[PATCH 0/8] phy: rockchip-usb: correct pll handling and usb-uart

Heiko Stuebner heiko at sntech.de
Wed Nov 4 13:44:06 PST 2015

Patches 1-7 fix a long-standing issue with the clock-tree of Rockchip SoCs
namely our ignorance of the usbphy-internal pll that creates the needed
480MHz but is also a supply-clock back to the core clock-controller in
Rockchip SoCs.

Till now that was worked around using a virtual clock in the cru itself,
but that is of course ignorant of other parts then disabling the phy
behind the cru's back, thus breaking potential users of these clocks.

Patch 8, while not associated with the new pll handling, also builds
on the groundwork introduced there and adds support for the function
repurposing one of the phys as passthrough for uart-data. This enables
attaching a ttl converter to the D+ and D- pins of an usb cable to
receive uart data this way, when it is not really possible to attach
a regular serial console to a board.

One point of critique in my first iteration [0] of this was, that
due to when the reconfiguration happens we may miss parts of the logs
when earlycon is enabled. So far early_initcall gets used as the
unflattened devicetree is necessary to set this up. Doing this for
example in the early_param directly would require parsing the flattened
devicetree to get needed nodes and properties.

I still maintain that if you're working on anything before smp-bringup
you should use a real dev-board instead or try to solder uart cables
on hopefully available test-points :-) .

In any case, if patch 8 causes to much headache, it could be dropped
to not hinder the earlier 7 patches.

[0] http://comments.gmane.org/gmane.linux.ports.arm.rockchip/715

Heiko Stuebner (8):
  phy: rockchip-usb: fix clock get-put mismatch
  phy: rockchip-usb: introduce a common data-struct for the device
  phy: rockchip-usb: move per-phy init into a separate function
  phy: rockchip-usb: expose the phy-internal PLLs
  clk: rockchip: fix usbphy-related clocks
  ARM: dts: rockchip: add clock-cells for usb phy nodes
  ARM: dts: rockchip: assign usbphy480m_src to the new usbphy pll on
  phy: rockchip-usb: add handler for usb-uart functionality

 .../devicetree/bindings/phy/rockchip-usb-phy.txt   |   6 +-
 Documentation/kernel-parameters.txt                |   6 +
 arch/arm/boot/dts/rk3066a.dtsi                     |   2 +
 arch/arm/boot/dts/rk3188.dtsi                      |   2 +
 arch/arm/boot/dts/rk3288-veyron.dtsi               |   2 +-
 arch/arm/boot/dts/rk3288.dtsi                      |   3 +
 drivers/clk/rockchip/clk-rk3188.c                  |  11 +-
 drivers/clk/rockchip/clk-rk3288.c                  |  16 +-
 drivers/phy/phy-rockchip-usb.c                     | 451 ++++++++++++++++++---
 9 files changed, 417 insertions(+), 82 deletions(-)


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