[PATCH v13 0/1] V4L2: Documentation: hw_seek spacing, tuner/modulator

[PATCH v13 0/1] V4L2: Documentation: hw_seek spacing, tuner/modulator

[Matti J. Aaltonen]

Hello.

Thank you for the comments. Here are my comments to Hans's comments:

On Thu, 2010-10-14 at 08:41 +0200, ext Hans Verkuil wrote:
> 
> This can be improved a bit:

Yes...

> I think that for now we should only mention BLOCK_IO here since we do
> not know yet what controls would be used if the receiver would
> understand that. There are no devices yet that support that
> mode. Perhaps we should mention instead that if someone has hardware
> that can decode rds automagically that they should contact the
> mailing list.
> Can you also add a link to the "Reading RDS data"
> section when describing the BLOCK_IO capability?

I more or less did the above. 

> The RDS interface section should be extended with a "Writing RDS data"
> section, and a link should be added to that new section when
> describing the BLOCK_IO capability here.
> 
> Just read carefully through the "RDS interface" section and make sure
> it is no longer exclusively referring to the receiver API.
> 
> You should alse add a link to the "FM Transmitter Control Reference"
> section when describing the CONTROLS capability.


I added "Writing RDS data" section etc...

B.R.
Matti

Matti J. Aaltonen (1):
  Documentation: v4l: Add hw_seek spacing and two TUNER_RDS_CAP flags.

 Documentation/DocBook/v4l/dev-rds.xml              |   60 ++++++++++++++------
 .../DocBook/v4l/vidioc-s-hw-freq-seek.xml          |   10 +++-
 2 files changed, 51 insertions(+), 19 deletions(-)

[PATCH v13 1/1] Documentation: v4l: Add hw_seek spacing and two TUNER_RDS_CAP flags.

[Matti J. Aaltonen]

Add a couple of words about the spacing field in the HW seek struct,
also a few words about the new RDS tuner capability flags
V4L2_TUNER_CAP_RDS_BLOCK-IO and V4L2_TUNER_CAP_RDS_CONTROLS.

Signed-off-by: Matti J. Aaltonen <matti.j.aaltonen@nokia.com>
---
 Documentation/DocBook/v4l/dev-rds.xml              |   60 ++++++++++++++------
 .../DocBook/v4l/vidioc-s-hw-freq-seek.xml          |   10 +++-
 2 files changed, 51 insertions(+), 19 deletions(-)

diff --git a/Documentation/DocBook/v4l/dev-rds.xml b/Documentation/DocBook/v4l/dev-rds.xml
index 0869d70..5498753 100644
--- a/Documentation/DocBook/v4l/dev-rds.xml
+++ b/Documentation/DocBook/v4l/dev-rds.xml
@@ -3,15 +3,16 @@
       <para>The Radio Data System transmits supplementary
 information in binary format, for example the station name or travel
 information, on an inaudible audio subcarrier of a radio program. This
-interface is aimed at devices capable of receiving and decoding RDS
+interface is aimed at devices capable of receiving and/or transmitting RDS
 information.</para>
 
       <para>For more information see the core RDS standard <xref linkend="en50067" />
 and the RBDS standard <xref linkend="nrsc4" />.</para>
 
       <para>Note that the RBDS standard as is used in the USA is almost identical
-to the RDS standard. Any RDS decoder can also handle RBDS. Only some of the fields
-have slightly different meanings. See the RBDS standard for more information.</para>
+to the RDS standard. Any RDS decoder/encoder can also handle RBDS. Only some of the
+fields have slightly different meanings. See the RBDS standard for more
+information.</para>
 
       <para>The RBDS standard also specifies support for MMBS (Modified Mobile Search).
 This is a proprietary format which seems to be discontinued. The RDS interface does not
@@ -21,16 +22,26 @@ be needed, then please contact the linux-media mailing list: &v4l-ml;.</para>
   <section>
     <title>Querying Capabilities</title>
 
