[media] v4l2 core: improve debug flag handling
The old debug field is renamed to dev_debug to ensure that existing drivers
(including out-of-tree drivers) that try to use the old name will no longer
compile. A comment has also been added that makes it explicit that drivers
shouldn't use this field.
Additional bits have been added to the debug flag to be more fine-grained
when debugging, especially when dealing with streaming ioctls and read,
write and poll. You want to enable those explicitly to prevent flooding
the log when streaming unless you actually want to do that.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
index a13cc61..86bb93f 100644
--- a/drivers/media/v4l2-core/v4l2-dev.c
+++ b/drivers/media/v4l2-core/v4l2-dev.c
@@ -47,15 +47,15 @@
}
static DEVICE_ATTR_RO(index);
-static ssize_t debug_show(struct device *cd,
+static ssize_t dev_debug_show(struct device *cd,
struct device_attribute *attr, char *buf)
{
struct video_device *vdev = to_video_device(cd);
- return sprintf(buf, "%i\n", vdev->debug);
+ return sprintf(buf, "%i\n", vdev->dev_debug);
}
-static ssize_t debug_store(struct device *cd, struct device_attribute *attr,
+static ssize_t dev_debug_store(struct device *cd, struct device_attribute *attr,
const char *buf, size_t len)
{
struct video_device *vdev = to_video_device(cd);
@@ -66,10 +66,10 @@
if (res)
return res;
- vdev->debug = value;
+ vdev->dev_debug = value;
return len;
}
-static DEVICE_ATTR_RW(debug);
+static DEVICE_ATTR_RW(dev_debug);
static ssize_t name_show(struct device *cd,
struct device_attribute *attr, char *buf)
@@ -82,7 +82,7 @@
static struct attribute *video_device_attrs[] = {
&dev_attr_name.attr,
- &dev_attr_debug.attr,
+ &dev_attr_dev_debug.attr,
&dev_attr_index.attr,
NULL,
};
@@ -304,7 +304,8 @@
return -EINVAL;
if (video_is_registered(vdev))
ret = vdev->fops->read(filp, buf, sz, off);
- if (vdev->debug)
+ if ((vdev->dev_debug & V4L2_DEV_DEBUG_FOP) &&
+ (vdev->dev_debug & V4L2_DEV_DEBUG_STREAMING))
printk(KERN_DEBUG "%s: read: %zd (%d)\n",
video_device_node_name(vdev), sz, ret);
return ret;
@@ -320,7 +321,8 @@
return -EINVAL;
if (video_is_registered(vdev))
ret = vdev->fops->write(filp, buf, sz, off);
- if (vdev->debug)
+ if ((vdev->dev_debug & V4L2_DEV_DEBUG_FOP) &&
+ (vdev->dev_debug & V4L2_DEV_DEBUG_STREAMING))
printk(KERN_DEBUG "%s: write: %zd (%d)\n",
video_device_node_name(vdev), sz, ret);
return ret;
@@ -335,7 +337,7 @@
return DEFAULT_POLLMASK;
if (video_is_registered(vdev))
res = vdev->fops->poll(filp, poll);
- if (vdev->debug > 2)
+ if (vdev->dev_debug & V4L2_DEV_DEBUG_POLL)
printk(KERN_DEBUG "%s: poll: %08x\n",
video_device_node_name(vdev), res);
return res;
@@ -404,7 +406,7 @@
if (!video_is_registered(vdev))
return -ENODEV;
ret = vdev->fops->get_unmapped_area(filp, addr, len, pgoff, flags);
- if (vdev->debug)
+ if (vdev->dev_debug & V4L2_DEV_DEBUG_FOP)
printk(KERN_DEBUG "%s: get_unmapped_area (%d)\n",
video_device_node_name(vdev), ret);
