RE: [PATCH] drivers: usb: dwc3 : Configure DMA properties and ops from DT

From: Rajesh Bhagat
Date: Tue May 10 2016 - 23:45:57 EST




> -----Original Message-----
> From: Felipe Balbi [mailto:felipe.balbi@xxxxxxxxxxxxxxx]
> Sent: Wednesday, May 04, 2016 1:28 PM
> To: Rajesh Bhagat <rajesh.bhagat@xxxxxxx>; linux-usb@xxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx; gregkh@xxxxxxxxxxxxxxxxxxx; Yang-Leo Li
> <leoyang.li@xxxxxxx>; Sriram Dash <sriram.dash@xxxxxxx>; Rajesh Bhagat
> <rajesh.bhagat@xxxxxxx>
> Subject: Re: [PATCH] drivers: usb: dwc3 : Configure DMA properties and ops from DT
>
>
> Hi,
>
> Rajesh Bhagat <rajesh.bhagat@xxxxxxx> writes:
> > On certain platforms (e.g. ARM64) the dma_ops needs to be explicitly
> > set to be able to do DMA allocations, so use the of_dma_configure()
> > helper to populate the dma properties and assign an appropriate dma_ops.
> >
> > Signed-off-by: Rajesh Bhagat <rajesh.bhagat@xxxxxxx>
> > Reviewed-by: Yang-Leo Li <leoyang.li@xxxxxxx>

Hi,

>
> Cool, nxp is also using dwc3 :-) C'mon Rajesh, send us a glue layer :)
>

I would surely be sending the glue layer soon :)

> > diff --git a/drivers/usb/dwc3/host.c b/drivers/usb/dwc3/host.c index
> > c679f63..4d5b783 100644
> > --- a/drivers/usb/dwc3/host.c
> > +++ b/drivers/usb/dwc3/host.c
> > @@ -17,6 +17,7 @@
> >
> > #include <linux/platform_device.h>
> > #include <linux/usb/xhci_pdriver.h>
> > +#include <linux/of_device.h>
> >
> > #include "core.h"
> >
> > @@ -32,6 +33,9 @@ int dwc3_host_init(struct dwc3 *dwc)
> > return -ENOMEM;
> > }
> >
> > + if (IS_ENABLED(CONFIG_OF) && dwc->dev->of_node)
> > + of_dma_configure(&xhci->dev, dwc->dev->of_node);
>
> okay, so we have a long discussion about this going on. You can catch up with it
> starting here:
>
> http://marc.info/?i=1461612094-30939-1-git-send-email-grygorii.strashko@xxxxxx
>
> At least for now, this patch will be applied. We need to have a better solution for this,
> one that helps not only DT platforms.
>

Thanks for information.

> --
> balbi