Amelie DELAUNAY <amelie.delaunay@xxxxxx> 于2020年11月5日周四 下午7:36写道: > > On 11/4/20 10:08 PM, Rob Herring wrote: > > On Fri, Oct 30, 2020 at 04:27:14PM +0100, Amelie DELAUNAY wrote: > >> > >> > >> On 10/30/20 3:29 PM, Rob Herring wrote: > >>> On Thu, Oct 29, 2020 at 11:49 AM Amelie DELAUNAY <amelie.delaunay@xxxxxx> wrote: > >>>> > >>>> > >>>> > >>>> On 10/29/20 4:40 PM, Rob Herring wrote: > >>>>> On Thu, Oct 29, 2020 at 10:58:03AM +0100, Amelie Delaunay wrote: > >>>>>> Power operation mode may depends on hardware design, so, add the optional > >>>>>> property power-opmode for usb-c connector to select the power operation > >>>>>> mode capability. > >>>>>> > >>>>>> Signed-off-by: Amelie Delaunay <amelie.delaunay@xxxxxx> > >>>>>> --- > >>>>>> .../bindings/connector/usb-connector.yaml | 18 ++++++++++++++++++ > >>>>>> 1 file changed, 18 insertions(+) > >>>>>> > >>>>>> diff --git a/Documentation/devicetree/bindings/connector/usb-connector.yaml b/Documentation/devicetree/bindings/connector/usb-connector.yaml > >>>>>> index 728f82db073d..200d19c60fd5 100644 > >>>>>> --- a/Documentation/devicetree/bindings/connector/usb-connector.yaml > >>>>>> +++ b/Documentation/devicetree/bindings/connector/usb-connector.yaml > >>>>>> @@ -93,6 +93,24 @@ properties: > >>>>>> - device > >>>>>> - dual > >>>>>> > >>>>>> + power-opmode: > >>>>> > >>>>> I've acked this version: > >>>>> > >>>>> https://lore.kernel.org/r/20201020093627.256885-2-badhri@xxxxxxxxxx > >>>>> > >>>> > >>>> frs is used for Fast Role Swap defined in USB PD spec. > >>>> I understand it allows to get the same information but I'm wondering why > >>>> the property name is limited to -frs- in this case. What about a > >>>> non-power delivery USB-C connector ? > >>> > >>> I've got no idea. The folks that know USB-C and PD details need to get > >>> together and work all this out. To me, it looks like the same thing... > >>> > >> > >> It looks but... > >> > >> The purpose of power-opmode property is to configure the USB-C controllers, > >> especially the non-PD USB-C controllers to determine the power operation > >> mode that the Type C connector will support and will advertise through CC > >> pins when it has no power delivery support, whatever the power role: Sink, > >> Source or Dual > >> The management of the property is the same that data-role and power-role > >> properties, and done by USB Type-C Connector Class. > >> > >> new-source-frs-typec-current specifies initial current capability of the new > >> source when vSafe5V is applied during PD3.0 Fast Role Swap. So here, this > >> property is not applied at usb-c controller configuration level, but during > >> PD Fast Role Swap, so when the Sink become the Source. > >> Moreover, the related driver code says FRS can only be supported by DRP > >> ports. So new-source-frs-typec-current property, in addition to being > >> specific to PD, is also dedicated to DRP usb-c controller. > >> The property is managed by Type-C Port Controller Manager for PD. > > > > But it's the same set of possible values, right? So we can align the > > values at least. > > > > USB Power Delivery FRS values are defined in > include/dt-bindings/usb/pd.h I think this can be changed if both can be aligned. >to fit with drivers/usb/typec/tcpm/tcpm.c > frs_typec_current enum. > > USB-C power operation mode values are defined in > include/linux/usb/typec.h with typec_pwr_opmode enum and matching with > string values of typec_pwr_opmodes tab. > > USB PD requires USB-C. > USB-C doesn't requires USB PD. > > drivers/usb/typec/tcpm/tcpm.c already used typec_pwr_opmode values. > > USB PD specification Table 6-14 Fixed Supply PDO says: > Fast Role Swap required USB Type-C Current (see also [USB Type-C 2.0]): > Value | Description > 00b | Fast Swap not supported (default) > 01b | Default USB Power > 10b | 1.5A @ 5V > 11b | 3.0A @ 5V This is the value in PDO of sink, the FRS property value(or after translated) actually is used to compare with above value. So I think both properties can share the same "value", maybe string like below 10 static const char * const typec_pwr_opmodes[] = { 11 [TYPEC_PWR_MODE_USB] = "default", 12 [TYPEC_PWR_MODE_1_5A] = "1.5A", 13 [TYPEC_PWR_MODE_3_0A] = "3.0A", > > Note the *see also USB Type-C 2.0*. > > USB Type-C specification 4.6.2.1 USB Type-C Current says: > The USB Type-C connector uses CC pins for configuration including an > ability for a Source to advertise to its port partner (Sink) the amount > of current it shall supply: > • Default is the as-configured for high-power operation current value as > defined by the USB Specification (500 mA for USB 2.0 ports; 900 mA or > 1,500 mA for USB 3.2 ports in single-lane or dual-lane operation, > respectively) > • 1.5 A > • 3.0 A > > > Can we align the names in some way? power-opmode and frs-source-opmode > > or ?? how about typec-power-opmode and frs-new-source-opmode > > > > I let USB PD specialists answer. > > *frs* property fits with USB PD specification, so with USB PD protocol. > *power-opmode fits with USB Type-C specification, so with USB-C hardware > support. > > > Are these 2 properties mutually exclusive? I think yes. thanks Li Jun >> If so, that should be > > captured. > > FRS is specific to products with Power Delivery Support. > > power-opmode is dedicated to products with USB-C connector support. > > Regards, > Amelie