PureThermal2 UVC video camera: Failed to submit URB 0 (-28)

PureThermal2 UVC video camera: Failed to submit URB 0 (-28)

[Tim Harvey]

Greetings,

I'm running into an issue with a USB UVC Full speed camera, the
PureThermal2 [1] on an IMX6 based ARM board.

What I find is that I get two video devices registered (the first one
is the expected device, and I'm not clear what the 2nd one is). When I
try to capture a single frame I get 'Failed to submit URB 0 (-28)'
which historically has been due to a bandwidth issue. I encounter this
on the IMX6 EHCI host as well as the OTG host when no other devices
are connected (no hubs either). I've tested with both a 4.20 kernel
and a 5.3 kernel.

If I plug this device into another board I have based on an OcteonTX
ARM64 cpu with a fairly modern 4.14 kernel and I find that a single
video device gets registered and I can capture just fine.

Here are some details:
lsusb reports: 1e4e:0100 Cubeternet WebCam

working system with 4.14 kernel hot-inserting the camera:
[  495.163276] usb 1-1.2: new full-speed USB device number 6 using xhci_hcd
[  495.291685] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
(1e4e:0100)
[  495.300543] input: PureThermal (fw:v1.2.2): PureTh as
/devices/platform/soc@0/848000000000.pci/pci0000:00/0000:00:10.0/usb1/1-1/1-1.2/1-1.2:1.0/input/input1
[  496.731214] usb 1-1.2: USB disconnect, device number 6
[  496.987294] usb 1-1.2: new full-speed USB device number 7 using xhci_hcd
[  497.115683] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
(1e4e:0100)
[  497.124182] input: PureThermal (fw:v1.2.2): PureTh as
/devices/platform/soc@0/848000000000.pci/pci0000:00/0000:00:10.0/usb1/1-1/1-1.2/1-1.2:1.0/input/input2
root@bionic-newport:~# for i in $(ls -1d
/sys/class/video4linux/video*); do echo $i:$(cat $i/name); done
/sys/class/video4linux/video0:PureThermal (fw:v1.2.2): PureTh
root@bionic-newport:~# v4l2-ctl --device=/dev/video0 --allDriver Info
(not using libv4l2):
Driver name   : uvcvideo
Card type     : PureThermal (fw:v1.2.2): PureTh
Bus info      : usb-0000:00:10.0-1.2
Driver version: 4.14.4
Capabilities  : 0x84200001
Video Capture
Streaming
Extended Pix Format
Device Capabilities
Device Caps   : 0x04200001
Video Capture
Streaming
Extended Pix Format
Priority: 2
Video input : 0 (Camera 1: ok)
Format Video Capture:
Width/Height      : 160/120
Pixel Format      : 'UYVY'
Field             : None
Bytes per Line    : 320
Size Image        : 38400
Colorspace        : sRGB
Transfer Function : Default (maps to sRGB)
YCbCr/HSV Encoding: Default (maps to ITU-R 601)
Quantization      : Default (maps to Limited Range)
Flags             :
Crop Capability Video Capture:
Bounds      : Left 0, Top 0, Width 160, Height 120
Default     : Left 0, Top 0, Width 160, Height 120
Pixel Aspect: 1/1
Selection: crop_default, Left 0, Top 0, Width 160, Height 120
Selection: crop_bounds, Left 0, Top 0, Width 160, Height 120
Streaming Parameters Video Capture:
Capabilities     : timeperframe
Frames per second: 9.000 (9/1)
Read buffers     : 0
                     brightness 0x00980900 (int)    : min=0 max=255
step=1 default=128 value=128
                       contrast 0x00980901 (int)    : min=0 max=255
step=1 default=128 value=128
root@bionic-newport:~# v4l2-ctl --device=/dev/video0 --stream-mmap
--stream-to=x.raw --stream-count=1
<
root@bionic-newport:~# ls -l x.raw
-rw-r--r-- 1 root root 38400 Sep 26 22:25 x.raw

non-working system with 5.3 kernel hot-inserting the device
[   54.252434] usb 2-1: new full-speed USB device number 2 using ci_hdrc
[   54.463017] usb 2-1: New USB device found, idVendor=1e4e,
idProduct=0100, bcdDevice= 2.00
[   54.463097] usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[   54.463114] usb 2-1: Product: PureThermal (fw:v1.2.2)
[   54.463130] usb 2-1: Manufacturer: GroupGets
[   54.463145] usb 2-1: SerialNumber: 801f001c-5102-3038-3835-393400000000
[   54.470265] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
(1e4e:0100)
[   54.480219] uvcvideo 2-1:1.0: Entity type for entity Extension 3
was not initialized!
[   54.480315] uvcvideo 2-1:1.0: Entity type for entity Processing 2
was not initialized!
[   54.480342] uvcvideo 2-1:1.0: Entity type for entity Extension 4
was not initialized!
[   54.480366] uvcvideo 2-1:1.0: Entity type for entity Extension 5
was not initialized!
[   54.480388] uvcvideo 2-1:1.0: Entity type for entity Extension 6
was not initialized!
[   54.480409] uvcvideo 2-1:1.0: Entity type for entity Extension 7
was not initialized!
[   54.480431] uvcvideo 2-1:1.0: Entity type for entity Extension 21
was not initialized!
[   54.480452] uvcvideo 2-1:1.0: Entity type for entity Extension 254
was not initialized!
[   54.480473] uvcvideo 2-1:1.0: Entity type for entity Camera 1 was
not initialized!
[   54.481802] input: PureThermal (fw:v1.2.2): PureTh as
/devices/soc0/soc/2100000.aips-bus/2184200.usb/ci_hdrc.1/usb2/2-1/2-1:1.0/input/input1
[   55.733320] usb 2-1: USB disconnect, device number 2
[   56.252329] usb 2-1: new full-speed USB device number 3 using ci_hdrc
[   56.462977] usb 2-1: New USB device found, idVendor=1e4e,
idProduct=0100, bcdDevice= 2.00
[   56.462998] usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[   56.463015] usb 2-1: Product: PureThermal (fw:v1.2.2)
[   56.463030] usb 2-1: Manufacturer: GroupGets
[   56.463044] usb 2-1: SerialNumber: 801f001c-5102-3038-3835-393400000000
[   56.466135] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
(1e4e:0100)
[   56.473750] uvcvideo 2-1:1.0: Entity type for entity Extension 3
was not initialized!
[   56.473784] uvcvideo 2-1:1.0: Entity type for entity Processing 2
was not initialized!
[   56.473807] uvcvideo 2-1:1.0: Entity type for entity Extension 4
was not initialized!
[   56.473829] uvcvideo 2-1:1.0: Entity type for entity Extension 5
was not initialized!
[   56.473851] uvcvideo 2-1:1.0: Entity type for entity Extension 6
was not initialized!
[   56.473875] uvcvideo 2-1:1.0: Entity type for entity Extension 7
was not initialized!
[   56.473898] uvcvideo 2-1:1.0: Entity type for entity Extension 21
was not initialized!
[   56.473919] uvcvideo 2-1:1.0: Entity type for entity Extension 254
was not initialized!
[   56.473941] uvcvideo 2-1:1.0: Entity type for entity Camera 1 was
not initialized!
[   56.475097] input: PureThermal (fw:v1.2.2): PureTh as
/devices/soc0/soc/2100000.aips-bus/2184200.usb/ci_hdrc.1/usb2/2-1/2-1:1.0/input/input2
root@bionic-armhf:~# for i in $(ls -1d /sys/class/video4linux/video*);
do echo $i:$(cat $i/name); done
/sys/class/video4linux/video0:ipu1_csi0 capture
/sys/class/video4linux/video1:ipu1_ic_prpenc capture
/sys/class/video4linux/video10:PureThermal (fw:v1.2.2): PureTh
/sys/class/video4linux/video2:ipu1_ic_prpvf capture
/sys/class/video4linux/video3:ipu1_csi1 capture
/sys/class/video4linux/video4:ipu2_csi0 capture
/sys/class/video4linux/video5:ipu2_ic_prpenc capture
/sys/class/video4linux/video6:ipu2_ic_prpvf capture
/sys/class/video4linux/video7:ipu2_csi1 capture
/sys/class/video4linux/video8:ipu_ic_pp csc/scaler
/sys/class/video4linux/video9:PureThermal (fw:v1.2.2): PureTh
^^^^ why 2 video devices for this camera when the working system only had 1?
root@bionic-armhf:~# v4l2-ctl --device=/dev/video9 --all
Driver Info (not using libv4l2):
Driver name   : uvcvideo
Card type     : PureThermal (fw:v1.2.2): PureTh
Bus info      : usb-ci_hdrc.1-1
Driver version: 5.3.0
Capabilities  : 0x84A00001
Video Capture
Metadata Capture
Streaming
Extended Pix Format
Device Capabilities
Device Caps   : 0x04200001
Video Capture
Streaming
Extended Pix Format
Priority: 2
Video input : 0 (Camera 1: ok)
Format Video Capture:
Width/Height      : 160/120
Pixel Format      : 'UYVY'
Field             : None
Bytes per Line    : 320
Size Image        : 38400
Colorspace        : sRGB
Transfer Function : Default (maps to sRGB)
YCbCr/HSV Encoding: Default (maps to ITU-R 601)
Quantization      : Default (maps to Limited Range)
Flags             :
Crop Capability Video Capture:
Bounds      : Left 0, Top 0, Width 160, Height 120
Default     : Left 0, Top 0, Width 160, Height 120
Pixel Aspect: 1/1
Selection: crop_default, Left 0, Top 0, Width 160, Height 120
Selection: crop_bounds, Left 0, Top 0, Width 160, Height 120
Streaming Parameters Video Capture:
Capabilities     : timeperframe
Frames per second: 9.000 (9/1)
Read buffers     : 0
                     brightness 0x00980900 (int)    : min=0 max=255
step=1 default=128 value=128
                       contrast 0x00980901 (int)    : min=0 max=255
step=1 default=128 value=128
root@bionic-armhf:~# v4l2-ctl --device=/dev/video9 --stream-mmap
--stream-to=x.raw --stream-count=1
[  134.601561] uvcvideo: Failed to submit URB 0 (-28).
VIDIOC_STREAMON: failed: No space left on device
^^^ the issue
root@bionic-armhf:~# v4l2-ctl --device=/dev/video10 --all
Driver Info (not using libv4l2):
Driver name   : uvcvideo
Card type     : PureThermal (fw:v1.2.2): PureTh
Bus info      : usb-ci_hdrc.1-1
Driver version: 5.3.0
Capabilities  : 0x84A00001
Video Capture
Metadata Capture
Streaming
Extended Pix Format
Device Capabilities
Device Caps   : 0x04A00000
Metadata Capture
Streaming
Extended Pix Format
Priority: 2
root@bionic-armhf:~# v4l2-ctl --device=/dev/video10 --stream-mmap
--stream-to=x.raw --stream-count=1
unsupported stream type
^^^ no idea what this 2nd video device is

