diff mbox series

[v2,1/3] dt-bindings: media: ov772x: Document endpoint properties

Message ID 1596454753-13612-2-git-send-email-prabhakar.mahadev-lad.rj@bp.renesas.com
State Changes Requested
Headers show
Series media: i2c: ov772x: Enable BT656 mode and test pattern support | expand

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Commit Message

Lad Prabhakar Aug. 3, 2020, 11:39 a.m. UTC
Document endpoint properties required for parallel interface

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
 .../devicetree/bindings/media/i2c/ov772x.txt     | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

Comments

Jacopo Mondi Aug. 6, 2020, 2:35 p.m. UTC | #1
Hi Prabhakar,

On Mon, Aug 03, 2020 at 12:39:11PM +0100, Lad Prabhakar wrote:
> Document endpoint properties required for parallel interface
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> ---
>  .../devicetree/bindings/media/i2c/ov772x.txt     | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/media/i2c/ov772x.txt b/Documentation/devicetree/bindings/media/i2c/ov772x.txt
> index 0b3ede5b8e6a..1f4153484717 100644
> --- a/Documentation/devicetree/bindings/media/i2c/ov772x.txt
> +++ b/Documentation/devicetree/bindings/media/i2c/ov772x.txt
> @@ -21,6 +21,22 @@ subnode for its digital output video port, in accordance with the video
>  interface bindings defined in Documentation/devicetree/bindings/media/
>  video-interfaces.txt.
>
> +Endpoint node required properties for parallel connection are:
> +- remote-endpoint: a phandle to the bus receiver's endpoint node.

we allow endpoints without a remote end connected usually. They can be
filled in later, in example, with an overlay.

> +- bus-width: shall be set to <8> for 8 bits parallel bus
> +	     or <10> for 10 bits parallel bus
> +- data-shift: shall be set to <2> for 8 bits parallel bus
> +	      (lines 9:2 are used) or <0> for 10 bits parallel bus

defining what is required or optional might be hard. I don't see the
driver enforcing their presence and I assume they have safe default.
Maybe make them optional and specify what the defaul value is ?


> +- hsync-active: active state of the HSYNC signal, 0/1 for LOW/HIGH respectively.
> +		(Not required for bus-type equal 6)
> +- vsync-active: active state of the VSYNC signal, 0/1 for LOW/HIGH respectively.
> +		(Not required for bus-type equal 6)

If they're not required, they're optional, aren't they ? :)

> +- pclk-sample: sample data on rising (1) or falling (0) edge of the pixel clock
> +	       signal. (Not required for bus-type equal 6)

Why the pclk polarity is does not apply to BT.656 ?

> +- bus-type: data bus type. Possible values are:
> +	    5 - Parallel
> +	    6 - Bt.656

Are we making this required, or do we expect this to be deduced
depending on which other properties have been specified ? Sakari it
seems you would like this to become a properties that has to be
specified most of the times, right ? (I tend to agree with that FWIW),
but does it impact retro-compatibility ?

> +
>  Example:
>
>  &i2c0 {
> --
> 2.17.1
>
Lad, Prabhakar Aug. 10, 2020, 7:22 a.m. UTC | #2
Hi Jacopo,

Thank you for the review.

On Thu, Aug 6, 2020 at 3:32 PM Jacopo Mondi <jacopo@jmondi.org> wrote:
>
> Hi Prabhakar,
>
> On Mon, Aug 03, 2020 at 12:39:11PM +0100, Lad Prabhakar wrote:
> > Document endpoint properties required for parallel interface
> >
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > ---
> >  .../devicetree/bindings/media/i2c/ov772x.txt     | 16 ++++++++++++++++
> >  1 file changed, 16 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/media/i2c/ov772x.txt b/Documentation/devicetree/bindings/media/i2c/ov772x.txt
> > index 0b3ede5b8e6a..1f4153484717 100644
> > --- a/Documentation/devicetree/bindings/media/i2c/ov772x.txt
> > +++ b/Documentation/devicetree/bindings/media/i2c/ov772x.txt
> > @@ -21,6 +21,22 @@ subnode for its digital output video port, in accordance with the video
> >  interface bindings defined in Documentation/devicetree/bindings/media/
> >  video-interfaces.txt.
> >
> > +Endpoint node required properties for parallel connection are:
> > +- remote-endpoint: a phandle to the bus receiver's endpoint node.
>
> we allow endpoints without a remote end connected usually. They can be
> filled in later, in example, with an overlay.
>
Agreed.

