Charging USB devices with Fedora

[Rick Stevens]

On 3/17/10 12:29 PM, Ambrogio wrote:
> Il giorno mer, 17/03/2010 alle 12.58 +0100, NoSpaze ha scritto:
>
>
>> I cant' understand if you are able to charge also from the wall power
>> adapter. Anyway, it doesn't seem to be a linux issue; could be:
>>
> I also think it's not a Linux issue, because I'm unable to charge them
> with a wall power adapter.
> The wall adapter was sold by the same vendor, saying that it's good
> enough for all devices ;-)
>
>
>> - Cable damaged
>>
> I used different cables, starting from the 2 embedded with the devices.
>
>
>> - Charging from PC is not possible on both devices (if they are chinese,
>> I can bet on it).
>>
> They are sold with the specific feature. It can be charged only with USB
> adapter.
>
>
>> - USB card damaged
>>
> I tried with 2 different PC, with every USB port.
> The port seams to works very well with a lot of periferals (also USB HD
> without power).
>
>
>> - MP3 devices require some software signal to start charge (look for
>> software)
>>
> One of them is sold with a CD, but the software is only for upload new
> firmware and is only for windows (not vista).
> The other is sold without software.
>
>
>> - Some BIOS options on the devices can able the USB port to
>> enable/disable charging when mounted (just try unmounting and wait or
>> looking for configuratio options on devices).
>>
> One of them has only 5 keys, no display, nothing that suggest special
> functions.
>
> Now I don't have anymore the devices, so I can consider closed the
> issue.
> My children will remain without mp3 player for now :-D
>
> But this is a very strange quirk.
>
It really isn't.  By default, the USB libraries leave the USB ports in
low power mode.  Many devices (e.g. Blackberrys) require more power
than that.  In the case of a Blackberry, the barry libraries and udev
rulesets kick the USB port into high-power mode to charge it.

Is there a way to force high power to all USB ports...not that I know
of.