I'm also not clear why the device enumerates then disconnects and
enumerates again when plugged in but this happens on the system it
works on as well and I've seen similar things with other devices.

Any ideas?

Best Regards,

Tim
[1] https://groupgets.com/manufacturers/getlab/products/purethermal-2-flir-lepton-smart-i-o-module

Re: PureThermal2 UVC video camera: Failed to submit URB 0 (-28)

[Tim Harvey]

On Thu, Sep 26, 2019 at 3:47 PM Tim Harvey <tharvey@gateworks.com> wrote:
>
> Greetings,
>
> I'm running into an issue with a USB UVC Full speed camera, the
> PureThermal2 [1] on an IMX6 based ARM board.
>
> What I find is that I get two video devices registered (the first one
> is the expected device, and I'm not clear what the 2nd one is). When I
> try to capture a single frame I get 'Failed to submit URB 0 (-28)'
> which historically has been due to a bandwidth issue. I encounter this
> on the IMX6 EHCI host as well as the OTG host when no other devices
> are connected (no hubs either). I've tested with both a 4.20 kernel
> and a 5.3 kernel.
>
> If I plug this device into another board I have based on an OcteonTX
> ARM64 cpu with a fairly modern 4.14 kernel and I find that a single
> video device gets registered and I can capture just fine.
>
> Here are some details:
> lsusb reports: 1e4e:0100 Cubeternet WebCam
>
> working system with 4.14 kernel hot-inserting the camera:
> [  495.163276] usb 1-1.2: new full-speed USB device number 6 using xhci_hcd
> [  495.291685] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
> (1e4e:0100)
> [  495.300543] input: PureThermal (fw:v1.2.2): PureTh as
> /devices/platform/soc@0/848000000000.pci/pci0000:00/0000:00:10.0/usb1/1-1/1-1.2/1-1.2:1.0/input/input1
> [  496.731214] usb 1-1.2: USB disconnect, device number 6
> [  496.987294] usb 1-1.2: new full-speed USB device number 7 using xhci_hcd
> [  497.115683] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
> (1e4e:0100)
> [  497.124182] input: PureThermal (fw:v1.2.2): PureTh as
> /devices/platform/soc@0/848000000000.pci/pci0000:00/0000:00:10.0/usb1/1-1/1-1.2/1-1.2:1.0/input/input2
> root@bionic-newport:~# for i in $(ls -1d
> /sys/class/video4linux/video*); do echo $i:$(cat $i/name); done
> /sys/class/video4linux/video0:PureThermal (fw:v1.2.2): PureTh
> root@bionic-newport:~# v4l2-ctl --device=/dev/video0 --allDriver Info
> (not using libv4l2):
> Driver name   : uvcvideo
> Card type     : PureThermal (fw:v1.2.2): PureTh
> Bus info      : usb-0000:00:10.0-1.2
> Driver version: 4.14.4
> Capabilities  : 0x84200001
> Video Capture
> Streaming
> Extended Pix Format
> Device Capabilities
> Device Caps   : 0x04200001
> Video Capture
> Streaming
> Extended Pix Format
> Priority: 2
> Video input : 0 (Camera 1: ok)
> Format Video Capture:
> Width/Height      : 160/120
> Pixel Format      : 'UYVY'
> Field             : None
> Bytes per Line    : 320
> Size Image        : 38400
> Colorspace        : sRGB
> Transfer Function : Default (maps to sRGB)
> YCbCr/HSV Encoding: Default (maps to ITU-R 601)
> Quantization      : Default (maps to Limited Range)
> Flags             :
> Crop Capability Video Capture:
> Bounds      : Left 0, Top 0, Width 160, Height 120
> Default     : Left 0, Top 0, Width 160, Height 120
> Pixel Aspect: 1/1
> Selection: crop_default, Left 0, Top 0, Width 160, Height 120
> Selection: crop_bounds, Left 0, Top 0, Width 160, Height 120
> Streaming Parameters Video Capture:
> Capabilities     : timeperframe
> Frames per second: 9.000 (9/1)
> Read buffers     : 0
>                      brightness 0x00980900 (int)    : min=0 max=255
> step=1 default=128 value=128
>                        contrast 0x00980901 (int)    : min=0 max=255
> step=1 default=128 value=128
> root@bionic-newport:~# v4l2-ctl --device=/dev/video0 --stream-mmap
> --stream-to=x.raw --stream-count=1
> <
> root@bionic-newport:~# ls -l x.raw
> -rw-r--r-- 1 root root 38400 Sep 26 22:25 x.raw
>
> non-working system with 5.3 kernel hot-inserting the device
> [   54.252434] usb 2-1: new full-speed USB device number 2 using ci_hdrc
> [   54.463017] usb 2-1: New USB device found, idVendor=1e4e,
> idProduct=0100, bcdDevice= 2.00
> [   54.463097] usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
> [   54.463114] usb 2-1: Product: PureThermal (fw:v1.2.2)
> [   54.463130] usb 2-1: Manufacturer: GroupGets
> [   54.463145] usb 2-1: SerialNumber: 801f001c-5102-3038-3835-393400000000
> [   54.470265] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
> (1e4e:0100)
> [   54.480219] uvcvideo 2-1:1.0: Entity type for entity Extension 3
> was not initialized!
> [   54.480315] uvcvideo 2-1:1.0: Entity type for entity Processing 2
> was not initialized!
> [   54.480342] uvcvideo 2-1:1.0: Entity type for entity Extension 4
> was not initialized!
> [   54.480366] uvcvideo 2-1:1.0: Entity type for entity Extension 5
> was not initialized!
> [   54.480388] uvcvideo 2-1:1.0: Entity type for entity Extension 6
> was not initialized!
> [   54.480409] uvcvideo 2-1:1.0: Entity type for entity Extension 7
> was not initialized!
> [   54.480431] uvcvideo 2-1:1.0: Entity type for entity Extension 21
> was not initialized!
> [   54.480452] uvcvideo 2-1:1.0: Entity type for entity Extension 254
> was not initialized!
> [   54.480473] uvcvideo 2-1:1.0: Entity type for entity Camera 1 was
> not initialized!
> [   54.481802] input: PureThermal (fw:v1.2.2): PureTh as
> /devices/soc0/soc/2100000.aips-bus/2184200.usb/ci_hdrc.1/usb2/2-1/2-1:1.0/input/input1
> [   55.733320] usb 2-1: USB disconnect, device number 2
> [   56.252329] usb 2-1: new full-speed USB device number 3 using ci_hdrc
> [   56.462977] usb 2-1: New USB device found, idVendor=1e4e,
> idProduct=0100, bcdDevice= 2.00
> [   56.462998] usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
> [   56.463015] usb 2-1: Product: PureThermal (fw:v1.2.2)
> [   56.463030] usb 2-1: Manufacturer: GroupGets
> [   56.463044] usb 2-1: SerialNumber: 801f001c-5102-3038-3835-393400000000
> [   56.466135] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
> (1e4e:0100)
> [   56.473750] uvcvideo 2-1:1.0: Entity type for entity Extension 3
> was not initialized!
> [   56.473784] uvcvideo 2-1:1.0: Entity type for entity Processing 2
> was not initialized!
> [   56.473807] uvcvideo 2-1:1.0: Entity type for entity Extension 4
> was not initialized!
> [   56.473829] uvcvideo 2-1:1.0: Entity type for entity Extension 5
> was not initialized!
> [   56.473851] uvcvideo 2-1:1.0: Entity type for entity Extension 6
> was not initialized!
> [   56.473875] uvcvideo 2-1:1.0: Entity type for entity Extension 7
> was not initialized!
> [   56.473898] uvcvideo 2-1:1.0: Entity type for entity Extension 21
> was not initialized!
> [   56.473919] uvcvideo 2-1:1.0: Entity type for entity Extension 254
> was not initialized!
> [   56.473941] uvcvideo 2-1:1.0: Entity type for entity Camera 1 was
> not initialized!
> [   56.475097] input: PureThermal (fw:v1.2.2): PureTh as
> /devices/soc0/soc/2100000.aips-bus/2184200.usb/ci_hdrc.1/usb2/2-1/2-1:1.0/input/input2
> root@bionic-armhf:~# for i in $(ls -1d /sys/class/video4linux/video*);
> do echo $i:$(cat $i/name); done
> /sys/class/video4linux/video0:ipu1_csi0 capture
> /sys/class/video4linux/video1:ipu1_ic_prpenc capture
> /sys/class/video4linux/video10:PureThermal (fw:v1.2.2): PureTh
> /sys/class/video4linux/video2:ipu1_ic_prpvf capture
> /sys/class/video4linux/video3:ipu1_csi1 capture
> /sys/class/video4linux/video4:ipu2_csi0 capture
> /sys/class/video4linux/video5:ipu2_ic_prpenc capture
> /sys/class/video4linux/video6:ipu2_ic_prpvf capture
> /sys/class/video4linux/video7:ipu2_csi1 capture
> /sys/class/video4linux/video8:ipu_ic_pp csc/scaler
> /sys/class/video4linux/video9:PureThermal (fw:v1.2.2): PureTh
> ^^^^ why 2 video devices for this camera when the working system only had 1?
> root@bionic-armhf:~# v4l2-ctl --device=/dev/video9 --all
> Driver Info (not using libv4l2):
> Driver name   : uvcvideo
> Card type     : PureThermal (fw:v1.2.2): PureTh
> Bus info      : usb-ci_hdrc.1-1
> Driver version: 5.3.0
> Capabilities  : 0x84A00001
> Video Capture
> Metadata Capture
> Streaming
> Extended Pix Format
> Device Capabilities
> Device Caps   : 0x04200001
> Video Capture
> Streaming
> Extended Pix Format
> Priority: 2
> Video input : 0 (Camera 1: ok)
> Format Video Capture:
> Width/Height      : 160/120
> Pixel Format      : 'UYVY'
> Field             : None
> Bytes per Line    : 320
> Size Image        : 38400
> Colorspace        : sRGB
> Transfer Function : Default (maps to sRGB)
> YCbCr/HSV Encoding: Default (maps to ITU-R 601)
> Quantization      : Default (maps to Limited Range)
> Flags             :
> Crop Capability Video Capture:
> Bounds      : Left 0, Top 0, Width 160, Height 120
> Default     : Left 0, Top 0, Width 160, Height 120
> Pixel Aspect: 1/1
> Selection: crop_default, Left 0, Top 0, Width 160, Height 120
> Selection: crop_bounds, Left 0, Top 0, Width 160, Height 120
> Streaming Parameters Video Capture:
> Capabilities     : timeperframe
> Frames per second: 9.000 (9/1)
> Read buffers     : 0
>                      brightness 0x00980900 (int)    : min=0 max=255
> step=1 default=128 value=128
>                        contrast 0x00980901 (int)    : min=0 max=255
> step=1 default=128 value=128
> root@bionic-armhf:~# v4l2-ctl --device=/dev/video9 --stream-mmap
> --stream-to=x.raw --stream-count=1
> [  134.601561] uvcvideo: Failed to submit URB 0 (-28).
> VIDIOC_STREAMON: failed: No space left on device
> ^^^ the issue
> root@bionic-armhf:~# v4l2-ctl --device=/dev/video10 --all
> Driver Info (not using libv4l2):
> Driver name   : uvcvideo
> Card type     : PureThermal (fw:v1.2.2): PureTh
> Bus info      : usb-ci_hdrc.1-1
> Driver version: 5.3.0
> Capabilities  : 0x84A00001
> Video Capture
> Metadata Capture
> Streaming
> Extended Pix Format
> Device Capabilities
> Device Caps   : 0x04A00000
> Metadata Capture
> Streaming
> Extended Pix Format
> Priority: 2
> root@bionic-armhf:~# v4l2-ctl --device=/dev/video10 --stream-mmap
> --stream-to=x.raw --stream-count=1
> unsupported stream type
> ^^^ no idea what this 2nd video device is
>
> I'm also not clear why the device enumerates then disconnects and
> enumerates again when plugged in but this happens on the system it
> works on as well and I've seen similar things with other devices.
>