> > +- bus-width: shall be set to <8> for 8 bits parallel bus
> > +          or <10> for 10 bits parallel bus
> > +- data-shift: shall be set to <2> for 8 bits parallel bus
> > +           (lines 9:2 are used) or <0> for 10 bits parallel bus
>
> defining what is required or optional might be hard. I don't see the
> driver enforcing their presence and I assume they have safe default.
> Maybe make them optional and specify what the defaul value is ?
>
Will do.

>
> > +- hsync-active: active state of the HSYNC signal, 0/1 for LOW/HIGH respectively.
> > +             (Not required for bus-type equal 6)
> > +- vsync-active: active state of the VSYNC signal, 0/1 for LOW/HIGH respectively.
> > +             (Not required for bus-type equal 6)
>
> If they're not required, they're optional, aren't they ? :)
>
Agreed.

> > +- pclk-sample: sample data on rising (1) or falling (0) edge of the pixel clock
> > +            signal. (Not required for bus-type equal 6)
>
> Why the pclk polarity is does not apply to BT.656 ?
>
No it should apply.

> > +- bus-type: data bus type. Possible values are:
> > +         5 - Parallel
> > +         6 - Bt.656
>
> Are we making this required, or do we expect this to be deduced
> depending on which other properties have been specified ? Sakari it
> seems you would like this to become a properties that has to be
> specified most of the times, right ? (I tend to agree with that FWIW),
> but does it impact retro-compatibility ?
>
Agreed can be deduced from other properties. But shall wait for Sakari
to comment.

Cheers,
Prabhakar

> > +
> >  Example:
> >
> >  &i2c0 {
> > --
> > 2.17.1
> >
Lad, Prabhakar Aug. 15, 2020, 10:34 a.m. UTC | #3
Hi Jacopo,

On Mon, Aug 3, 2020 at 12:39 PM Lad Prabhakar
<prabhakar.mahadev-lad.rj@bp.renesas.com> wrote:
>
> Document endpoint properties required for parallel interface
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> ---
>  .../devicetree/bindings/media/i2c/ov772x.txt     | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
>
I see you already have a patch for YAML conversion for OV772x binding
[1], if you plan to post a v2 would you be OK to pick these changes as
part of your conversion changes ?

[1] https://www.spinics.net/lists/linux-media/msg173201.html

Cheers,
Prabhakar

> diff --git a/Documentation/devicetree/bindings/media/i2c/ov772x.txt b/Documentation/devicetree/bindings/media/i2c/ov772x.txt
> index 0b3ede5b8e6a..1f4153484717 100644
> --- a/Documentation/devicetree/bindings/media/i2c/ov772x.txt
> +++ b/Documentation/devicetree/bindings/media/i2c/ov772x.txt
> @@ -21,6 +21,22 @@ subnode for its digital output video port, in accordance with the video
>  interface bindings defined in Documentation/devicetree/bindings/media/
>  video-interfaces.txt.
>
> +Endpoint node required properties for parallel connection are:
> +- remote-endpoint: a phandle to the bus receiver's endpoint node.
> +- bus-width: shall be set to <8> for 8 bits parallel bus
> +            or <10> for 10 bits parallel bus
> +- data-shift: shall be set to <2> for 8 bits parallel bus
> +             (lines 9:2 are used) or <0> for 10 bits parallel bus
> +- hsync-active: active state of the HSYNC signal, 0/1 for LOW/HIGH respectively.
> +               (Not required for bus-type equal 6)
> +- vsync-active: active state of the VSYNC signal, 0/1 for LOW/HIGH respectively.
> +               (Not required for bus-type equal 6)
> +- pclk-sample: sample data on rising (1) or falling (0) edge of the pixel clock
> +              signal. (Not required for bus-type equal 6)
> +- bus-type: data bus type. Possible values are:
> +           5 - Parallel
> +           6 - Bt.656
> +
>  Example:
>
>  &i2c0 {
> --
> 2.17.1
>
Jacopo Mondi Aug. 17, 2020, 8:11 a.m. UTC | #4
Hello Prabhakar,

