| Message ID | 20170928130730.8747-2-a.hajda@samsung.com (mailing list archive) |
|---|---|
| State | New, archived |
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On Thu, Sep 28, 2017 at 03:07:27PM +0200, Andrzej Hajda wrote: > These bindings allows to describe most known standard USB connectors > and it should be possible to extend it if necessary. > USB connectors, beside USB can be used to route other protocols, > for example UART, Audio, MHL. In such case every device passing data > through the connector should have appropriate graph bindings. Yay! > Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> > --- > There are few things for discussion (IMO): > 1. vendor specific connectors, I have added them here, but maybe better is > to place them in separate files. I'd worry about the standard connectors first, but probably good to have an idea of how vendor connectors need to be extended. > 2. physical connector description - I have split it to three properties: > type(a,b,ab,c), max-mode(ls,fs,hs,ss,ss+), size(mini,micro,powered). > This tripled is able to describe all USB-standard connectors, but there > are also impossible combinations, for example(c, *, micro). Maybe better > would be to just enumerate all possible connectors in include file. We did "type" for hdmi-connector, but I think I'd really prefer compatible be used to distinguish as least where it may matter to s/w. In the HDMI case, they all are pretty much the same, just different physical size. > 3. Numbering of port/remote nodes, currently only 0 is assigned for Interface > Controller. Maybe other functions should be also assigned: > HS, SS, CC, SBU, ... whatever. Maybe functions should be described > as an additional property of remote node? child of the controller is also an option. There's already prec > ... > > Regards > Andrzej > --- > .../bindings/connector/usb-connector.txt | 49 ++++++++++++++++++++++ > 1 file changed, 49 insertions(+) > create mode 100644 Documentation/devicetree/bindings/connector/usb-connector.txt > > diff --git a/Documentation/devicetree/bindings/connector/usb-connector.txt b/Documentation/devicetree/bindings/connector/usb-connector.txt > new file mode 100644 > index 000000000000..f3a4e85122d5 > --- /dev/null > +++ b/Documentation/devicetree/bindings/connector/usb-connector.txt > @@ -0,0 +1,49 @@ > +USB Connector > +============= > + > +Required properties: > +- compatible: "usb-connector" > + connectors with vendor specific extensions can add one of additional > + compatibles: > + "samsung,usb-connector-11pin": 11-pin Samsung micro-USB connector > +- type: the USB connector type: "a", "b", "ab", "c" > +- max-mode: max USB speed mode supported by the connector: > + "ls", "fs", "hs", "ss", "ss+" Do we really see cases where the connector is slower than the controller? Plus things like "ls" with an type A connector are not valid. > + > +Optional properties: > +- label: a symbolic name for the connector > +- size: size of the connector, should be specified in case of > + non-standard USB connectors: "mini", "micro", "powered" What does powered mean? This is really "type" if you compare to HDMI. > + > +Required nodes: > +- any data bus to the connector should be modeled using the > + OF graph bindings specified in bindings/graph.txt. > + There should be exactly one port with at least one endpoint to > + different device nodes. The first endpoint (reg = <0>) should > + point to USB Interface Controller. > + > +Example > +------- > + > +musb_con: connector { > + compatible = "samsung,usb-connector-11pin", "usb-connector"; > + label = "usb"; > + type = "b"; > + size = "micro"; > + max-mode = "hs"; These all are implied by "samsung,usb-connector-11pin". > + > + port { > + #address-cells = <1>; > + #size-cells = <0>; > + > + musb_con_usb_in: endpoint@0 { > + reg = <0>; > + remote-endpoint = <&muic_usb_out>; > + }; > + > + musb_con_mhl_in: endpoint@1 { > + reg = <1>; > + remote-endpoint = <&mhl_out>; > + }; I think this should be 2 ports, not 2 endpoints. Think of ports as different data streams and endpoints are either the same data stream muxed or fanned out depending on direction. Now for Type-C, 1 port for USB and alternate modes is probably correct. Rob
Hi Rob, Thanks for review. On 06.10.2017 01:12, Rob Herring wrote: > On Thu, Sep 28, 2017 at 03:07:27PM +0200, Andrzej Hajda wrote: >> These bindings allows to describe most known standard USB connectors >> and it should be possible to extend it if necessary. >> USB connectors, beside USB can be used to route other protocols, >> for example UART, Audio, MHL. In such case every device passing data >> through the connector should have appropriate graph bindings. > Yay! > >> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> >> --- >> There are few things for discussion (IMO): >> 1. vendor specific connectors, I have added them here, but maybe better is >> to place them in separate files. > I'd worry about the standard connectors first, but probably good to have > an idea of how vendor connectors need to be extended. > >> 2. physical connector description - I have split it to three properties: >> type(a,b,ab,c), max-mode(ls,fs,hs,ss,ss+), size(mini,micro,powered). >> This tripled is able to describe all USB-standard connectors, but there >> are also impossible combinations, for example(c, *, micro). Maybe better >> would be to just enumerate all possible connectors in include file. > We did "type" for hdmi-connector, but I think I'd really prefer > compatible be used to distinguish as least where it may matter to s/w. > In the HDMI case, they all are pretty much the same, just different > physical size. I guess that from S/W point of view only matters: - which IP is connected to which part of the connector, and this can be handled by port node(s), - Type: A, B, C - probably maximal supported speed of the