fat: handle Windows formatted partition (thru USB Mass Storage)

[AKASHI Takahiro]

On Fri, Jan 17, 2020 at 11:47:03AM +0200, Andy Shevchenko wrote:
> On Fri, Jan 17, 2020 at 8:13 AM AKASHI Takahiro
> <takahiro.akashi at linaro.org> wrote:
> > On Thu, Jan 16, 2020 at 10:31:49PM +0200, Andy Shevchenko wrote:
> 
> ...
> 
> > > Prerequisites:
> > >  - the board with U-Boot and installed Linux OS on eMMC
> > >  - g_multi module in Linux OS that shares *one of the eMMC partitions*
> > > (pay attention here) as a disk to Windows host
> >
> > I also misunderstood your assumption above; You are developing
> > a linux-based USB gadget for Windows (10)?
> 
> No.

Really? I've got messed up now.
- Why do you need to use g_multi to access the disk?
- Where is a disk attached to?
- Are Linux and Windows running on the same board?

-Takahiro Akashi

> > > Now, when you format that exposed disk (which is actually a partition
> > > on eMMC!) in Windows, you will get nested partitioning.
> >
> > So why do you want to access *that* partition from U-Boot on the board?
> > I don't think it is a common case.
> 
> What I'm trying to do is to copy some bootables to that partition from
> Windows machine in order to boot them via U-Boot.
> That's allow me not to disturb stock image on that board.
> 
> If U-Boot is not going to support nested partitioning, perhaps I can
> submit a documentation fix to advertise this explicitly.
> 
> -- 
> With Best Regards,
> Andy Shevchenko