On Thu, Jun 15, 2017 at 08:34:22PM +0900, Yoshihiro Shimoda wrote: > USB 2.0 PHY of R-Car Gen3 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 generic PHY driver. > > Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx> > --- > This patch is based on the latest linux-phy.git / next branch > (commit id = 787f24543c4a599e5d9d311a3fce839ce87bbff0) > > I'm not sure this driver ss OK or not as a generic phy driver. > So, I send this patch as RFC. > > .../bindings/phy/rcar-gen3-phy-usb2-clksel.txt | 58 +++++++++ > drivers/phy/renesas/Kconfig | 8 ++ > drivers/phy/renesas/Makefile | 1 + > drivers/phy/renesas/phy-rcar-gen3-usb2-clksel.c | 129 +++++++++++++++++++++ > 4 files changed, 196 insertions(+) > create mode 100644 Documentation/devicetree/bindings/phy/rcar-gen3-phy-usb2-clksel.txt > create mode 100644 drivers/phy/renesas/phy-rcar-gen3-usb2-clksel.c > > diff --git a/Documentation/devicetree/bindings/phy/rcar-gen3-phy-usb2-clksel.txt b/Documentation/devicetree/bindings/phy/rcar-gen3-phy-usb2-clksel.txt > new file mode 100644 > index 0000000..71b2f1b > --- /dev/null > +++ b/Documentation/devicetree/bindings/phy/rcar-gen3-phy-usb2-clksel.txt > @@ -0,0 +1,58 @@ > +* Renesas R-Car generation 3 USB 2.0 clock selector PHY > + > +This file provides information on what the device node for the R-Car generation > +3 USB 2.0 clock selector PHY contains. Is this a phy or just a clock selector and nothing else? It sounds more like the latter and you should use the clock binding. Whether this is a phy driver in the kernel is a separate question really. > + > +If you connect an external clock to the USB_EXTAL pin, you can use the > +"renesas,usb_extal_only" property for it. > +If you connect an oscillator to both the USB_XTAL and USB_EXTAL, this module > +is not needed because this is default setting. > + > +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-only" property. > + > +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.