-    <para>Devices supporting the RDS capturing API
-set the <constant>V4L2_CAP_RDS_CAPTURE</constant> flag in
+    <para>Devices supporting the RDS capturing API set
+the <constant>V4L2_CAP_RDS_CAPTURE</constant> flag in
 the <structfield>capabilities</structfield> field of &v4l2-capability;
-returned by the &VIDIOC-QUERYCAP; ioctl.
-Any tuner that supports RDS will set the
-<constant>V4L2_TUNER_CAP_RDS</constant> flag in the <structfield>capability</structfield>
-field of &v4l2-tuner;.
-Whether an RDS signal is present can be detected by looking at
-the <structfield>rxsubchans</structfield> field of &v4l2-tuner;: the
-<constant>V4L2_TUNER_SUB_RDS</constant> will be set if RDS data was detected.</para>
+returned by the &VIDIOC-QUERYCAP; ioctl.  Any tuner that supports RDS
+will set the <constant>V4L2_TUNER_CAP_RDS</constant> flag in
+the <structfield>capability</structfield> field of &v4l2-tuner;.  If
+the driver only passes RDS blocks without interpreting the data
+the <constant>V4L2_TUNER_SUB_RDS_BLOCK_IO</constant> flag has to be
+set, see <link linkend="reading-rds-data">Reading RDS data</link>.
+For future use the
+flag <constant>V4L2_TUNER_SUB_RDS_CONTROLS</constant> has also been
+defined. However, a driver for a radio tuner with this capability does
+not yet exist, so if you are planning to write such a driver the best
+way to start would probably be by opening a discussion about it on
+the linux-media mailing list: &v4l-ml;. </para>
+
+    <para> Whether an RDS signal is present can be detected by looking
+at the <structfield>rxsubchans</structfield> field of &v4l2-tuner;:
+the <constant>V4L2_TUNER_SUB_RDS</constant> will be set if RDS data
+was detected.</para>
 
     <para>Devices supporting the RDS output API
 set the <constant>V4L2_CAP_RDS_OUTPUT</constant> flag in
@@ -40,16 +51,31 @@ Any modulator that supports RDS will set the
 <constant>V4L2_TUNER_CAP_RDS</constant> flag in the <structfield>capability</structfield>
 field of &v4l2-modulator;.
 In order to enable the RDS transmission one must set the <constant>V4L2_TUNER_SUB_RDS</constant>
-bit in the <structfield>txsubchans</structfield> field of &v4l2-modulator;.</para>
-
+bit in the <structfield>txsubchans</structfield> field of &v4l2-modulator;.
+If the driver only passes RDS blocks without interpreting the data
+the <constant>V4L2_TUNER_SUB_RDS_BLOCK_IO</constant> flag has to be set. If the
+tuner is capable of handling RDS entities like program identification codes and radio
+text, the flag <constant>V4L2_TUNER_SUB_RDS_CONTROLS</constant> should be set,
+see <link linkend="writing-rds-data">Writing RDS data</link> and
+<link linkend="fm-tx-controls">FM Transmitter Control Reference</link>.</para>
   </section>
 
-  <section>
+  <section  id="reading-rds-data">
     <title>Reading RDS data</title>
 
       <para>RDS data can be read from the radio device
-with the &func-read; function. The data is packed in groups of three bytes,
+with the &func-read; function. The data is packed in groups of three bytes.</para>
+  </section>
+
+  <section  id="writing-rds-data">
+    <title>Writing RDS data</title>
+
+      <para>RDS data can be written to the radio device
+with the &func-write; function. The data is packed in groups of three bytes,
 as follows:</para>
+  </section>
+
+  <section>
     <table frame="none" pgwide="1" id="v4l2-rds-data">
       <title>struct
 <structname>v4l2_rds_data</structname></title>
@@ -152,7 +178,7 @@ as follows:</para>
 	  <row>
 	    <entry>V4L2_RDS_BLOCK_ERROR</entry>
 	    <entry>0x80</entry>
-	    <entry>An incorrectable error occurred.</entry>
+	    <entry>An uncorrectable error occurred.</entry>
 	  </row>
 	</tbody>
       </tgroup>
diff --git a/Documentation/DocBook/v4l/vidioc-s-hw-freq-seek.xml b/Documentation/DocBook/v4l/vidioc-s-hw-freq-seek.xml
index 14b3ec7..c30dcc4 100644
--- a/Documentation/DocBook/v4l/vidioc-s-hw-freq-seek.xml
+++ b/Documentation/DocBook/v4l/vidioc-s-hw-freq-seek.xml
@@ -51,7 +51,8 @@
 
