| Message ID | 20240223-j7200-usb-suspend-v3-1-b41c9893a130@bootlin.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | usb: cdns: fix suspend on J7200 by assuming reset-on-resume | expand |
On Fri, Feb 23, 2024 at 05:05:25PM +0100, Théo Lebrun wrote: > Compatible can be A or B, not A or B or A+B. Remove last option. > A=ti,j721e-usb and B=ti,am64-usb. > > Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> > --- > Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml | 9 +++------ > 1 file changed, 3 insertions(+), 6 deletions(-) > > diff --git a/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml b/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml > index 95ff9791baea..949f45eb45c2 100644 > --- a/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml > +++ b/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml > @@ -11,12 +11,9 @@ maintainers: > > properties: > compatible: > - oneOf: > - - const: ti,j721e-usb > - - const: ti,am64-usb > - - items: > - - const: ti,j721e-usb > - - const: ti,am64-usb Correct, this makes no sense. The devices seem to be compatible though, so I would expect this to actually be: oneOf: - const: ti,j721e-usb - items: - const: ti,am64-usb - const: ti,j721e-usb > + enum: > + - ti,j721e-usb > + - ti,am64-usb > > reg: > maxItems: 1 > > -- > 2.43.2 >
Hello Conor, On Fri Feb 23, 2024 at 7:12 PM CET, Conor Dooley wrote: > On Fri, Feb 23, 2024 at 05:05:25PM +0100, Théo Lebrun wrote: > > Compatible can be A or B, not A or B or A+B. Remove last option. > > A=ti,j721e-usb and B=ti,am64-usb. > > > > Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> > > --- > > Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml | 9 +++------ > > 1 file changed, 3 insertions(+), 6 deletions(-) > > > > diff --git a/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml b/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml > > index 95ff9791baea..949f45eb45c2 100644 > > --- a/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml > > +++ b/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml > > @@ -11,12 +11,9 @@ maintainers: > > > > properties: > > compatible: > > - oneOf: > > - - const: ti,j721e-usb > > - - const: ti,am64-usb > > - - items: > > - - const: ti,j721e-usb > > - - const: ti,am64-usb > > Correct, this makes no sense. The devices seem to be compatible though, > so I would expect this to actually be: > oneOf: > - const: ti,j721e-usb > - items: > - const: ti,am64-usb > - const: ti,j721e-usb I need your help to grasp what that change is supposed to express? Would you mind turning it into english sentences? A=ti,j721e-usb and B=ti,am64-usb. My understanding of your proposal is that a device can either be compat with A or B. But B is compatible with A so you express it as a list of items. If B is compat with A then A is compat with B. Does the order of items matter? I've not applied your proposal to check for dtbs_check but I'd guess it would throw warnings for the single existing upstream DTSI (as of v6.8-rc6) that uses "ti,am64-usb"? See: arch/arm64/boot/dts/ti/k3-am64-main.dtsi. Thanks Conor! -- Théo Lebrun, Bootlin Embedded Linux and Kernel engineering https://bootlin.com
On Mon, Feb 26, 2024 at 11:33:06AM +0100, Théo Lebrun wrote: > Hello Conor, > > On Fri Feb 23, 2024 at 7:12 PM CET, Conor Dooley wrote: > > On Fri, Feb 23, 2024 at 05:05:25PM +0100, Théo Lebrun wrote: > > > Compatible can be A or B, not A or B or A+B. Remove last option. > > > A=ti,j721e-usb and B=ti,am64-usb. > > > > > > Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> > > > --- > > > Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml | 9 +++------ > > > 1 file changed, 3 insertions(+), 6 deletions(-) > > > > > > diff --git a/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml b/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml > > > index 95ff9791baea..949f45eb45c2 100644 > > > --- a/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml > > > +++ b/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml > > > @@ -11,12 +11,9 @@ maintainers: > > > > > > properties: > > > compatible: > > > - oneOf: > > > - - const: ti,j721e-usb > > > - - const: ti,am64-usb > > > - - items: > > > - - const: ti,j721e-usb > > > - - const: ti,am64-usb > > > > Correct, this makes no sense. The devices seem to be compatible though, > > so I would expect this to actually be: > > oneOf: > > - const: ti,j721e-usb > > - items: > > - const: ti,am64-usb > > - const: ti,j721e-usb > > I need your help to grasp what that change is supposed to express? Would > you mind turning it into english sentences? > A=ti,j721e-usb and B=ti,am64-usb. My understanding of your proposal is > that a device can either be compat with A or B. But B is compatible > with A so you express it as a list of items. If B is compat with A then > A is compat with B. Does the order of items matter? The two devices are compatible with each other, based on an inspection of the driver and the existing "A+B" setup. If this was a newly submitted binding, "B" would not get approved because "A+B" allows support without software changes and all that jazz. Your patch says that allowing "A", "B" and "A+B" makes no sense and you suggest removing "A+B". I am agreeing that it makes no sense to allow all 3 of these situations. What I also noticed is other problems with the binding. What should have been "A+B" is actually documented as "B+A", but that doesn't make sense when the originally supported device is "A". Therefore my suggestion was to only allow "A" and "A+B", which is what we would (hopefully) tell you to do were you submitting the am64 support as a new patch today. > I've not applied your proposal to check for dtbs_check but I'd guess it > would throw warnings for the single existing upstream DTSI (as of > v6.8-rc6) that uses "ti,am64-usb"? See: > arch/arm64/boot/dts/ti/k3-am64-main.dtsi. Yeah, it would but it's not as if that cannot be changed. There's no concerns here about backwards compatibility here, right?
Hello, On Mon Feb 26, 2024 at 12:56 PM CET, Conor Dooley wrote: > On Mon, Feb 26, 2024 at 11:33:06AM +0100, Théo Lebrun wrote: > > Hello Conor, > > > > On Fri Feb 23, 2024 at 7:12 PM CET, Conor Dooley wrote: > > > On Fri, Feb 23, 2024 at 05:05:25PM +0100, Théo Lebrun wrote: > > > > Compatible can be A or B, not A or B or A+B. Remove last option. > > > > A=ti,j721e-usb and B=ti,am64-usb. > > > > > > > > Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> > > > > --- > > > > Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml | 9 +++------ > > > > 1 file changed, 3 insertions(+), 6 deletions(-) > > > > > > > > diff --git a/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml b/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml > > > > index 95ff9791baea..949f45eb45c2 100644 > > > > --- a/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml > > > > +++ b/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml > > > > @@ -11,12 +11,9 @@ maintainers: > > > > > > > > properties: > > > > compatible: > > > > - oneOf: > > > > - - const: ti,j721e-usb > > > > - - const: ti,am64-usb > > > > - - items: > > > > - - const: ti,j721e-usb > > > > - - const: ti,am64-usb > > > > > > Correct, this makes no sense. The devices seem to be compatible though, > > > so I would expect this to actually be: > > > oneOf: > > > - const: ti,j721e-usb > > > - items: > > > - const: ti,am64-usb > > > - const: ti,j721e-usb > > > > I need your help to grasp what that change is supposed to express? Would > > you mind turning it into english sentences? > > A=ti,j721e-usb and B=ti,am64-usb. My understanding of your proposal is > > that a device can either be compat with A or B. But B is compatible > > with A so you express it as a list of items. If B is compat with A then > > A is compat with B. Does the order of items matter? > > The two devices are compatible with each other, based on an inspection of > the driver and the existing "A+B" setup. If this was a newly submitted > binding, "B" would not get approved because "A+B" allows support without > software changes and all that jazz. > > Your patch says that allowing "A", "B" and "A+B" makes no sense and you > suggest removing "A+B". I am agreeing that it makes no sense to allow > all 3 of these situations. > > What I also noticed is other problems with the binding. What should have > been "A+B" is actually documented as "B+A", but that doesn't make sense > when the originally supported device is "A". > > Therefore my suggestion was to only allow "A" and "A+B", which is what > we would (hopefully) tell you to do were you submitting the am64 support > as a new patch today. Thank you for the in-depth explanation! It makes much more sense now, especially the handling of historic stuff that ideally wouldn't have been done this way but that won't be changed from now on. > > I've not applied your proposal to check for dtbs_check but I'd guess it > > would throw warnings for the single existing upstream DTSI (as of > > v6.8-rc6) that uses "ti,am64-usb"? See: > > arch/arm64/boot/dts/ti/k3-am64-main.dtsi. > > Yeah, it would but it's not as if that cannot be changed. There's no > concerns here about backwards compatibility here, right? I'm not involved in the maintenance of this platform so I do not believe I should be answering this question. I asked the question because I taught there always were concerns of backwards-compat when it comes to DT and dt-bindings (in the best of all possible worlds). K3 maintainers are already in cc. Thanks, -- Théo Lebrun, Bootlin Embedded Linux and Kernel engineering https://bootlin.com