I have found that if I enumerate the camera through a PCIe based XHCI
host controller it still registers the 2 v4l2 devices but in this case
I can capture fine. So it would appear that this has something to do
with the IMX6 ci_hdrc controller. The -ENOSPC is getting returned from
drivers/usb/host/ehci-sched.c:iso_stream_schedule()

I feel perhaps this is something basic I don't understand regarding
USB URB scheduling but I don't get why it occurs on the IMX6 ci_hdrc
controller on not an XHCI controller.

Regards,

Tim

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data may not be exported or transferred to certain countries or specified 
designated nationals identified by U.S. embargo controls without prior 
export authorization. By accepting this email and any attachments, all 
recipients confirm that they understand and will comply with all applicable 
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Re: PureThermal2 UVC video camera: Failed to submit URB 0 (-28)

[Alan Stern]

On Tue, 1 Oct 2019, Tim Harvey wrote:

> On Thu, Sep 26, 2019 at 3:47 PM Tim Harvey <tharvey@gateworks.com> wrote:
> >
> > Greetings,
> >
> > I'm running into an issue with a USB UVC Full speed camera, the
> > PureThermal2 [1] on an IMX6 based ARM board.
> >
> > What I find is that I get two video devices registered (the first one
> > is the expected device, and I'm not clear what the 2nd one is). When I
> > try to capture a single frame I get 'Failed to submit URB 0 (-28)'
> > which historically has been due to a bandwidth issue. I encounter this
> > on the IMX6 EHCI host as well as the OTG host when no other devices
> > are connected (no hubs either). I've tested with both a 4.20 kernel
> > and a 5.3 kernel.
> >
> > If I plug this device into another board I have based on an OcteonTX
> > ARM64 cpu with a fairly modern 4.14 kernel and I find that a single
> > video device gets registered and I can capture just fine.
> >
> > Here are some details:
> > lsusb reports: 1e4e:0100 Cubeternet WebCam
> >
> > working system with 4.14 kernel hot-inserting the camera:
> > [  495.163276] usb 1-1.2: new full-speed USB device number 6 using xhci_hcd
> > [  495.291685] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
> > (1e4e:0100)
> > [  495.300543] input: PureThermal (fw:v1.2.2): PureTh as
> > /devices/platform/soc@0/848000000000.pci/pci0000:00/0000:00:10.0/usb1/1-1/1-1.2/1-1.2:1.0/input/input1
> > [  496.731214] usb 1-1.2: USB disconnect, device number 6
> > [  496.987294] usb 1-1.2: new full-speed USB device number 7 using xhci_hcd
> > [  497.115683] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
> > (1e4e:0100)
> > [  497.124182] input: PureThermal (fw:v1.2.2): PureTh as
> > /devices/platform/soc@0/848000000000.pci/pci0000:00/0000:00:10.0/usb1/1-1/1-1.2/1-1.2:1.0/input/input2

...

> > I'm also not clear why the device enumerates then disconnects and
> > enumerates again when plugged in but this happens on the system it
> > works on as well and I've seen similar things with other devices.

Perhaps some process opens the camera's device file, does something to 
cause the camera to disconnect and reconnect, but then doesn't close 
the file.

> I have found that if I enumerate the camera through a PCIe based XHCI
> host controller it still registers the 2 v4l2 devices but in this case
> I can capture fine. So it would appear that this has something to do
> with the IMX6 ci_hdrc controller. The -ENOSPC is getting returned from
> drivers/usb/host/ehci-sched.c:iso_stream_schedule()
> 
> I feel perhaps this is something basic I don't understand regarding
> USB URB scheduling but I don't get why it occurs on the IMX6 ci_hdrc
> controller on not an XHCI controller.