On Sat, Aug 15, 2020 at 11:34:33AM +0100, Lad, Prabhakar wrote:
> Hi Jacopo,
>
> On Mon, Aug 3, 2020 at 12:39 PM Lad Prabhakar
> <prabhakar.mahadev-lad.rj@bp.renesas.com> wrote:
> >
> > Document endpoint properties required for parallel interface
> >
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > ---
> >  .../devicetree/bindings/media/i2c/ov772x.txt     | 16 ++++++++++++++++
> >  1 file changed, 16 insertions(+)
> >
> I see you already have a patch for YAML conversion for OV772x binding
> [1], if you plan to post a v2 would you be OK to pick these changes as
> part of your conversion changes ?

Sure thing, I'll add the following properties to the series!

Thanks
  j

>
> [1] https://www.spinics.net/lists/linux-media/msg173201.html
>
> Cheers,
> Prabhakar
>
> > diff --git a/Documentation/devicetree/bindings/media/i2c/ov772x.txt b/Documentation/devicetree/bindings/media/i2c/ov772x.txt
> > index 0b3ede5b8e6a..1f4153484717 100644
> > --- a/Documentation/devicetree/bindings/media/i2c/ov772x.txt
> > +++ b/Documentation/devicetree/bindings/media/i2c/ov772x.txt
> > @@ -21,6 +21,22 @@ subnode for its digital output video port, in accordance with the video
> >  interface bindings defined in Documentation/devicetree/bindings/media/
> >  video-interfaces.txt.
> >
> > +Endpoint node required properties for parallel connection are:
> > +- remote-endpoint: a phandle to the bus receiver's endpoint node.
> > +- bus-width: shall be set to <8> for 8 bits parallel bus
> > +            or <10> for 10 bits parallel bus
> > +- data-shift: shall be set to <2> for 8 bits parallel bus
> > +             (lines 9:2 are used) or <0> for 10 bits parallel bus
> > +- hsync-active: active state of the HSYNC signal, 0/1 for LOW/HIGH respectively.
> > +               (Not required for bus-type equal 6)
> > +- vsync-active: active state of the VSYNC signal, 0/1 for LOW/HIGH respectively.
> > +               (Not required for bus-type equal 6)
> > +- pclk-sample: sample data on rising (1) or falling (0) edge of the pixel clock
> > +              signal. (Not required for bus-type equal 6)
> > +- bus-type: data bus type. Possible values are:
> > +           5 - Parallel
> > +           6 - Bt.656
> > +
> >  Example:
> >
> >  &i2c0 {
> > --
> > 2.17.1
> >
Lad, Prabhakar Aug. 17, 2020, 12:01 p.m. UTC | #5
On Mon, Aug 17, 2020 at 9:07 AM Jacopo Mondi <jacopo@jmondi.org> wrote:
>
> Hello Prabhakar,
>
> On Sat, Aug 15, 2020 at 11:34:33AM +0100, Lad, Prabhakar wrote:
> > Hi Jacopo,
> >
> > On Mon, Aug 3, 2020 at 12:39 PM Lad Prabhakar
> > <prabhakar.mahadev-lad.rj@bp.renesas.com> wrote:
> > >
> > > Document endpoint properties required for parallel interface
> > >
> > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > > ---
> > >  .../devicetree/bindings/media/i2c/ov772x.txt     | 16 ++++++++++++++++
> > >  1 file changed, 16 insertions(+)
> > >
> > I see you already have a patch for YAML conversion for OV772x binding
> > [1], if you plan to post a v2 would you be OK to pick these changes as
> > part of your conversion changes ?
>
> Sure thing, I'll add the following properties to the series!
>
Thank you Jacopo. I'll get on with the v3 version of the series.