On 26/02/24 20:05, Théo Lebrun wrote: > Hello, > > On Mon Feb 26, 2024 at 12:56 PM CET, Conor Dooley wrote: >> On Mon, Feb 26, 2024 at 11:33:06AM +0100, Théo Lebrun wrote: >>> Hello Conor, >>> >>> On Fri Feb 23, 2024 at 7:12 PM CET, Conor Dooley wrote: >>>> On Fri, Feb 23, 2024 at 05:05:25PM +0100, Théo Lebrun wrote: >>>>> Compatible can be A or B, not A or B or A+B. Remove last option. >>>>> A=ti,j721e-usb and B=ti,am64-usb. >>>>> >>>>> Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> >>>>> --- >>>>> Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml | 9 +++------ >>>>> 1 file changed, 3 insertions(+), 6 deletions(-) >>>>> >>>>> diff --git a/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml b/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml >>>>> index 95ff9791baea..949f45eb45c2 100644 >>>>> --- a/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml >>>>> +++ b/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml >>>>> @@ -11,12 +11,9 @@ maintainers: >>>>> >>>>> properties: >>>>> compatible: >>>>> - oneOf: >>>>> - - const: ti,j721e-usb >>>>> - - const: ti,am64-usb >>>>> - - items: >>>>> - - const: ti,j721e-usb >>>>> - - const: ti,am64-usb >>>> >>>> Correct, this makes no sense. The devices seem to be compatible though, >>>> so I would expect this to actually be: >>>> oneOf: >>>> - const: ti,j721e-usb >>>> - items: >>>> - const: ti,am64-usb >>>> - const: ti,j721e-usb >>> >>> I need your help to grasp what that change is supposed to express? Would >>> you mind turning it into english sentences? >>> A=ti,j721e-usb and B=ti,am64-usb. My understanding of your proposal is >>> that a device can either be compat with A or B. But B is compatible >>> with A so you express it as a list of items. If B is compat with A then >>> A is compat with B. Does the order of items matter? >> >> The two devices are compatible with each other, based on an inspection of >> the driver and the existing "A+B" setup. If this was a newly submitted >> binding, "B" would not get approved because "A+B" allows support without >> software changes and all that jazz. >> >> Your patch says that allowing "A", "B" and "A+B" makes no sense and you >> suggest removing "A+B". I am agreeing that it makes no sense to allow >> all 3 of these situations. >> >> What I also noticed is other problems with the binding. What should have >> been "A+B" is actually documented as "B+A", but that doesn't make sense >> when the originally supported device is "A". >> >> Therefore my suggestion was to only allow "A" and "A+B", which is what >> we would (hopefully) tell you to do were you submitting the am64 support >> as a new patch today. > > Thank you for the in-depth explanation! It makes much more sense now, > especially the handling of historic stuff that ideally wouldn't have > been done this way but that won't be changed from now on. > IIRC, idea behind adding new compatible for AM64 even though register map is very much compatible is just being future proof as AM64 and J721e belong to different product groups and thus have differences wrt SoC level integration etc which may need SoC specific handling later on. I don't see any DT (now or in the past) using compatible = B,A or compatible = A,B So do we really need A+B to be supported by binding? Also, note that AM64 SoC support was added long after J721e. So ideally should be B+A if at all we need a fallback compatible. Regards Vignesh
