using the openmoko neo101 in mass storage mode

martin-o23533 at martin-o23533 at
Wed Jun 4 18:42:35 CEST 2008

On Wed, Jun 04, 2008 at 07:29:27AM +0100, Andy Green wrote:
> Hash: SHA1
> Somebody in the thread at some point said:
> | I think we could get around with pretending to be a digital camera / media
> | player instead. IIRC the protocol prefered by windows for these is more
> | like a file server protocol (i.e. commands at file level) although maybe
> | windows doesn't allow to download files from media players and may not
> | allow to upload on cameras.
> | But that should get around the exclusive access problem.
> |


> The thing that bothers me is the effective requirement to force unmount
> the filesystem either way.  It's for sure you wanted that filesystem
> mounted in the device when it isn't presented as mass storage gadget, so
> it limits you to scenarios where you never hold the files in there open
> long term.  

Sorry if i was not clear. I didn't have time to google the exact protocol.
But i was suggesting to explore PTP/MTP as alternative protocol to usb


|> A main reason for using MTP rather than for example the USB mass storage
|> device class is that the latter operates at the granularity of a mass
|> storage device block (usually in practice, a FAT block), rather than at the
|> logical file level. In other words, the USB mass storage class is designed
|> to give a host computer undifferentiated access to bulk mass storage, such
|> as compact flash, rather than to a file system, which might be safely
|> shared with the target device (except for specific files which the host
|> might be modifying/accessing). In practice, therefore, when a USB host
|> computer has mounted an MSC partition, it assumes absolute control of the
|> storage, which then may not be safely modified without risk of data
|> corruption until the host computer has severed the connection[citation
|> needed]. 
|> MTP and PTP specifically overcome this issue by making the unit of
|> managed storage a local file rather than an entire (possibly very large)
|> unit of mass storage at the block level. 

While this protocol seems to be hated by many users, it seems to be saner
for modern devices. But i don't know how usable windows presents this for
normal file storage. And it seems to depend on software i wouldn't suggest
installing on windows... But still it's worth a thought, because it would
work without unmounting anything.

 - Martin

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