Hi Felipe, On Friday 23 Sep 2016 10:49:57 Felipe Balbi wrote: > Bin Liu <b-liu@xxxxxx> writes: > > +Fengwei Yin per his request. > > > > On Thu, Sep 22, 2016 at 10:48:40PM +0300, Felipe Balbi wrote: > >> Bin Liu <b-liu@xxxxxx> writes: > >> > >> [...] > >> > >>>> Here's one that actually compiles, sorry about that. > >>> > >>> No worries, I was sleeping ;-) > >>> > >>> I will test it out early next week. Thanks. > >> > >> meanwhile, how about some instructions on how to test this out myself? > >> How are you using g_webcam and what are you running on host side? Got a > >> nice list of commands there I can use? I think I can get to bottom of > >> this much quicker if I can reproduce it locally ;-) > > > > On device side: > > - first patch g_webcam as in my first email in this thread to enable > > > > 640x480@30fps; > > > > - # modprobe g_webcam streaming_maxpacket=3072 > > - then run uvc-gadget to feed the YUV frames; > > > > http://git.ideasonboard.org/uvc-gadget.git > > as is, g_webcam never enumerates to the host. It's calls to > usb_function_active() and usb_function_deactivate() are unbalanced. Do > you have any other changes to g_webcam? > > Also, uvc-gadget.git doesn't compile, had to modify it a bit: > > -#include "../drivers/usb/gadget/uvc.h" > +#include "../drivers/usb/gadget/function/uvc.h" > > Also fixed a build warning: > > @@ -732,6 +732,8 @@ int main(int argc, char *argv[]) > fd_set wfds = fds; > > ret = select(dev->fd + 1, NULL, &wfds, &efds, NULL); > + if (ret < 0) > + return ret; > if (FD_ISSET(dev->fd, &efds)) > uvc_events_process(dev); > if (FD_ISSET(dev->fd, &wfds)) > > Laurent, have you tested g_webcam recently? What's the magic to get it > working? I'm afraid not, I haven't had time to work on UVC gadget for a few years now. > Here's what I get out of dmesg: > > [ 58.568380] usb 1-9: new high-speed USB device number 5 using xhci_hcd > [ 58.738680] usb 1-9: New USB device found, idVendor=1d6b, idProduct=0102 > [ 58.738683] usb 1-9: New USB device strings: Mfr=1, Product=2, > SerialNumber=0 [ 58.738685] usb 1-9: Product: Webcam gadget > [ 58.738687] usb 1-9: Manufacturer: Linux Foundation > [ 58.739133] g_webcam gadget: high-speed config #1: Video > [ 58.739138] g_webcam gadget: uvc_function_set_alt(0, 0) > [ 58.739139] g_webcam gadget: reset UVC Control > [ 58.739149] g_webcam gadget: uvc_function_set_alt(1, 0) > [ 58.804369] uvcvideo: Found UVC 1.00 device Webcam gadget (1d6b:0102) > [ 58.804479] g_webcam gadget: uvc_function_set_alt(1, 0) > [ 64.188459] uvcvideo: UVC non compliance - GET_DEF(PROBE) not supported. > Enabling workaround. [ 69.307458] uvcvideo: Failed to query (129) UVC > probe control : -110 (exp. 26). [ 69.307459] uvcvideo: Failed to > initialize the device (-5). > [ 69.307505] usbcore: registered new interface driver uvcvideo > [ 69.307506] USB Video Class driver (1.1.1) > [ 146.646012] ------------[ cut here ]------------ > [ 146.646023] WARNING: CPU: 0 PID: 2616 at > drivers/usb/gadget/composite.c:371 