That is strange because there are several developers who have managed to get logitech cameras working:
https://www.google.com/search?q=beaglebone+logitech+c920&oq=bea&aqs=chrome.0.69i59l3j0l2j69i65.2901j0j4&sourceid=chrome&es_sm=119&ie=UTF-8 <https://www.google.com/search?q=beaglebone+logitech+c920&oq=bea&aqs=chrome.0.69i59l3j0l2j69i65.2901j0j4&sourceid=chrome&es_sm=119&ie=UTF-8> I recommend you start with Robert’s latest Debian. I’ve had issues with Ubuntu in the past. Regards, John > On Feb 15, 2016, at 2:00 PM, joelk <[email protected]> wrote: > > > Thanks John, I have seen Derek's videos and other resources, and I've ordered > a C920 but haven't received it yet. We'll see, but frankly I doubt that it > will solve these issues completely. I find it hard to believe that cpu load > is the main issue here. For example, I just booted up with the webcam > unplugged. I plugged it in, checked dmesg to see that the webcam and > uvcvideo were registered and seemed to be working, and they were. I ran > v4l2-ctl --all to verify that I could connect to the camera. Then I > immediately rebooted (sudo reboot), leaving the camera plugged in to the usb > jack. Guess what? No good! When I try to run > v4l2-ctl --all I get: > Failed to open /dev/video0: Permission denied > > I hesitate to post the entire output from dmesg, but here's the last section > -- this entire group of lines was repeated 4 times: > > [ 601.019165] INFO: task v4l_id:551 blocked for more than 120 seconds. > [ 601.025624] Not tainted 4.1.15-ti-rt-r40 #1 > [ 601.031932] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables > this message. > [ 601.040887] v4l_id D c09d0558 0 551 1 0x00000001 > [ 601.041028] [<c09d0558>] (__schedule) from [<c09d08ac>] (schedule+0x58/0xe4) > [ 601.041089] [<c09d08ac>] (schedule) from [<c09d1c88>] > (__rt_mutex_slowlock+0xf4/0x188) > [ 601.041142] [<c09d1c88>] (__rt_mutex_slowlock) from [<c09d2284>] > (rt_mutex_slowlock+0x13c/0x338) > [ 601.041192] [<c09d2284>] (rt_mutex_slowlock) from [<c09d24f4>] > (rt_mutex_lock+0x74/0x78) > [ 601.041245] [<c09d24f4>] (rt_mutex_lock) from [<c0094e4c>] > (__rt_down_read+0x3c/0x4c) > [ 601.041298] [<c0094e4c>] (__rt_down_read) from [<c0094e78>] > (rt_down_read+0x1c/0x20) > [ 601.041515] [<c0094e78>] (rt_down_read) from [<bf0f0064>] > (snd_usb_autoresume+0x24/0x60 [snd_usb_audio]) > [ 601.041710] [<bf0f0064>] (snd_usb_autoresume [snd_usb_audio]) from > [<bf0f43d4>] (snd_usb_mixer_set_ctl_value+0xb8/0x24c [snd_usb_audio]) > [ 601.041895] [<bf0f43d4>] (snd_usb_mixer_set_ctl_value [snd_usb_audio]) from > [<bf0f4764>] (snd_usb_set_cur_mix_value+0x7c/0xe4 [snd_usb_audio]) > [ 601.042073] [<bf0f4764>] (snd_usb_set_cur_mix_value [snd_usb_audio]) from > [<bf0f51c0>] (restore_mixer_value+0xa8/0xb0 [snd_usb_audio]) > [ 601.042255] [<bf0f51c0>] (restore_mixer_value [snd_usb_audio]) from > [<bf0f7104>] (snd_usb_mixer_resume+0x48/0x8c [snd_usb_audio]) > [ 601.042426] [<bf0f7104>] (snd_usb_mixer_resume [snd_usb_audio]) from > [<bf0ef078>] (__usb_audio_resume+0x78/0x104 [snd_usb_audio]) > [ 