USB Host No longer works, Please help! :(
 

I've searched the forums but can't find any solutions to this particular problem:

When I go into usb host mode on my n810 (latest version of Diablo) using usbcontrol I immediately get one warning that the usb device is not supported even though I haven't plugged anything in yet. Then when I do plug in a USB device nothing happens. I've tried different usb control apps, I've tried re-flashing which hasn't helped, I also tried pluging the n810 in b mode into a computer and then turning host mode on as suggested in one of the threads about a kernel issue with the n810 but nothing has worked. Does anyone have any idea whats wrong, could it be a hardware problem? (although the n810 mounts fine as a usb drive on my desktop).

Attached is what I get from dmesg

Re: USB Host No longer works
 

Looking through the dmesg I found this:

VBUS_ERROR in a_wait_vrise (91, <VBusValid), retry #1, port1 00000100
[ 170.484375] tusb_otg_ints 837: vbus too slow, devctl 91
[ 170.484375] tusb_source_power 633: VBUS a_wait_vfall, devctl 90 otg 154 conf c0000001 prcm 00a80500
[ 171.062500] tusb_source_power 633: VBUS a_idle

Does anyone know what this means?

Re: USB Host No longer works
 

I used a multimeter to check the power output of the usb port and when I select host mode immediately the voltage rises and falls in about half a second. At the same time it says usb device not supported even though no device is plugged in then it goes to a_idle and I get no voltage out of the usb port and no usb devices work. :mad:

Re: USB Host No longer works
 

Argh! This is really aggravating! Maybe I should just RMA my n810 and get a new one though I'm not sure they'd be too happy to replace a device which has a problem with an unadvertised feature. I wish I could figure out whether this is a hardware or a software issue. :(

Could any of you linux gurus explain to me what this vbus error could possibly mean? Thanks! :)

Re: USB Host No longer works
 

Why is no one answering? :( Is everyone as clueless about this as me?

Re: USB Host No longer works
 

I am sorry to see that you have not yet had a response to your post. Sometimes It is not apparent to the members of this forum what your problem is. On the other hand, I have had someone respond within 5 minutes. I have been using "usbcontrol" and "eggtimer" for many months and suddenly they do not even run. I read this forum every single day of the week and catch some very interesting posts that are extremely helpful. Keep posting your problems and be patient. :)

Re: USB Host No longer works
 

Ok, some developments:

I decided to reflash again since i have nothing to lose and the very first app I install is usbcontrol but when I tap on the icon to launch it nothing happens.

Then I installed the cpu load tray icon and rootsh and I try running usbcontrol again and again nothing happens and the cpu stays almost idle the whole time.

So I run usbcontrol from xterm with normal rights and it says that permission is denied to create new modes in '/sys/devices/platform/musb_hdrc/mode' and the usbcontrol ui loads but tapping the change mode buttons don't work so I run usbcontrol again with root priviledges and then it loads but the hildon style buttons are not loaded, it just has the generic linux skin which I wouldn't mind so much if it worked but it doesn't, I get the same vbus error that I explained in my above posts with the 'usb device not supported' popup appearing even before I plug in a device. So back to square one.

I reflash a second time and go through exactly the same thing as above so I reflash a third time and instead install the alternative usb-otg-plugin which installed and ran without any problems but still I have the same vbus problem.

I was wondering about the reflashing process: does it repartition the internal memory (not internal memory card) before rewriting the operating system files or does it just overwrite the system files with fresh ones? If it is the later then I was thinking that there might be a corrupted driver for the USB port and the reflash is not removing it which could be why I'm still having problems. If it is the former then it must be some kind of hardware problem because I can't see how else it could survive a reflash unless it is some problem with the really low level firmware of the usb controler.

Re: USB Host No longer works
 

I tried using xterm and also got the "permission denied" message.

Re: USB Host No longer works
 

That's because you should become root by using "root" (check extras) or R&D (not recommended), not by using sudo or su (which will not properly set the environment vars).

It makes no sense to "repartition" the internal flash (partition limits are hardcoded). It does overwrite the initfs (were drivers/kernel modules are) and the rootfs (rest of the system), but not the config area; I don't know if the config area hosts anything related with usb config.

Re: USB Host No longer works
 

Good to know this, before I was doing:

1.) sudo gainroot

enter

2.) usbcontrol

So now I see that all I have to do is type root to get a root shell (you can probably see I'm a total n00b when it comes to linux! ;) )

Thanks!

I see. I could have phrased it better when I said that; what I meant is whether the whole flash area is wiped but according to you it seems that this is not the case.

Could I then delete everything in the config area and then reflash? How do I go about doing this? Again, as you can see I'm not very experienced with linux but I know enough to find my way through the filesystem in terminal.

Thanks!

Re: USB Host No longer works
 

My expertise on this subject is so minimal as to be nonexistant, but I think you might be wise to ignore the "usb device not supported" message. I get this message every time I switch to host mode, using USB Control, whether a device is connected or not. And while some devices don't work, others do, despite the warning.

The N810 does seem to be very picky about which flash drives it will deal with. Some work, some don't, but all are greeted with the "usb device not supported" message.

Please note, this is just my experience, and not necessarily what others have experienced. I am NOT claiming that you don't have a problem, only that the "device not supported" message may be irrelevant to diagnosing and correcting the problem.

Re: USB Host No longer works
 

No worries RobbH, I used to get that all the time when it was working, this is because there is a list of devices that the tablet "officially supports" and so it shows this error even though the device works. But as of a few days ago I've had a problem where as soon as I switch to host mode before I have plugged anything in I immediately get a usb device not supported error pop up once as if there is some phantom device plugged in, then when I do plug in the usb device (ive tried loads of devices that used to work before: multiple flash drives, usb keyboards even my mobile phone) nothing happens at all, the usb device gets no power whatsoever so my tablet never realises its there. I have a feeling that for some reason or other the usb controller is unable to raise the voltage of the port to the requisite 5 volts in order to power the device because whenever I switch to host mode it always says in dmesg that there was an error in a_wait_vrise and that the vbus is too slow.

Re: USB Host No longer works
 

I tried reflashing my n810 with an older chinook firmware 1.2007.42-18 and I still have exactly the same problem where I can't get any usb device to work. I'm starting to think that this is a hardware problem.

Do you think I should just return my n810 for a replacement and be done with it?