connector - for example SS+ connectors have the same wires but different electrical characteristics than SS as I understand, With this in mind maybe we can drop 'type' and introduce following compatibles: - usb-a-connector, - usb-b-connector, - usb-c-connector. Encoding other properties in compatible would explode their number, so I would prefer to avoid it. I would leave other props: max-speed: hs, ss, ss+, (optional)size: micro, mini I would drop also unpopular/obsolete variants: type-ab, powered, they can be added later if necessary. Just for reference, list of connectors defined by USB (>= 2) specifications: 1. USB 2.0 (with later amendments): - Standard-A plug and receptacle - Standard-B plug and receptacle - Mini-B plug and receptacle - Micro-B plug and receptacle - Micro-AB receptacle - Micro-A plug 2. USB 3.0: - USB 3.0 Standard-A plug and receptacle - USB 3.0 Standard-B plug and receptacle - USB 3.0 Powered-B plug and receptacle - USB 3.0 Micro-B plug and receptacle - USB 3.0 Micro-A plug - USB 3.0 Micro-AB receptacle 3. USB 3.1: - Enhanced SuperSpeed Standard-A plug and receptacle - Enhanced SuperSpeed Standard-B plug and receptacle - Enhanced SuperSpeed Micro-B plug and receptacle - Enhanced SuperSpeed Micro-A plug - Enhanced SuperSpeed Micro-AB receptacle 4. USB-C (release 1.3): - USB Full-Featured Type-C receptacle - USB 2.0 Type-C receptacle - USB Full-Featured Type-C plug - USB 2.0 Type-C plug - USB Type-C Power-Only plug >> 3. Numbering of port/remote nodes, currently only 0 is assigned for Interface >> Controller. Maybe other functions should be also assigned: >> HS, SS, CC, SBU, ... whatever. Maybe functions should be described >> as an additional property of remote node? > child of the controller is also an option. There's already prec Shall we support both solutions or just make one mandatory? > >> ... >> >> Regards >> Andrzej >> --- >> .../bindings/connector/usb-connector.txt | 49 ++++++++++++++++++++++ >> 1 file changed, 49 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/connector/usb-connector.txt >> >> diff --git a/Documentation/devicetree/bindings/connector/usb-connector.txt b/Documentation/devicetree/bindings/connector/usb-connector.txt >> new file mode 100644 >> index 000000000000..f3a4e85122d5 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/connector/usb-connector.txt >> @@ -0,0 +1,49 @@ >> +USB Connector >> +============= >> + >> +Required properties: >> +- compatible: "usb-connector" >> + connectors with vendor specific extensions can add one of additional >> + compatibles: >> + "samsung,usb-connector-11pin": 11-pin Samsung micro-USB connector >> +- type: the USB connector type: "a", "b", "ab", "c" >> +- max-mode: max USB speed mode supported by the connector: >> + "ls", "fs", "hs", "ss", "ss+" > Do we really see cases where the connector is slower than the > controller? Plus things like "ls" with an type A connector are not > valid. For example Galaxy Note 4 - it has USB3 controller and micro-USB 2.0 connector. > >> + >> +Optional properties: >> +- label: a symbolic name for the connector >> +- size: size of the connector, should be specified in case of >> + non-standard USB connectors: "mini", "micro", "powered" > What does powered mean? It is standard-B connector with additional power pins, as defined in USB3.0 spec, we can drop it as not-popular one. > > This is really "type" if you compare to HDMI. As type is already used, I have to use other word, maybe 'form' would be better. > >> + >> +Required nodes: >> +- any data bus to the connector should be modeled using the >> + OF graph bindings specified in bindings/graph.txt. >> + There should be exactly one port with at least one endpoint to >> + different device nodes. The first endpoint (reg = <0>) should >> + point to USB Interface Controller. >> + >> +Example >> +------- >> + >> +musb_con: connector { >> + compatible = "samsung,usb-connector-11pin", "usb-connector"; >> + label = "usb"; >> + type = "b"; >> + size = "micro"; >> + max-mode = "hs"; > These all are implied by "samsung,usb-connector-11pin". Yes, but "usb-connector" compatible requires/permits it, or am I wrong ? > >> + >> + port { >> + #address-cells = <1>; >> + #size-cells = <0>; >> + >> + musb_con_usb_in: endpoint@0 { >> + reg = <0>; >> + remote-endpoint = <&muic_usb_out>; >> + }; >> + >> + musb_con_mhl_in: endpoint@1 { >> + reg = <1>; >> + remote-endpoint = <&mhl_out>; >> + }; > I think this should be 2 ports, not 2 endpoints. Think of ports as > different data streams and endpoints are either the same data stream > muxed or fanned out depending on direction. Now for Type-C, 1 port for > USB and alternate modes is probably correct. I agree for ports. Regarding type-c, it has separate lines for HS and for SS. HS lines often go to Interface Controller as they can be used to legacy detection methods and alternatively muxed to UART. SS lines go directly to USB3 chip, see for example TPS65982 [1][2]. For me it is an argument against merging SS and HS lines into one port. What do you think? My proposition of port numbering: 0: ID for type-B, CC for type-C 1: HS 2: VBUS - I am not sure if this should be modeled this way, as it is not a data line, 3: SS 4: SBU In case of connector being child node of controller some ports can be omited. [1]: http://www.ti.com/ods/images/SLVSD02C/pg1_slvsd02.gif [2]: http://www.ti.com/product/TPS65982/datasheet Regards Andrzej > > Rob > > >
