Re: [PATCH v3 5/5] usb: musb: da8xx: Remove set_mode callback

[Bin Liu]

On Thu, Nov 03, 2016 at 12:18:53PM -0500, David Lechner wrote:
> On 11/03/2016 10:26 AM, Alexandre Bailon wrote:
> >The USB PHY is able to operate in OTG, host or peripheral.
> >Some board may be wired to work act only as host or peripheral.
> >In such case, the dr_mode property of controller must be set to
> >host or peripheral. But doing that will also configure the PHY
> >in host or peripheral mode whereas OTG is able to detect which
> >role the USB controller should take.
> >The PHY's host or peripheral mode are actually only useful when
> >hardware doesn't allow OTG to detect it's role.
> >
> >The set_mode callback is used by the musb driver to set mode
> >of the PHY. But in the case of DA8xx, the PHY have some issues.
> >The OTG mode work correctly but the host and peripheral don't.
> >In host mode, the PHY stops to work after the first disconnect.
> >In device mode, the PHY doesn't detect any disconnect.
> >As the OTG mode is working properly, let the PHY in OTG mode,
> >whatever is the controller mode.
> >
> >Signed-off-by: Alexandre Bailon <abailon@xxxxxxxxxxxx>
> >---
> > drivers/usb/musb/da8xx.c | 23 -----------------------
> > 1 file changed, 23 deletions(-)
> >
> >diff --git a/drivers/usb/musb/da8xx.c b/drivers/usb/musb/da8xx.c
> >index 6749aa1..581f830 100644
> >--- a/drivers/usb/musb/da8xx.c
> >+++ b/drivers/usb/musb/da8xx.c
> >@@ -335,28 +335,6 @@ static irqreturn_t da8xx_musb_interrupt(int irq, void *hci)
> > 	return ret;
> > }
> >
> >-static int da8xx_musb_set_mode(struct musb *musb, u8 musb_mode)
> 
> Bin suggested using some sort of quirks flag. So instead of removing
> this callback, I think this is where to incorporate the quirks
> flags.
> 
> I suppose the quirks could be kernel config options. Perhaps someone
> else has a better idea?

I didn't closely follow this thread, but I was thinking about to reuse
musb->io.quirks, and define the quirks in device tree...

I am debugging an issue in dsps, and might need a quirk for the
solution...

Regards,
-Bin.