[PATCH] dt: bindings: Add support for CSI1 bus

[PATCH] dt: bindings: Add support for CSI1 bus

[Pavel Machek]

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From: Sakari Ailus <sakari.ailus@iki.fi>

In the vast majority of cases the bus type is known to the driver(s)
since a receiver or transmitter can only support a single one. There
are cases however where different options are possible.

Document the CSI1/CCP2 properties strobe_clk_inv and strobe_clock
properties. The former tells whether the strobe/clock signal is
inverted, while the latter signifies the clock or strobe mode.

Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>
Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

diff --git a/Documentation/devicetree/bindings/media/video-interfaces.txt b/Documentation/devicetree/bindings/media/video-interfaces.txt
index 9cd2a36..f0523f7 100644
--- a/Documentation/devicetree/bindings/media/video-interfaces.txt
+++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
@@ -76,6 +76,10 @@ Optional endpoint properties
   mode horizontal and vertical synchronization signals are provided to the
   slave device (data source) by the master device (data sink). In the master
   mode the data source device is also the source of the synchronization signals.
+- bus-type: data bus type. Possible values are:
+  0 - CSI2
+  1 - parallel / Bt656
+  2 - CCP2
 - bus-width: number of data lines actively used, valid for the parallel busses.
 - data-shift: on the parallel data busses, if bus-width is used to specify the
   number of data lines, data-shift can be used to specify which data lines are
@@ -110,9 +114,10 @@ Optional endpoint properties
   lane and followed by the data lanes in the same order as in data-lanes.
   Valid values are 0 (normal) and 1 (inverted). The length of the array
   should be the combined length of data-lanes and clock-lanes properties.
-  If the lane-polarities property is omitted, the value must be interpreted
-  as 0 (normal). This property is valid for serial busses only.
-
+- clock-inv: Clock or strobe signal inversion.
+  Possible values: 0 -- not inverted; 1 -- inverted
+- strobe: Whether the clock signal is used as clock or strobe. Used
+  with CCP2, for instance.
 
 Example
 -------


-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [PATCH] dt: bindings: Add support for CSI1 bus

[Sakari Ailus]

Hi Pavel,

On Wed, Dec 28, 2016 at 07:30:36PM +0100, Pavel Machek wrote:
> From: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> 
> In the vast majority of cases the bus type is known to the driver(s)
> since a receiver or transmitter can only support a single one. There
> are cases however where different options are possible.
> 
> Document the CSI1/CCP2 properties strobe_clk_inv and strobe_clock
> properties. The former tells whether the strobe/clock signal is
> inverted, while the latter signifies the clock or strobe mode.
> 
> Signed-off-by: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Signed-off-by: Pavel Machek <pavel-+ZI9xUNit7I@public.gmane.org>
> 
> diff --git a/Documentation/devicetree/bindings/media/video-interfaces.txt b/Documentation/devicetree/bindings/media/video-interfaces.txt
> index 9cd2a36..f0523f7 100644
> --- a/Documentation/devicetree/bindings/media/video-interfaces.txt
> +++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
> @@ -76,6 +76,10 @@ Optional endpoint properties
>    mode horizontal and vertical synchronization signals are provided to the
>    slave device (data source) by the master device (data sink). In the master
>    mode the data source device is also the source of the synchronization signals.
> +- bus-type: data bus type. Possible values are:
> +  0 - CSI2
> +  1 - parallel / Bt656
> +  2 - CCP2

I wonder if we should make a difference between CCP2 and CSI-1 here, as it
may make a difference in hardware configuration. The next patch does
recognise that difference, so it should be present here as well.

Perhaps 2 - CSI1; 3 - CCP2. What do you think?

>  - bus-width: number of data lines actively used, valid for the parallel busses.
>  - data-shift: on the parallel data busses, if bus-width is used to specify the
>    number of data lines, data-shift can be used to specify which data lines are
> @@ -110,9 +114,10 @@ Optional endpoint properties
>    lane and followed by the data lanes in the same order as in data-lanes.
>    Valid values are 0 (normal) and 1 (inverted). The length of the array
>    should be the combined length of data-lanes and clock-lanes properties.
> -  If the lane-polarities property is omitted, the value must be interpreted
> -  as 0 (normal). This property is valid for serial busses only.
> -
> +- clock-inv: Clock or strobe signal inversion.
> +  Possible values: 0 -- not inverted; 1 -- inverted
> +- strobe: Whether the clock signal is used as clock or strobe. Used
> +  with CCP2, for instance.
>  
>  Example
>  -------
> 
> 



-- 
Kind regards,

Sakari Ailus
e-mail: sakari.ailus-X3B1VOXEql0@public.gmane.org	XMPP: sailus-PCDdDYkjdNMDXYZnReoRVg@public.gmane.org
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Re: [PATCH] dt: bindings: Add support for CSI1 bus

[Rob Herring]

On Wed, Dec 28, 2016 at 07:30:36PM +0100, Pavel Machek wrote:
> From: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> 
> In the vast majority of cases the bus type is known to the driver(s)
> since a receiver or transmitter can only support a single one. There
> are cases however where different options are possible.

What cases specifically?

> Document the CSI1/CCP2 properties strobe_clk_inv and strobe_clock
> properties. The former tells whether the strobe/clock signal is
> inverted, while the latter signifies the clock or strobe mode.
> 
> Signed-off-by: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Signed-off-by: Pavel Machek <pavel-+ZI9xUNit7I@public.gmane.org>
> 
> diff --git a/Documentation/devicetree/bindings/media/video-interfaces.txt b/Documentation/devicetree/bindings/media/video-interfaces.txt
> index 9cd2a36..f0523f7 100644
> --- a/Documentation/devicetree/bindings/media/video-interfaces.txt
> +++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
> @@ -76,6 +76,10 @@ Optional endpoint properties
>    mode horizontal and vertical synchronization signals are provided to the
>    slave device (data source) by the master device (data sink). In the master
>    mode the data source device is also the source of the synchronization signals.
> +- bus-type: data bus type. Possible values are:
> +  0 - CSI2

As in MIPI CSI2?