On Fri, Oct 6, 2017 at 6:10 AM, Andrzej Hajda <a.hajda@samsung.com> wrote: > Hi Rob, > > Thanks for review. > > On 06.10.2017 01:12, Rob Herring wrote: >> On Thu, Sep 28, 2017 at 03:07:27PM +0200, Andrzej Hajda wrote: >>> These bindings allows to describe most known standard USB connectors >>> and it should be possible to extend it if necessary. >>> USB connectors, beside USB can be used to route other protocols, >>> for example UART, Audio, MHL. In such case every device passing data >>> through the connector should have appropriate graph bindings. >> Yay! >> >>> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> >>> --- >>> There are few things for discussion (IMO): >>> 1. vendor specific connectors, I have added them here, but maybe better is >>> to place them in separate files. >> I'd worry about the standard connectors first, but probably good to have >> an idea of how vendor connectors need to be extended. >> >>> 2. physical connector description - I have split it to three properties: >>> type(a,b,ab,c), max-mode(ls,fs,hs,ss,ss+), size(mini,micro,powered). >>> This tripled is able to describe all USB-standard connectors, but there >>> are also impossible combinations, for example(c, *, micro). Maybe better >>> would be to just enumerate all possible connectors in include file. >> We did "type" for hdmi-connector, but I think I'd really prefer >> compatible be used to distinguish as least where it may matter to s/w. >> In the HDMI case, they all are pretty much the same, just different >> physical size. > > I guess that from S/W point of view only matters: > - which IP is connected to which part of the connector, and this can be > handled by port node(s), > - Type: A, B, C > - probably maximal supported speed of the connector - for example SS+ > connectors have the same wires but different electrical characteristics > than SS as I understand, > > With this in mind maybe we can drop 'type' and introduce following > compatibles: > - usb-a-connector, > - usb-b-connector, > - usb-c-connector. > Encoding other properties in compatible would explode their number, so I > would prefer to avoid it. > I would leave other props: > max-speed: hs, ss, ss+, > (optional)size: micro, mini > > I would drop also unpopular/obsolete variants: type-ab, powered, they > can be added later if necessary. > > Just for reference, list of connectors defined by USB (>= 2) specifications: > 1. USB 2.0 (with later amendments): > - Standard-A plug and receptacle > - Standard-B plug and receptacle > - Mini-B plug and receptacle > - Micro-B plug and receptacle > - Micro-AB receptacle > - Micro-A plug > 2. USB 3.0: > - USB 3.0 Standard-A plug and receptacle > - USB 3.0 Standard-B plug and receptacle > - USB 3.0 Powered-B plug and receptacle > - USB 3.0 Micro-B plug and receptacle > - USB 3.0 Micro-A plug > - USB 3.0 Micro-AB receptacle > 3. USB 3.1: > - Enhanced SuperSpeed Standard-A plug and receptacle > - Enhanced SuperSpeed Standard-B plug and receptacle > - Enhanced SuperSpeed Micro-B plug and receptacle > - Enhanced SuperSpeed Micro-A plug > - Enhanced SuperSpeed Micro-AB receptacle > 4. USB-C (release 1.3): > - USB Full-Featured Type-C receptacle > - USB 2.0 Type-C receptacle > - USB Full-Featured Type-C plug > - USB 2.0 Type-C plug > - USB Type-C Power-Only plug > >>> 3. Numbering of port/remote nodes, currently only 0 is assigned for Interface >>> Controller. Maybe other functions should be also assigned: >>> HS, SS, CC, SBU, ... whatever. Maybe functions should be described >>> as an additional property of remote node? >> child of the controller is also an option. There's already prec > > Shall we support both solutions or just make one mandatory? Oops, I was just going to say for display, there's already precedent that ports are used. So that means at least SS should just be described with ports. Then HS probably should be a port too just to be symmetrical. The connector being a child of the USB-PD (or other controller chip) is probably the only thing that makes sense. I guess the question is whether there are cases where that doesn't make sense. >>> --- >>> .../bindings/connector/usb-connector.txt | 49 ++++++++++++++++++++++ >>> 1 file changed, 49 insertions(+) >>> create mode 100644 Documentation/devicetree/bindings/connector/usb-connector.txt >>> >>> diff --git a/Documentation/devicetree/bindings/connector/usb-connector.txt b/Documentation/devicetree/bindings/connector/usb-connector.txt >>> new file mode 100644 >>> index 000000000000..f3a4e85122d5 >>> --- /dev/null >>> +++ b/Documentation/devicetree/bindings/connector/usb-connector.txt >>> @@ -0,0 +1,49 @@ >>> +USB Connector >>> +============= >>> + >>> +Required properties: >>> +- compatible: "usb-connector" >>> + connectors with vendor specific extensions can add one of additional >>> + compatibles: >>> + "samsung,usb-connector-11pin": 11-pin Samsung micro-USB connector >>> +- type: the USB connector type: "a", "b", "ab", "c" >>> +- max-mode: max USB speed mode supported by the connector: >>> + "ls", "fs", "hs", "ss", "ss+" >> Do we really see cases where the connector is slower than the >> controller? Plus things like "ls" with an type A connector are not >> valid. > > For example Galaxy Note 4 - it has USB3 controller and micro-USB 2.0 > connector. How does one distinguish a micro-B SS connector with a HS plug vs. a SS plug? It must be at run-time. Wouldn't a HS connector behave operate the same as the former case? If we do need to distinguish here, then I think it should be by compatible. Say "usb-ss-b-connector"? >>> +Optional properties: >>> +- label: a symbolic name for the connector >>> +- size: size of the connector, should be specified in case of >>> + non-standard USB connectors: "mini", "micro", "powered" >> What does powered mean? > > It is standard-B connector with additional power pins, as defined in > USB3.0 spec, we can drop it as not-popular one. Okay. Nothing about it on wikipedia. >> >> This is really "type" if you compare to HDMI. > > As type is already used, I have to use other word, maybe 'form' would > be better. But you've dropped type in favor of compatible strings, so you can add it back to replace size and keep the meaning aligned with HDMI. >>> + >>> +Required nodes: >>> +- any data bus to the connector should be modeled