It's probably related to differences between the drivers.  What shows 
up in /sys/kernel/debug/usb/devices with the camera plugged in?

Alan Stern

> Regards,
> 
> Tim
> 
> -- 
> 
> 
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Re: PureThermal2 UVC video camera: Failed to submit URB 0 (-28)

[Tim Harvey]

On Tue, Oct 1, 2019 at 12:19 PM Alan Stern <stern@rowland.harvard.edu> wrote:
>
> On Tue, 1 Oct 2019, Tim Harvey wrote:
>
> > On Thu, Sep 26, 2019 at 3:47 PM Tim Harvey <tharvey@gateworks.com> wrote:
> > >
> > > Greetings,
> > >
> > > I'm running into an issue with a USB UVC Full speed camera, the
> > > PureThermal2 [1] on an IMX6 based ARM board.
> > >
> > > What I find is that I get two video devices registered (the first one
> > > is the expected device, and I'm not clear what the 2nd one is). When I
> > > try to capture a single frame I get 'Failed to submit URB 0 (-28)'
> > > which historically has been due to a bandwidth issue. I encounter this
> > > on the IMX6 EHCI host as well as the OTG host when no other devices
> > > are connected (no hubs either). I've tested with both a 4.20 kernel
> > > and a 5.3 kernel.
> > >
> > > If I plug this device into another board I have based on an OcteonTX
> > > ARM64 cpu with a fairly modern 4.14 kernel and I find that a single
> > > video device gets registered and I can capture just fine.
> > >
> > > Here are some details:
> > > lsusb reports: 1e4e:0100 Cubeternet WebCam
> > >
> > > working system with 4.14 kernel hot-inserting the camera:
> > > [  495.163276] usb 1-1.2: new full-speed USB device number 6 using xhci_hcd
> > > [  495.291685] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
> > > (1e4e:0100)
> > > [  495.300543] input: PureThermal (fw:v1.2.2): PureTh as
> > > /devices/platform/soc@0/848000000000.pci/pci0000:00/0000:00:10.0/usb1/1-1/1-1.2/1-1.2:1.0/input/input1
> > > [  496.731214] usb 1-1.2: USB disconnect, device number 6
> > > [  496.987294] usb 1-1.2: new full-speed USB device number 7 using xhci_hcd
> > > [  497.115683] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
> > > (1e4e:0100)
> > > [  497.124182] input: PureThermal (fw:v1.2.2): PureTh as
> > > /devices/platform/soc@0/848000000000.pci/pci0000:00/0000:00:10.0/usb1/1-1/1-1.2/1-1.2:1.0/input/input2
>
> ...
>
> > > I'm also not clear why the device enumerates then disconnects and
> > > enumerates again when plugged in but this happens on the system it
> > > works on as well and I've seen similar things with other devices.
>
> Perhaps some process opens the camera's device file, does something to
> cause the camera to disconnect and reconnect, but then doesn't close
> the file.

Alan,

I found that the '2 devices' is because of a kernel commit in 4.16
that adds support for UVC metadata: 088ead2 media: uvcvideo: Add a
metadata device node. I can comment out the call to
uvc_meta_register() and the 2nd device goes away but the first (and
only) v4l2 capture device still has the same issue.

>
> > I have found that if I enumerate the camera through a PCIe based XHCI
> > host controller it still registers the 2 v4l2 devices but in this case
> > I can capture fine. So it would appear that this has something to do
> > with the IMX6 ci_hdrc controller. The -ENOSPC is getting returned from
> > drivers/usb/host/ehci-sched.c:iso_stream_schedule()
> >
> > I feel perhaps this is something basic I don't understand regarding
> > USB URB scheduling but I don't get why it occurs on the IMX6 ci_hdrc
> > controller on not an XHCI controller.
>
> It's probably related to differences between the drivers.  What shows
> up in /sys/kernel/debug/usb/devices with the camera plugged in?
>

Here's some more debugging including /sys/kernel/debug/usb/devices:

~# lsusb
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 1e4e:0100 Cubeternet WebCam
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
~# lsusb -d 1e4e:0100 -v

