View unanswered posts | View active topics It is currently Sun May 19, 2019 6:25 am



Reply to topic  [ 5 posts ] 
 utilite-1 OTG doesn't work as USB-peripheral 
Author Message

Joined: Sat Sep 10, 2016 11:40 am
Posts: 1
Post utilite-1 OTG doesn't work as USB-peripheral
The utilite-1 device isn't recognized as peripheral device if connected to the host computer via OTG port.

I've loaded g_ether and g_serial on the utilite device but none of them worked.
I've tested it with both kernels (3.0.35 and 3.10).

/proc/driver/*udc on uitlite reports the state "a_idle".
But I've inserted a USB micro-b plug into the OTG receptacle of the utilite device, so it has to behave as a B-Device not as an A-Device.

Any sugesstions?

Regards,
Rupert


Fri Sep 16, 2016 6:22 am
Profile

Joined: Sat May 14, 2016 1:24 pm
Posts: 56
Post Re: utilite-1 OTG doesn't work as USB-peripheral
Hi Rupert,

I can tell you that both peripheral and host mode work fine with Linux 4.7 and 4.8-rc5 on the Utilite Pro but I don't have /proc/driver/*udc available. So most probably Linux (i.e. upstream) uses another or improved otg driver.

What you might want to try:
1) (the obvious) make sure your cable works (try it with another otg device/use another cable),

2) plug your device in *after* your OS is completely up & running. The bootloader configures the otg controller in host only mode. There is a chance that the OS driver does only switch the role on a plug event.

2) make sure dual role/otg is enabled in the kernel config as well as the device tree (in the config most otg controllers can be fixed to either host or peripheral mode). In the device tree there should be a "dr_mode" property (see e.g. here https://github.com/vcspth/linux/blob/ut ... 6.dts#L280 ).

3) try to force the controller into peripheral mode (be cautious, this may damage your hardware). Some otg drivers allow this via proc/sysfs.

4) Use an upstream kernel if you can go without DVI/Sound/Wifi/Bt/gpu acceleration/VPU support.
EDIT: 4) is only applicable if you have the Utilite Pro; for the other models there is no upstream support, yet (or let's say its very hackish).

Good luck!
Christopher


Sat Sep 17, 2016 5:26 pm
Profile

Joined: Tue Jan 07, 2014 12:07 am
Posts: 138
Location: Edinburgh, Scotland
Post Re: utilite-1 OTG doesn't work as USB-peripheral
I got it to work fairly easily with a mainline(ish) 4.8.16 kernel. I just had to disable CONFIG_USB_OTG_WHITELIST. I now have a 64GB LVM volume served up as an external drive for my Wii U. :D


Sun Jan 08, 2017 5:03 pm
Profile

Joined: Wed Jun 21, 2017 12:33 pm
Posts: 1
Post Re: utilite-1 OTG doesn't work as USB-peripheral
I've got basically the same Problem as described above. Unfortunately chris' solutions don't help me/aren't suitable for me.

Has anyone other suggestions?

Regarding what chewi wrote: Isn't CONFIG_USB_OTG_WHITELIST just restricting which devices are allowed to be a peripheral, when the utilite is acting as host? So how does it influence wether the utilite is recognized as peripheral itself or not? I'm very curios about that :)

I'm grateful for any piece of information, that is helping.

Regards
Mari


Wed Jun 21, 2017 1:57 pm
Profile

Joined: Tue Jan 07, 2014 12:07 am
Posts: 138
Location: Edinburgh, Scotland
Post Re: utilite-1 OTG doesn't work as USB-peripheral
Sorry, must have missed this. You've probably solved this or given up by now but I was also confused by the CONFIG_USB_OTG_WHITELIST option. I didn't expect it to help but it did.


Wed Jan 03, 2018 11:38 am
Profile
Display posts from previous:  Sort by  
Reply to topic   [ 5 posts ] 

Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group.
Designed by STSoftware for PTF.