using the >>> + OF graph bindings specified in bindings/graph.txt. >>> + There should be exactly one port with at least one endpoint to >>> + different device nodes. The first endpoint (reg = <0>) should >>> + point to USB Interface Controller. >>> + >>> +Example >>> +------- >>> + >>> +musb_con: connector { >>> + compatible = "samsung,usb-connector-11pin", "usb-connector"; >>> + label = "usb"; >>> + type = "b"; >>> + size = "micro"; >>> + max-mode = "hs"; >> These all are implied by "samsung,usb-connector-11pin". > > Yes, but "usb-connector" compatible requires/permits it, or am I wrong ? Yes, but we're mixing where the compatible implies all the information and where it's separate fields. >>> + port { >>> + #address-cells = <1>; >>> + #size-cells = <0>; >>> + >>> + musb_con_usb_in: endpoint@0 { >>> + reg = <0>; >>> + remote-endpoint = <&muic_usb_out>; >>> + }; >>> + >>> + musb_con_mhl_in: endpoint@1 { >>> + reg = <1>; >>> + remote-endpoint = <&mhl_out>; >>> + }; >> I think this should be 2 ports, not 2 endpoints. Think of ports as >> different data streams and endpoints are either the same data stream >> muxed or fanned out depending on direction. Now for Type-C, 1 port for >> USB and alternate modes is probably correct. > > I agree for ports. > Regarding type-c, it has separate lines for HS and for SS. HS lines > often go to Interface Controller as they can be used to legacy detection > methods and alternatively muxed to UART. > SS lines go directly to USB3 chip, see for example TPS65982 [1][2]. For > me it is an argument against merging SS and HS lines into one port. What > do you think? If you support USB3 and HDMI/DP alternate modes, there has to be a mux somewhere. It could be on the SoC or external chip. > My proposition of port numbering: > 0: ID for type-B, CC for type-C I'd expect ID is just a GPIO line, phy pin or goes to some control IC. > 1: HS > 2: VBUS - I am not sure if this should be modeled this way, as it is not > a data line, Probably not. Pre USB-PD, it's going to be a regulator supply or sink or goes to some control IC. In the last case, we just need a phandle reference of some sort. For USB-PD, I'd expect that Vbus, CC, SBU and perhaps all the SS lines are just routed to some controller. Maybe just need a similar phandle reference. > 3: SS > 4: SBU Handling these is probably somewhat out of scope of the connector. HDMI expects to have a "ddc-i2c-bus" and hpd-gpios properties typically. Where do we put those in this use case? Rob
On 06.10.2017 19:23, Rob Herring wrote: > On Fri, Oct 6, 2017 at 6:10 AM, Andrzej Hajda <a.hajda@samsung.com> wrote: >> Hi Rob, >> >> Thanks for review. >> >> On 06.10.2017 01:12, Rob Herring wrote: >>> On Thu, Sep 28, 2017 at 03:07:27PM +0200, Andrzej Hajda wrote: >>>> These bindings allows to describe most known standard USB connectors >>>> and it should be possible to extend it if necessary. >>>> USB connectors, beside USB can be used to route other protocols, >>>> for example UART, Audio, MHL. In such case every device passing data >>>> through the connector should have appropriate graph bindings. >>> Yay! >>> >>>> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> >>>> --- >>>> There are few things for discussion (IMO): >>>> 1. vendor specific connectors, I have added them here, but maybe better is >>>> to place them in separate files. >>> I'd worry about the standard connectors first, but probably good to have >>> an idea of how vendor connectors need to be extended. >>> >>>> 2. physical connector description - I have split it to three properties: >>>> type(a,b,ab,c), max-mode(ls,fs,hs,ss,ss+), size(mini,micro,powered). >>>> This tripled is able to describe all USB-standard connectors, but there >>>> are also impossible combinations, for example(c, *, micro). Maybe better >>>> would be to just enumerate all possible connectors in include file. >>> We did "type" for hdmi-connector, but I think I'd really prefer >>> compatible be used to distinguish as least where it may matter to s/w. >>> In the HDMI case, they all are pretty much the same, just different >>> physical size. >> I guess that from S/W point of view only matters: >> - which IP is connected to which part of the connector, and this can be >> handled by port node(s), >> - Type: A, B, C >> - probably maximal supported speed of the connector - for example SS+ >> connectors have the same wires but different electrical characteristics >> than SS as I understand, >> >> With this in mind maybe we can drop 'type' and introduce following >> compatibles: >> - usb-a-connector, >> - usb-b-connector, >> - usb-c-connector. >> Encoding other properties in compatible would explode their number, so I >> would prefer to avoid it. >> I would leave other props: >> max-speed: hs, ss, ss+, >> (optional)size: micro, mini >> >> I would drop also unpopular/obsolete variants: type-ab, powered, they >> can be added later if necessary. >> >> Just for reference, list of connectors defined by USB (>= 2) specifications: >> 1. USB 2.0 (with later amendments): >> - Standard-A plug and receptacle >> - Standard-B plug and receptacle >> - Mini-B plug and receptacle >> - Micro-B plug and receptacle >> - Micro-AB receptacle >> - Micro-A plug >> 2. USB 3.0: >> - USB 3.0 Standard-A plug and receptacle >> - USB 3.0 Standard-B plug and receptacle >> - USB 3.0 Powered-B plug and receptacle >> - USB 3.0 Micro-B plug and receptacle >> - USB 3.0 Micro-A plug >> - USB 3.0 Micro-AB receptacle >> 3. USB 3.1: >> - Enhanced SuperSpeed Standard-A plug and receptacle >> - Enhanced SuperSpeed Standard-B plug and receptacle >> - Enhanced SuperSpeed Micro-B plug and receptacle >> - Enhanced SuperSpeed Micro-A plug >> - Enhanced SuperSpeed Micro-AB receptacle >> 4. USB-C (release 1.3): >> - USB Full-Featured Type-C receptacle >> - USB 2.0 Type-C receptacle >> - USB Full-Featured Type-C plug >> - USB 