Cheers,
Prabhakar

> Thanks
>   j
>
> >
> > [1] https://www.spinics.net/lists/linux-media/msg173201.html
> >
> > Cheers,
> > Prabhakar
> >
> > > diff --git a/Documentation/devicetree/bindings/media/i2c/ov772x.txt b/Documentation/devicetree/bindings/media/i2c/ov772x.txt
> > > index 0b3ede5b8e6a..1f4153484717 100644
> > > --- a/Documentation/devicetree/bindings/media/i2c/ov772x.txt
> > > +++ b/Documentation/devicetree/bindings/media/i2c/ov772x.txt
> > > @@ -21,6 +21,22 @@ subnode for its digital output video port, in accordance with the video
> > >  interface bindings defined in Documentation/devicetree/bindings/media/
> > >  video-interfaces.txt.
> > >
> > > +Endpoint node required properties for parallel connection are:
> > > +- remote-endpoint: a phandle to the bus receiver's endpoint node.
> > > +- bus-width: shall be set to <8> for 8 bits parallel bus
> > > +            or <10> for 10 bits parallel bus
> > > +- data-shift: shall be set to <2> for 8 bits parallel bus
> > > +             (lines 9:2 are used) or <0> for 10 bits parallel bus
> > > +- hsync-active: active state of the HSYNC signal, 0/1 for LOW/HIGH respectively.
> > > +               (Not required for bus-type equal 6)
> > > +- vsync-active: active state of the VSYNC signal, 0/1 for LOW/HIGH respectively.
> > > +               (Not required for bus-type equal 6)
> > > +- pclk-sample: sample data on rising (1) or falling (0) edge of the pixel clock
> > > +              signal. (Not required for bus-type equal 6)
> > > +- bus-type: data bus type. Possible values are:
> > > +           5 - Parallel
> > > +           6 - Bt.656
> > > +
> > >  Example:
> > >
> > >  &i2c0 {
> > > --
> > > 2.17.1
> > >
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/media/i2c/ov772x.txt b/Documentation/devicetree/bindings/media/i2c/ov772x.txt
index 0b3ede5b8e6a..1f4153484717 100644
--- a/Documentation/devicetree/bindings/media/i2c/ov772x.txt
+++ b/Documentation/devicetree/bindings/media/i2c/ov772x.txt
@@ -21,6 +21,22 @@  subnode for its digital output video port, in accordance with the video
 interface bindings defined in Documentation/devicetree/bindings/media/
 video-interfaces.txt.
 
+Endpoint node required properties for parallel connection are:
+- remote-endpoint: a phandle to the bus receiver's endpoint node.
+- bus-width: shall be set to <8> for 8 bits parallel bus
+	     or <10> for 10 bits parallel bus
+- data-shift: shall be set to <2> for 8 bits parallel bus
+	      (lines 9:2 are used) or <0> for 10 bits parallel bus
+- hsync-active: active state of the HSYNC signal, 0/1 for LOW/HIGH respectively.
+		(Not required for bus-type equal 6)
+- vsync-active: active state of the VSYNC signal, 0/1 for LOW/HIGH respectively.
+		(Not required for bus-type equal 6)
+- pclk-sample: sample data on rising (1) or falling (0) edge of the pixel clock
+	       signal. (Not required for bus-type equal 6)
+- bus-type: data bus type. Possible values are:
+	    5 - Parallel
+	    6 - Bt.656
+
 Example:
 
 &i2c0 {