> +  1 - parallel / Bt656
> +  2 - CCP2
>  - bus-width: number of data lines actively used, valid for the parallel busses.
>  - data-shift: on the parallel data busses, if bus-width is used to specify the
>    number of data lines, data-shift can be used to specify which data lines are
> @@ -110,9 +114,10 @@ Optional endpoint properties
>    lane and followed by the data lanes in the same order as in data-lanes.
>    Valid values are 0 (normal) and 1 (inverted). The length of the array
>    should be the combined length of data-lanes and clock-lanes properties.
> -  If the lane-polarities property is omitted, the value must be interpreted
> -  as 0 (normal). This property is valid for serial busses only.

Why is this removed?

> -
> +- clock-inv: Clock or strobe signal inversion.
> +  Possible values: 0 -- not inverted; 1 -- inverted

"invert" assumes I know what is normal and I do not. Define what is 
"normal" and name the property the opposite of that. If normal is data 
shifted on clock rising edge, then call the the property 
"clock-shift-falling-edge" for example..

> +- strobe: Whether the clock signal is used as clock or strobe. Used
> +  with CCP2, for instance.
>  
>  Example
>  -------
> 
> 
> -- 
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html


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Re: [PATCH] dt: bindings: Add support for CSI1 bus

[Sakari Ailus]

Hi Rob,

Thanks for the review.

On Tue, Jan 03, 2017 at 02:38:54PM -0600, Rob Herring wrote:
> On Wed, Dec 28, 2016 at 07:30:36PM +0100, Pavel Machek wrote:
> > From: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> > 
> > In the vast majority of cases the bus type is known to the driver(s)
> > since a receiver or transmitter can only support a single one. There
> > are cases however where different options are possible.
> 
> What cases specifically?

The existing V4L2 OF support tries to figure out the bus type and parse the
bus parameters based on that. This does not scale too well as there are
multiple serial busses that share common properties.

Some hardware also supports multiple types of busses on the same interfaces.

> 
> > Document the CSI1/CCP2 properties strobe_clk_inv and strobe_clock
> > properties. The former tells whether the strobe/clock signal is
> > inverted, while the latter signifies the clock or strobe mode.
> > 
> > Signed-off-by: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> > Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> > Signed-off-by: Pavel Machek <pavel-+ZI9xUNit7I@public.gmane.org>
> > 
> > diff --git a/Documentation/devicetree/bindings/media/video-interfaces.txt b/Documentation/devicetree/bindings/media/video-interfaces.txt
> > index 9cd2a36..f0523f7 100644
> > --- a/Documentation/devicetree/bindings/media/video-interfaces.txt
> > +++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
> > @@ -76,6 +76,10 @@ Optional endpoint properties
> >    mode horizontal and vertical synchronization signals are provided to the
> >    slave device (data source) by the master device (data sink). In the master
> >    mode the data source device is also the source of the synchronization signals.
> > +- bus-type: data bus type. Possible values are:
> > +  0 - CSI2
> 
> As in MIPI CSI2?

Yeah, I guess it'd make sense to make this explicit.

> 
> > +  1 - parallel / Bt656
> > +  2 - CCP2
> >  - bus-width: number of data lines actively used, valid for the parallel busses.
> >  - data-shift: on the parallel data busses, if bus-width is used to specify the
> >    number of data lines, data-shift can be used to specify which data lines are
> > @@ -110,9 +114,10 @@ Optional endpoint properties
> >    lane and followed by the data lanes in the same order as in data-lanes.
> >    Valid values are 0 (normal) and 1 (inverted). The length of the array
> >    should be the combined length of data-lanes and clock-lanes properties.
> > -  If the lane-polarities property is omitted, the value must be interpreted
> > -  as 0 (normal). This property is valid for serial busses only.
> 
> Why is this removed?

Must have been by mistake. :-)

> 
> > -
> > +- clock-inv: Clock or strobe signal inversion.
> > +  Possible values: 0 -- not inverted; 1 -- inverted
> 
> "invert" assumes I know what is normal and I do not. Define what is 
> "normal" and name the property the opposite of that. If normal is data 
> shifted on clock rising edge, then call the the property 
> "clock-shift-falling-edge" for example..

The hardware documentation says this is the "strobe/clock inversion control
signal". I'm not entirely sure whether this is just signal polarity (it's a
differential signal) or inversion of an internal signal of the CCP2 block.

It might make sense to make this a private property for the OMAP 3 ISP
instead. If it's seen elsewhere, then think about it again. I doubt it
would, as CCP2 is an old bus that's used on Nokia N9, N950 and N900.

As strobe is included, I'd add that to the name. Say, "ti,clock-strobe-inv".

> 
> > +- strobe: Whether the clock signal is used as clock or strobe. Used
> > +  with CCP2, for instance.
> >  
> >  Example
> >  -------
> > 
> > 

-- 
Kind regards,

Sakari Ailus
e-mail: sakari.ailus-X3B1VOXEql0@public.gmane.org	XMPP: sailus-PCDdDYkjdNMDXYZnReoRVg@public.gmane.org
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Re: [PATCH] dt: bindings: Add support for CSI1 bus

[Pavel Machek]

