Message ID | 20210628155311.16762-2-m.grzeschik@pengutronix.de (mailing list archive) |
---|---|
State | Accepted |
Commit | c6e23b89a95db73bb85be28079664c66389323f0 |
Headers | show |
Series | usb: gadget: uvc: improve uvc gadget performance | expand |
On Mon, Jun 28, 2021 at 05:53:07PM +0200, Michael Grzeschik wrote: > In case of dwc3 it is possible that the sysdev is the parent of the > controller. To ensure the right dev is set to the gadget's dev parent we > will hand over sysdev instead of dev, which will always point to the > controller. > > Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de> > > --- > -> v2: first version of patch > -> v3: - > --- > drivers/usb/dwc3/gadget.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c > index af6d7f157989d..8a1b1daff2e97 100644 > --- a/drivers/usb/dwc3/gadget.c > +++ b/drivers/usb/dwc3/gadget.c > @@ -3990,7 +3990,7 @@ int dwc3_gadget_init(struct dwc3 *dwc) > } > > > - usb_initialize_gadget(dwc->dev, dwc->gadget, dwc_gadget_release); > + usb_initialize_gadget(dwc->sysdev, dwc->gadget, dwc_gadget_release); Does this change how the device shows up in sysfs? Why does the parent not always work properly here? thanks, greg k-h
Hi, Greg KH <greg@kroah.com> writes: > On Mon, Jun 28, 2021 at 05:53:07PM +0200, Michael Grzeschik wrote: >> In case of dwc3 it is possible that the sysdev is the parent of the >> controller. To ensure the right dev is set to the gadget's dev parent we >> will hand over sysdev instead of dev, which will always point to the >> controller. >> >> Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de> >> >> --- >> -> v2: first version of patch >> -> v3: - >> --- >> drivers/usb/dwc3/gadget.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c >> index af6d7f157989d..8a1b1daff2e97 100644 >> --- a/drivers/usb/dwc3/gadget.c >> +++ b/drivers/usb/dwc3/gadget.c >> @@ -3990,7 +3990,7 @@ int dwc3_gadget_init(struct dwc3 *dwc) >> } >> >> >> - usb_initialize_gadget(dwc->dev, dwc->gadget, dwc_gadget_release); >> + usb_initialize_gadget(dwc->sysdev, dwc->gadget, dwc_gadget_release); > > Does this change how the device shows up in sysfs? it might, but not in all instances of dwc3 > Why does the parent not always work properly here? This is a really old commit by Arnd from back in 2016 (d64ff406e51e) where it was noticed that dwc3's dma ops weren't properly setup. Arnd decided to pass a property to tell dwc3 core to use the parent device for dma operations. This is not required in all instances of dwc3, though.
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index af6d7f157989d..8a1b1daff2e97 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -3990,7 +3990,7 @@ int dwc3_gadget_init(struct dwc3 *dwc) } - usb_initialize_gadget(dwc->dev, dwc->gadget, dwc_gadget_release); + usb_initialize_gadget(dwc->sysdev, dwc->gadget, dwc_gadget_release); dev = &dwc->gadget->dev; dev->platform_data = dwc; dwc->gadget->ops = &dwc3_gadget_ops;
In case of dwc3 it is possible that the sysdev is the parent of the controller. To ensure the right dev is set to the gadget's dev parent we will hand over sysdev instead of dev, which will always point to the controller. Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de> --- -> v2: first version of patch -> v3: - --- drivers/usb/dwc3/gadget.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)