Re: [PATCH v10 5/5] usb: dwc3: core: cleanup IRQ resources

[Sergei Shtylyov]

On 6/10/2016 2:35 PM, Roger Quadros wrote:
> On 10/06/16 13:39, Sergei Shtylyov wrote:
> > Hello.
> >
> > On 6/10/2016 12:56 PM, Roger Quadros wrote:
> >
> > > Implementations might use different IRQs for
> > > host, gadget so use named interrupt resources
> > > to allow device tree to specify the interrupts.
> > >
> > > Following are the interrupt names
> > >
> > > Peripheral Interrupt - peripheral
> > > HOST Interrupt - host
> > >
> > > Maintain backward compatibility for a single named
> > > interrupt ("dwc3_usb3") for all interrupts as well as
> > > unnamed interrupt at index 0 for all interrupts.
> > >
> > > As platform_get_irq_() variants are used, tackle
> >
> >    platform_get_irq().
>
> OK.
> > > the -EPROBE_DEFER case as well.
> > >
> > > Signed-off-by: Roger Quadros <rogerq@xxxxxx>
> > > ---
> > > v10:
> > > - don't mention otg irq since we are not using it yet
> > > - use platform_get_irq() and friends and check -EPROBE_DEFER case.
> > >
> > >  drivers/usb/dwc3/core.c   | 22 ++++++++--------------
> > >  drivers/usb/dwc3/gadget.c | 29 ++++++++++++++++++++++++++---
> > >  drivers/usb/dwc3/host.c   | 41 ++++++++++++++++++++++++++++++++++++++++-
> > >  3 files changed, 74 insertions(+), 18 deletions(-)
> > >
> > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> > > index 8fceeb1..131e7eb 100644
> > > --- a/drivers/usb/dwc3/core.c
> > > +++ b/drivers/usb/dwc3/core.c
> > [...]
> > > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> > > index 0f6fb8e..774a0d8 100644
> > > --- a/drivers/usb/dwc3/gadget.c
> > > +++ b/drivers/usb/dwc3/gadget.c
> > [...]
> > > @@ -2866,7 +2865,31 @@ static irqreturn_t dwc3_interrupt(int irq, void *_evt)
> > >   */
> > >  int dwc3_gadget_init(struct dwc3 *dwc)
> > >  {
> > > -    int                    ret;
> > > +    int ret, irq;
> > > +    struct platform_device *dwc3_pdev = to_platform_device(dwc->dev);
> > > +
> > > +    irq = platform_get_irq_byname(dwc3_pdev, "peripheral");
> > > +    if (irq == -EPROBE_DEFER)
> > > +        return irq;
> > > +
> > > +    if (irq <= 0) {
> > > +        irq = platform_get_irq_byname(dwc3_pdev, "dwc_usb3");
> > > +        if (irq == -EPROBE_DEFER)
> > > +            return irq;
> > > +
> > > +        if (irq <= 0) {
> > > +            irq = platform_get_irq(dwc3_pdev, 0);
> > > +            if (irq <= 0) {
> > > +                if (irq != -EPROBE_DEFER) {
> > > +                    dev_err(dwc->dev,
> > > +                        "missing peripheral IRQ\n");
> > > +                }
> > > +                return irq;
> >
> >    Iff irq == 0, you'll return success despite IRQ was "invalid". Was that intended?
>
> good catch. It wasn't intended. I guess i'll return -EINVAL then?
>
> > > +            }
> > > +        }
> > > +    }
> > > +
> > > +    dwc->irq_gadget = irq;
> > >
> > >      dwc->ctrl_req = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
> > >              &dwc->ctrl_req_addr, GFP_KERNEL);
> > > diff --git a/drivers/usb/dwc3/host.c b/drivers/usb/dwc3/host.c
> > > index c679f63..eb5e8f9 100644
> > > --- a/drivers/usb/dwc3/host.c
> > > +++ b/drivers/usb/dwc3/host.c
> > > @@ -24,7 +24,46 @@ int dwc3_host_init(struct dwc3 *dwc)
> > >  {
> > >      struct platform_device    *xhci;
> > >      struct usb_xhci_pdata    pdata;
> > > -    int            ret;
> > > +    int            ret, irq;
> > > +    struct resource        *res;
> > > +    struct platform_device    *dwc3_pdev = to_platform_device(dwc->dev);
> > > +
> > > +    irq = platform_get_irq_byname(dwc3_pdev, "host");
> > > +    if (irq == -EPROBE_DEFER)
> > > +        return irq;
> > > +
> > > +    if (irq <= 0) {
> > > +        irq = platform_get_irq_byname(dwc3_pdev, "dwc_usb3");
> > > +        if (irq == -EPROBE_DEFER)
> > > +            return irq;
> > > +
> > > +        if (irq <= 0) {
> > > +            irq = platform_get_irq(dwc3_pdev, 0);
> > > +            if (irq <= 0) {
> > > +                if (irq != -EPROBE_DEFER) {
> > > +                    dev_err(dwc->dev,
> > > +                        "missing host IRQ\n");
> > > +                }
> > > +                return irq;
> >
> >    Iff irq == 0, you'll return success despite IRQ was "invalid". Was that intended?

   I'd just consider 0 a valid IRQ, that's simpler. FYI, I've submitted to 
Greg KH a patch fixing platform_get_irq[_byname]() to not return 0 on failure. 
No reaction so far...

> --
> cheers,
> -roger

MBR, Sergei