[U-Boot] [PATCH 2/2] musb: sunxi: Implement dfu_usb_get_reset()

[Marek Vasut]

On Sunday, October 25, 2015 at 03:55:43 PM, Siarhei Siamashka wrote:
> On Sun, 25 Oct 2015 12:00:09 +0100
> 
> Marek Vasut <marex at denx.de> wrote:
> > On Sunday, October 25, 2015 at 05:44:47 AM, Siarhei Siamashka wrote:
> > > This is necessary to distinguish between the "dfu-util --detach" and
> > > the "dfu-util --reset" requests.
> > > 
> > > The default weak implementation of dfu_usb_get_reset() unconditionally
> > > reboots the device, but we want to be able to continue the boot.scr
> > > execution after writing the kernel, fdt and ramdisk to RAM via DFU.
> > > 
> > > Signed-off-by: Siarhei Siamashka <siarhei.siamashka at gmail.com>
> > > ---
> > > 
> > >  drivers/usb/musb-new/sunxi.c | 12 ++++++++++++
> > >  1 file changed, 12 insertions(+)
> > > 
> > > diff --git a/drivers/usb/musb-new/sunxi.c
> > > b/drivers/usb/musb-new/sunxi.c index a146c08..5eb8d19 100644
> > > --- a/drivers/usb/musb-new/sunxi.c
> > > +++ b/drivers/usb/musb-new/sunxi.c
> > > @@ -166,6 +166,17 @@ static void USBC_ConfigFIFO_Base(void)
> > > 
> > >  }
> > >  
> > >  /*********************************************************************
> > >  ****
> > > 
> > > ***** + * Needed for the DFU polling magic
> > > +
> > > ***********************************************************************
> > > *** ****/ +
> > > +static u8 last_int_usb;
> > > +
> > > +bool dfu_usb_get_reset(void)
> > > +{
> > > +	return !!(last_int_usb & MUSB_INTR_RESET);
> > 
> > The !! is not needed.
> 
> Thanks for your comment, I can surely change this in the updated
> version of the patch.
> 
> But I'm more interested to know if the USB people are happy with the
> current wacky way of interaction between the DFU code and the USB
> drivers. Doing dfu_usb_get_reset() polling up to 1000 times in a loop
> does not look exactly beautiful:
> 
>     https://github.com/u-boot/u-boot/blob/v2015.10/common/cmd_dfu.c#L64
> 
> It might be also a bit racy (the RESET interrupt could be potentially
> missed sometimes).

That's a question for Lukasz .

Best regards,
Marek Vasut