601.042579] [<bf0ef078>] (__usb_audio_resume [snd_usb_audio]) from > [<bf0ef120>] (usb_audio_reset_resume+0x1c/0x20 [snd_usb_audio]) > [ 601.042705] [<bf0ef120>] (usb_audio_reset_resume [snd_usb_audio]) from > [<c072c4f0>] (usb_resume_interface+0xa0/0x158) > [ 601.042768] [<c072c4f0>] (usb_resume_interface) from [<c072c7d0>] > (usb_resume_both+0x80/0x14c) > [ 601.042822] [<c072c7d0>] (usb_resume_both) from [<c072d78c>] > (usb_runtime_resume+0x20/0x24) > [ 601.042889] [<c072d78c>] (usb_runtime_resume) from [<c066d744>] > (__rpm_callback+0x34/0x4c) > [ 601.042945] [<c066d744>] (__rpm_callback) from [<c066d78c>] > (rpm_callback+0x30/0x90) > [ 601.042999] [<c066d78c>] (rpm_callback) from [<c066eb00>] > (rpm_resume+0x438/0x6d8) > [ 601.043053] [<c066eb00>] (rpm_resume) from [<c066e96c>] > (rpm_resume+0x2a4/0x6d8) > [ 601.043107] [<c066e96c>] (rpm_resume) from [<c066edfc>] > (__pm_runtime_resume+0x5c/0x74) > [ 601.043163] [<c066edfc>] (__pm_runtime_resume) from [<c072c2b4>] > (usb_autopm_get_interface+0x28/0x6c) > [ 601.043291] [<c072c2b4>] (usb_autopm_get_interface) from [<bf14a5dc>] > (uvc_v4l2_open+0x50/0x140 [uvcvideo]) > [ 601.043558] [<bf14a5dc>] (uvc_v4l2_open [uvcvideo]) from [<bf0ab5ec>] > (v4l2_open+0xb4/0xf0 [videodev]) > [ 601.043706] [<bf0ab5ec>] (v4l2_open [videodev]) from [<c01b4048>] > (chrdev_open+0xbc/0x1a8) > [ 601.043765] [<c01b4048>] (chrdev_open) from [<c01adc58>] > (do_dentry_open+0x1e4/0x310) > [ 601.043817] [<c01adc58>] (do_dentry_open) from [<c01ae960>] > (vfs_open+0x70/0x78) > [ 601.043871] [<c01ae960>] (vfs_open) from [<c01bbe60>] (do_last+0x3c8/0xf08) > [ 601.043923] [<c01bbe60>] (do_last) from [<c01be618>] > (path_openat+0x90/0x618) > [ 601.043975] [<c01be618>] (path_openat) from [<c01bfc08>] > (do_filp_open+0x3c/0x90) > [ 601.044026] [<c01bfc08>] (do_filp_open) from [<c01aecbc>] > (do_sys_open+0x11c/0x1e0) > [ 601.044075] [<c01aecbc>] (do_sys_open) from [<c01aedac>] > (SyS_open+0x2c/0x30) > [ 601.044135] [<c01aedac>] (SyS_open) from [<c0010720>] > (ret_fast_syscall+0x0/0x3c) > > This all occurred before any attempt was made to capture any video or even > turn the camera on, so it's hard to see why hardware encoding would make any > difference. Maybe Derek was just lucky. > > And if talking about luck sounds silly consider this: a couple of days ago, > during one of the occasions that the webcam managed to get itself registered > successfully, I compiled a simple little program (similar to but simpler than > Derek's "boneCV", using cv::VideoCapture to grab and save a single image. > Time after time it saved a completely black image. And then (I can't explain > why I tried it so many times - just stubbornness I guess) it worked. Seems > to work about 10-15% of the time, saving a perfectly good image. Then it > goes back to black. I don't think that's cpu load. > > -- > For more options, visit http://beagleboard.org/discuss > <http://beagleboard.org/discuss> > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] > <mailto:[email protected]>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