Bus 001 Device 002: ID 1e4e:0100 Cubeternet WebCam
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass          239 Miscellaneous Device
  bDeviceSubClass         2 ?
  bDeviceProtocol         1 Interface Association
  bMaxPacketSize0        64
  idVendor           0x1e4e Cubeternet
  idProduct          0x0100 WebCam
  bcdDevice            2.00
  iManufacturer           1 GroupGets
  iProduct                2 PureThermal (fw:v1.2.2)
  iSerial                 3 801f001c-5102-3038-3835-393400000000
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength          685
    bNumInterfaces          2
    bConfigurationValue     1
    iConfiguration          0
    bmAttributes         0x80
      (Bus Powered)
    MaxPower              100mA
    Interface Association:
      bLength                 8
      bDescriptorType        11
      bFirstInterface         0
      bInterfaceCount         2
      bFunctionClass         14 Video
      bFunctionSubClass       3 Video Interface Collection
      bFunctionProtocol       0
      iFunction               2 PureThermal (fw:v1.2.2)
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           1
      bInterfaceClass        14 Video
      bInterfaceSubClass      1 Video Control
      bInterfaceProtocol      0
      iInterface              0
      VideoControl Interface Descriptor:
        bLength                13
        bDescriptorType        36
        bDescriptorSubtype      1 (HEADER)
        bcdUVC               1.00
        wTotalLength          259
        dwClockFrequency        6.000000MHz
        bInCollection           1
        baInterfaceNr( 0)       1
      VideoControl Interface Descriptor:
        bLength                18
        bDescriptorType        36
        bDescriptorSubtype      2 (INPUT_TERMINAL)
        bTerminalID             1
        wTerminalType      0x0201 Camera Sensor
        bAssocTerminal          0
        iTerminal               0
        wObjectiveFocalLengthMin      0
        wObjectiveFocalLengthMax      0
        wOcularFocalLength            0
        bControlSize                  3
        bmControls           0x00000000
      VideoControl Interface Descriptor:
        bLength                12
        bDescriptorType        36
        bDescriptorSubtype      5 (PROCESSING_UNIT)
      Warning: Descriptor too short
        bUnitID                 2
        bSourceID               1
        wMaxMultiplier          0
        bControlSize            3
        bmControls     0x00000003
          Brightness
          Contrast
        iProcessing             0
        bmVideoStandards     0x1d
          None
          PAL - 625/50
          SECAM - 625/50
          NTSC - 625/50
      VideoControl Interface Descriptor:
        bLength                29
        bDescriptorType        36
        bDescriptorSubtype      6 (EXTENSION_UNIT)
        bUnitID                 3
        guidExtensionCode         {7074312d-6c65-702d-6167-632d30303030}
        bNumControl            20
        bNrPins                 1
        baSourceID( 0)          2
        bControlSize            4
        bmControls( 0)       0xff
        bmControls( 1)       0xff
        bmControls( 2)       0x0f
        bmControls( 3)       0x00
        iExtension              0
      VideoControl Interface Descriptor:
        bLength                29
        bDescriptorType        36
        bDescriptorSubtype      6 (EXTENSION_UNIT)
        bUnitID                 4
        guidExtensionCode         {7074312d-6c65-702d-6f65-6d2d30303030}
        bNumControl            30
        bNrPins                 1
        baSourceID( 0)          2
        bControlSize            4
        bmControls( 0)       0xbf
        bmControls( 1)       0xff
        bmControls( 2)       0xff
        bmControls( 3)       0x7f
        iExtension              0
      VideoControl Interface Descriptor:
        bLength                33
        bDescriptorType        36
        bDescriptorSubtype      6 (EXTENSION_UNIT)
        bUnitID                 5
        guidExtensionCode         {7074312d-6c65-702d-7261-642d30303030}
        bNumControl            48
        bNrPins                 1
        baSourceID( 0)          2
        bControlSize            8
        bmControls( 0)       0xff
        bmControls( 1)       0xff
        bmControls( 2)       0xff
        bmControls( 3)       0x81
        bmControls( 4)       0xfc
        bmControls( 5)       0xcf
        bmControls( 6)       0xff
        bmControls( 7)       0x03
        iExtension              0
      VideoControl Interface Descriptor:
        bLength                29
        bDescriptorType        36
        bDescriptorSubtype      6 (EXTENSION_UNIT)
        bUnitID                 6
        guidExtensionCode         {7074312d-6c65-702d-7379-732d30303030}
        bNumControl            23
        bNrPins                 1
        baSourceID( 0)          2
        bControlSize            4
        bmControls( 0)       0xff
        bmControls( 1)       0xff
        bmControls( 2)       0x7f
        bmControls( 3)       0x00
        iExtension              0
      VideoControl Interface Descriptor:
        bLength                29
        bDescriptorType        36
        bDescriptorSubtype      6 (EXTENSION_UNIT)
        bUnitID                 7
        guidExtensionCode         {7074312d-6c65-702d-7669-642d30303030}
        bNumControl            14
        bNrPins                 1
        baSourceID( 0)          2
        bControlSize            4
        bmControls( 0)       0xff
        bmControls( 1)       0x3f
        bmControls( 2)       0x00
        bmControls( 3)       0x00
        iExtension              0
      VideoControl Interface Descriptor:
        bLength                29
        bDescriptorType        36
        bDescriptorSubtype      6 (EXTENSION_UNIT)
        bUnitID                21
        guidExtensionCode         {7074312d-6c65-702d-7261-643230303030}
        bNumControl            27
        bNrPins                 1
        baSourceID( 0)          2
        bControlSize            4
        bmControls( 0)       0xf9
        bmControls( 1)       0x9f
        bmControls( 2)       0xff
        bmControls( 3)       0x07
        iExtension              0
      VideoControl Interface Descriptor:
        bLength                29
        bDescriptorType        36
        bDescriptorSubtype      6 (EXTENSION_UNIT)
        bUnitID               254
        guidExtensionCode         {7074312d-6c65-702d-6375-737430303030}
        bNumControl             6
        bNrPins                 1
        baSourceID( 0)          2
        bControlSize            4
        bmControls( 0)       0x3f
        bmControls( 1)       0x00
        bmControls( 2)       0x00
        bmControls( 3)       0x00
        iExtension              0
      VideoControl Interface Descriptor:
        bLength                 9
        bDescriptorType        36
        bDescriptorSubtype      3 (OUTPUT_TERMINAL)
        bTerminalID           255
        wTerminalType      0x0101 USB Streaming
        bAssocTerminal          0
        bSourceID               3
        iTerminal               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x82  EP 2 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0008  1x 8 bytes
        bInterval              32
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       0
      bNumEndpoints           0
      bInterfaceClass        14 Video
      bInterfaceSubClass      2 Video Streaming
      bInterfaceProtocol      0
      iInterface              0
      VideoStreaming Interface Descriptor:
        bLength                            18
        bDescriptorType                    36
        bDescriptorSubtype                  1 (INPUT_HEADER)
        bNumFormats                         5
        wTotalLength                      363
        bEndPointAddress                  129
        bmInfo                              0
        bTerminalLink                     255
        bStillCaptureMethod                 1
        bTriggerSupport                     0
        bTriggerUsage                       0
        bControlSize                        1
        bmaControls( 0)                    27
        bmaControls( 1)                    27
        bmaControls( 2)                    27
        bmaControls( 3)                    27
        bmaControls( 4)                    27
      VideoStreaming Interface Descriptor:
        bLength                            27
        bDescriptorType                    36
        bDescriptorSubtype                  4 (FORMAT_UNCOMPRESSED)
        bFormatIndex                        1
        bNumFrameDescriptors                1
        guidFormat
{55595659-0000-1000-8000-00aa00389b71}
        bBitsPerPixel                      16
        bDefaultFrameIndex                  1
        bAspectRatioX                       0
        bAspectRatioY                       0
        bmInterlaceFlags                 0x00
          Interlaced stream or variable: No
          Fields per frame: 2 fields
          Field 1 first: No
          Field pattern: Field 1 only
          bCopyProtect                      0
      VideoStreaming Interface Descriptor:
        bLength                            30
        bDescriptorType                    36
        bDescriptorSubtype                  5 (FRAME_UNCOMPRESSED)
        bFrameIndex                         1
        bmCapabilities                   0x02
          Still image unsupported
          Fixed frame-rate
        wWidth                            160
        wHeight                           120
        dwMinBitRate                  2764800
        dwMaxBitRate                  2764800
        dwMaxVideoFrameBufferSize       38400
        dwDefaultFrameInterval        1111111
        bFrameIntervalType                  1
        dwFrameInterval( 0)           1111111
      VideoStreaming Interface Descriptor:
        bLength                             6
        bDescriptorType                    36
        bDescriptorSubtype                 13 (COLORFORMAT)
        bColorPrimaries                     1 (BT.709,sRGB)
        bTransferCharacteristics            1 (BT.709)
        bMatrixCoefficients                 4 (SMPTE 170M (BT.601))
      VideoStreaming Interface Descriptor:
        bLength                            27
        bDescriptorType                    36
        bDescriptorSubtype                  4 (FORMAT_UNCOMPRESSED)
        bFormatIndex                        2
        bNumFrameDescriptors                2
        guidFormat
{59313620-0000-1000-8000-00aa00389b71}
        bBitsPerPixel                      16
        bDefaultFrameIndex                  1
        bAspectRatioX                       0
        bAspectRatioY                       0
        bmInterlaceFlags                 0x00
          Interlaced stream or variable: No
          Fields per frame: 2 fields
          Field 1 first: No
          Field pattern: Field 1 only
          bCopyProtect                      0
      VideoStreaming Interface Descriptor:
        bLength                            30
        bDescriptorType                    36
        bDescriptorSubtype                  5 (FRAME_UNCOMPRESSED)
        bFrameIndex                         1
        bmCapabilities                   0x02
          Still image unsupported
          Fixed frame-rate
        wWidth                            160
        wHeight                           120
        dwMinBitRate                  2764800
        dwMaxBitRate                  2764800
        dwMaxVideoFrameBufferSize       38400
        dwDefaultFrameInterval        1111111
        bFrameIntervalType                  1
        dwFrameInterval( 0)           1111111
      VideoStreaming Interface Descriptor:
        bLength                            30
        bDescriptorType                    36
        bDescriptorSubtype                  5 (FRAME_UNCOMPRESSED)
        bFrameIndex                         2
        bmCapabilities                   0x02
          Still image unsupported
          Fixed frame-rate
        wWidth                            160
        wHeight                           122
        dwMinBitRate                  2810880
        dwMaxBitRate                  2810880
        dwMaxVideoFrameBufferSize       39040
        dwDefaultFrameInterval        1111111
        bFrameIntervalType                  1
        dwFrameInterval( 0)           1111111
      VideoStreaming Interface Descriptor:
        bLength                             6
        bDescriptorType                    36
        bDescriptorSubtype                 13 (COLORFORMAT)
        bColorPrimaries                     1 (BT.709,sRGB)
        bTransferCharacteristics            1 (BT.709)
        bMatrixCoefficients                 4 (SMPTE 170M (BT.601))
      VideoStreaming Interface Descriptor:
        bLength                            27
        bDescriptorType                    36
        bDescriptorSubtype                  4 (FORMAT_UNCOMPRESSED)
        bFormatIndex                        3
        bNumFrameDescriptors                1
        guidFormat
{59382020-0000-1000-8000-00aa00389b71}
        bBitsPerPixel                       8
        bDefaultFrameIndex                  1
        bAspectRatioX                       0
        bAspectRatioY                       0
        bmInterlaceFlags                 0x00
          Interlaced stream or variable: No
          Fields per frame: 2 fields
          Field 1 first: No
          Field pattern: Field 1 only
          bCopyProtect                      0
      VideoStreaming Interface Descriptor:
        bLength                            30
        bDescriptorType                    36
        bDescriptorSubtype                  5 (FRAME_UNCOMPRESSED)
        bFrameIndex                         1
        bmCapabilities                   0x02
          Still image unsupported
          Fixed frame-rate
        wWidth                            160
        wHeight                           120
        dwMinBitRate                  1382400
        dwMaxBitRate                  1382400
        dwMaxVideoFrameBufferSize       19200
        dwDefaultFrameInterval        1111111
        bFrameIntervalType                  1
        dwFrameInterval( 0)           1111111
      VideoStreaming Interface Descriptor:
        bLength                             6
        bDescriptorType                    36
        bDescriptorSubtype                 13 (COLORFORMAT)
        bColorPrimaries                     1 (BT.709,sRGB)
        bTransferCharacteristics            1 (BT.709)
        bMatrixCoefficients                 4 (SMPTE 170M (BT.601))
      VideoStreaming Interface Descriptor:
        bLength                            27
        bDescriptorType                    36
        bDescriptorSubtype                  4 (FORMAT_UNCOMPRESSED)
        bFormatIndex                        4
        bNumFrameDescriptors                1
        guidFormat
{52474250-0000-1000-8000-00aa00389b71}
        bBitsPerPixel                      16
        bDefaultFrameIndex                  1
        bAspectRatioX                       0
        bAspectRatioY                       0
        bmInterlaceFlags                 0x00
          Interlaced stream or variable: No
          Fields per frame: 2 fields
          Field 1 first: No
          Field pattern: Field 1 only
          bCopyProtect                      0
      VideoStreaming Interface Descriptor:
        bLength                            30
        bDescriptorType                    36
        bDescriptorSubtype                  5 (FRAME_UNCOMPRESSED)
        bFrameIndex                         1
        bmCapabilities                   0x02
          Still image unsupported
          Fixed frame-rate
        wWidth                            160
        wHeight                           120
        dwMinBitRate                  2764800
        dwMaxBitRate                  2764800
        dwMaxVideoFrameBufferSize       38400
        dwDefaultFrameInterval        1111111
        bFrameIntervalType                  1
        dwFrameInterval( 0)           1111111
      VideoStreaming Interface Descriptor:
        bLength                             6
        bDescriptorType                    36
        bDescriptorSubtype                 13 (COLORFORMAT)
        bColorPrimaries                     1 (BT.709,sRGB)
        bTransferCharacteristics            1 (BT.709)
        bMatrixCoefficients                 4 (SMPTE 170M (BT.601))
      VideoStreaming Interface Descriptor:
        bLength                            27
        bDescriptorType                    36
        bDescriptorSubtype                  4 (FORMAT_UNCOMPRESSED)
        bFormatIndex                        5
        bNumFrameDescriptors                1
        guidFormat
{7deb36e4-4f52-ce11-9f53-0020af0ba770}
        bBitsPerPixel                      24
        bDefaultFrameIndex                  1
        bAspectRatioX                       0
        bAspectRatioY                       0
        bmInterlaceFlags                 0x00
          Interlaced stream or variable: No
          Fields per frame: 2 fields
          Field 1 first: No
          Field pattern: Field 1 only
          bCopyProtect                      0
      VideoStreaming Interface Descriptor:
        bLength                            30
        bDescriptorType                    36
        bDescriptorSubtype                  5 (FRAME_UNCOMPRESSED)
        bFrameIndex                         1
        bmCapabilities                   0x02
          Still image unsupported
          Fixed frame-rate
        wWidth                            160
        wHeight                           120
        dwMinBitRate                  4147200
        dwMaxBitRate                  4147200
        dwMaxVideoFrameBufferSize       57600
        dwDefaultFrameInterval        1111111
        bFrameIntervalType                  1
        dwFrameInterval( 0)           1111111
      VideoStreaming Interface Descriptor:
        bLength                             6
        bDescriptorType                    36
        bDescriptorSubtype                 13 (COLORFORMAT)
        bColorPrimaries                     1 (BT.709,sRGB)
        bTransferCharacteristics            1 (BT.709)
        bMatrixCoefficients                 4 (SMPTE 170M (BT.601))
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       1
      bNumEndpoints           1
      bInterfaceClass        14 Video
      bInterfaceSubClass      2 Video Streaming
      bInterfaceProtocol      0
      iInterface              0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            1
          Transfer Type            Isochronous
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x03c2  1x 962 bytes
        bInterval               1
Device Status:     0x0000
  (Bus Powered)
~# for i in $(ls -1d /sys/class/video4linux/video*); do echo $i:$(cat
$i/name); done
/sys/class/video4linux/video0:PureThermal (fw:v1.2.2): PureTh
/sys/class/video4linux/video1:ipu1_csi0 capture
/sys/class/video4linux/video2:ipu1_ic_prpenc capture
/sys/class/video4linux/video3:ipu1_ic_prpvf capture
/sys/class/video4linux/video4:ipu1_csi1 capture
/sys/class/video4linux/video5:ipu2_csi0 capture
/sys/class/video4linux/video6:ipu2_ic_prpenc capture
/sys/class/video4linux/video7:ipu2_ic_prpvf capture
/sys/class/video4linux/video8:ipu2_csi1 capture
/sys/class/video4linux/video9:ipu_ic_pp csc/scaler
~# v4l2-ctl --device /dev/video0 --stream-mmap --stream-to=x.raw
--stream-count=1
[   82.433385] uvcvideo: uvc_v4l2_open
[   82.449716] uvcvideo: uvc_v4l2_mmap
[   82.453767] uvcvideo: uvc_v4l2_mmap
[   82.457408] uvcvideo: uvc_v4l2_mmap
[   82.460983] uvcvideo: uvc_v4l2_mmap
[   82.466275] uvcvideo: Device requested 962 B/frame bandwidth.
[   82.472579] uvcvideo: Selecting alternate setting 1 (962 B/frame bandwidth).
[   82.485634] uvcvideo: Allocated 5 URB buffers of 32x962 bytes each.
[   82.492431] ci_hdrc ci_hdrc.0: iso sched full 399d9fef
[   82.497845] uvcvideo: Failed to submit URB 0 (-28).
VIDIOC_STREAMON: failed: No space left on device
[   82.511215] uvcvideo: uvc_v4l2_release
~# cat /sys/kernel/debug/usb/devices