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On Mon 2017-01-02 09:00:10, Sakari Ailus wrote:
> Hi Pavel,
> 
> On Wed, Dec 28, 2016 at 07:30:36PM +0100, Pavel Machek wrote:
> > From: Sakari Ailus <sakari.ailus@iki.fi>
> > 
> > In the vast majority of cases the bus type is known to the driver(s)
> > since a receiver or transmitter can only support a single one. There
> > are cases however where different options are possible.
> > 
> > Document the CSI1/CCP2 properties strobe_clk_inv and strobe_clock
> > properties. The former tells whether the strobe/clock signal is
> > inverted, while the latter signifies the clock or strobe mode.
> > 
> > Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>
> > Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
> > Signed-off-by: Pavel Machek <pavel@ucw.cz>
> > 
> > diff --git a/Documentation/devicetree/bindings/media/video-interfaces.txt b/Documentation/devicetree/bindings/media/video-interfaces.txt
> > index 9cd2a36..f0523f7 100644
> > --- a/Documentation/devicetree/bindings/media/video-interfaces.txt
> > +++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
> > @@ -76,6 +76,10 @@ Optional endpoint properties
> >    mode horizontal and vertical synchronization signals are provided to the
> >    slave device (data source) by the master device (data sink). In the master
> >    mode the data source device is also the source of the synchronization signals.
> > +- bus-type: data bus type. Possible values are:
> > +  0 - CSI2
> > +  1 - parallel / Bt656
> > +  2 - CCP2
> 
> I wonder if we should make a difference between CCP2 and CSI-1 here, as it
> may make a difference in hardware configuration. The next patch does
> recognise that difference, so it should be present here as well.
> 
> Perhaps 2 - CSI1; 3 - CCP2. What do you think?

Me, think..? Nah. :-).

Well, you have way more experience here, and yes, based on future
patches, this makes sense.

Thanks,								Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [PATCH] dt: bindings: Add support for CSI1 bus

[Pavel Machek]

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Hi!

> Thanks for the review.
> 
> On Tue, Jan 03, 2017 at 02:38:54PM -0600, Rob Herring wrote:
> > On Wed, Dec 28, 2016 at 07:30:36PM +0100, Pavel Machek wrote:
> > > From: Sakari Ailus <sakari.ailus@iki.fi>
> > > 
> > > In the vast majority of cases the bus type is known to the driver(s)
> > > since a receiver or transmitter can only support a single one. There
> > > are cases however where different options are possible.
> > 
> > What cases specifically?
> 
> The existing V4L2 OF support tries to figure out the bus type and parse the
> bus parameters based on that. This does not scale too well as there are
> multiple serial busses that share common properties.
> 
> Some hardware also supports multiple types of busses on the same interfaces.

Ok, I'll include that in the changelog.

> > As in MIPI CSI2?
> 
> Yeah, I guess it'd make sense to make this explicit.

Ok.

> > >    should be the combined length of data-lanes and clock-lanes properties.
> > > -  If the lane-polarities property is omitted, the value must be interpreted
> > > -  as 0 (normal). This property is valid for serial busses only.
> > 
> > Why is this removed?
> 
> Must have been by mistake. :-)

Fixed.

> > > -
> > > +- clock-inv: Clock or strobe signal inversion.
> > > +  Possible values: 0 -- not inverted; 1 -- inverted
> > 
> > "invert" assumes I know what is normal and I do not. Define what is 
> > "normal" and name the property the opposite of that. If normal is data 
> > shifted on clock rising edge, then call the the property 
> > "clock-shift-falling-edge" for example..
> 
> The hardware documentation says this is the "strobe/clock inversion control
> signal". I'm not entirely sure whether this is just signal polarity (it's a
> differential signal) or inversion of an internal signal of the CCP2 block.
> 
> It might make sense to make this a private property for the OMAP 3 ISP
> instead. If it's seen elsewhere, then think about it again. I doubt it
> would, as CCP2 is an old bus that's used on Nokia N9, N950 and N900.
> 
> As strobe is included, I'd add that to the name. Say,
> "ti,clock-strobe-inv".

Hmm. N900 does not use inversion. Would it make sense to simply
hardcode it to "not-inverted" for now?

Device tree changes are PITA :-(.
									Pavel

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [PATCH] dt: bindings: Add support for CSI1 bus

[Sakari Ailus]

Hi Pavel,

On Wed, Jan 11, 2017 at 11:06:48PM +0100, Pavel Machek wrote:
> > > > +- clock-inv: Clock or strobe signal inversion.
> > > > +  Possible values: 0 -- not inverted; 1 -- inverted
> > > 
> > > "invert" assumes I know what is normal and I do not. Define what is 
> > > "normal" and name the property the opposite of that. If normal is data 
> > > shifted on clock rising edge, then call the the property 
> > > "clock-shift-falling-edge" for example..
> > 
> > The hardware documentation says this is the "strobe/clock inversion control
> > signal". I'm not entirely sure whether this is just signal polarity (it's a
> > differential signal) or inversion of an internal signal of the CCP2 block.
> > 
> > It might make sense to make this a private property for the OMAP 3 ISP
> > instead. If it's seen elsewhere, then think about it again. I doubt it
> > would, as CCP2 is an old bus that's used on Nokia N9, N950 and N900.
> > 
> > As strobe is included, I'd add that to the name. Say,
> > "ti,clock-strobe-inv".
> 
> Hmm. N900 does not use inversion. Would it make sense to simply
> hardcode it to "not-inverted" for now?
> 
> Device tree changes are PITA :-(.

I can't remember what's used for the N9 secondary camera. As you said, we
can always add it if needed though. So works for me.

-- 
Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

[PATCHv2] dt: bindings: Add support for CSI1 bus

[Pavel Machek]

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From: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>

In the vast majority of cases the bus type is known to the driver(s)
since a receiver or transmitter can only support a single one. There
are cases however where different options are possible.

The existing V4L2 OF support tries to figure out the bus type and
parse the bus parameters based on that. This does not scale too well
as there are multiple serial busses that share common properties.

Some hardware also supports multiple types of busses on the same
interfaces.

Document the CSI1/CCP2 property strobe. It signifies the clock or
strobe mode.
 