return ret;
@@ -420,7 +422,7 @@
return -ENODEV;
if (video_is_registered(vdev))
ret = vdev->fops->mmap(filp, vm);
- if (vdev->debug)
+ if (vdev->dev_debug & V4L2_DEV_DEBUG_FOP)
printk(KERN_DEBUG "%s: mmap (%d)\n",
video_device_node_name(vdev), ret);
return ret;
@@ -450,7 +452,7 @@
ret = -ENODEV;
}
- if (vdev->debug)
+ if (vdev->dev_debug & V4L2_DEV_DEBUG_FOP)
printk(KERN_DEBUG "%s: open (%d)\n",
video_device_node_name(vdev), ret);
/* decrease the refcount in case of an error */
@@ -467,7 +469,7 @@
if (vdev->fops->release)
ret = vdev->fops->release(filp);
- if (vdev->debug)
+ if (vdev->dev_debug & V4L2_DEV_DEBUG_FOP)
printk(KERN_DEBUG "%s: release\n",
video_device_node_name(vdev));
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index faac2f4..b084072 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -2339,7 +2339,7 @@
const struct v4l2_ioctl_info *info;
void *fh = file->private_data;
struct v4l2_fh *vfh = NULL;
- int debug = vfd->debug;
+ int dev_debug = vfd->dev_debug;
long ret = -ENOTTY;
if (ops == NULL) {
@@ -2388,11 +2388,15 @@
}
done:
- if (debug) {
+ if (dev_debug & (V4L2_DEV_DEBUG_IOCTL | V4L2_DEV_DEBUG_IOCTL_ARG)) {
+ if (!(dev_debug & V4L2_DEV_DEBUG_STREAMING) &&
+ (cmd == VIDIOC_QBUF || cmd == VIDIOC_DQBUF))
+ return ret;
+
v4l_printk_ioctl(video_device_node_name(vfd), cmd);
if (ret < 0)
pr_cont(": error %ld", ret);
- if (debug == V4L2_DEBUG_IOCTL)
+ if (!(dev_debug & V4L2_DEV_DEBUG_IOCTL_ARG))
pr_cont("\n");
else if (_IOC_DIR(cmd) == _IOC_NONE)
info->debug(arg, write_only);
diff --git a/include/media/v4l2-dev.h b/include/media/v4l2-dev.h
index eb76cfd..3e4fddf 100644
--- a/include/media/v4l2-dev.h
+++ b/include/media/v4l2-dev.h
@@ -124,7 +124,8 @@
spinlock_t fh_lock; /* Lock for all v4l2_fhs */
struct list_head fh_list; /* List of struct v4l2_fh */
- int debug; /* Activates debug level*/
+ /* Internal device debug flags, not for use by drivers */
+ int dev_debug;
/* Video standard vars */
v4l2_std_id tvnorms; /* Supported tv norms */
diff --git a/include/media/v4l2-ioctl.h b/include/media/v4l2-ioctl.h
index 53605f0..8537983 100644
--- a/include/media/v4l2-ioctl.h
+++ b/include/media/v4l2-ioctl.h
@@ -291,9 +291,18 @@
/* v4l debugging and diagnostics */
-/* Debug bitmask flags to be used on V4L2 */
-#define V4L2_DEBUG_IOCTL 0x01
-#define V4L2_DEBUG_IOCTL_ARG 0x02
+/* Device debug flags to be used with the video device debug attribute */
+
+/* Just log the ioctl name + error code */
+#define V4L2_DEV_DEBUG_IOCTL 0x01
+/* Log the ioctl name arguments + error code */
+#define V4L2_DEV_DEBUG_IOCTL_ARG 0x02
+/* Log the file operations open, release, mmap and get_unmapped_area */
+#define V4L2_DEV_DEBUG_FOP 0x04
+/* Log the read and write file operations and the VIDIOC_(D)QBUF ioctls */
+#define V4L2_DEV_DEBUG_STREAMING 0x08
+/* Log poll() */
+#define V4L2_DEV_DEBUG_POLL 0x10
/* Video standard functions */
extern const char *v4l2_norm_to_name(v4l2_std_id id);