[PATCH 1/4] USB: Fix of_usb_get_dr_mode_by_phy with a shared phy block
b-liu at ti.com
Thu Jun 2 11:16:48 PDT 2016
On Thu, Jun 02, 2016 at 07:31:03PM +0200, Hans de Goede wrote:
> Some SoCs have a single phy-hw-block with multiple phys, this is
> modelled by a single phy dts node, so we end up with multiple
> controller nodes with a phys property pointing to the phy-node
> of the otg-phy.
> Only one of these controllers typically is an otg controller, yet we
Is it guaranteed that only one of them will be otg?
> were checking the first controller who uses a phy from the block and
> then end up looking for a dr_mode property in e.g. the ehci controller.
> Instead of looking for nodes with a phy property, look for nodes
> with a dr_mode property, so that we actually access the dr_mode property
> in a node which has it.
Quote from Documentation/devicetree/bindings/usb/generic.txt:
"- dr_mode: ...
In case this attribute isn't
passed via DT, USB DRD controllers should default to
So it is not mandatory to define dr_mode in DT, then you wouldn't be
able to find the controller in such case.
More information about the linux-arm-kernel