T:  Bus=01 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=480  MxCh= 1
B:  Alloc=  0/800 us ( 0%), #Int=  0, #Iso=  0
D:  Ver= 2.00 Cls=09(hub  ) Sub=00 Prot=01 MxPS=64 #Cfgs=  1
P:  Vendor=1d6b ProdID=0002 Rev= 5.03
S:  Manufacturer=Linux 5.3.0-00157-g651f7f9-dirty ehci_hcd
S:  Product=EHCI Host Controller
S:  SerialNumber=ci_hdrc.0
C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=  0mA
I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub
E:  Ad=81(I) Atr=03(Int.) MxPS=   4 Ivl=256ms

T:  Bus=01 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#=  2 Spd=12   MxCh= 0
D:  Ver= 2.00 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs=  1
P:  Vendor=1e4e ProdID=0100 Rev= 2.00
S:  Manufacturer=GroupGets
S:  Product=PureThermal (fw:v1.2.2)
S:  SerialNumber=801f001c-5102-3038-3835-393400000000
C:* #Ifs= 2 Cfg#= 1 Atr=80 MxPwr=100mA
A:  FirstIf#= 0 IfCount= 2 Cls=0e(video) Sub=03 Prot=00
I:* If#= 0 Alt= 0 #EPs= 1 Cls=0e(video) Sub=01 Prot=00 Driver=uvcvideo
E:  Ad=82(I) Atr=03(Int.) MxPS=   8 Ivl=32ms
I:* If#= 1 Alt= 0 #EPs= 0 Cls=0e(video) Sub=02 Prot=00 Driver=uvcvideo
I:  If#= 1 Alt= 1 #EPs= 1 Cls=0e(video) Sub=02 Prot=00 Driver=uvcvideo
E:  Ad=81(I) Atr=01(Isoc) MxPS= 962 Ivl=1ms

T:  Bus=02 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=480  MxCh= 1
B:  Alloc=  0/800 us ( 0%), #Int=  0, #Iso=  0
D:  Ver= 2.00 Cls=09(hub  ) Sub=00 Prot=01 MxPS=64 #Cfgs=  1
P:  Vendor=1d6b ProdID=0002 Rev= 5.03
S:  Manufacturer=Linux 5.3.0-00157-g651f7f9-dirty ehci_hcd
S:  Product=EHCI Host Controller
S:  SerialNumber=ci_hdrc.1
C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=  0mA
I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub
E:  Ad=81(I) Atr=03(Int.) MxPS=   4 Ivl=256ms

~# [  224.159009] systemd-journald[278]: Sent WATCHDOG=1 notification.
v4l2-ctl --device /dev/video0 --all
[  283.767759] uvcvideo: uvc_v4l2_open
Driver Info (not using libv4l2):
        Driver name   : uvcvideo
        Car[  283.777534] systemd-journald[278]: Sent WATCHDOG=1 notification.
d type     : PureThermal (fw:v1.2[  283.785714] uvcvideo: uvc_v4l2_release
.2): PureTh
        Bus info      : usb-ci_hdrc.0-1
        Driver version: 5.3.0
        Capabilities  : 0x84A00001
                Video Capture
                Metadata Capture
                Streaming
                Extended Pix Format
                Device Capabilities
        Device Caps   : 0x04200001
                Video Capture
                Streaming
                Extended Pix Format
Priority: 2
Video input : 0 (Camera 1: ok)
Format Video Capture:
        Width/Height      : 160/120
        Pixel Format      : 'UYVY'
        Field             : None
        Bytes per Line    : 320
        Size Image        : 38400
        Colorspace        : sRGB
        Transfer Function : Default (maps to sRGB)
        YCbCr/HSV Encoding: Default (maps to ITU-R 601)
        Quantization      : Default (maps to Limited Range)
        Flags             :
Crop Capability Video Capture:
        Bounds      : Left 0, Top 0, Width 160, Height 120
        Default     : Left 0, Top 0, Width 160, Height 120
        Pixel Aspect: 1/1
Selection: crop_default, Left 0, Top 0, Width 160, Height 120
Selection: crop_bounds, Left 0, Top 0, Width 160, Height 120
Streaming Parameters Video Capture:
        Capabilities     : timeperframe
        Frames per second: 9.000 (9/1)
        Read buffers     : 0
                     brightness 0x00980900 (int)    : min=0 max=255
step=1 default=128 value=128
                       contrast 0x00980901 (int)    : min=0 max=255
step=1 default=128 value=128

So regardless of resolution/frame-size the device is requesting 962
byte USB frame bandwidth which should be just fine for USB full speed
in iso mode (max 1023). I'm not sure why the bandwidth reservation
fails.

