RE: [PATCH] usb: dwc3: imx8mp: detect dwc3 core node via compatible string

[Jun Li <jun.li@nxp.com>]

Hi,

> -----Original Message-----
> From: Felipe Balbi <balbi@kernel.org>
> Sent: Friday, April 30, 2021 4:24 PM
> To: Jun Li <jun.li@nxp.com>; gregkh@linuxfoundation.org
> Cc: shawnguo@kernel.org; dl-linux-imx <linux-imx@nxp.com>;
> thunder.leizhen@huawei.com; linux-usb@vger.kernel.org
> Subject: Re: [PATCH] usb: dwc3: imx8mp: detect dwc3 core node via compatible
> string
> 
> Li Jun <jun.li@nxp.com> writes:
> 
> > New schema of usb controller DT-node should be named with prefix
> > "^usb(@.*)?", dt changed the node name, but missed counter part change
> > in driver, fix it by switching to use compatible string as the dwc3
> > core compatible string keeps "snps,dwc3" in all dt.
> >
> > Fixes: d1689cd3c0f4 ("arm64: dts: imx8mp: Use the correct name for
> > child node "snps, dwc3"")
> > Signed-off-by: Li Jun <jun.li@nxp.com>
> 
> 
> Nice fix :-) It may break down if we have two dwc3 nodes as child of a single
> parent, but I guess that's very unlikely anyway.
> 
> Acked-by: Felipe Balbi <balbi@kernel.org>
> 
> That being said, why do need to keep a pointer to the child? I had a quick
> look at the driver and it doesn't seem like the pointer is necessary at all.

I need keep the child pointer(dwc3 core platform device) to find the dwc3 core
instance struct(struct dwc3), the wakeup setting need check the dwc3 core's
current_dr_role and do runtime resume based on the child's dev. 

Thanks
Li Jun 
> 
> --
> balbi