Signed-off-by: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Signed-off-by: Pavel Machek <pavel-+ZI9xUNit7I@public.gmane.org>

diff --git a/Documentation/devicetree/bindings/media/video-interfaces.txt b/Documentation/devicetree/bindings/media/video-interfaces.txt
index 9cd2a36..08c4498 100644
--- a/Documentation/devicetree/bindings/media/video-interfaces.txt
+++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
@@ -76,6 +76,11 @@ Optional endpoint properties
   mode horizontal and vertical synchronization signals are provided to the
   slave device (data source) by the master device (data sink). In the master
   mode the data source device is also the source of the synchronization signals.
+- bus-type: data bus type. Possible values are:
+  0 - MIPI CSI2
+  1 - parallel / Bt656
+  2 - MIPI CSI1
+  3 - CCP2
 - bus-width: number of data lines actively used, valid for the parallel busses.
 - data-shift: on the parallel data busses, if bus-width is used to specify the
   number of data lines, data-shift can be used to specify which data lines are
@@ -112,7 +117,8 @@ Optional endpoint properties
   should be the combined length of data-lanes and clock-lanes properties.
   If the lane-polarities property is omitted, the value must be interpreted
   as 0 (normal). This property is valid for serial busses only.
-
+- strobe: Whether the clock signal is used as clock or strobe. Used
+  with CCP2, for instance.
 
 Example
 -------


-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [PATCHv2] dt: bindings: Add support for CSI1 bus

[Sebastian Reichel]

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Hi,

On Wed, Jan 11, 2017 at 11:53:35PM +0100, Pavel Machek wrote:
> From: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> 
> In the vast majority of cases the bus type is known to the driver(s)
> since a receiver or transmitter can only support a single one. There
> are cases however where different options are possible.
> 
> The existing V4L2 OF support tries to figure out the bus type and
> parse the bus parameters based on that. This does not scale too well
> as there are multiple serial busses that share common properties.
> 
> Some hardware also supports multiple types of busses on the same
> interfaces.
> 
> Document the CSI1/CCP2 property strobe. It signifies the clock or
> strobe mode.
>  
> Signed-off-by: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Signed-off-by: Pavel Machek <pavel-+ZI9xUNit7I@public.gmane.org>
> 
> diff --git a/Documentation/devicetree/bindings/media/video-interfaces.txt b/Documentation/devicetree/bindings/media/video-interfaces.txt
> index 9cd2a36..08c4498 100644
> --- a/Documentation/devicetree/bindings/media/video-interfaces.txt
> +++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
> @@ -76,6 +76,11 @@ Optional endpoint properties
>    mode horizontal and vertical synchronization signals are provided to the
>    slave device (data source) by the master device (data sink). In the master
>    mode the data source device is also the source of the synchronization signals.
> +- bus-type: data bus type. Possible values are:
> +  0 - MIPI CSI2
> +  1 - parallel / Bt656
> +  2 - MIPI CSI1
> +  3 - CCP2
>  - bus-width: number of data lines actively used, valid for the parallel busses.
>  - data-shift: on the parallel data busses, if bus-width is used to specify the
>    number of data lines, data-shift can be used to specify which data lines are
> @@ -112,7 +117,8 @@ Optional endpoint properties
>    should be the combined length of data-lanes and clock-lanes properties.
>    If the lane-polarities property is omitted, the value must be interpreted
>    as 0 (normal). This property is valid for serial busses only.
> -
> +- strobe: Whether the clock signal is used as clock or strobe. Used
> +  with CCP2, for instance.
>  
>  Example
>  -------
> 
> 

Reviewed-By: Sebastian Reichel <sre-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>

-- Sebastian

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

Re: [PATCHv2] dt: bindings: Add support for CSI1 bus

[Baruch Siach]

Hi Pavel,

On Wed, Jan 11, 2017 at 11:53:35PM +0100, Pavel Machek wrote:
> From: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> 
> In the vast majority of cases the bus type is known to the driver(s)
> since a receiver or transmitter can only support a single one. There
> are cases however where different options are possible.
> 
> The existing V4L2 OF support tries to figure out the bus type and
> parse the bus parameters based on that. This does not scale too well
> as there are multiple serial busses that share common properties.
> 
> Some hardware also supports multiple types of busses on the same
> interfaces.
> 
> Document the CSI1/CCP2 property strobe. It signifies the clock or
> strobe mode.
>  
> Signed-off-by: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Signed-off-by: Pavel Machek <pavel-+ZI9xUNit7I@public.gmane.org>
> 
> diff --git a/Documentation/devicetree/bindings/media/video-interfaces.txt b/Documentation/devicetree/bindings/media/video-interfaces.txt
> index 9cd2a36..08c4498 100644
> --- a/Documentation/devicetree/bindings/media/video-interfaces.txt
> +++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
> @@ -76,6 +76,11 @@ Optional endpoint properties
>    mode horizontal and vertical synchronization signals are provided to the
>    slave device (data source) by the master device (data sink). In the master
>    mode the data source device is also the source of the synchronization signals.
> +- bus-type: data bus type. Possible values are:
> +  0 - MIPI CSI2
> +  1 - parallel / Bt656

Why not have separate values for parallel and BT.656?

baruch

> +  2 - MIPI CSI1
> +  3 - CCP2
>  - bus-width: number of data lines actively used, valid for the parallel busses.
>  - data-shift: on the parallel data busses, if bus-width is used to specify the
>    number of data lines, data-shift can be used to specify which data lines are
> @@ -112,7 +117,8 @@ Optional endpoint properties
>    should be the combined length of data-lanes and clock-lanes properties.
>    If the lane-polarities property is omitted, the value must be interpreted
>    as 0 (normal). This property is valid for serial busses only.
> -
> +- strobe: Whether the clock signal is used as clock or strobe. Used
> +  with CCP2, for instance.
>  
>  Example
>  -------

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Re: [PATCHv2] dt: bindings: Add support for CSI1 bus

[Sakari Ailus]