Apparently the RaspberryPi 4 has this same issue:
https://github.com/raspberrypi/linux/issues/3136. The same thread
mentions that most USB full speed devices have fall-back endpoint
max-packet sizes that allow for reduced bandwidth reservations (but
this camera does not).

I get the same results regardless of CONFIG_USB_EHCI_TT_NEWSCHED enabled or not.

<snip>
>
> PS: These notices are completely inappropriate for a messages sent to a
> public mailing list.  If adhered to strictly, they would prevent anyone
> from replying to your message.
>

sorry about the sig... IT department inserted that via our mail server
and I didn't realize it was in use. Problem resolved.

Tim

Re: PureThermal2 UVC video camera: Failed to submit URB 0 (-28)

[Alan Stern]

On Wed, 2 Oct 2019, Tim Harvey wrote:

> On Tue, Oct 1, 2019 at 12:19 PM Alan Stern <stern@rowland.harvard.edu> wrote:
> >
> > On Tue, 1 Oct 2019, Tim Harvey wrote:
> >
> > > On Thu, Sep 26, 2019 at 3:47 PM Tim Harvey <tharvey@gateworks.com> wrote:
> > > >
> > > > Greetings,
> > > >
> > > > I'm running into an issue with a USB UVC Full speed camera, the
> > > > PureThermal2 [1] on an IMX6 based ARM board.
> > > >
> > > > What I find is that I get two video devices registered (the first one
> > > > is the expected device, and I'm not clear what the 2nd one is). When I
> > > > try to capture a single frame I get 'Failed to submit URB 0 (-28)'
> > > > which historically has been due to a bandwidth issue. I encounter this
> > > > on the IMX6 EHCI host as well as the OTG host when no other devices
> > > > are connected (no hubs either). I've tested with both a 4.20 kernel
> > > > and a 5.3 kernel.
> > > >
> > > > If I plug this device into another board I have based on an OcteonTX
> > > > ARM64 cpu with a fairly modern 4.14 kernel and I find that a single
> > > > video device gets registered and I can capture just fine.
> > > >
> > > > Here are some details:
> > > > lsusb reports: 1e4e:0100 Cubeternet WebCam
> > > >
> > > > working system with 4.14 kernel hot-inserting the camera:
> > > > [  495.163276] usb 1-1.2: new full-speed USB device number 6 using xhci_hcd
> > > > [  495.291685] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
> > > > (1e4e:0100)
> > > > [  495.300543] input: PureThermal (fw:v1.2.2): PureTh as
> > > > /devices/platform/soc@0/848000000000.pci/pci0000:00/0000:00:10.0/usb1/1-1/1-1.2/1-1.2:1.0/input/input1
> > > > [  496.731214] usb 1-1.2: USB disconnect, device number 6
> > > > [  496.987294] usb 1-1.2: new full-speed USB device number 7 using xhci_hcd
> > > > [  497.115683] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
> > > > (1e4e:0100)
> > > > [  497.124182] input: PureThermal (fw:v1.2.2): PureTh as
> > > > /devices/platform/soc@0/848000000000.pci/pci0000:00/0000:00:10.0/usb1/1-1/1-1.2/1-1.2:1.0/input/input2
> >
> > ...
> >
> > > > I'm also not clear why the device enumerates then disconnects and
> > > > enumerates again when plugged in but this happens on the system it
> > > > works on as well and I've seen similar things with other devices.
> >
> > Perhaps some process opens the camera's device file, does something to
> > cause the camera to disconnect and reconnect, but then doesn't close
> > the file.
> 
> Alan,
> 
> I found that the '2 devices' is because of a kernel commit in 4.16
> that adds support for UVC metadata: 088ead2 media: uvcvideo: Add a
> metadata device node. I can comment out the call to
> uvc_meta_register() and the 2nd device goes away but the first (and
> only) v4l2 capture device still has the same issue.

Okay, that explains that.

> > > I have found that if I enumerate the camera through a PCIe based XHCI
> > > host controller it still registers the 2 v4l2 devices but in this case
> > > I can capture fine. So it would appear that this has something to do
> > > with the IMX6 ci_hdrc controller. The -ENOSPC is getting returned from
> > > drivers/usb/host/ehci-sched.c:iso_stream_schedule()
> > >
> > > I feel perhaps this is something basic I don't understand regarding
> > > USB URB scheduling but I don't get why it occurs on the IMX6 ci_hdrc
> > > controller on not an XHCI controller.
> >
> > It's probably related to differences between the drivers.  What shows
> > up in /sys/kernel/debug/usb/devices with the camera plugged in?
> >
> 
> Here's some more debugging including /sys/kernel/debug/usb/devices:
> ~# cat /sys/kernel/debug/usb/devices
> 
> T:  Bus=01 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=480  MxCh= 1
> B:  Alloc=  0/800 us ( 0%), #Int=  0, #Iso=  0
> D:  Ver= 2.00 Cls=09(hub  ) Sub=00 Prot=01 MxPS=64 #Cfgs=  1
> P:  Vendor=1d6b ProdID=0002 Rev= 5.03
> S:  Manufacturer=Linux 5.3.0-00157-g651f7f9-dirty ehci_hcd
> S:  Product=EHCI Host Controller
> S:  SerialNumber=ci_hdrc.0
> C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=  0mA
> I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub
> E:  Ad=81(I) Atr=03(Int.) MxPS=   4 Ivl=256ms
> 
> T:  Bus=01 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#=  2 Spd=12   MxCh= 0
> D:  Ver= 2.00 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs=  1
> P:  Vendor=1e4e ProdID=0100 Rev= 2.00
> S:  Manufacturer=GroupGets
> S:  Product=PureThermal (fw:v1.2.2)
> S:  SerialNumber=801f001c-5102-3038-3835-393400000000
> C:* #Ifs= 2 Cfg#= 1 Atr=80 MxPwr=100mA
> A:  FirstIf#= 0 IfCount= 2 Cls=0e(video) Sub=03 Prot=00
> I:* If#= 0 Alt= 0 #EPs= 1 Cls=0e(video) Sub=01 Prot=00 Driver=uvcvideo
> E:  Ad=82(I) Atr=03(Int.) MxPS=   8 Ivl=32ms
> I:* If#= 1 Alt= 0 #EPs= 0 Cls=0e(video) Sub=02 Prot=00 Driver=uvcvideo
> I:  If#= 1 Alt= 1 #EPs= 1 Cls=0e(video) Sub=02 Prot=00 Driver=uvcvideo
> E:  Ad=81(I) Atr=01(Isoc) MxPS= 962 Ivl=1ms

So the camera is the only device on the bus (aside from the root hub).  
And it asks for an 8-byte interrupt endpoint together with a 962-byte
isochronous endpoint.

That explains the problem.  ehci-hcd (the same code manages ChipIdea
controllers) doesn't do a good job of handling high-bandwidth periodic
requests for full-speed devices, particularly when isochronous and
interrupt endpoints are both present.

> So regardless of resolution/frame-size the device is requesting 962
> byte USB frame bandwidth which should be just fine for USB full speed
> in iso mode (max 1023). I'm not sure why the bandwidth reservation
> fails.

Yes, that amount of data is fine for full-speed USB.  But handling 
full-speed devices attached to a high-speed controller isn't easy, and 
ehci-hcd isn't able to make use of all the possible bandwidth.  In 
fact, you'd be better off attaching the camera to a full-speed USB 1.1 
controller, if one were available for your system.

xHCI controllers, on the other hand, handle all the scheduling issues
in hardware so the driver doesn't have to deal with them.  Evidently
the ones you tried don't have any trouble in this situation.

> Apparently the RaspberryPi 4 has this same issue:
> https://github.com/raspberrypi/linux/issues/3136. The same thread
> mentions that most USB full speed devices have fall-back endpoint
> max-packet sizes that allow for reduced bandwidth reservations (but
> this camera does not).
> 
> I get the same results regardless of CONFIG_USB_EHCI_TT_NEWSCHED enabled or not.

And indeed, the same problem will occur whenever this device is 
attached to an EHCI controller on a Linux-based system, unless somebody 
goes to the trouble of improving the driver.  (It's tremendously 
complicated -- the spec puts almost all the burden on the software 
rather than the hardware/firmware -- and probably not worth the effort 
of trying to do it correctly.  I wouldn't be surprised if adding proper 
support for this would double the size of the driver.)

