Re: [PATCH v2 2/3] usb: chipidea: Hook into mux framework to toggle usb switch

From: Stephen Boyd
Date: Tue Jul 18 2017 - 21:50:30 EST


Quoting Peter Chen (2017-07-17 21:41:11)
> On Fri, Jul 14, 2017 at 02:40:04PM -0700, Stephen Boyd wrote:
> >
> > @@ -175,6 +176,10 @@ static int host_start(struct ci_hdrc *ci)
> > if (ci_otg_is_fsm_mode(ci)) {
> > otg->host = &hcd->self;
> > hcd->self.otg_port = 1;
> > + } else {
> > + ret = mux_control_select(ci->platdata->usb_switch, 1);
>
> It is better to use MACRO for 1 and 0.
>

Ok.

> > + if (ret)
> > + goto disable_reg;
> > }
> > }
> >
> > @@ -195,6 +200,8 @@ static void host_stop(struct ci_hdrc *ci)
> > struct usb_hcd *hcd = ci->hcd;
> >
> > if (hcd) {
> > + if (!ci_otg_is_fsm_mode(ci))
> > + mux_control_deselect(ci->platdata->usb_switch);
> > if (ci->platdata->notify_event)
> > ci->platdata->notify_event(ci,
> > CI_HDRC_CONTROLLER_STOPPED_EVENT);
> > diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c
> > index d68b125796f9..deb18099e168 100644
> > --- a/drivers/usb/chipidea/udc.c
> > +++ b/drivers/usb/chipidea/udc.c
> > @@ -22,6 +22,7 @@
> > #include <linux/usb/gadget.h>
> > #include <linux/usb/otg-fsm.h>
> > #include <linux/usb/chipidea.h>
> > +#include <linux/mux/consumer.h>
> >
> > #include "ci.h"
> > #include "udc.h"
> > @@ -1964,16 +1965,26 @@ void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
> >
> > static int udc_id_switch_for_device(struct ci_hdrc *ci)
> > {
> > + int ret = 0;
> > +
> > if (ci->is_otg)
> > /* Clear and enable BSV irq */
> > hw_write_otgsc(ci, OTGSC_BSVIS | OTGSC_BSVIE,
> > OTGSC_BSVIS | OTGSC_BSVIE);
> >
> > - return 0;
> > + if (!ci_otg_is_fsm_mode(ci))
> > + ret = mux_control_select(ci->platdata->usb_switch, 0);
> > +
> > + if (ci->is_otg && ret)
> > + hw_write_otgsc(ci, OTGSC_BSVIE | OTGSC_BSVIS, OTGSC_BSVIS);
>
> Should use !ret?
>

No? This is intended to unwind the clearing and enabling of the BSV irq
on failure (ret is non-zero) and so we clear and disable the BSV irq.