Hi Baruch,

On Thu, Jan 12, 2017 at 02:06:03PM +0200, Baruch Siach wrote:
> Hi Pavel,
> 
> On Wed, Jan 11, 2017 at 11:53:35PM +0100, Pavel Machek wrote:
> > From: Sakari Ailus <sakari.ailus@iki.fi>
> > 
> > In the vast majority of cases the bus type is known to the driver(s)
> > since a receiver or transmitter can only support a single one. There
> > are cases however where different options are possible.
> > 
> > The existing V4L2 OF support tries to figure out the bus type and
> > parse the bus parameters based on that. This does not scale too well
> > as there are multiple serial busses that share common properties.
> > 
> > Some hardware also supports multiple types of busses on the same
> > interfaces.
> > 
> > Document the CSI1/CCP2 property strobe. It signifies the clock or
> > strobe mode.
> >  
> > Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>
> > Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
> > Signed-off-by: Pavel Machek <pavel@ucw.cz>
> > 
> > diff --git a/Documentation/devicetree/bindings/media/video-interfaces.txt b/Documentation/devicetree/bindings/media/video-interfaces.txt
> > index 9cd2a36..08c4498 100644
> > --- a/Documentation/devicetree/bindings/media/video-interfaces.txt
> > +++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
> > @@ -76,6 +76,11 @@ Optional endpoint properties
> >    mode horizontal and vertical synchronization signals are provided to the
> >    slave device (data source) by the master device (data sink). In the master
> >    mode the data source device is also the source of the synchronization signals.
> > +- bus-type: data bus type. Possible values are:
> > +  0 - MIPI CSI2
> > +  1 - parallel / Bt656
> 
> Why not have separate values for parallel and BT.656?

The current implementation of V4L2 OF support digs the information from
other properties (hsync-active, vsync-active and field-even-active). If any
of them are present, the bus is considered to be a regular parallel bus ---
the Bt.656 has no such signals.

CSI-2 bus is assumed if CSI-2 specific properties can be found. However,
explicit bus type is needed as the type of the bus isn't anymore implicitly
determinable with the addition of CSI-1 and CCP2 busses: they use the same
properties.

-- 
Kind regards,

Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

Re: [PATCHv2] dt: bindings: Add support for CSI1 bus

[Sakari Ailus]

Hi Pavel,

On Wed, Jan 11, 2017 at 11:53:35PM +0100, Pavel Machek wrote:
> From: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> 
> In the vast majority of cases the bus type is known to the driver(s)
> since a receiver or transmitter can only support a single one. There
> are cases however where different options are possible.
> 
> The existing V4L2 OF support tries to figure out the bus type and
> parse the bus parameters based on that. This does not scale too well
> as there are multiple serial busses that share common properties.
> 
> Some hardware also supports multiple types of busses on the same
> interfaces.
> 
> Document the CSI1/CCP2 property strobe. It signifies the clock or
> strobe mode.
>  
> Signed-off-by: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Signed-off-by: Pavel Machek <pavel-+ZI9xUNit7I@public.gmane.org>
> 
> diff --git a/Documentation/devicetree/bindings/media/video-interfaces.txt b/Documentation/devicetree/bindings/media/video-interfaces.txt
> index 9cd2a36..08c4498 100644
> --- a/Documentation/devicetree/bindings/media/video-interfaces.txt
> +++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
> @@ -76,6 +76,11 @@ Optional endpoint properties
>    mode horizontal and vertical synchronization signals are provided to the
>    slave device (data source) by the master device (data sink). In the master
>    mode the data source device is also the source of the synchronization signals.
> +- bus-type: data bus type. Possible values are:
> +  0 - MIPI CSI2
> +  1 - parallel / Bt656
> +  2 - MIPI CSI1
> +  3 - CCP2

Actually, thinking about this again --- we only need to explictly specify
busses if we're dealing with either CCP2 or CSI-1. The vast majority of the
actual busses are and continue to be CSI-2 or either parallel or Bt.656. As
they can be implicitly detected, we would have an option to just drop values
0 and 1 from above, i.e. only leave CSI-1 and CCP2. For now, specifying
CSI-2 or parallel / Bt.656 adds no value as the old DT binaries without
bus-type will need to be supported anyway.

>  - bus-width: number of data lines actively used, valid for the parallel busses.
>  - data-shift: on the parallel data busses, if bus-width is used to specify the
>    number of data lines, data-shift can be used to specify which data lines are
> @@ -112,7 +117,8 @@ Optional endpoint properties
>    should be the combined length of data-lanes and clock-lanes properties.
>    If the lane-polarities property is omitted, the value must be interpreted
>    as 0 (normal). This property is valid for serial busses only.
> -
> +- strobe: Whether the clock signal is used as clock or strobe. Used
> +  with CCP2, for instance.

How about the "ti,strobe-clock-inv" I proposed? No-one seems to know what
this really truly means... or just drop it if it's not really needed.

-- 
Cheers,

Sakari Ailus
e-mail: sakari.ailus-X3B1VOXEql0@public.gmane.org	XMPP: sailus-PCDdDYkjdNMDXYZnReoRVg@public.gmane.org
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Re: [PATCHv2] dt: bindings: Add support for CSI1 bus

[Ivaylo Dimitrov]