Alan Stern

Re: PureThermal2 UVC video camera: Failed to submit URB 0 (-28)

[Tim Harvey]

On Wed, Oct 2, 2019 at 10:58 AM Alan Stern <stern@rowland.harvard.edu> wrote:
>
> On Wed, 2 Oct 2019, Tim Harvey wrote:
>
> > On Tue, Oct 1, 2019 at 12:19 PM Alan Stern <stern@rowland.harvard.edu> wrote:
> > >
> > > On Tue, 1 Oct 2019, Tim Harvey wrote:
> > >
> > > > On Thu, Sep 26, 2019 at 3:47 PM Tim Harvey <tharvey@gateworks.com> wrote:
> > > > >
> > > > > Greetings,
> > > > >
> > > > > I'm running into an issue with a USB UVC Full speed camera, the
> > > > > PureThermal2 [1] on an IMX6 based ARM board.
> > > > >
> > > > > What I find is that I get two video devices registered (the first one
> > > > > is the expected device, and I'm not clear what the 2nd one is). When I
> > > > > try to capture a single frame I get 'Failed to submit URB 0 (-28)'
> > > > > which historically has been due to a bandwidth issue. I encounter this
> > > > > on the IMX6 EHCI host as well as the OTG host when no other devices
> > > > > are connected (no hubs either). I've tested with both a 4.20 kernel
> > > > > and a 5.3 kernel.
> > > > >
> > > > > If I plug this device into another board I have based on an OcteonTX
> > > > > ARM64 cpu with a fairly modern 4.14 kernel and I find that a single
> > > > > video device gets registered and I can capture just fine.
> > > > >
> > > > > Here are some details:
> > > > > lsusb reports: 1e4e:0100 Cubeternet WebCam
> > > > >
> > > > > working system with 4.14 kernel hot-inserting the camera:
> > > > > [  495.163276] usb 1-1.2: new full-speed USB device number 6 using xhci_hcd
> > > > > [  495.291685] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
> > > > > (1e4e:0100)
> > > > > [  495.300543] input: PureThermal (fw:v1.2.2): PureTh as
> > > > > /devices/platform/soc@0/848000000000.pci/pci0000:00/0000:00:10.0/usb1/1-1/1-1.2/1-1.2:1.0/input/input1
> > > > > [  496.731214] usb 1-1.2: USB disconnect, device number 6
> > > > > [  496.987294] usb 1-1.2: new full-speed USB device number 7 using xhci_hcd
> > > > > [  497.115683] uvcvideo: Found UVC 1.00 device PureThermal (fw:v1.2.2)
> > > > > (1e4e:0100)
> > > > > [  497.124182] input: PureThermal (fw:v1.2.2): PureTh as
> > > > > /devices/platform/soc@0/848000000000.pci/pci0000:00/0000:00:10.0/usb1/1-1/1-1.2/1-1.2:1.0/input/input2
> > >
> > > ...
> > >
> > > > > I'm also not clear why the device enumerates then disconnects and
> > > > > enumerates again when plugged in but this happens on the system it
> > > > > works on as well and I've seen similar things with other devices.
> > >
> > > Perhaps some process opens the camera's device file, does something to
> > > cause the camera to disconnect and reconnect, but then doesn't close
> > > the file.
> >
> > Alan,
> >
> > I found that the '2 devices' is because of a kernel commit in 4.16
> > that adds support for UVC metadata: 088ead2 media: uvcvideo: Add a
> > metadata device node. I can comment out the call to
> > uvc_meta_register() and the 2nd device goes away but the first (and
> > only) v4l2 capture device still has the same issue.
>
> Okay, that explains that.
>
> > > > I have found that if I enumerate the camera through a PCIe based XHCI
> > > > host controller it still registers the 2 v4l2 devices but in this case
> > > > I can capture fine. So it would appear that this has something to do
> > > > with the IMX6 ci_hdrc controller. The -ENOSPC is getting returned from
> > > > drivers/usb/host/ehci-sched.c:iso_stream_schedule()
> > > >
> > > > I feel perhaps this is something basic I don't understand regarding
> > > > USB URB scheduling but I don't get why it occurs on the IMX6 ci_hdrc
> > > > controller on not an XHCI controller.
> > >
> > > It's probably related to differences between the drivers.  What shows
> > > up in /sys/kernel/debug/usb/devices with the camera plugged in?
> > >
> >
> > Here's some more debugging including /sys/kernel/debug/usb/devices:
> > ~# cat /sys/kernel/debug/usb/devices
> >
> > T:  Bus=01 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=480  MxCh= 1
> > B:  Alloc=  0/800 us ( 0%), #Int=  0, #Iso=  0
> > D:  Ver= 2.00 Cls=09(hub  ) Sub=00 Prot=01 MxPS=64 #Cfgs=  1
> > P:  Vendor=1d6b ProdID=0002 Rev= 5.03
> > S:  Manufacturer=Linux 5.3.0-00157-g651f7f9-dirty ehci_hcd
> > S:  Product=EHCI Host Controller
> > S:  SerialNumber=ci_hdrc.0
> > C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=  0mA
> > I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub
> > E:  Ad=81(I) Atr=03(Int.) MxPS=   4 Ivl=256ms
> >
> > T:  Bus=01 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#=  2 Spd=12   MxCh= 0
> > D:  Ver= 2.00 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs=  1
> > P:  Vendor=1e4e ProdID=0100 Rev= 2.00
> > S:  Manufacturer=GroupGets
> > S:  Product=PureThermal (fw:v1.2.2)
> > S:  SerialNumber=801f001c-5102-3038-3835-393400000000
> > C:* #Ifs= 2 Cfg#= 1 Atr=80 MxPwr=100mA
> > A:  FirstIf#= 0 IfCount= 2 Cls=0e(video) Sub=03 Prot=00
> > I:* If#= 0 Alt= 0 #EPs= 1 Cls=0e(video) Sub=01 Prot=00 Driver=uvcvideo
> > E:  Ad=82(I) Atr=03(Int.) MxPS=   8 Ivl=32ms
> > I:* If#= 1 Alt= 0 #EPs= 0 Cls=0e(video) Sub=02 Prot=00 Driver=uvcvideo
> > I:  If#= 1 Alt= 1 #EPs= 1 Cls=0e(video) Sub=02 Prot=00 Driver=uvcvideo
> > E:  Ad=81(I) Atr=01(Isoc) MxPS= 962 Ivl=1ms
>
> So the camera is the only device on the bus (aside from the root hub).
> And it asks for an 8-byte interrupt endpoint together with a 962-byte
> isochronous endpoint.
>
> That explains the problem.  ehci-hcd (the same code manages ChipIdea
> controllers) doesn't do a good job of handling high-bandwidth periodic
> requests for full-speed devices, particularly when isochronous and
> interrupt endpoints are both present.
>
> > So regardless of resolution/frame-size the device is requesting 962
> > byte USB frame bandwidth which should be just fine for USB full speed
> > in iso mode (max 1023). I'm not sure why the bandwidth reservation
> > fails.
>
> Yes, that amount of data is fine for full-speed USB.  But handling
> full-speed devices attached to a high-speed controller isn't easy, and
> ehci-hcd isn't able to make use of all the possible bandwidth.  In
> fact, you'd be better off attaching the camera to a full-speed USB 1.1
> controller, if one were available for your system.
>
> xHCI controllers, on the other hand, handle all the scheduling issues
> in hardware so the driver doesn't have to deal with them.  Evidently
> the ones you tried don't have any trouble in this situation.
>
> > Apparently the RaspberryPi 4 has this same issue:
> > https://github.com/raspberrypi/linux/issues/3136. The same thread
> > mentions that most USB full speed devices have fall-back endpoint
> > max-packet sizes that allow for reduced bandwidth reservations (but
> > this camera does not).
> >
> > I get the same results regardless of CONFIG_USB_EHCI_TT_NEWSCHED enabled or not.
>
> And indeed, the same problem will occur whenever this device is
> attached to an EHCI controller on a Linux-based system, unless somebody
> goes to the trouble of improving the driver.  (It's tremendously
> complicated -- the spec puts almost all the burden on the software
> rather than the hardware/firmware -- and probably not worth the effort
> of trying to do it correctly.  I wouldn't be surprised if adding proper
> support for this would double the size of the driver.)
>

Alan,

Thanks for explaining this - its incredibly helpful!

Tim

Re: PureThermal2 UVC video camera: Failed to submit URB 0 (-28)

[Greg KH]

On Tue, Oct 01, 2019 at 11:58:26AM -0700, Tim Harvey wrote:
> CONFIDENTIALITY NOTICE: This email constitutes an electronic 
> communication within the meaning of the Electronic Communications Privacy 
> Act, 18 U.S.C. 2510, and its disclosure is strictly limited to the named 
> recipient(s) intended by the sender of this message. This email, and any 
> attachments, may contain confidential and/or proprietary information. If 
> you are not a named recipient, any copying, using, disclosing or 
> distributing to others the information in this email and attachments is 
> STRICTLY PROHIBITED. If you have received this email in error, please 
> notify the sender immediately and permanently delete the email, any 
> attachments, and all copies thereof from any drives or storage media and 
> destroy any printouts or hard copies of the email and attachments.

Now destroyed.  Footers like this are one way to not get a response on a
public mailing list :(