2.0 Type-C plug >> - USB Type-C Power-Only plug >> >>>> 3. Numbering of port/remote nodes, currently only 0 is assigned for Interface >>>> Controller. Maybe other functions should be also assigned: >>>> HS, SS, CC, SBU, ... whatever. Maybe functions should be described >>>> as an additional property of remote node? >>> child of the controller is also an option. There's already prec >> Shall we support both solutions or just make one mandatory? > Oops, I was just going to say for display, there's already precedent > that ports are used. So that means at least SS should just be > described with ports. Then HS probably should be a port too just to be > symmetrical. > > The connector being a child of the USB-PD (or other controller chip) > is probably the only thing that makes sense. I guess the question is > whether there are cases where that doesn't make sense. > >>>> --- >>>> .../bindings/connector/usb-connector.txt | 49 ++++++++++++++++++++++ >>>> 1 file changed, 49 insertions(+) >>>> create mode 100644 Documentation/devicetree/bindings/connector/usb-connector.txt >>>> >>>> diff --git a/Documentation/devicetree/bindings/connector/usb-connector.txt b/Documentation/devicetree/bindings/connector/usb-connector.txt >>>> new file mode 100644 >>>> index 000000000000..f3a4e85122d5 >>>> --- /dev/null >>>> +++ b/Documentation/devicetree/bindings/connector/usb-connector.txt >>>> @@ -0,0 +1,49 @@ >>>> +USB Connector >>>> +============= >>>> + >>>> +Required properties: >>>> +- compatible: "usb-connector" >>>> + connectors with vendor specific extensions can add one of additional >>>> + compatibles: >>>> + "samsung,usb-connector-11pin": 11-pin Samsung micro-USB connector >>>> +- type: the USB connector type: "a", "b", "ab", "c" >>>> +- max-mode: max USB speed mode supported by the connector: >>>> + "ls", "fs", "hs", "ss", "ss+" >>> Do we really see cases where the connector is slower than the >>> controller? Plus things like "ls" with an type A connector are not >>> valid. >> For example Galaxy Note 4 - it has USB3 controller and micro-USB 2.0 >> connector. > How does one distinguish a micro-B SS connector with a HS plug vs. a > SS plug? It must be at run-time.Wouldn't a HS connector behave > operate the same as the former case? > > If we do need to distinguish here, then I think it should be by > compatible. Say "usb-ss-b-connector"? I guess that from S/W POV we may need it only in corner cases, but it could be also good to have this distinction even for informative purposes. But if we want to encode it in compatible we can end up with: usb-a-connector usb-ss-a-connector usb-ssplus-a-connector usb-b-connector usb-ss-b-connector usb-ssplus-b-connector usb-c-connector usb-ss-c-connector I see no big problem with it, but I do not see advantage over separate property 'max-speed', or maybe better 'max-mode'. I suppose I miss some important DT principles, what is the rationale behind encoding such things in compatibles. > >>>> +Optional properties: >>>> +- label: a symbolic name for the connector >>>> +- size: size of the connector, should be specified in case of >>>> + non-standard USB connectors: "mini", "micro", "powered" >>> What does powered mean? >> It is standard-B connector with additional power pins, as defined in >> USB3.0 spec, we can drop it as not-popular one. > Okay. Nothing about it on wikipedia. > >>> This is really "type" if you compare to HDMI. >> As type is already used, I have to use other word, maybe 'form' would >> be better. > But you've dropped type in favor of compatible strings, so you can add > it back to replace size and keep the meaning aligned with HDMI. OK. > >>>> + >>>> +Required nodes: >>>> +- any data bus to the connector should be modeled using the >>>> + OF graph bindings specified in bindings/graph.txt. >>>> + There should be exactly one port with at least one endpoint to >>>> + different device nodes. The first endpoint (reg = <0>) should >>>> + point to USB Interface Controller. >>>> + >>>> +Example >>>> +------- >>>> + >>>> +musb_con: connector { >>>> + compatible = "samsung,usb-connector-11pin", "usb-connector"; >>>> + label = "usb"; >>>> + type = "b"; >>>> + size = "micro"; >>>> + max-mode = "hs"; >>> These all are implied by "samsung,usb-connector-11pin". >> Yes, but "usb-connector" compatible requires/permits it, or am I wrong ? > Yes, but we're mixing where the compatible implies all the information > and where it's separate fields. So how 11-pin connector should be described? > >>>> + port { >>>> + #address-cells = <1>; >>>> + #size-cells = <0>; >>>> + >>>> + musb_con_usb_in: endpoint@0 { >>>> + reg = <0>; >>>> + remote-endpoint = <&muic_usb_out>; >>>> + }; >>>> + >>>> + musb_con_mhl_in: endpoint@1 { >>>> + reg = <1>; >>>> + remote-endpoint = <&mhl_out>; >>>> + }; >>> I think this should be 2 ports, not 2 endpoints. Think of ports as >>> different data streams and endpoints are either the same data stream >>> muxed or fanned out depending on direction. Now for Type-C, 1 port for >>> USB and alternate modes is probably correct. >> I agree for ports. >> Regarding type-c, it has separate lines for HS and for SS. HS lines >> often go to Interface Controller as they can be used to legacy detection >> methods and alternatively muxed to UART. >> SS lines go directly to USB3 chip, see for example TPS65982 [1][2]. For >> me it is an argument against merging SS and HS lines into one port. What >> do you think? > If you support USB3 and HDMI/DP alternate modes, there has to be a mux > somewhere. It could be on the SoC or external chip. Yes. In the device I am working on it is in USB3 phy, but this mux is only for SS lines. > >> My proposition of port numbering: >> 0: ID for type-B, CC for type-C > I'd expect ID is just a GPIO line, phy pin or goes to some control IC. Yes, ID and CC should not be described by graph at all if the connector