On Sat, Apr 20, 2019 at 5:44 PM Zebediah Figura z.figura12@gmail.com wrote:
On 4/20/19 10:31 AM, Damjan Jovanovic wrote:
On Sat, Apr 20, 2019 at 4:52 PM Zebediah Figura <z.figura12@gmail.com mailto:z.figura12@gmail.com> wrote:
On 4/20/19 8:15 AM, Damjan Jovanovic wrote: > Recent changes to qcap/v4l.c resulted in the removal of mmap() > for v4l2 devices, but read() is optional for device drivers and > some don't support it. This isn't a major problem with the > presense of libv4l2 though, as it can emulate read() on top of > mmap(). However the code checks whether the device can read(), > and if not, doesn't even try to use it, even though it can. > > Fix this by only warning that read() is being emulated, and > continuing with libv4l2 if available. > > Also clarifies the logging. > > Signed-off-by: Damjan Jovanovic <damjan.jov@gmail.com <mailto:damjan.jov@gmail.com>> > --- > dlls/qcap/v4l.c | 13 ++++++++----- > 1 file changed, 8 insertions(+), 5 deletions(-) > > > This doesn't seem right; libv4l2 should massage the result of VIDIOC_QUERYCAP to include V4L2_CAP_READWRITE. See <https://git.linuxtv.org/v4l-utils.git/tree/lib/libv4l2/libv4l2.c#n1210%3E.
On FreeBSD 11.2 with libv4l-1.6.3_4, that is certainly NOT the case. It could be a newer or not yet released feature.
It's been the case since libv4l2 0.5: < https://git.linuxtv.org/v4l-utils.git/commit/lib/libv4l2/libv4l2.c?id=0215f2...
If FreeBSD is using 1.6.3, then I think something else is wrong. Are you sure that libv4l2 is actually being loaded?
$ grep v4l /proc/74345/map 0x64ed6000 0x64ede000 8 11 0xfffff80239c004b0 r-x 2 1 0x1000 COW NC vnode /compat/freebsd-i386/usr/local/lib/libv4l2.so.0.0.0 NCH -1 0x64ede000 0x64ee2000 4 0 0xfffff80260dcdd20 rw- 1 0 0x3000 COW NNC vnode /compat/freebsd-i386/usr/local/lib/libv4l2.so.0.0.0 CH 1002 0x64ee2000 0x64f01000 31 33 0xfffff803549822d0 r-x 2 1 0x1000 COW NC vnode /compat/freebsd-i386/usr/local/lib/libv4lconvert.so.0.0.0 NCH -1 0x64f01000 0x64f03000 2 0 0xfffff8038cc0c1e0 rw- 1 0 0x3000 COW NNC vnode /compat/freebsd-i386/usr/local/lib/libv4lconvert.so.0.0.0 CH 1002
caps.capabilities are 0x84a00001 0x000000001 = V4L2_CAP_VIDEO_CAPTURE 0x00200000 = V4L2_CAP_EXT_PIX_FORMAT 0x00800000 = V4L2_CAP_META_CAPTURE 0x040000000 = V4L2_CAP_STREAMING 0x800000000 = V4L2_CAP_DEVICE_CAPS