Modify the usb power budget in OSK?

Modify the usb power budget in OSK?

[Li Weichen]

Hi all,

I am trying to plug a D-Link DWL-G122 802.11g wlan usb stick on to OSK.  But
I always get the "over power budget" warning, should I modify the power
budget set in drivers/usb/host/ohci-omap.c?  Has anyone ever succeeded to
utilize a similar usb stick?

And, I have tried to use a extra wire to get power supply from a PC usb
port, the errors were still.

I am so eagerly looking forward to your help, thank you in advance.

Best regards!


Li Weichen

Re: Modify the usb power budget in OSK

[Djordje Nijemcevic]

Hello,

We have the same problem with our web camera... We're using an external
power supply for USB.

First, we modified the line in ohci-omap.c
ohci_to_hcd(ohci)->power_budget = 250;
to
ohci_to_hcd(ohci)->power_budget = 500;

After that modification, during the boot process, we still got the message
"400mA over 100mA budget"
By searching the files containing string "mA budget", we have found inside
hub.c

		/* 100mA per-port ceiling, or 8mA for OTG ports */
		if (i != (udev->bus->otg_port - 1) || hdev->parent)
			ceiling = 50;
		else
			ceiling = 4;

In the rest of the source, the value 'ceiling' is considered as a half the
maximum power that the USB port can give. After modifying the 'ceiling'
value from 50 (which corresponds to 100mA) to 250 (corresponds to 500mA)
we didn't have the boot message mentioned anymore, but the camera still
doesn't work, nor its LED :( But, you might give a try with this.

It looks strange to me that hub.c is even needed, as well as there is
100mA limit inside of it. We still doubt that our camera doesn't work due
to some power budget-related issue. Is something else to be modified?

TIA
Djordje Nijemcevic

> Hi all,
>
> I am trying to plug a D-Link DWL-G122 802.11g wlan usb stick on to OSK.
> But
> I always get the "over power budget" warning, should I modify the power
> budget set in drivers/usb/host/ohci-omap.c?  Has anyone ever succeeded to
> utilize a similar usb stick?
>
> And, I have tried to use a extra wire to get power supply from a PC usb
> port, the errors were still.
>
> I am so eagerly looking forward to your help, thank you in advance.
>
> Best regards!
>
>
> Li Weichen
>
> _______________________________________________
> Linux-omap-open-source mailing list
> Linux-omap-open-source@linux.omap.com
> http://linux.omap.com/mailman/listinfo/linux-omap-open-source
>

Re: Modify the usb power budget in OSK

[Madis Listak]

Hello,
I still have "over budget" message annoying me,
but my cameras started to work then I compiled
all the modules into the kernel and stopped using
modprobe or insmod modules.
You can try the following:

Device Drivers --->
Multimedia deices --->
<*> Video for Linux				( CONFIG_VIDEO_DEV )

Device Drivers --->
USB support --->
<*> Support for Host-side USB			( CONFIG_USB )
<*>   OHCI HCD support				( CONFIG_USB_OHCI_HCD )

Device Drivers --->
USB support --->
USB Camera support-->
<*>   USB SN9C10x PC Camera Controler support 	( CONFIG_USB_SN9C102 )

Madis


Djordje Nijemcevic wrote:

>Hello,
>
>We have the same problem with our web camera... We're using an external
>power supply for USB.
>
>First, we modified the line in ohci-omap.c
>ohci_to_hcd(ohci)->power_budget = 250;
>to
>ohci_to_hcd(ohci)->power_budget = 500;
>
>After that modification, during the boot process, we still got the message
>"400mA over 100mA budget"
>By searching the files containing string "mA budget", we have found inside
>hub.c
>
>		/* 100mA per-port ceiling, or 8mA for OTG ports */
>		if (i != (udev->bus->otg_port - 1) || hdev->parent)
>			ceiling = 50;
>		else
>			ceiling = 4;
>
>In the rest of the source, the value 'ceiling' is considered as a half the
>maximum power that the USB port can give. After modifying the 'ceiling'
>value from 50 (which corresponds to 100mA) to 250 (corresponds to 500mA)
>we didn't have the boot message mentioned anymore, but the camera still
>doesn't work, nor its LED :( But, you might give a try with this.
>
>It looks strange to me that hub.c is even needed, as well as there is
>100mA limit inside of it. We still doubt that our camera doesn't work due
>to some power budget-related issue. Is something else to be modified?
>
>TIA
>Djordje Nijemcevic
>
>  
>
>>Hi all,
>>
>>I am trying to plug a D-Link DWL-G122 802.11g wlan usb stick on to OSK.
>>But
>>I always get the "over power budget" warning, should I modify the power
>>budget set in drivers/usb/host/ohci-omap.c?  Has anyone ever succeeded to
>>utilize a similar usb stick?
>>
>>And, I have tried to use a extra wire to get power supply from a PC usb
>>port, the errors were still.
>>
>>I am so eagerly looking forward to your help, thank you in advance.
>>
>>Best regards!
>>
>>
>>Li Weichen
>>
>>_______________________________________________
>>Linux-omap-open-source mailing list
>>Linux-omap-open-source@linux.omap.com
>>http://linux.omap.com/mailman/listinfo/linux-omap-open-source
>>
>>    
>>
>
>_______________________________________________
>Linux-omap-open-source mailing list
>Linux-omap-open-source@linux.omap.com
>http://linux.omap.com/mailman/listinfo/linux-omap-open-source
>
>
>  
>