Re: [PATCH 2/2] phy: rockchip-emmc: should be a child device of the GRF

From: Heiko Stübner
Date: Thu Mar 24 2016 - 11:35:34 EST


Hi Shawn,

Am Donnerstag, 24. MÃrz 2016, 21:36:05 schrieb Shawn Lin:
> å 2016/3/24 21:22, Heiko Stuebner åé:
> > The emmc-phy is fully enclosed in the general register files (GRF).
> > Therefore as seen from the device-tree it shouldn't be a separate
> > platform-
> > device but instead a sub-device of the GRF - using the simply-mfd
> > mechanism.
> >
> > The driver entered the kernel in the current merge-window, so we can still
> > adapt the binding without needing a fallback, as the binding hasn't been
> > released with a full kernel yet.
> >
> > Signed-off-by: Heiko Stuebner <heiko@xxxxxxxxx>
> > ---
> > Hi Shawn, Kishon,
> >
> > I didn't see this new phy driver until now, so I'd really like to get
> > this sorted before the old binding solidifies :-).
> >
> > I'll convert the usbphy as well, but that has to have the fallback for
> > the old binding, so is not as urgent as these two.
> >
> > As mentioned in the patch description above, this is meant as a fixup for
> > kernel 4.6.
> >
> >
> > One thing I noticed, the emmc phy is occupying the range 0xf780-0xf7a0,
> > so shouldn't the reg property reflect that, like
> >
> > reg = <0xf780 0x20>;
> >
> > to stay with common conventions?
>
> yes, and I had a fix[0] for it waiting for Kishon's reviewing.

please try to always include both me and the linux-rockchip list for Rockchip
specific changes in the future :-) .

In any case, I do think going with a reg property might be more standard
conformant, once it is under the GRF. Of course only for sub-devices that
actually occupy a real block inside the GRF like your emmc phy or the new
usbphy blocks.

So I guess the dts should probably look like:


grf: syscon@ff770000 {
compatible = "rockchip,rk3399-grf", "syscon", "simple-mfd";
#address-cells = <1>;
#size-cells = <1>;

emmcphy: phy@f780 {
compatible = "rockchip,rk3399-emmc-phy";
reg = <0xf780 0x20>;
#phy-cells = <0>;
};
};


> [0]:
> http://lkml.org/lkml/2016/3/8/114
>
> > .../devicetree/bindings/phy/rockchip-emmc-phy.txt | 19
> > ++++++++++++------- drivers/phy/phy-rockchip-emmc.c
> > | 5 ++++-
> > 2 files changed, 16 insertions(+), 8 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
> > b/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt index
> > 61916f1..d711259 100644
> > --- a/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
> > +++ b/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
> > @@ -3,17 +3,22 @@ Rockchip EMMC PHY
> >
> > Required properties:
> > - compatible: rockchip,rk3399-emmc-phy
> >
> > - - rockchip,grf : phandle to the syscon managing the "general
> > - register files"
> >
> > - #phy-cells: must be 0
> > - reg: PHY configure reg address offset in "general
> >
> > register files"
> >
> > Example:
> > -emmcphy: phy {
> > - compatible = "rockchip,rk3399-emmc-phy";
> > - rockchip,grf = <&grf>;
> > - reg = <0xf780>;
> > - #phy-cells = <0>;
> > +
> > +grf: syscon@ff770000 {
> > + compatible = "rockchip,rk3399-grf", "syscon", "simple-mfd";
> > +
> > +...
> > +
> > + emmcphy: phy@f780 {
> > + compatible = "rockchip,rk3399-emmc-phy";
> > + rockchip,grf = <&grf>;

I just saw I missed to remove that now obsolete rockchip,grf property.


> > + reg = <0xf780>;
> > + #phy-cells = <0>;
> > + };
> >
> > };
> >
> > diff --git a/drivers/phy/phy-rockchip-emmc.c
> > b/drivers/phy/phy-rockchip-emmc.c index 887b4c2..6ebcf3e 100644
> > --- a/drivers/phy/phy-rockchip-emmc.c
> > +++ b/drivers/phy/phy-rockchip-emmc.c
> > @@ -176,7 +176,10 @@ static int rockchip_emmc_phy_probe(struct
> > platform_device *pdev)>
> > struct regmap *grf;
> > unsigned int reg_offset;
> >
> > - grf = syscon_regmap_lookup_by_phandle(dev->of_node, "rockchip,grf");
> > + if (!dev->parent || !dev->parent->of_node)
> > + return -ENODEV;
> > +
> > + grf = syscon_node_to_regmap(dev->parent->of_node);
> >
> > if (IS_ERR(grf)) {
> >
> > dev_err(dev, "Missing rockchip,grf property\n");
> > return PTR_ERR(grf);