is the child of InterfaceController. > >> 1: HS >> 2: VBUS - I am not sure if this should be modeled this way, as it is not >> a data line, > Probably not. Pre USB-PD, it's going to be a regulator supply or sink > or goes to some control IC. In the last case, we just need a phandle > reference of some sort. For USB-PD, I'd expect that Vbus, CC, SBU and > perhaps all the SS lines are just routed to some controller. Maybe > just need a similar phandle reference. Yes, phandle is something more appropriate here, I am not sure only how it will work with current kernel frameworks, but this is different issue. > >> 3: SS >> 4: SBU > Handling these is probably somewhat out of scope of the connector. Why? This is integral part of the connector. > HDMI expects to have a "ddc-i2c-bus" and hpd-gpios properties > typically. Where do we put those in this use case? In case of USB-C DP Alt mode: - HPD is encapsulated in USB-PD messages, - DDC is encapsulated in DP-AUX channel which goes via SBU lines, In case of USB-C HDMI Alt-mode: - DDC is encapsulated in USB-PD messages, - HPD is passed together with HEAC and utility via SBU lines. In USB-A, USB-B, USB-C without alt modes these signals does not make sense. Do we need ddc-i2c-bus and hpd-gpios properties in USB connector? Regards Andrzej
Hi Andrzej, Thank you for the patch. On Thursday, 28 September 2017 16:07:27 EEST Andrzej Hajda wrote: > These bindings allows to describe most known standard USB connectors > and it should be possible to extend it if necessary. > USB connectors, beside USB can be used to route other protocols, > for example UART, Audio, MHL. In such case every device passing data > through the connector should have appropriate graph bindings. > > Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> > --- > There are few things for discussion (IMO): > 1. vendor specific connectors, I have added them here, but maybe better is > to place them in separate files. It's useful to have one vendor-specific compatible string to be used in the example. We could split vendor-specific connectors to separate files later if needed, but for now I'm fine keeping them here. > 2. physical connector description - I have split it to three properties: > type(a,b,ab,c), max-mode(ls,fs,hs,ss,ss+), size(mini,micro,powered). > This tripled is able to describe all USB-standard connectors, but there > are also impossible combinations, for example(c, *, micro). Maybe better > would be to just enumerate all possible connectors in include file. I don't have a strong opinion on this. The three properties are nicely descriptive. You might want to list the valid combinations in the bindings though. > 3. Numbering of port/remote nodes, currently only 0 is assigned for > Interface Controller. Maybe other functions should be also assigned: > HS, SS, CC, SBU, ... whatever. Maybe functions should be described > as an additional property of remote node? Given that one of the main reasons this binding is needed is to describe MHL connection to a USB connector, I think we'll need to define additional functions, yes. I'm not sure yet how that should look like though. > --- > .../bindings/connector/usb-connector.txt | 49 +++++++++++++++++++ > 1 file changed, 49 insertions(+) > create mode 100644 > Documentation/devicetree/bindings/connector/usb-connector.txt > > diff --git a/Documentation/devicetree/bindings/connector/usb-connector.txt > b/Documentation/devicetree/bindings/connector/usb-connector.txt new file > mode 100644 > index 000000000000..f3a4e85122d5 > --- /dev/null > +++ b/Documentation/devicetree/bindings/connector/usb-connector.txt > @@ -0,0 +1,49 @@ > +USB Connector > +============= > + > +Required properties: > +- compatible: "usb-connector" > + connectors with vendor specific extensions can add one of additional > + compatibles: > + "samsung,usb-connector-11pin": 11-pin Samsung micro-USB connector > +- type: the USB connector type: "a", "b", "ab", "c" > +- max-mode: max USB speed mode supported by the connector: > + "ls", "fs", "hs", "ss", "ss+" > + > +Optional properties: > +- label: a symbolic name for the connector > +- size: size of the connector, should be specified in case of > + non-standard USB connectors: "mini", "micro", "powered" "non-standard" sounds like "vendor-specific", while I assume you're talking about the size. The USB specification uses the term "standard" for this purpose, so it's hard to use another one that would convey the right meaning precisely. Maybe "non-standard ('large') USB connector sizes" ? > +Required nodes: > +- any data bus to the connector should be modeled using the > + OF graph bindings specified in bindings/graph.txt. > + There should be exactly one port with at least one endpoint to > + different device nodes. The first endpoint (reg = <0>) should > + point to USB Interface Controller. > + > +Example > +------- > + > +musb_con: connector { > + compatible = "samsung,usb-connector-11pin", "usb-connector"; > + label = "usb"; > + type = "b"; > + size = "micro"; > + max-mode = "hs"; > + > + port { > + #address-cells = <1>; > + #size-cells = <0>; > + > + musb_con_usb_in: endpoint@0 { > + reg = <0>; > + remote-endpoint = <&muic_usb_out>; > + }; > + > + musb_con_mhl_in: endpoint@1 { > + reg = <1>; > + remote-endpoint = <&mhl_out>; > + }; > + }; > +};
