diff mbox

[1/2] dt-bindings/display/bridge: sii902x: add optional power supplies

Message ID 20180410051927.8268-2-philippe.cornu@st.com (mailing list archive)
State New, archived
Headers show

Commit Message

Philippe CORNU April 10, 2018, 5:19 a.m. UTC
Add the 3 optional power supplies using the exact description
found in the document named
"SiI9022A/SiI9024A HDMI Transmitter Data Sheet (August 2016)".

Signed-off-by: Philippe Cornu <philippe.cornu@st.com>
---
 Documentation/devicetree/bindings/display/bridge/sii902x.txt | 3 +++
 1 file changed, 3 insertions(+)

Comments

Rob Herring April 13, 2018, 5:58 p.m. UTC | #1
On Tue, Apr 10, 2018 at 07:19:26AM +0200, Philippe Cornu wrote:
> Add the 3 optional power supplies using the exact description
> found in the document named
> "SiI9022A/SiI9024A HDMI Transmitter Data Sheet (August 2016)".
> 
> Signed-off-by: Philippe Cornu <philippe.cornu@st.com>
> ---
>  Documentation/devicetree/bindings/display/bridge/sii902x.txt | 3 +++
>  1 file changed, 3 insertions(+)

Reviewed-by: Rob Herring <robh@kernel.org>
Laurent Pinchart April 19, 2018, 8:11 a.m. UTC | #2
Hi Philippe,

Thank you for the patch.

On Tuesday, 10 April 2018 08:19:26 EEST Philippe Cornu wrote:
> Add the 3 optional power supplies using the exact description
> found in the document named
> "SiI9022A/SiI9024A HDMI Transmitter Data Sheet (August 2016)".
> 
> Signed-off-by: Philippe Cornu <philippe.cornu@st.com>
> ---
>  Documentation/devicetree/bindings/display/bridge/sii902x.txt | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/display/bridge/sii902x.txt
> b/Documentation/devicetree/bindings/display/bridge/sii902x.txt index
> 56a3e68ccb80..cf53678fe574 100644
> --- a/Documentation/devicetree/bindings/display/bridge/sii902x.txt
> +++ b/Documentation/devicetree/bindings/display/bridge/sii902x.txt
> @@ -8,6 +8,9 @@ Optional properties:
>  	- interrupts-extended or interrupt-parent + interrupts: describe
>  	  the interrupt line used to inform the host about hotplug events.
>  	- reset-gpios: OF device-tree gpio specification for RST_N pin.
> +	- iovcc-supply: I/O supply voltage (1.8V or 3.3V, host-dependent).
> +	- avcc12-supply: TMDS analog supply voltage (1.2V).
> +	- cvcc12-supply: Digital core supply voltage (1.2V).

It seems that the AVCC12 and CVCC12 power supplies are usually derived from 
the same source. How about starting with one DT property for both, and adding 
a second one later if needed ?

>  Optional subnodes:
>  	- video input: this subnode can contain a video input port node
Philippe CORNU April 19, 2018, 9:31 a.m. UTC | #3
Hi Laurent : )

On 04/19/2018 10:11 AM, Laurent Pinchart wrote:
> Hi Philippe,

> 

> Thank you for the patch.

> 

> On Tuesday, 10 April 2018 08:19:26 EEST Philippe Cornu wrote:

>> Add the 3 optional power supplies using the exact description

>> found in the document named

>> "SiI9022A/SiI9024A HDMI Transmitter Data Sheet (August 2016)".

>>

>> Signed-off-by: Philippe Cornu <philippe.cornu@st.com>

>> ---

>>   Documentation/devicetree/bindings/display/bridge/sii902x.txt | 3 +++

>>   1 file changed, 3 insertions(+)

>>

>> diff --git a/Documentation/devicetree/bindings/display/bridge/sii902x.txt

>> b/Documentation/devicetree/bindings/display/bridge/sii902x.txt index

>> 56a3e68ccb80..cf53678fe574 100644

>> --- a/Documentation/devicetree/bindings/display/bridge/sii902x.txt

>> +++ b/Documentation/devicetree/bindings/display/bridge/sii902x.txt

>> @@ -8,6 +8,9 @@ Optional properties:

>>   	- interrupts-extended or interrupt-parent + interrupts: describe

>>   	  the interrupt line used to inform the host about hotplug events.

