Re: [RESEND PATCH v2] arm64: dts: rockchip: add u2phy clock for ehci and ohci of rk3399
From: Heiko Stuebner
Date: Tue Dec 27 2016 - 12:04:38 EST
Am Mittwoch, 21. Dezember 2016, 18:41:05 CET schrieb Xing Zheng:
> From: William wu <wulf@xxxxxxxxxxxxxx>
>
> We found that the suspend process was blocked when it run into
> ehci/ohci module due to clk-480m of usb2-phy was disabled.
>
> The root cause is that usb2-phy suspended earlier than ehci/ohci
> (usb2-phy will be auto suspended if no devices plug-in). and the
> clk-480m provided by it was disabled if no module used. However,
> some suspend process related ehci/ohci are base on this clock,
> so we should refer it into ehci/ohci driver to prevent this case.
>
> The u2phy clock flow like this:
> ===
> u2phy ________________
>
> | | |-----> UTMI_CLK ---------> | EHCI |
>
> OSC_24M ---|---> PHY_PLL----|----|
>
> |________^_______| |-----> 480M_CLK ---|G|---> |
> |USBPHY_480M_SRC| ----> USBPHY_480M for SoC
> GRF
> ===
>
> Signed-off-by: William wu <wulf@xxxxxxxxxxxxxx>
> Signed-off-by: Xing Zheng <zhengxing@xxxxxxxxxxxxxx>
applied for 4.11 with Doug's Review-tag
Thanks
Heiko