Re: [RFC PATCH v2 1/3] dt-bindings: usb: mtk-xhci: add compatible for mt8195

[Chunfeng Yun <chunfeng.yun@mediatek.com>]

On Wed, 2021-02-03 at 11:31 +0100, Greg Kroah-Hartman wrote:
> On Wed, Feb 03, 2021 at 06:26:40PM +0800, Chunfeng Yun wrote:
> > There are 4 USB controllers on MT8195, the controllers (IP1~IP3,
> > exclude IP0) have a wrong default SOF/ITP interval which is
> > calculated from the frame counter clock 24Mhz by default, but
> > in fact, the frame counter clock is 48Mhz, so we should set
> > the accurate interval according to 48Mhz. Here add a new compatible
> > for MT8195, it's also supported in driver. But the first controller
> > (IP0) has no such issue, we prefer to use generic compatible,
> > e.g. mt8192's compatible.
> > 
> > Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
> > ---
> > v2: no changes
> 
> Note, I do not apply patches with "RFC" as obviously you do not think
> they are worthy of being applied.  I don't see what you are asking to be
> done with this set of patches, please explain?
The DTS patch [2/3] in the series will cause merge conflict, due to the
dependent patches are not upstreamed.

Another problem is that I wander to know whether the compatible usage as
following is allowed:

arch/arm64/boot/dts/mediatek/mt8195.dtsi

   usb@11200000 {  // ip0
        compatible = "mediatek,mt8192-xhci",  // here use mt8192's
compatible, avoid changing SOF/ITP interval for ip0, because it's
default value is ok."mediatek,mt8192-xhci" is not supported in driver,
so finally will use generic copatible "mediatek,mtk-xhci".

                     "mediatek,mtk-xhci";
        ....
    };

   usb@11290000 {  // ip1
        compatible = "mediatek,mt8195-xhci",  // here use mt8195's
compatible, used to change SOF/ITP interval, due the the wrong default
value.
                     "mediatek,mtk-xhci";
   };

   usb@112a0000 {  // ip2
        compatible = "mediatek,mt8195-xhci",  // same as ip1
                     "mediatek,mtk-xhci";
    };

Thank you

> 
> thanks,
> 
> greg k-h