Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media into next

Pull media updates from Mauro Carvalho Chehab:
 "This contains:
   - a new frontend/tuner driver set for si2168 and sa2157
   - Videobuf 2 core now supports DVB too
   - A new gspca sub-driver (dtcs033)
   - saa7134 is now converted to use videobuf2
   - add support for 4K timings
   - several other driver fixes and improvements

  PS.  This pull request is shorter than usual, partly because I have
  some other patches on topic branches that I'll be sending you later
  this week"

* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (286 commits)
  [media] au0828-dvb: restore its permission to 644
  [media] xc5000: delay tuner sleep to 5 seconds
  [media] xc5000: Don't use whitespace before tabs
  [media] xc5000: fix CamelCase
  [media] xc5000: Don't wrap msleep()
  [media] xc5000: get rid of positive error codes
  [media] au0828: reset streaming when a new frequency is set
  [media] au0828: Improve debug messages for urb_completion
  [media] au0828: Cancel stream-restart operation if frontend is disconnected
  [media] dib0700: fix RC support on Hauppauge Nova-TD
  [media] USB: as102_usb_drv.c: Remove useless return variables
  [media] v4l: Fix documentation of V4L2_PIX_FMT_H264_MVC and VP8 pixel formats
  [media] m5mols: Replace missing header
  [media] staging: lirc: Fix sparse warnings
  [media] fix mceusb endpoint type identification/handling
  [media] az6027: Added the PID for a new revision of the Elgato EyeTV Sat DVB-S Tuner
  [media] DocBook media: fix typo
  [media] adv7604: Add missing include to linux/types.h
  [media] v4l: Validate fields in the core code for subdev EDID ioctls
  [media] v4l: Add support for DV timings ioctls on subdev nodes
  ...

1 files changed, 15 insertions, 3 deletions

diff --git a/drivers/media/v4l2-core/v4l2-device.c b/drivers/media/v4l2-core/v4l2-device.c
index 02d1b632711..015f92aab44 100644
--- a/drivers/media/v4l2-core/v4l2-device.c
+++ b/drivers/media/v4l2-core/v4l2-device.c
@@ -158,7 +158,17 @@ int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
 	/* Warn if we apparently re-register a subdev */
 	WARN_ON(sd->v4l2_dev != NULL);
 
-	if (!try_module_get(sd->owner))
+	/*
+	 * The reason to acquire the module here is to avoid unloading
+	 * a module of sub-device which is registered to a media
+	 * device. To make it possible to unload modules for media
+	 * devices that also register sub-devices, do not
+	 * try_module_get() such sub-device owners.
+	 */
+	sd->owner_v4l2_dev = v4l2_dev->dev && v4l2_dev->dev->driver &&
+		sd->owner == v4l2_dev->dev->driver->owner;
+
+	if (!sd->owner_v4l2_dev && !try_module_get(sd->owner))
 		return -ENODEV;
 
 	sd->v4l2_dev = v4l2_dev;
@@ -192,7 +202,8 @@ error_unregister:
 	if (sd->internal_ops && sd->internal_ops->unregistered)
 		sd->internal_ops->unregistered(sd);
 error_module:
-	module_put(sd->owner);
+	if (!sd->owner_v4l2_dev)
+		module_put(sd->owner);
 	sd->v4l2_dev = NULL;
 	return err;
 }
@@ -280,6 +291,7 @@ void v4l2_device_unregister_subdev(struct v4l2_subdev *sd)
 	}
 #endif
 	video_unregister_device(sd->devnode);
-	module_put(sd->owner);
+	if (!sd->owner_v4l2_dev)
+		module_put(sd->owner);
 }
 EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev);