search

3drobotics / solodevguide

Solo Development Guide (SDG).
http://dev.3dr.com/
41 stars 62 forks source link

VIDIOC_DQBUF error 62, Timer expired #302

Closed alexblack closed 8 years ago

alexblack commented 8 years ago

Sometimes when using SoloCamera from Python the camera component seems to crash with this error.

VIDIOC_DQBUF error 62, Timer expired
Exception in thread Thread-1:
Traceback (most recent call last):
  File "/usr/lib/python2.7/threading.py", line 551, in __bootstrap_inner
    self.run()
  File "/usr/lib/python2.7/threading.py", line 504, in run
    self.__target(*self.__args, **self.__kwargs)
  File "/opt/ddc/stream_solo.py", line 41, in read_video_thread
    result, buf = camera.read()
  File "/opt/ddc/SoloCamera.py", line 65, in read
    check(solocam.solocam_read_frame(self.ctx, byref(bufp)))
  File "/opt/ddc/SoloCamera.py", line 13, in check
    raise OSError("Error in solocam C call (see stderr)")
OSError: Error in solocam C call (see stderr)
alexblack commented 8 years ago

I'm still experiencing this often, I can reproduce it by pointing the drone (and the GoPro) at the window (a source of bright light). I am wondering if the GoPro is damaged?

alexblack commented 8 years ago

This is happening on my brand new (second) Solo with another brand new (second) GoPro 4 Silver

root@3dr_solo:~/ddc/examples/opencv# python SoloCamera.py
Capturing 10 images...
12.7108595118
21.2067023288
19.7777358633
56.5064464413
33.2158955921
36.2951514784
62.803084525
42.1957927989
45.057408044
37.115435327
38.3598467181
28.8849986571
27.119338424
55.1149656378
1.73423547838
VIDIOC_DQBUF error 62, Timer expired
Traceback (most recent call last):
  File "SoloCamera.py", line 86, in <module>
    ret, frame = cam.read()
  File "SoloCamera.py", line 65, in read
    check(solocam.solocam_read_frame(self.ctx, byref(bufp)))
  File "SoloCamera.py", line 13, in check
    raise OSError("Error in solocam C call (see stderr)")
OSError: Error in solocam C call (see stderr)
Exception AttributeError: "'NoneType' object has no attribute 'solocam_close'" in <bound method SoloCamera.__del__ of <__main__.SoloCamera object at 0x246b1b0>> ignored
root@3dr_solo:~/ddc/examples/opencv#
alexblack commented 8 years ago

I ran root@3dr_solo:/var/log# tail -f kern.log while reproducing the problem, and I see this output that looks related:

Apr  9 01:10:21 3dr_solo user.debug kernel: imx-ipuv3 2400000.ipu: CSI stop timeout - -44 * 10ms
Apr  9 01:10:26 3dr_solo user.debug kernel: imx-ipuv3 2400000.ipu: CSI_SENS_CONF = 0x00000950
Apr  9 01:10:26 3dr_solo user.debug kernel: imx-ipuv3 2400000.ipu: CSI_ACT_FRM_SIZE = 0x02CF04FF
Apr  9 01:10:26 3dr_solo user.warn kernel: alloc_contig_range test_pages_isolated(1cd00, 1ce52) failed
Apr  9 01:11:28 3dr_solo user.debug kernel: imx-ipuv3 2400000.ipu: CSI stop timeout - -44 * 10ms
Apr  9 01:11:28 3dr_solo user.debug kernel: imx-ipuv3 2400000.ipu: CSI_SENS_CONF = 0x00000950
Apr  9 01:11:28 3dr_solo user.debug kernel: imx-ipuv3 2400000.ipu: CSI_ACT_FRM_SIZE = 0x02CF04FF
Apr  9 01:11:38 3dr_solo user.err kernel: ERROR: v4l2 capture: mxc_v4l_dqueue timeout enc_counter 0
alexblack commented 8 years ago

Solved this! The fix was to modify a line in /etc/inittab to stop vidlaunch from running on startup, then reboot the drone.

Our theory is that

  1. vidlaunch initializes the video system before us, giving us errors when we start it
  2. vidlaunch is reactivated when the drone is moving, causing random timeouts in our video feed

Confirm the fix by running lsmod, expect mxc_v4l2_capture 22362 1 (Used by: 1, before the fix it is 3)

root@3dr_solo:~/ddc# lsmod
Module                  Size  Used by
mxc_v4l2_capture       22362  1
ipu_bg_overlay_sdc      3749  1 mxc_v4l2_capture
ipu_still               1663  1 mxc_v4l2_capture
ipu_prp_enc             4397  1 mxc_v4l2_capture
ipu_csi_enc             2593  1 mxc_v4l2_capture
ipu_fg_overlay_sdc      4625  1 mxc_v4l2_capture
cdc_acm                14295  0
ath9k                  94754  0
ath9k_common           19864  1 ath9k
ath9k_hw              363749  2 ath9k_common,ath9k
ath                    17786  3 ath9k_common,ath9k,ath9k_hw
mac80211              358702  1 ath9k
cfg80211              209856  4 ath,ath9k_common,ath9k,mac80211
adv7610_video           5327  0
compat                 16232  5 cfg80211,ath9k_common,ath9k,mac80211,ath9k_hw
usb_f_acm               4037  1
u_serial                7979  3 usb_f_acm
g_acm_ms               18540  0
libcomposite           26342  2 usb_f_acm,g_acm_ms