Hi Andrzej, On Wednesday, 18 October 2017 18:11:25 EEST Laurent Pinchart wrote: > On Thursday, 28 September 2017 16:07:27 EEST Andrzej Hajda wrote: > > These bindings allows to describe most known standard USB connectors > > and it should be possible to extend it if necessary. > > USB connectors, beside USB can be used to route other protocols, > > for example UART, Audio, MHL. In such case every device passing data > > through the connector should have appropriate graph bindings. > > > > Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> > > --- > > There are few things for discussion (IMO): > > 1. vendor specific connectors, I have added them here, but maybe better is > > > > to place them in separate files. > > It's useful to have one vendor-specific compatible string to be used in the > example. We could split vendor-specific connectors to separate files later > if needed, but for now I'm fine keeping them here. > > > 2. physical connector description - I have split it to three properties: > > type(a,b,ab,c), max-mode(ls,fs,hs,ss,ss+), size(mini,micro,powered). > > This tripled is able to describe all USB-standard connectors, but there > > are also impossible combinations, for example(c, *, micro). Maybe > > better > > would be to just enumerate all possible connectors in include file. > > I don't have a strong opinion on this. The three properties are nicely > descriptive. You might want to list the valid combinations in the bindings > though. > > > 3. Numbering of port/remote nodes, currently only 0 is assigned for > > > > Interface Controller. Maybe other functions should be also assigned: > > HS, SS, CC, SBU, ... whatever. Maybe functions should be described > > as an additional property of remote node? > > Given that one of the main reasons this binding is needed is to describe MHL > connection to a USB connector, I think we'll need to define additional > functions, yes. I'm not sure yet how that should look like though. > > --- > > > > .../bindings/connector/usb-connector.txt | 49 +++++++++++++++++ > > 1 file changed, 49 insertions(+) > > create mode 100644 > > > > Documentation/devicetree/bindings/connector/usb-connector.txt > > > > diff --git a/Documentation/devicetree/bindings/connector/usb-connector.txt > > b/Documentation/devicetree/bindings/connector/usb-connector.txt new file > > mode 100644 > > index 000000000000..f3a4e85122d5 > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/connector/usb-connector.txt > > @@ -0,0 +1,49 @@ > > +USB Connector > > +============= > > + > > +Required properties: > > +- compatible: "usb-connector" > > + connectors with vendor specific extensions can add one of additional > > + compatibles: > > + "samsung,usb-connector-11pin": 11-pin Samsung micro-USB connector > > +- type: the USB connector type: "a", "b", "ab", "c" > > +- max-mode: max USB speed mode supported by the connector: > > + "ls", "fs", "hs", "ss", "ss+" > > + > > +Optional properties: > > +- label: a symbolic name for the connector > > +- size: size of the connector, should be specified in case of > > + non-standard USB connectors: "mini", "micro", "powered" > > "non-standard" sounds like "vendor-specific", while I assume you're talking > about the size. The USB specification uses the term "standard" for this > purpose, so it's hard to use another one that would convey the right meaning > precisely. Maybe "non-standard ('large') USB connector sizes" ? > > > +Required nodes: > > +- any data bus to the connector should be modeled using the > > + OF graph bindings specified in bindings/graph.txt. > > + There should be exactly one port with at least one endpoint to > > + different device nodes. The first endpoint (reg = <0>) should > > + point to USB Interface Controller. > > + > > +Example > > +------- > > + > > +musb_con: connector { > > + compatible = "samsung,usb-connector-11pin", "usb-connector"; > > + label = "usb"; > > + type = "b"; > > + size = "micro"; > > + max-mode = "hs"; > > + > > + port { > > + #address-cells = <1>; > > + #size-cells = <0>; > > + > > + musb_con_usb_in: endpoint@0 { > > + reg = <0>; > > + remote-endpoint = <&muic_usb_out>; > > + }; > > + > > + musb_con_mhl_in: endpoint@1 { > > + reg = <1>; > > + remote-endpoint = <&mhl_out>; > > + }; > > + }; > > +}; One more comment, do I assume correctly that the Samsung 11-pin connector carries USB and MHL on different pins ?
Hi Laurent, Thank you for the review. On 18.10.2017 17:11, Laurent Pinchart wrote: > Hi Andrzej, > > Thank you for the patch. > > On Thursday, 28 September 2017 16:07:27 EEST Andrzej Hajda wrote: >> These bindings allows to describe most known standard USB connectors >> and it should be possible to extend it if necessary. >> USB connectors, beside USB can be used to route other protocols, >> for example UART, Audio, MHL. In such case every device passing data >> through the connector should have appropriate graph bindings. >> >> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> >> --- >> There are few things for discussion (IMO): >> 1. vendor specific connectors, I have added them here, but maybe better is >> to place them in separate files. > It's useful to have one vendor-specific compatible string to be used in the > example. We could split vendor-specific connectors to separate files later if > needed, but for now I'm fine keeping them here. > >> 2. physical connector description - I have split it to three properties: >> type(a,b,ab,c), max-mode(ls,fs,hs,ss,ss+), size(mini,micro,powered). >> This tripled is able to describe all USB-standard connectors, but there >> are also impossible combinations, for example(c, *, micro). Maybe better >> would be to just enumerate all possible connectors in include file. > I don't have a strong opinion on this. The three properties are nicely > descriptive. You might want to list the valid combinations in the bindings > though. According to Rob's suggestion in next iteration I will encode USB port type into compatible ie: - usb-a-connector, - usb-b-connector, - usb-c-connector. Rob suggested also to encode there speed as well, but I am afraid it will inflate number of compatibles: (3 types: a, b, c) x (3 speed modes: hs, ss, ssplus) = 9 combinations >> 3. Numbering of port/remote nodes, currently only 0 is assigned for >> Interface Controller. Maybe other functions should be also assigned: >> HS, SS, CC, SBU, ... whatever. Maybe functions should be described >> as