CDC ACM driver not creating devices under /dev

Hi,

I am working on custom carrier board based on Tx1. I have connected wwan module on pcie bus.
Data path is through pcie and control path through USB.
Pcie is not able to detect the device, getting following error when i issue rescan command to pcie

[17755.497251] pcieport 0000:00:01.0: PCIe Bus Error: severity=Uncorrected (Non-Fatal), type=Transaction Layer, id=0008(Requester ID)
[17755.510628] pcieport 0000:00:01.0: device [10de:0fae] error status/mask=00004000/00000000
[17755.519258] pcieport 0000:00:01.0: [14] Completion Timeout (First)
root@tegra-ubuntu:/home/ubuntu# [17755.527025] pcieport 0000:00:02.0: PCIe Bus Error: severity=Uncorrected (Non-Fatal), type=Transaction Layer, id=0010(Requester ID)
[17755.541318] pcieport 0000:00:02.0: device [10de:0faf] error status/mask=00004000/00000000
[17755.549705] pcieport 0000:00:02.0: [14] Completion Timeout (First)

But i see device being detected in USB enumeration.
Also cdc-acm driver is also able to detect device but i could not see the device in /dev
following are the logs
[ 3.989195] usbcore: registered new interface driver cdc_ether
[ 4.006634] usbcore: registered new interface driver cdc_subset
[ 4.024276] usbcore: registered new interface driver cdc_ncm
[ 4.057222] usbcore: registered new interface driver cdc_acm
[ 4.062890] cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters
[ 4.071114] usbcore: registered new interface driver cdc_wdm
[ 16.695288] cdc_acm 1-4:1.0: This device cannot do calls on its own. It is not a modem.
[ 16.705067] cdc_acm 1-4:1.0: ttyACM0: USB ACM device
[ 16.711061] cdc_acm 1-4:1.2: This device cannot do calls on its own. It is not a modem.
[ 16.719938] cdc_acm 1-4:1.2: ttyACM1: USB ACM device
[ 16.723014] cdc_acm 1-4:1.4: This device cannot do calls on its own. It is not a modem.
[ 16.732108] cdc_acm 1-4:1.4: ttyACM2: USB ACM device
[ 16.746735] cdc_ncm 1-4:1.6 wwan0: register ‘cdc_ncm’ at usb-tegra-xhci-4, Mobile Broadband Network Device (NO ARP), 00:00:11:12:13:14
[ 16.757500] cdc_ncm 1-4:1.8 wwan1: register ‘cdc_ncm’ at usb-tegra-xhci-4, Mobile Broadband Network Device (NO ARP), 00:00:11:12:13:16
[ 16.763879] cdc_ncm 1-4:1.10 wwan2: register ‘cdc_ncm’ at usb-tegra-xhci-4, Mobile Broadband Network Device (NO ARP), 00:00:11:12:13:18
[ 16.770659] cdc_ncm 1-4:1.12 wwan3: register ‘cdc_ncm’ at usb-tegra-xhci-4, Mobile Broadband Network Device (NO ARP), 00:00:11:12:13:1a
[ 25.420638] cdc_ncm 1-4:1.6 wwan0: unregister ‘cdc_ncm’ usb-tegra-xhci-4, Mobile Broadband Network Device (NO ARP)
[ 25.477124] cdc_ncm 1-4:1.8 wwan1: unregister ‘cdc_ncm’ usb-tegra-xhci-4, Mobile Broadband Network Device (NO ARP)
[ 25.547368] cdc_ncm 1-4:1.10 wwan2: unregister ‘cdc_ncm’ usb-tegra-xhci-4, Mobile Broadband Network Device (NO ARP)
[ 25.607291] cdc_ncm 1-4:1.12 wwan3: unregister ‘cdc_ncm’ usb-tegra-xhci-4, Mobile Broadband Network Device (NO ARP)

Does anyone have idea how to resolve this??

Thanks,
Prathamesh

Is it the PCIe rescan that you are talking about here?
Can you please give the command used?
Completion timeout suggests that the device is not responding. Although I don’t clearly understand what kind of device is it, are we doing everything that is supposed to be done to make this device respond to requests coming from host?

Hi Vidyas

Thanks for replay.
Following is the command I am talking about
echo 1 > /sys/bus/pci/rescan
I have applied patch as mentioned i this post
https://devtalk.nvidia.com/default/topic/997845/jetson-tx1/force-rescan-of-pcie-bus-/

Is there anything that needs to be changed in device tree?

Thanks,
Prathamesh

patyarahate,

Are you using rel-24.2.1 or rel-28.1 now?

Hi

I am using rel24.1. is there issue with this release?
Or any patches available

Thanks,
Prathamesh

Please try to follow this thread. This should help, though it is based on rel-28.1

https://devtalk.nvidia.com/default/topic/1029901/

Hi,

After disabling USB autosuspend, i could get ttyACM devices under /dev directory.
Able to talk to device through ttyACM interface.
I am using rel 24.2.1 only.

Thanks,
Prathamesh