RE: [PATCH] musb: fix power field to hold all possible values

Gupta, Ajay Kumar
2010-02-26T04:33:10Z

Hi,
> -----Original Message-----
> From: Tony Lindgren [mailto:tony@atomide.com]
> Sent: Friday, February 26, 2010 3:50 AM
> To: Felipe Balbi
> Cc: Gupta, Ajay Kumar; linux-omap@vger.kernel.org
> Subject: Re: [PATCH] musb: fix power field to hold all possible values
>
> * Felipe Balbi <me@felipebalbi.com> [100223 12:30]:
> > Hi,
> >
> > On Tue, Feb 23, 2010 at 08:01:50PM +0530, Gupta, Ajay Kumar wrote:
> > > Board files are providing the actual mA and it is getting divided in
> > > Arch/arm/mach-omap2/usb-musb.c. See the code snippet below,
> > >
> > > musb_plat.clock = "ick";
> > > musb_plat.board_data = board_data;
> > > --> musb_plat.power = board_data->power >> 1;
> > > musb_plat.mode = board_data->mode;
> > >
> > > So we need to either take this patch or fix this logic of dividing the
> mA
> > > supplied from all omap board files.
> >
> > that's true, had missed that. Sorry.
>
> Hmm, I believe this value is also divided somewhere else but
> I forgot where. In any case, when making changes like this
> please run the standard USB tests for gadgets and OTG.
>
> Otherwise things are guaranteed to break for USB certs :)

Tony,

Currently the flow is,

1. Actual mA provided in all omap board files.
2. mA gets divided in usb-musb.c
3. mA multiplied by two in driver/usb/musb/musb_core.c to pass it to
hcd->power_budget.

So the current patch fixes the logic in step [1] above to fill mA value
Above 255.

-Ajay
>
> Tony