     <para>Start a hardware frequency seek from the current frequency.
 To do this applications initialize the <structfield>tuner</structfield>,
-<structfield>type</structfield>, <structfield>seek_upward</structfield> and
+<structfield>type</structfield>, <structfield>seek_upward</structfield>,
+<structfield>spacing</structfield> and
 <structfield>wrap_around</structfield> fields, and zero out the
 <structfield>reserved</structfield> array of a &v4l2-hw-freq-seek; and
 call the <constant>VIDIOC_S_HW_FREQ_SEEK</constant> ioctl with a pointer
@@ -89,7 +90,12 @@ field and the &v4l2-tuner; <structfield>index</structfield> field.</entry>
 	  </row>
 	  <row>
 	    <entry>__u32</entry>
-	    <entry><structfield>reserved</structfield>[8]</entry>
+	    <entry><structfield>spacing</structfield></entry>
+	    <entry>If non-zero, defines the hardware seek resolution in Hz. The driver selects the nearest value that is supported by the device. If spacing is zero a reasonable default value is used.</entry>
+	  </row>
+	  <row>
+	    <entry>__u32</entry>
+	    <entry><structfield>reserved</structfield>[7]</entry>
 	    <entry>Reserved for future extensions. Drivers and
 	    applications must set the array to zero.</entry>
 	  </row>
-- 
1.6.1.3

Re: [PATCH v13 1/1] Documentation: v4l: Add hw_seek spacing and two TUNER_RDS_CAP flags.

[Hans Verkuil]

Just a few very small comments:

> Add a couple of words about the spacing field in the HW seek struct,
> also a few words about the new RDS tuner capability flags
> V4L2_TUNER_CAP_RDS_BLOCK-IO and V4L2_TUNER_CAP_RDS_CONTROLS.
>
> Signed-off-by: Matti J. Aaltonen <matti.j.aaltonen@nokia.com>
> ---
>  Documentation/DocBook/v4l/dev-rds.xml              |   60
> ++++++++++++++------
>  .../DocBook/v4l/vidioc-s-hw-freq-seek.xml          |   10 +++-
>  2 files changed, 51 insertions(+), 19 deletions(-)
>
> diff --git a/Documentation/DocBook/v4l/dev-rds.xml
> b/Documentation/DocBook/v4l/dev-rds.xml
> index 0869d70..5498753 100644
> --- a/Documentation/DocBook/v4l/dev-rds.xml
> +++ b/Documentation/DocBook/v4l/dev-rds.xml
> @@ -3,15 +3,16 @@
>        <para>The Radio Data System transmits supplementary
>  information in binary format, for example the station name or travel
>  information, on an inaudible audio subcarrier of a radio program. This
> -interface is aimed at devices capable of receiving and decoding RDS
> +interface is aimed at devices capable of receiving and/or transmitting
> RDS
>  information.</para>
>
>        <para>For more information see the core RDS standard <xref
> linkend="en50067" />
>  and the RBDS standard <xref linkend="nrsc4" />.</para>
>
>        <para>Note that the RBDS standard as is used in the USA is almost
> identical
> -to the RDS standard. Any RDS decoder can also handle RBDS. Only some of
> the fields
> -have slightly different meanings. See the RBDS standard for more
> information.</para>
> +to the RDS standard. Any RDS decoder/encoder can also handle RBDS. Only
> some of the
> +fields have slightly different meanings. See the RBDS standard for more
> +information.</para>
>
>        <para>The RBDS standard also specifies support for MMBS (Modified
> Mobile Search).
>  This is a proprietary format which seems to be discontinued. The RDS
> interface does not
> @@ -21,16 +22,26 @@ be needed, then please contact the linux-media mailing
> list: &v4l-ml;.</para>
>    <section>
>      <title>Querying Capabilities</title>
>
> -    <para>Devices supporting the RDS capturing API
> -set the <constant>V4L2_CAP_RDS_CAPTURE</constant> flag in
> +    <para>Devices supporting the RDS capturing API set
> +the <constant>V4L2_CAP_RDS_CAPTURE</constant> flag in
>  the <structfield>capabilities</structfield> field of &v4l2-capability;
> -returned by the &VIDIOC-QUERYCAP; ioctl.
> -Any tuner that supports RDS will set the
> -<constant>V4L2_TUNER_CAP_RDS</constant> flag in the
> <structfield>capability</structfield>
> -field of &v4l2-tuner;.
> -Whether an RDS signal is present can be detected by looking at
> -the <structfield>rxsubchans</structfield> field of &v4l2-tuner;: the
> -<constant>V4L2_TUNER_SUB_RDS</constant> will be set if RDS data was
> detected.</para>
> +returned by the &VIDIOC-QUERYCAP; ioctl.  Any tuner that supports RDS
> +will set the <constant>V4L2_TUNER_CAP_RDS</constant> flag in
> +the <structfield>capability</structfield> field of &v4l2-tuner;.  If
> +the driver only passes RDS blocks without interpreting the data
> +the <constant>V4L2_TUNER_SUB_RDS_BLOCK_IO</constant> flag has to be
> +set, see <link linkend="reading-rds-data">Reading RDS data</link>.
> +For future use the
> +flag <constant>V4L2_TUNER_SUB_RDS_CONTROLS</constant> has also been
> +defined. However, a driver for a radio tuner with this capability does
> +not yet exist, so if you are planning to write such a driver the best
> +way to start would probably be by opening a discussion about it on
> +the linux-media mailing list: &v4l-ml;. </para>

