Hi Rob, > -----Original Message----- > From: Rob Herring > Sent: Wednesday, July 5, 2017 11:16 PM > > On Wed, Jun 28, 2017 at 03:28:35PM +0900, Yoshihiro Shimoda wrote: > > R-Car USB 2.0 controller can change the clock source from an oscillator > > to an external clock via a register. So, this patch adds support > > the clock source selector as a clock driver. > > > > Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx> > > --- > > This patch is based on the renesas-drivers.git / > > renesas-drivers-2017-06-27-v4.12-rc7 tag. > > > > Changes from v1: > > - Change this driver as a clock driver from a generic phy driver. > > https://patchwork.kernel.org/patch/9788697/ > > - Remove "RFC" tag. > > > > .../bindings/clock/renesas,rcar-usb2-clock-sel.txt | 54 ++++++ > > drivers/clk/renesas/Kconfig | 5 + > > drivers/clk/renesas/Makefile | 1 + > > drivers/clk/renesas/rcar-usb2-clock-sel.c | 205 +++++++++++++++++++++ > > 4 files changed, 265 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/clock/renesas,rcar-usb2-clock-sel.txt > > create mode 100644 drivers/clk/renesas/rcar-usb2-clock-sel.c > > > > diff --git a/Documentation/devicetree/bindings/clock/renesas,rcar-usb2-clock-sel.txt > b/Documentation/devicetree/bindings/clock/renesas,rcar-usb2-clock-sel.txt > > new file mode 100644 > > index 0000000..75ccafc > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/clock/renesas,rcar-usb2-clock-sel.txt > > @@ -0,0 +1,54 @@ > > +* Renesas R-Car USB 2.0 clock selector > > + > > +This file provides information on what the device node for the R-Car USB 2.0 > > +clock selector. > > + > > +If you connect an external clock to the USB_EXTAL pin only, you should set > > +the clock rate to "usb_extal" node only. > > +If you connect an oscillator to both the USB_XTAL and USB_EXTAL, this module > > +is not needed because this is default setting. (Of course, you can set the > > +clock rates to both "usb_extal" and "usb_xtal" nodes. > > + > > +Case 1: An external clock connects to R-Car SoC > > + +----------+ +--- R-Car ---------------------+ > > + |External |---|USB_EXTAL ---> all usb channels| > > + |clock | |USB_XTAL | > > + +----------+ +-------------------------------+ > > +In this case, we need this driver with "usb_extal" clock. > > + > > +Case 2: An oscillator connects to R-Car SoC > > + +----------+ +--- R-Car ---------------------+ > > + |Oscillator|---|USB_EXTAL -+-> all usb channels| > > + | |---|USB_XTAL --+ | > > + +----------+ +-------------------------------+ > > +In this case, we don't need this selector. > > + > > +Required properties: > > +- compatible: "renesas,r8a7795-rcar-usb2-clock-sel" if the device is a part of > > + an R8A7795 SoC. > > + "renesas,r8a7796-rcar-usb2-clock-sel" if the device if a part of > > + an R8A7796 SoC. > > + "renesas,rcar-gen3-usb2-clock-sel" for a generic R-Car Gen3 > > + compatible device. > > + > > + When compatible with the generic version, nodes must list the > > + SoC-specific version corresponding to the platform first > > + followed by the generic version. > > + > > +- reg: offset and length of the USB 2.0 clock selector register block. > > +- clocks: A list of phandles and specifier pairs. > > +- clock-names: Name of the clocks. > > + - The functional clock must be "ehci_ohci" > > + - The USB_EXTAL clock pin must be "usb_extal" > > + - The USB_XTAL clock pin must be "usb_xtal" > > +- #clock-cells: Must be 0 > > + > > +Exxample (R-Car H3): > > + > > + usb2_clksel: clock-controller@e6590630 { > > + compatible = "renesas,r8a77950-rcar-usb2-clock-sel", > > + "renesas,rcar-gen3-usb2-clock-sel"; > > + reg = <0 0xe6590630 0 0x02>; > > + clocks = <&cpg CPG_MOD 703>, <&usb_extal>, <&usb_xtal>; > > + clock-names = "ehci_ohci", "usb_extal", "usb_xtal"; > > Missing #clock-cells Oops, I will fix it. > With that, for the binding: > > Acked-by: Rob Herring <robh@xxxxxxxxxx> Thank you for your Acked-by! Best regards, Yoshihiro Shimoda > Rob