Hi,

On 19.01.2017 23:49, Sakari Ailus wrote:
> Hi Pavel,
>
> On Wed, Jan 11, 2017 at 11:53:35PM +0100, Pavel Machek wrote:
>> From: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
>>
>> In the vast majority of cases the bus type is known to the driver(s)
>> since a receiver or transmitter can only support a single one. There
>> are cases however where different options are possible.
>>
>> The existing V4L2 OF support tries to figure out the bus type and
>> parse the bus parameters based on that. This does not scale too well
>> as there are multiple serial busses that share common properties.
>>
>> Some hardware also supports multiple types of busses on the same
>> interfaces.
>>
>> Document the CSI1/CCP2 property strobe. It signifies the clock or
>> strobe mode.
>>
>> Signed-off-by: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
>> Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
>> Signed-off-by: Pavel Machek <pavel-+ZI9xUNit7I@public.gmane.org>
>>
>> diff --git a/Documentation/devicetree/bindings/media/video-interfaces.txt b/Documentation/devicetree/bindings/media/video-interfaces.txt
>> index 9cd2a36..08c4498 100644
>> --- a/Documentation/devicetree/bindings/media/video-interfaces.txt
>> +++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
>> @@ -76,6 +76,11 @@ Optional endpoint properties
>>    mode horizontal and vertical synchronization signals are provided to the
>>    slave device (data source) by the master device (data sink). In the master
>>    mode the data source device is also the source of the synchronization signals.
>> +- bus-type: data bus type. Possible values are:
>> +  0 - MIPI CSI2
>> +  1 - parallel / Bt656
>> +  2 - MIPI CSI1
>> +  3 - CCP2
>
> Actually, thinking about this again --- we only need to explictly specify
> busses if we're dealing with either CCP2 or CSI-1. The vast majority of the
> actual busses are and continue to be CSI-2 or either parallel or Bt.656. As
> they can be implicitly detected, we would have an option to just drop values
> 0 and 1 from above, i.e. only leave CSI-1 and CCP2. For now, specifying
> CSI-2 or parallel / Bt.656 adds no value as the old DT binaries without
> bus-type will need to be supported anyway.
>
>>  - bus-width: number of data lines actively used, valid for the parallel busses.
>>  - data-shift: on the parallel data busses, if bus-width is used to specify the
>>    number of data lines, data-shift can be used to specify which data lines are
>> @@ -112,7 +117,8 @@ Optional endpoint properties
>>    should be the combined length of data-lanes and clock-lanes properties.
>>    If the lane-polarities property is omitted, the value must be interpreted
>>    as 0 (normal). This property is valid for serial busses only.
>> -
>> +- strobe: Whether the clock signal is used as clock or strobe. Used
>> +  with CCP2, for instance.
>
> How about the "ti,strobe-clock-inv" I proposed? No-one seems to know what
> this really truly means... or just drop it if it's not really needed.
>

Not really :), see 
https://www.spinics.net/lists/linux-media/msg99802.html and 
https://www.spinics.net/lists/linux-media/msg99800.html

"clock/strobe", and "strobe-inv" are two distinct properties, see 
CSI1B_CTRL description in OMAP TRM. BTW there is another property that 
is needed for both n900 cameras to operate correctly (VP_CLK_POL, bit 12 
from the same reg), but that can be added later on when we have the 
other bits in place.

Ivo
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Re: [PATCHv2] dt: bindings: Add support for CSI1 bus

[Sakari Ailus]

Hi Ivaylo,

On Fri, Jan 20, 2017 at 09:59:13AM +0200, Ivaylo Dimitrov wrote:
> Hi,
> 
> On 19.01.2017 23:49, Sakari Ailus wrote:
> >Hi Pavel,
> >
> >On Wed, Jan 11, 2017 at 11:53:35PM +0100, Pavel Machek wrote:
> >>From: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> >>
> >>In the vast majority of cases the bus type is known to the driver(s)
> >>since a receiver or transmitter can only support a single one. There
> >>are cases however where different options are possible.
> >>
> >>The existing V4L2 OF support tries to figure out the bus type and
> >>parse the bus parameters based on that. This does not scale too well
> >>as there are multiple serial busses that share common properties.
> >>
> >>Some hardware also supports multiple types of busses on the same
> >>interfaces.
> >>
> >>Document the CSI1/CCP2 property strobe. It signifies the clock or
> >>strobe mode.
> >>
> >>Signed-off-by: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> >>Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> >>Signed-off-by: Pavel Machek <pavel-+ZI9xUNit7I@public.gmane.org>
> >>
> >>diff --git a/Documentation/devicetree/bindings/media/video-interfaces.txt b/Documentation/devicetree/bindings/media/video-interfaces.txt
> >>index 9cd2a36..08c4498 100644
> >>--- a/Documentation/devicetree/bindings/media/video-interfaces.txt
> >>+++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
> >>@@ -76,6 +76,11 @@ Optional endpoint properties
> >>   mode horizontal and vertical synchronization signals are provided to the
> >>   slave device (data source) by the master device (data sink). In the master
> >>   mode the data source device is also the source of the synchronization signals.
> >>+- bus-type: data bus type. Possible values are:
> >>+  0 - MIPI CSI2
> >>+  1 - parallel / Bt656
> >>+  2 - MIPI CSI1
> >>+  3 - CCP2
> >
> >Actually, thinking about this again --- we only need to explictly specify
> >busses if we're dealing with either CCP2 or CSI-1. The vast majority of the
> >actual busses are and continue to be CSI-2 or either parallel or Bt.656. As
> >they can be implicitly detected, we would have an option to just drop values
> >0 and 1 from above, i.e. only leave CSI-1 and CCP2. For now, specifying
> >CSI-2 or parallel / Bt.656 adds no value as the old DT binaries without
> >bus-type will need to be supported anyway.
> >
> >> - bus-width: number of data lines actively used, valid for the parallel busses.
> >> - data-shift: on the parallel data busses, if bus-width is used to specify the
> >>   number of data lines, data-shift can be used to specify which data lines are
> >>@@ -112,7 +117,8 @@ Optional endpoint properties
> >>   should be the combined length of data-lanes and clock-lanes properties.
> >>   If the lane-polarities property is omitted, the value must be interpreted
> >>   as 0 (normal). This property is valid for serial busses only.
> >>-
> >>+- strobe: Whether the clock signal is used as clock or strobe. Used
> >>+  with CCP2, for instance.
> >
> >How about the "ti,strobe-clock-inv" I proposed? No-one seems to know what
> >this really truly means... or just drop it if it's not really needed.
> >
> 
> Not really :), see https://www.spinics.net/lists/linux-media/msg99802.html
> and https://www.spinics.net/lists/linux-media/msg99800.html
> 
> "clock/strobe", and "strobe-inv" are two distinct properties, see CSI1B_CTRL
> description in OMAP TRM. BTW there is another property that is needed for
> both n900 cameras to operate correctly (VP_CLK_POL, bit 12 from the same
> reg), but that can be added later on when we have the other bits in place.