>>   	- reset-gpios: OF device-tree gpio specification for RST_N pin.

>> +	- iovcc-supply: I/O supply voltage (1.8V or 3.3V, host-dependent).

>> +	- avcc12-supply: TMDS analog supply voltage (1.2V).

>> +	- cvcc12-supply: Digital core supply voltage (1.2V).

> 

> It seems that the AVCC12 and CVCC12 power supplies are usually derived from

> the same source. How about starting with one DT property for both, and adding

> a second one later if needed ?

> 


Well, I do not know what is the best. Here I took the description from 
the documentation, and to allow all possible board configurations, I 
added these supplies as "optional" properties: if there is only one 1v2 
regulator on the board, the dt will contain only avcc12 or cvcc12 and 
everything will work fine (we will have a dummy regulator for the 
missing optional 1v2 reg), if both regulators are there for any reasons 
(stability, noise, whatever...) then both entries will be in the dt.

If you confirm you prefer a single 1v2 supply (named for instance 
"vcc12-supply") then I will do :-)

Many thanks,
Philippe


>>   Optional subnodes:

>>   	- video input: this subnode can contain a video input port node

>
Laurent Pinchart April 19, 2018, 11:09 a.m. UTC | #4
Hi Philippe,

On Thursday, 19 April 2018 12:31:15 EEST Philippe CORNU wrote:
> On 04/19/2018 10:11 AM, Laurent Pinchart wrote:
> > On Tuesday, 10 April 2018 08:19:26 EEST Philippe Cornu wrote:
> > 
> >> Add the 3 optional power supplies using the exact description
> >> found in the document named
> >> "SiI9022A/SiI9024A HDMI Transmitter Data Sheet (August 2016)".
> >>
> >> Signed-off-by: Philippe Cornu <philippe.cornu@st.com>
> >> ---
> >> 
> >>   Documentation/devicetree/bindings/display/bridge/sii902x.txt | 3 +++
> >>   1 file changed, 3 insertions(+)
> >>
> >> diff --git
> >> a/Documentation/devicetree/bindings/display/bridge/sii902x.txt
> >> b/Documentation/devicetree/bindings/display/bridge/sii902x.txt index
> >> 56a3e68ccb80..cf53678fe574 100644
> >> --- a/Documentation/devicetree/bindings/display/bridge/sii902x.txt
> >> +++ b/Documentation/devicetree/bindings/display/bridge/sii902x.txt
> >> @@ -8,6 +8,9 @@ Optional properties:
> >>   	- interrupts-extended or interrupt-parent + interrupts: describe
> >>   	  the interrupt line used to inform the host about hotplug events.
> >>   	- reset-gpios: OF device-tree gpio specification for RST_N pin.
> >> +	- iovcc-supply: I/O supply voltage (1.8V or 3.3V, host-dependent).
> >> +	- avcc12-supply: TMDS analog supply voltage (1.2V).
> >> +	- cvcc12-supply: Digital core supply voltage (1.2V).
> > 
> > It seems that the AVCC12 and CVCC12 power supplies are usually derived
> > from the same source. How about starting with one DT property for both,
> > and adding a second one later if needed ?
> 
> Well, I do not know what is the best. Here I took the description from 
> the documentation, and to allow all possible board configurations, I 
> added these supplies as "optional" properties: if there is only one 1v2 
> regulator on the board, the dt will contain only avcc12 or cvcc12 and 
> everything will work fine (we will have a dummy regulator for the 
> missing optional 1v2 reg), if both regulators are there for any reasons 
> (stability, noise, whatever...) then both entries will be in the dt.
> 
> If you confirm you prefer a single 1v2 supply (named for instance 
> "vcc12-supply") then I will do :-)

Please see https://lists.freedesktop.org/archives/dri-devel/2018-April/
172400.html (and the messages that lead to it) and https://
lists.freedesktop.org/archives/dri-devel/2018-March/170763.html.

