Hi,
On 02-06-16 20:16, Bin Liu wrote:
Hi,
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?
I guess not, but if there are 2 then with my patch we are of no worse
then today, we will then pick the first otg controller. Whereas
of_usb_get_dr_mode_by_phy currently is broken even on setups with
a shared phy dt-node and only 1 otg controller, which are quite
common.
I believe it is unlikely that there will be more then 1 otg controller,
so I believe that we should not worry about this until we actually
hit this problem.
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
OTG."
So it is not mandatory to define dr_mode in DT, then you wouldn't be
able to find the controller in such case.
If no controller is found then of_usb_get_dr_mode_by_phy will return
USB_DR_MODE_UNKNOWN, just like it does today for controller nodes which
do not set dr_mode.
So in this case my patch does not change anything.
Regards,
Hans
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