Oh, indeed, my mistake. Please ignore that comment.

-- 
Sakari Ailus
e-mail: sakari.ailus-X3B1VOXEql0@public.gmane.org	XMPP: sailus-PCDdDYkjdNMDXYZnReoRVg@public.gmane.org
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Re: [PATCHv2] dt: bindings: Add support for CSI1 bus

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 2481 bytes --]

Hi!

> > --- a/Documentation/devicetree/bindings/media/video-interfaces.txt
> > +++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
> > @@ -76,6 +76,11 @@ Optional endpoint properties
> >    mode horizontal and vertical synchronization signals are provided to the
> >    slave device (data source) by the master device (data sink). In the master
> >    mode the data source device is also the source of the synchronization signals.
> > +- bus-type: data bus type. Possible values are:
> > +  0 - MIPI CSI2
> > +  1 - parallel / Bt656
> > +  2 - MIPI CSI1
> > +  3 - CCP2
> 
> Actually, thinking about this again --- we only need to explictly specify
> busses if we're dealing with either CCP2 or CSI-1. The vast majority of the
> actual busses are and continue to be CSI-2 or either parallel or Bt.656. As
> they can be implicitly detected, we would have an option to just drop values
> 0 and 1 from above, i.e. only leave CSI-1 and CCP2. For now, specifying
> CSI-2 or parallel / Bt.656 adds no value as the old DT binaries without
> bus-type will need to be supported anyway.

Hmm. "Just deleting the others" may be a bit confusing... but what
about this? It explains what we can autodetect.

Best regards,
								Pavel

diff --git a/Documentation/devicetree/bindings/media/video-interfaces.txt b/Documentation/devicetree/bindings/media/video-interfaces.txt
index 08c4498..d54093b 100644
--- a/Documentation/devicetree/bindings/media/video-interfaces.txt
+++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
@@ -77,10 +77,10 @@ Optional endpoint properties
   slave device (data source) by the master device (data sink). In the master
   mode the data source device is also the source of the synchronization signals.
 - bus-type: data bus type. Possible values are:
-  0 - MIPI CSI2
-  1 - parallel / Bt656
-  2 - MIPI CSI1
-  3 - CCP2
+  0 - autodetect based on other properties (MIPI CSI2, parallel, Bt656)
+  1 - MIPI CSI1
+  2 - CCP2
+  Autodetection is default, and bus-type property may be omitted in that case.
 - bus-width: number of data lines actively used, valid for the parallel busses.
 - data-shift: on the parallel data busses, if bus-width is used to specify the
   number of data lines, data-shift can be used to specify which data lines are


-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

[-- Attachment #2: Digital signature --]
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Re: [PATCHv2] dt: bindings: Add support for CSI1 bus

[Sakari Ailus]

Hi Pavel,

On Fri, Feb 03, 2017 at 12:50:45PM +0100, Pavel Machek wrote:
> Hi!
> 
> > > --- a/Documentation/devicetree/bindings/media/video-interfaces.txt
> > > +++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
> > > @@ -76,6 +76,11 @@ Optional endpoint properties
> > >    mode horizontal and vertical synchronization signals are provided to the
> > >    slave device (data source) by the master device (data sink). In the master
> > >    mode the data source device is also the source of the synchronization signals.
> > > +- bus-type: data bus type. Possible values are:
> > > +  0 - MIPI CSI2
> > > +  1 - parallel / Bt656
> > > +  2 - MIPI CSI1
> > > +  3 - CCP2
> > 
> > Actually, thinking about this again --- we only need to explictly specify
> > busses if we're dealing with either CCP2 or CSI-1. The vast majority of the
> > actual busses are and continue to be CSI-2 or either parallel or Bt.656. As
> > they can be implicitly detected, we would have an option to just drop values
> > 0 and 1 from above, i.e. only leave CSI-1 and CCP2. For now, specifying
> > CSI-2 or parallel / Bt.656 adds no value as the old DT binaries without
> > bus-type will need to be supported anyway.
> 
> Hmm. "Just deleting the others" may be a bit confusing... but what
> about this? It explains what we can autodetect.
> 
> Best regards,
> 								Pavel
> 
> diff --git a/Documentation/devicetree/bindings/media/video-interfaces.txt b/Documentation/devicetree/bindings/media/video-interfaces.txt
> index 08c4498..d54093b 100644
> --- a/Documentation/devicetree/bindings/media/video-interfaces.txt
> +++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
> @@ -77,10 +77,10 @@ Optional endpoint properties
>    slave device (data source) by the master device (data sink). In the master
>    mode the data source device is also the source of the synchronization signals.
>  - bus-type: data bus type. Possible values are:
> -  0 - MIPI CSI2
> -  1 - parallel / Bt656
> -  2 - MIPI CSI1
> -  3 - CCP2
> +  0 - autodetect based on other properties (MIPI CSI2, parallel, Bt656)

In the meantime, I also realised that we need to separate MIPI C-PHY and
D-PHY from each other. So I think we'll need that property for CSI-2
nevertheless. How about:

0 - autodetect based on other properties (MIPI CSI-2 D-PHY, parallel or Bt656)
1 - MIPI CSI-2 C-PHY
2 - MIPI CSI1
3 - CCP2 

I wouldn't add a separate entry for the parallel case as there are plenty of
existing DT binaries with parallel interface configuration without phy-type
property. They will need to be continue to be supported anyway, so there's
not too much value in adding a type for that purpose.

I do find this a bit annoying; we should have had something like phy-type
from day one rather than try to guess which phy is being used...

