Hi Hans, Thanks for the patch. On Thursday 10 May 2012 09:05:11 Hans Verkuil wrote: > From: Hans Verkuil <hans.verkuil@xxxxxxxxx> > > Rather than testing whether an ioctl is implemented in the driver or not > every time the ioctl is called, do it upfront when the device is registered. > > This also allows a driver to disable certain ioctls based on the > capabilities of the detected board, something you can't do today without > creating separate v4l2_ioctl_ops structs for each new variation. > > For the most part it is pretty straightforward, but for control ioctls a > flag is needed since it is possible that you have per-filehandle controls, > and that can't be determined upfront of course. > > Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx> > --- > drivers/media/video/v4l2-dev.c | 171 +++++++++++++++++ > drivers/media/video/v4l2-ioctl.c | 391 ++++++++++------------------------- > include/media/v4l2-dev.h | 11 ++ > 3 files changed, 297 insertions(+), 276 deletions(-) > > diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c > index a51a061..4d98ee1 100644 > --- a/drivers/media/video/v4l2-dev.c > +++ b/drivers/media/video/v4l2-dev.c > @@ -516,6 +516,175 @@ static int get_index(struct video_device *vdev) > return find_first_zero_bit(used, VIDEO_NUM_DEVICES); > } > > +#define SET_VALID_IOCTL(ops, cmd, op) \ > + if (ops->op) \ > + set_bit(_IOC_NR(cmd), valid_ioctls) > + > +/* This determines which ioctls are actually implemented in the driver. > + It's a one-time thing which simplifies video_ioctl2 as it can just do > + a bit test. > + > + Note that drivers can override this by setting bits to 1 in > + vdev->valid_ioctls. If an ioctl is marked as 1 when this function is > + called, then that ioctl will actually be marked as unimplemented. > + > + It does that by first setting up the local valid_ioctls bitmap, and > + at the end do a: > + > + vdev->valid_ioctls = valid_ioctls & ~(vdev->valid_ioctls) Wouldn't it be more logical to initialize valid_ioctls to all 1s and clear bits in v4l2_dont_use_cmd() ? Otherwise the meaning of the field changes depending on whether the device is registered or not. Another bikeshedding comment, what about renaming v4l2_dont_use_cmd() with something that includes ioctl in the name ? - v4l2_dont_use_ioctl - v4l2_dont_use_ioctl_cmd - v4l2_ioctl_cmd_not_used - v4l2_ioctl_dont_use - v4l2_ioctl_dont_use_cmd - v4l2_disable_ioctl - v4l2_disable_ioctl_cmd ... (I like "disable" slightly better than "don't use"). > + */ -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
