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authorHeiko Stuebner <heiko@sntech.de>2015-11-19 22:22:26 +0100
committerKishon Vijay Abraham I <kishon@ti.com>2015-12-20 10:51:38 +0100
commitb74fe7c7617fd267c10d53e525984df81a5f317f (patch)
tree12e5572ae0f7e55151c04b2d23e8e2f82b75f997 /Documentation/usb/usb-help.txt
parentphy: rockchip-usb: add compatible values for rk3066a and rk3188 (diff)
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phy: rockchip-usb: expose the phy-internal PLLs
The USB phys on Rockchip SoCs contain their own internal PLLs to create the 480MHz needed. Additionally this PLL output is also fed back into the core clock-controller as possible source for clocks like the GPU or others. Until now this was modelled incorrectly with a "virtual" factor clock in the clock controller. The one big caveat is that if we turn off the usb phy via the siddq signal, all analog components get turned off, including the PLLs. It is therefore possible that a source clock gets disabled without the clock driver ever knowing, possibly making the system hang. Therefore register the phy-plls as real clocks that the clock driver can then reference again normally, making the clock hirarchy finally reflect the actual hardware. The phy-ops get converted to simply turning that new clock on and off which in turn controls the siddq signal of the phy. Through this the driver gains handling for platform-specific data, to handle the phy->clock name association. Signed-off-by: Heiko Stuebner <heiko@sntech.de> Reviewed-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
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