an additional property of remote node? > Given that one of the main reasons this binding is needed is to describe MHL > connection to a USB connector, I think we'll need to define additional > functions, yes. I'm not sure yet how that should look like though. Current idea is to encode it in port number. > >> --- >> .../bindings/connector/usb-connector.txt | 49 +++++++++++++++++++ >> 1 file changed, 49 insertions(+) >> create mode 100644 >> Documentation/devicetree/bindings/connector/usb-connector.txt >> >> diff --git a/Documentation/devicetree/bindings/connector/usb-connector.txt >> b/Documentation/devicetree/bindings/connector/usb-connector.txt new file >> mode 100644 >> index 000000000000..f3a4e85122d5 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/connector/usb-connector.txt >> @@ -0,0 +1,49 @@ >> +USB Connector >> +============= >> + >> +Required properties: >> +- compatible: "usb-connector" >> + connectors with vendor specific extensions can add one of additional >> + compatibles: >> + "samsung,usb-connector-11pin": 11-pin Samsung micro-USB connector >> +- type: the USB connector type: "a", "b", "ab", "c" >> +- max-mode: max USB speed mode supported by the connector: >> + "ls", "fs", "hs", "ss", "ss+" >> + >> +Optional properties: >> +- label: a symbolic name for the connector >> +- size: size of the connector, should be specified in case of >> + non-standard USB connectors: "mini", "micro", "powered" > "non-standard" sounds like "vendor-specific", while I assume you're talking > about the size. The USB specification uses the term "standard" for this > purpose, so it's hard to use another one that would convey the right meaning > precisely. Maybe "non-standard ('large') USB connector sizes" ? OK. And answer for your question from other e-mail: > One more comment, do I assume correctly that the Samsung 11-pin connector > carries USB and MHL on different pins ? Yes, there are three additional pins: MHL_DP, MHL_DN and MHL_ID [1]. [1]: https://ae01.alicdn.com/kf/HTB1nn.6KVXXXXaNXFXXq6xXFXXXc/221542210/HTB1nn.6KVXXXXaNXFXXq6xXFXXXc.jpg?size=69211&height=700&width=700&hash=dcababf11610a489d451d7cb0b8ab60e Thanks Andrzej > >> +Required nodes: >> +- any data bus to the connector should be modeled using the >> + OF graph bindings specified in bindings/graph.txt. >> + There should be exactly one port with at least one endpoint to >> + different device nodes. The first endpoint (reg = <0>) should >> + point to USB Interface Controller. >> + >> +Example >> +------- >> + >> +musb_con: connector { >> + compatible = "samsung,usb-connector-11pin", "usb-connector"; >> + label = "usb"; >> + type = "b"; >> + size = "micro"; >> + max-mode = "hs"; >> + >> + port { >> + #address-cells = <1>; >> + #size-cells = <0>; >> + >> + musb_con_usb_in: endpoint@0 { >> + reg = <0>; >> + remote-endpoint = <&muic_usb_out>; >> + }; >> + >> + musb_con_mhl_in: endpoint@1 { >> + reg = <1>; >> + remote-endpoint = <&mhl_out>; >> + }; >> + }; >> +};
diff --git a/Documentation/devicetree/bindings/connector/usb-connector.txt b/Documentation/devicetree/bindings/connector/usb-connector.txt new file mode 100644 index 000000000000..f3a4e85122d5 --- /dev/null +++ b/Documentation/devicetree/bindings/connector/usb-connector.txt @@ -0,0 +1,49 @@ +USB Connector +============= + +Required properties: +- compatible: "usb-connector" + connectors with vendor specific extensions can add one of additional + compatibles: + "samsung,usb-connector-11pin": 11-pin Samsung micro-USB connector +- type: the USB connector type: "a", "b", "ab", "c" +- max-mode: max USB speed mode supported by the connector: + "ls", "fs", "hs", "ss", "ss+" + +Optional properties: +- label: a symbolic name for the connector +- size: size of the connector, should be specified in case of + non-standard USB connectors: "mini", "micro", "powered" + +Required nodes: +- any data bus to the connector should be modeled using the + OF graph bindings specified in bindings/graph.txt. + There should be exactly one port with at least one endpoint to + different device nodes. The first endpoint (reg = <0>) should + point to USB Interface Controller. + +Example +------- + +musb_con: connector { + compatible = "samsung,usb-connector-11pin", "usb-connector"; + label = "usb"; + type = "b"; + size = "micro"; + max-mode = "hs"; + + port { + #address-cells = <1>; + #size-cells = <0>; + + musb_con_usb_in: endpoint@0 { + reg = <0>; + remote-endpoint = <&muic_usb_out>; + }; + + musb_con_mhl_in: endpoint@1 { + reg = <1>; + remote-endpoint = <&mhl_out>; + }; + }; +};
These bindings allows to describe most known standard USB connectors and it should be possible to extend it if necessary. USB connectors, beside USB can be used to route other protocols, for example UART, Audio, MHL. In such case every device passing data through the connector should have appropriate graph bindings. Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> --- There are few things for discussion (IMO): 1. vendor specific connectors, I have added them here, but maybe better is to place them in separate files. 2. physical connector description - I have split it to three properties: type(a,b,ab,c), max-mode(ls,fs,hs,ss,ss+), size(mini,micro,powered). This tripled is able to describe all USB-standard connectors, but there are also impossible combinations, for example(c, *, micro). Maybe better would be to just enumerate all possible connectors in include file. 3. Numbering of port/remote nodes, currently only 0 is assigned for Interface Controller. Maybe other functions should be also assigned: HS, SS, CC, SBU, ... whatever. Maybe functions should be described as an additional property of remote node? ... Regards Andrzej --- .../bindings/connector/usb-connector.txt | 49 ++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 Documentation/devicetree/bindings/connector/usb-connector.txt