On Thu, Sep 21, 2017 at 11:26:04AM -0500, Rob Herring <robh@xxxxxxxxxx> wrote: > On Wed, Sep 20, 2017 at 4:27 PM, Serge Semin <fancer.lancer@xxxxxxxxx> wrote: > > On Wed, Sep 20, 2017 at 03:52:55PM -0500, Rob Herring <robh@xxxxxxxxxx> wrote: > >> 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. > >> > > > > Ok. > > > >> Why do you need power and current? Can't you calculate power? > >> > > > > These are different parameters of the device. They got different configuration > > registers and descriptions: > > max_power* - ... This value also includes the power consumption of a > > permanently attached peripheral if the hub is configured as a compound > > device, and the embedded peripheral reports 0mA in its descriptors. > > max_current* - ... This value does NOT include the power consumption of a > > permanently attached peripheral if the hub is configured as a compound > > device. > > Then the names here should somehow reflect the above. Perhaps > "composite-current" and "hub-current" or something like that. > I left the naming in accordance with the device datasheet. I thought it would be better since the driver user would still need to consult with the device documentation to properly set them. I don't really get how the difference is reflected with the naming declared there though. So what naming would you prefer then? Might be something like: {sp,bp}-max-total-current - for so named {sp,bp}-max-power, since it includes all the permanently attached peripherals. {sp,bp}-max-removable-current - for so named {sp,bp}-max-current, since it doesn't include the permanently attached peripherals. Or is it better to leave it in compliance with the documentation naming? > > > > Additionally as you can see, they both are measured in "mA", so it isn't > > a real physical power. > > Well, I can't because there's no units. > What this line means then? - sp-max-{power,current} : ... The value is given in mA in a 0 - 100 range (default is 1mA). - bp-max-{power,current} : ... The value is given in mA in a 0 - 510 range (default is 100mA). Maybe I don't know something and the description line should state the units somehow clearer? > Rob -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html