Change to:

not yet exist, so if you are planning to write such a driver you
should discuss this on the linux-media mailing list: &v4l-ml;.</para>

> +
> +    <para> Whether an RDS signal is present can be detected by looking
> +at the <structfield>rxsubchans</structfield> field of &v4l2-tuner;:
> +the <constant>V4L2_TUNER_SUB_RDS</constant> will be set if RDS data
> +was detected.</para>
>
>      <para>Devices supporting the RDS output API
>  set the <constant>V4L2_CAP_RDS_OUTPUT</constant> flag in
> @@ -40,16 +51,31 @@ Any modulator that supports RDS will set the
>  <constant>V4L2_TUNER_CAP_RDS</constant> flag in the
> <structfield>capability</structfield>
>  field of &v4l2-modulator;.
>  In order to enable the RDS transmission one must set the
> <constant>V4L2_TUNER_SUB_RDS</constant>
> -bit in the <structfield>txsubchans</structfield> field of
> &v4l2-modulator;.</para>
> -
> +bit in the <structfield>txsubchans</structfield> field of
> &v4l2-modulator;.
> +If the driver only passes RDS blocks without interpreting the data
> +the <constant>V4L2_TUNER_SUB_RDS_BLOCK_IO</constant> flag has to be set.
> If the
> +tuner is capable of handling RDS entities like program identification
> codes and radio
> +text, the flag <constant>V4L2_TUNER_SUB_RDS_CONTROLS</constant> should be
> set,
> +see <link linkend="writing-rds-data">Writing RDS data</link> and
> +<link linkend="fm-tx-controls">FM Transmitter Control
> Reference</link>.</para>
>    </section>
>
> -  <section>
> +  <section  id="reading-rds-data">
>      <title>Reading RDS data</title>
>
>        <para>RDS data can be read from the radio device
> -with the &func-read; function. The data is packed in groups of three
> bytes,
> +with the &func-read; function. The data is packed in groups of three
> bytes.</para>
> +  </section>
> +
> +  <section  id="writing-rds-data">
> +    <title>Writing RDS data</title>
> +
> +      <para>RDS data can be written to the radio device
> +with the &func-write; function. The data is packed in groups of three
> bytes,
>  as follows:</para>
> +  </section>
> +
> +  <section>
>      <table frame="none" pgwide="1" id="v4l2-rds-data">
>        <title>struct
>  <structname>v4l2_rds_data</structname></title>
> @@ -152,7 +178,7 @@ as follows:</para>
>  	  <row>
>  	    <entry>V4L2_RDS_BLOCK_ERROR</entry>
>  	    <entry>0x80</entry>
> -	    <entry>An incorrectable error occurred.</entry>
> +	    <entry>An uncorrectable error occurred.</entry>

In addition to this change we should also specify that BLOCK_INVALID,
BLOCK_ERROR and BLOCK_CORRECTED are for reading only, not for writing.