On Tue, Feb 27, 2024 at 09:54:30AM +0530, Vignesh Raghavendra wrote: > On 26/02/24 20:05, Théo Lebrun wrote: > > On Mon Feb 26, 2024 at 12:56 PM CET, Conor Dooley wrote: > >> On Mon, Feb 26, 2024 at 11:33:06AM +0100, Théo Lebrun wrote: > >>> Hello Conor, > >>> > >>> On Fri Feb 23, 2024 at 7:12 PM CET, Conor Dooley wrote: > >>>> On Fri, Feb 23, 2024 at 05:05:25PM +0100, Théo Lebrun wrote: > >>>>> Compatible can be A or B, not A or B or A+B. Remove last option. > >>>>> A=ti,j721e-usb and B=ti,am64-usb. > >>>>> > >>>>> Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> > >>>>> --- > >>>>> Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml | 9 +++------ > >>>>> 1 file changed, 3 insertions(+), 6 deletions(-) > >>>>> > >>>>> diff --git a/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml b/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml > >>>>> index 95ff9791baea..949f45eb45c2 100644 > >>>>> --- a/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml > >>>>> +++ b/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml > >>>>> @@ -11,12 +11,9 @@ maintainers: > >>>>> > >>>>> properties: > >>>>> compatible: > >>>>> - oneOf: > >>>>> - - const: ti,j721e-usb > >>>>> - - const: ti,am64-usb > >>>>> - - items: > >>>>> - - const: ti,j721e-usb > >>>>> - - const: ti,am64-usb > >>>> > >>>> Correct, this makes no sense. The devices seem to be compatible though, > >>>> so I would expect this to actually be: > >>>> oneOf: > >>>> - const: ti,j721e-usb > >>>> - items: > >>>> - const: ti,am64-usb > >>>> - const: ti,j721e-usb > >>> > >>> I need your help to grasp what that change is supposed to express? Would > >>> you mind turning it into english sentences? > >>> A=ti,j721e-usb and B=ti,am64-usb. My understanding of your proposal is > >>> that a device can either be compat with A or B. But B is compatible > >>> with A so you express it as a list of items. If B is compat with A then > >>> A is compat with B. Does the order of items matter? > >> > >> The two devices are compatible with each other, based on an inspection of > >> the driver and the existing "A+B" setup. If this was a newly submitted > >> binding, "B" would not get approved because "A+B" allows support without > >> software changes and all that jazz. > >> > >> Your patch says that allowing "A", "B" and "A+B" makes no sense and you > >> suggest removing "A+B". I am agreeing that it makes no sense to allow > >> all 3 of these situations. > >> > >> What I also noticed is other problems with the binding. What should have > >> been "A+B" is actually documented as "B+A", but that doesn't make sense > >> when the originally supported device is "A". This A and B stuff confused me, I should just have used the actual compatibles. I meant | What should have been "B+A" is actually documented as "A+B", but that | doesn't make sense when the originally supported device is "A" > >> > >> Therefore my suggestion was to only allow "A" and "A+B", which is what > >> we would (hopefully) tell you to do were you submitting the am64 support > >> as a new patch today. > > > > Thank you for the in-depth explanation! It makes much more sense now, > > especially the handling of historic stuff that ideally wouldn't have > > been done this way but that won't be changed from now on. > > > > IIRC, idea behind adding new compatible for AM64 even though register > map is very much compatible is just being future proof as AM64 and J721e > belong to different product groups and thus have differences wrt SoC > level integration etc which may need SoC specific handling later on. That is fine, I don't think anyone here is disputing a soc-specific compatible existing for this device. > Also, note that AM64 SoC support was added long after J721e. So ideally > should be B+A if at all we need a fallback compatible. Correct, I accidentally wrote "A+B", but you can see that that conflicted with the actual example I had given above. > I don't see any DT (now or in the past) using > > compatible = B,A or compatible = A,B > > So do we really need A+B to be supported by binding? Given the mistake, I am going to take this as meaning should the fallback be supported. My take is that if we are going to remove something, it should be "ti,am64-usb" isolation that should go. The devicetrees can be update without concerns about compatibility. Cheers, Conor.
diff --git a/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml b/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml index 95ff9791baea..949f45eb45c2 100644 --- a/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml +++ b/Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml @@ -11,12 +11,9 @@ maintainers: properties: compatible: - oneOf: - - const: ti,j721e-usb - - const: ti,am64-usb - - items: - - const: ti,j721e-usb - - const: ti,am64-usb + enum: + - ti,j721e-usb + - ti,am64-usb reg: maxItems: 1
Compatible can be A or B, not A or B or A+B. Remove last option. A=ti,j721e-usb and B=ti,am64-usb. Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> --- Documentation/devicetree/bindings/usb/ti,j721e-usb.yaml | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-)