usb_function_activate+0x77/0x80 > [libcomposite] [ 146.646024] Modules linked in: uvcvideo g_webcam > usb_f_uvc videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_core > videodev libcomposite kvm_intel kvm psmouse e1000e input_leds hid_generic > usbhid atkbd irqbypass evdev [ 146.646054] CPU: 0 PID: 2616 Comm: > gst-launch-1.0 Not tainted > 4.8.0-rc7-next-20160922-00004-gc71031593917-dirty #20 [ 146.646055] > Hardware name: Intel Corporation Skylake Client platform/Skylake Y LPDDR3 > RVP3, BIOS SKLSE2R1.R00.B097.B02.1509020030 09/02/2015 [ 146.646058] > ffffc9000769bb70 > [ 146.646059] ffffffff8132d415 > [ 146.646060] 0000000000000000 > [ 146.646061] 0000000000000000 > > [ 146.646063] ffffc9000769bbb0 > [ 146.646063] ffffffff8105ec1b > [ 146.646064] 000001730769bb90 > [ 146.646066] 00000000ffffffea > [ 146.646070] ffff88016c03a150 > [ 146.646072] 0000000000000282 ffff88016d793000 ffffc9000769befc > [ 146.646077] Call Trace: > [ 146.646086] [<ffffffff8132d415>] dump_stack+0x68/0x93 > [ 146.646090] [<ffffffff8105ec1b>] __warn+0xcb/0xf0 > [ 146.646095] [<ffffffff8105ed0d>] warn_slowpath_null+0x1d/0x20 > [ 146.646099] [<ffffffffa03f1ea7>] usb_function_activate+0x77/0x80 > [libcomposite] [ 146.646105] [<ffffffffa044a6de>] > uvc_function_connect+0x1e/0x40 [usb_f_uvc] [ 146.646110] > [<ffffffffa044b2ae>] uvc_v4l2_open+0x6e/0x80 [usb_f_uvc] [ 146.646116] > [<ffffffffa04014f0>] v4l2_open+0xa0/0x100 [videodev] [ 146.646121] > [<ffffffff811a5431>] chrdev_open+0xa1/0x1d0 > [ 146.646125] [<ffffffff811a5390>] ? cdev_put+0x30/0x30 > [ 146.646129] [<ffffffff8119dd60>] do_dentry_open.isra.17+0x150/0x2e0 > [ 146.646133] [<ffffffff8119f115>] vfs_open+0x45/0x60 > [ 146.646137] [<ffffffff811af1ed>] path_openat+0x62d/0x1370 > [ 146.646141] [<ffffffff811b0094>] ? putname+0x54/0x60 > [ 146.646146] [<ffffffff811b10ce>] do_filp_open+0x7e/0xe0 > [ 146.646150] [<ffffffff81083868>] ? preempt_count_sub+0x48/0x70 > [ 146.646154] [<ffffffff816f07d6>] ? _raw_spin_unlock+0x16/0x30 > [ 146.646160] [<ffffffff811bf009>] ? __alloc_fd+0xc9/0x180 > [ 146.646164] [<ffffffff8119f4e3>] do_sys_open+0x123/0x200 > [ 146.646170] [<ffffffff8119f5de>] SyS_open+0x1e/0x20 > [ 146.646174] [<ffffffff816f0e2a>] entry_SYSCALL_64_fastpath+0x18/0xa8 > [ 146.646177] ---[ end trace 1a4f7b9817d19b04 ]--- > [ 146.646180] g_webcam gadget: UVC connect failed with -22 > [ 146.653808] usb 1-9: USB disconnect, device number 5 > [ 146.653986] g_webcam gadget: UVC disconnect failed with -110 [snip] > uvc-gadget keeps printing this error message: > > 159 if ((ret = ioctl(dev->fd, VIDIOC_DQBUF, &buf)) < 0) { > 160 printf("Unable to dequeue buffer: %s (%d).\n", > strerror(errno), 161 errno); > 162 return ret; > 163 } > > Any ideas? The UVC gadget driver uses videobuf2 for buffer management. You can raise the debug level of the videobuf2-v4l2 and videobuf2-core modules to get verbose error messages in the kernel log. -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
