Re: [PATCH 8/9 v2] usb: usb251xb: Add max power/current dts property support

From: Rob Herring
Date: Wed Sep 20 2017 - 16:57:20 EST


On Sat, Sep 16, 2017 at 01:42:19PM +0300, Serge Semin wrote:
> This parameters may be varied in accordance with hardware specifics.
> So lets add the corresponding settings to the usb251x driver dts
> specification.
>
> Signed-off-by: Serge Semin <fancer.lancer@xxxxxxxxx>
> ---
> Documentation/devicetree/bindings/usb/usb251xb.txt | 6 ++++++
> drivers/usb/misc/usb251xb.c | 20 ++++++++++++++++----
> 2 files changed, 22 insertions(+), 4 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/usb/usb251xb.txt b/Documentation/devicetree/bindings/usb/usb251xb.txt
> index 3d84626d3..dd59a32e7 100644
> --- a/Documentation/devicetree/bindings/usb/usb251xb.txt
> +++ b/Documentation/devicetree/bindings/usb/usb251xb.txt
> @@ -44,6 +44,12 @@ Optional properties :
> device connected.
> - sp-disabled-ports : Specifies the ports which will be self-power disabled
> - bp-disabled-ports : Specifies the ports which will be bus-power disabled
> + - sp-max-{power,current} : Indicates the power/current consumed by hub from
> + an upstream port (VBUS) when operation as a self-powered hub. The value
> + is given in mA in a 0 - 100 range (default is 1mA).
> + - bp-max-{power,current} : Indicates the power/current consumed by hub from
> + an upstream port (VBUS) when operation as a bus-powered hub. The value
> + is given in mA in a 0 - 510 range (default is 100mA).

These need units as defined in property-units.txt.

Why do you need power and current? Can't you calculate power?

> - power-on-time-ms : Specifies the time it takes from the time the host
> initiates the power-on sequence to a port until the port has adequate
> power. The value is given in ms in a 0 - 510 range (default is 100ms).