext_ctrls(vfh, vfh->ctrl_handler,

					sd->v4l2_dev->mdev, arg);

					vdev, sd->v4l2_dev->mdev, arg);



	case VIDIOC_TRY_EXT_CTRLS:

		if (!vfh->ctrl_handler)

			return -ENOTTY;

		return v4l2_try_ext_ctrls(vfh->ctrl_handler,

					  sd->v4l2_dev->mdev, arg);

					  vdev, sd->v4l2_dev->mdev, arg);



	case VIDIOC_DQEVENT:

		if (!(sd->flags & V4L2_SUBDEV_FL_HAS_EVENTS))