> >>   Optional subnodes:
> >>   	- video input: this subnode can contain a video input port node
Philippe CORNU April 19, 2018, 12:41 p.m. UTC | #5
Hi Laurent,


On 04/19/2018 01:09 PM, Laurent Pinchart wrote:
> Hi Philippe,

> 

> On Thursday, 19 April 2018 12:31:15 EEST Philippe CORNU wrote:

>> On 04/19/2018 10:11 AM, Laurent Pinchart wrote:

>>> On Tuesday, 10 April 2018 08:19:26 EEST Philippe Cornu wrote:

>>>

>>>> Add the 3 optional power supplies using the exact description

>>>> found in the document named

>>>> "SiI9022A/SiI9024A HDMI Transmitter Data Sheet (August 2016)".

>>>>

>>>> Signed-off-by: Philippe Cornu <philippe.cornu@st.com>

>>>> ---

>>>>

>>>>    Documentation/devicetree/bindings/display/bridge/sii902x.txt | 3 +++

>>>>    1 file changed, 3 insertions(+)

>>>>

>>>> diff --git

>>>> a/Documentation/devicetree/bindings/display/bridge/sii902x.txt

>>>> b/Documentation/devicetree/bindings/display/bridge/sii902x.txt index

>>>> 56a3e68ccb80..cf53678fe574 100644

>>>> --- a/Documentation/devicetree/bindings/display/bridge/sii902x.txt

>>>> +++ b/Documentation/devicetree/bindings/display/bridge/sii902x.txt

>>>> @@ -8,6 +8,9 @@ Optional properties:

>>>>    	- interrupts-extended or interrupt-parent + interrupts: describe

>>>>    	  the interrupt line used to inform the host about hotplug events.

>>>>    	- reset-gpios: OF device-tree gpio specification for RST_N pin.

>>>> +	- iovcc-supply: I/O supply voltage (1.8V or 3.3V, host-dependent).

>>>> +	- avcc12-supply: TMDS analog supply voltage (1.2V).

>>>> +	- cvcc12-supply: Digital core supply voltage (1.2V).

>>>

>>> It seems that the AVCC12 and CVCC12 power supplies are usually derived

>>> from the same source. How about starting with one DT property for both,

>>> and adding a second one later if needed ?

>>

>> Well, I do not know what is the best. Here I took the description from

>> the documentation, and to allow all possible board configurations, I

>> added these supplies as "optional" properties: if there is only one 1v2

>> regulator on the board, the dt will contain only avcc12 or cvcc12 and

>> everything will work fine (we will have a dummy regulator for the

>> missing optional 1v2 reg), if both regulators are there for any reasons

>> (stability, noise, whatever...) then both entries will be in the dt.

>>

>> If you confirm you prefer a single 1v2 supply (named for instance

>> "vcc12-supply") then I will do :-)

> 

> Please see https://lists.freedesktop.org/archives/dri-devel/2018-April/

> 172400.html (and the messages that lead to it) and https://

> lists.freedesktop.org/archives/dri-devel/2018-March/170763.html.

> 


Thanks for this discussion thread.

On my side, I found "CVCC12 and AVCC12 can be derived from the same 
power source" written with a small font (august 2016 datasheet p13) so 
then your advice is clearly what we have to do :-)
I will add this info in v2 too.
Thank you,
Philippe :-)

>>>>    Optional subnodes:

>>>>    	- video input: this subnode can contain a video input port node

>
Laurent Pinchart April 19, 2018, 12:50 p.m. UTC | #6
Hi Philippe,

On Thursday, 19 April 2018 15:41:20 EEST Philippe CORNU wrote:
> On 04/19/2018 01:09 PM, Laurent Pinchart wrote:
> > On Thursday, 19 April 2018 12:31:15 EEST Philippe CORNU wrote:
> >> On 04/19/2018 10:11 AM, Laurent Pinchart wrote:
> >>> On Tuesday, 10 April 2018 08:19:26 EEST Philippe Cornu wrote:
> >>>> Add the 3 optional power supplies using the exact description
> >>>> found in the document named
> >>>> "SiI9022A/SiI9024A HDMI Transmitter Data Sheet (August 2016)".
> >>>>
> >>>> Signed-off-by: Philippe Cornu <philippe.cornu@st.com>
> >>>> ---
> >>>>
> >>>> Documentation/devicetree/bindings/display/bridge/sii902x.txt | 3 +++
> >>>> 1 file changed, 3 insertions(+)
> >>>>
> >>>> diff --git
> >>>> a/Documentation/devicetree/bindings/display/bridge/sii902x.txt
> >>>> b/Documentation/devicetree/bindings/display/bridge/sii902x.txt index
> >>>> 56a3e68ccb80..cf53678fe574 100644
> >>>> --- a/Documentation/devicetree/bindings/display/bridge/sii902x.txt
> >>>> +++ b/Documentation/devicetree/bindings/display/bridge/sii902x.txt
> >>>> @@ -8,6 +8,9 @@ Optional properties:
> >>>>    	- interrupts-extended or interrupt-parent + interrupts: describe
> >>>>    	  the interrupt line used to inform the host about hotplug events.
> >>>>    	- reset-gpios: OF device-tree gpio specification for RST_N pin.
> >>>> +	- iovcc-supply: I/O supply voltage (1.8V or 3.3V, host-dependent).
> >>>> +	- avcc12-supply: TMDS analog supply voltage (1.2V).
> >>>> +	- cvcc12-supply: Digital core supply voltage (1.2V).
> >>>
> >>> It seems that the AVCC12 and CVCC12 power supplies are usually derived
> >>> from the same source. How about starting with one DT property for both,
> >>> and adding a second one later if needed ?
> >>
> >> Well, I do not know what is the best. Here I took the description from
> >> the documentation, and to allow all possible board configurations, I
> >> added these supplies as "optional" properties: if there is only one 1v2
> >> regulator on the board, the dt will contain only avcc12 or cvcc12 and
> >> everything will work fine (we will have a dummy regulator for the
> >> missing optional 1v2 reg), if both regulators are there for any reasons
> >> (stability, noise, whatever...) then both entries will be in the dt.
> >>
> >> If you confirm you prefer a single 1v2 supply (named for instance
> >> "vcc12-supply") then I will do :-)
> > 
> > Please see https://lists.freedesktop.org/archives/dri-devel/2018-April/
> > 172400.html (and the messages that lead to it) and https://
> > lists.freedesktop.org/archives/dri-devel/2018-March/170763.html.
> 
> Thanks for this discussion thread.
> 
> On my side, I found "CVCC12 and AVCC12 can be derived from the same 
> power source" written with a small font (august 2016 datasheet p13) so 
> then your advice is clearly what we have to do :-)
> I will add this info in v2 too.

I have seen that too. While the datasheet only says that the two supplies 
*can* be derived from the same power source, I expect that to be the case in 
practice for a really vast majority of cases (I wouldn't be surprised to never 
hear of a system using two different supplies). That's why I think starting 
with one supply would be better.

> >>>>    Optional subnodes:
> >>>>    
> >>>>    	- video input: this subnode can contain a video input port node
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/display/bridge/sii902x.txt b/Documentation/devicetree/bindings/display/bridge/sii902x.txt
index 56a3e68ccb80..cf53678fe574 100644
--- a/Documentation/devicetree/bindings/display/bridge/sii902x.txt
+++ b/Documentation/devicetree/bindings/display/bridge/sii902x.txt
@@ -8,6 +8,9 @@  Optional properties:
 	- interrupts-extended or interrupt-parent + interrupts: describe
 	  the interrupt line used to inform the host about hotplug events.
 	- reset-gpios: OF device-tree gpio specification for RST_N pin.
+	- iovcc-supply: I/O supply voltage (1.8V or 3.3V, host-dependent).
+	- avcc12-supply: TMDS analog supply voltage (1.2V).
+	- cvcc12-supply: Digital core supply voltage (1.2V).
 
 Optional subnodes:
 	- video input: this subnode can contain a video input port node