> +  1 - MIPI CSI1
> +  2 - CCP2
> +  Autodetection is default, and bus-type property may be omitted in that case.
>  - bus-width: number of data lines actively used, valid for the parallel busses.
>  - data-shift: on the parallel data busses, if bus-width is used to specify the
>    number of data lines, data-shift can be used to specify which data lines are
> 
> 


-- 
Kind regards,

Sakari Ailus
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Re: [PATCHv2] dt: bindings: Add support for CSI1 bus

[Pavel Machek]

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From: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>

In the vast majority of cases the bus type is known to the driver(s)
since a receiver or transmitter can only support a single one. There
are cases however where different options are possible.

The existing V4L2 OF support tries to figure out the bus type and
parse the bus parameters based on that. This does not scale too well
as there are multiple serial busses that share common properties.

Some hardware also supports multiple types of busses on the same
interfaces.

Document the CSI1/CCP2 property strobe. It signifies the clock or
strobe mode.
 
Signed-off-by: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Signed-off-by: Pavel Machek <pavel-+ZI9xUNit7I@public.gmane.org>
Reviewed-By: Sebastian Reichel <sre-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>

diff --git a/Documentation/devicetree/bindings/media/video-interfaces.txt b/Documentation/devicetree/bindings/media/video-interfaces.txt
index 9cd2a36..6986fde 100644
--- a/Documentation/devicetree/bindings/media/video-interfaces.txt
+++ b/Documentation/devicetree/bindings/media/video-interfaces.txt
@@ -76,6 +76,12 @@ Optional endpoint properties
   mode horizontal and vertical synchronization signals are provided to the
   slave device (data source) by the master device (data sink). In the master
   mode the data source device is also the source of the synchronization signals.
+- bus-type: data bus type. Possible values are:
+  0 - autodetect based on other properties (MIPI CSI-2 D-PHY, parallel or Bt656)
+  1 - MIPI CSI-2 C-PHY
+  2 - MIPI CSI1
+  3 - CCP2
+  Autodetection is default, and bus-type property may be omitted in that case.
 - bus-width: number of data lines actively used, valid for the parallel busses.
 - data-shift: on the parallel data busses, if bus-width is used to specify the
   number of data lines, data-shift can be used to specify which data lines are
@@ -112,7 +118,8 @@ Optional endpoint properties
   should be the combined length of data-lanes and clock-lanes properties.
   If the lane-polarities property is omitted, the value must be interpreted
   as 0 (normal). This property is valid for serial busses only.
-
+- strobe: Whether the clock signal is used as clock or strobe. Used
+  with CCP2, for instance.
 
 Example
 -------

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Re: [PATCHv2] dt: bindings: Add support for CSI1 bus

[Pavel Machek]

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Hi!

> >  - bus-type: data bus type. Possible values are:
> > -  0 - MIPI CSI2
> > -  1 - parallel / Bt656
> > -  2 - MIPI CSI1
> > -  3 - CCP2
> > +  0 - autodetect based on other properties (MIPI CSI2, parallel, Bt656)
> 
> In the meantime, I also realised that we need to separate MIPI C-PHY and
> D-PHY from each other. So I think we'll need that property for CSI-2
> nevertheless. How about:
> 
> 0 - autodetect based on other properties (MIPI CSI-2 D-PHY, parallel or Bt656)
> 1 - MIPI CSI-2 C-PHY
> 2 - MIPI CSI1
> 3 - CCP2 
> 
> I wouldn't add a separate entry for the parallel case as there are plenty of
> existing DT binaries with parallel interface configuration without phy-type
> property. They will need to be continue to be supported anyway, so there's
> not too much value in adding a type for that purpose.
> 
> I do find this a bit annoying; we should have had something like phy-type
> from day one rather than try to guess which phy is being used...

Ok, v3 is in the mail. 

									Pavel
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(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [PATCHv2] dt: bindings: Add support for CSI1 bus

[Sakari Ailus]

Hi Pavel,

On Mon, Feb 06, 2017 at 10:49:57AM +0100, Pavel Machek wrote:
> From: Sakari Ailus <sakari.ailus@iki.fi>
> 
> In the vast majority of cases the bus type is known to the driver(s)
> since a receiver or transmitter can only support a single one. There
> are cases however where different options are possible.
> 
> The existing V4L2 OF support tries to figure out the bus type and
> parse the bus parameters based on that. This does not scale too well
> as there are multiple serial busses that share common properties.
> 
> Some hardware also supports multiple types of busses on the same
> interfaces.
> 
> Document the CSI1/CCP2 property strobe. It signifies the clock or
> strobe mode.

Thanks. I split this into two (bus type + strobe). The result is in here:

<URL:https://git.linuxtv.org/sailus/media_tree.git/commit/?h=ccp2>

How about the rest? :-) I guess we could get the CCP2 support in omap3isp
without the video bus switch. It'd be nice to have this in a single
patchset.

-- 
Kind regards,

Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

Re: [PATCHv2] dt: bindings: Add support for CSI1 bus

[Rob Herring]

On Mon, Feb 06, 2017 at 10:49:57AM +0100, Pavel Machek wrote:
> From: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> 
> In the vast majority of cases the bus type is known to the driver(s)
> since a receiver or transmitter can only support a single one. There
> are cases however where different options are possible.
> 
> The existing V4L2 OF support tries to figure out the bus type and
> parse the bus parameters based on that. This does not scale too well
> as there are multiple serial busses that share common properties.
> 
> Some hardware also supports multiple types of busses on the same
> interfaces.
> 
> Document the CSI1/CCP2 property strobe. It signifies the clock or
> strobe mode.
>  
> Signed-off-by: Sakari Ailus <sakari.ailus-X3B1VOXEql0@public.gmane.org>
> Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Signed-off-by: Pavel Machek <pavel-+ZI9xUNit7I@public.gmane.org>
> Reviewed-By: Sebastian Reichel <sre-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>

Acked-by: Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
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