>  	  </row>
>  	</tbody>
>        </tgroup>
> diff --git a/Documentation/DocBook/v4l/vidioc-s-hw-freq-seek.xml
> b/Documentation/DocBook/v4l/vidioc-s-hw-freq-seek.xml
> index 14b3ec7..c30dcc4 100644
> --- a/Documentation/DocBook/v4l/vidioc-s-hw-freq-seek.xml
> +++ b/Documentation/DocBook/v4l/vidioc-s-hw-freq-seek.xml
> @@ -51,7 +51,8 @@
>
>      <para>Start a hardware frequency seek from the current frequency.
>  To do this applications initialize the <structfield>tuner</structfield>,
> -<structfield>type</structfield>, <structfield>seek_upward</structfield>
> and
> +<structfield>type</structfield>, <structfield>seek_upward</structfield>,
> +<structfield>spacing</structfield> and
>  <structfield>wrap_around</structfield> fields, and zero out the
>  <structfield>reserved</structfield> array of a &v4l2-hw-freq-seek; and
>  call the <constant>VIDIOC_S_HW_FREQ_SEEK</constant> ioctl with a pointer
> @@ -89,7 +90,12 @@ field and the &v4l2-tuner;
> <structfield>index</structfield> field.</entry>
>  	  </row>
>  	  <row>
>  	    <entry>__u32</entry>
> -	    <entry><structfield>reserved</structfield>[8]</entry>
> +	    <entry><structfield>spacing</structfield></entry>
> +	    <entry>If non-zero, defines the hardware seek resolution in Hz. The
> driver selects the nearest value that is supported by the device. If
> spacing is zero a reasonable default value is used.</entry>
> +	  </row>
> +	  <row>
> +	    <entry>__u32</entry>
> +	    <entry><structfield>reserved</structfield>[7]</entry>
>  	    <entry>Reserved for future extensions. Drivers and
>  	    applications must set the array to zero.</entry>
>  	  </row>
> --
> 1.6.1.3
>
>

Regards,

        Hans

-- 
Hans Verkuil - video4linux developer - sponsored by TANDBERG, part of Cisco

Re: [PATCH v13 1/1] Documentation: v4l: Add hw_seek spacing and two TUNER_RDS_CAP flags.

[Mauro Carvalho Chehab]

Em 18-10-2010 11:17, Hans Verkuil escreveu:
> Just a few very small comments:

>> +For future use the
>> +flag <constant>V4L2_TUNER_SUB_RDS_CONTROLS</constant> has also been
>> +defined. However, a driver for a radio tuner with this capability does
>> +not yet exist, so if you are planning to write such a driver the best
>> +way to start would probably be by opening a discussion about it on
>> +the linux-media mailing list: &v4l-ml;. </para>
> 
> Change to:
> 
> not yet exist, so if you are planning to write such a driver you
> should discuss this on the linux-media mailing list: &v4l-ml;.</para>

No, please. Don't add any API capabilities at the DocBook without having a driver
using it. At the time a driver start needing it, we can just add the API bits
and doing the needed discussions as you've proposed. This is already implicit.

Cheers,
Mauro

Re: [PATCH v13 1/1] Documentation: v4l: Add hw_seek spacing and two TUNER_RDS_CAP flags.

[Hans Verkuil]

> Em 18-10-2010 11:17, Hans Verkuil escreveu:
>> Just a few very small comments:
>
>>> +For future use the
>>> +flag <constant>V4L2_TUNER_SUB_RDS_CONTROLS</constant> has also been
>>> +defined. However, a driver for a radio tuner with this capability does
>>> +not yet exist, so if you are planning to write such a driver the best
>>> +way to start would probably be by opening a discussion about it on
>>> +the linux-media mailing list: &v4l-ml;. </para>
>>
>> Change to:
>>
>> not yet exist, so if you are planning to write such a driver you
>> should discuss this on the linux-media mailing list: &v4l-ml;.</para>
>
> No, please. Don't add any API capabilities at the DocBook without having a
> driver
> using it. At the time a driver start needing it, we can just add the API
> bits
> and doing the needed discussions as you've proposed. This is already
> implicit.

These caps are shared between tuner and modulator. And for the modulator
both caps *are* used in Matti's driver. But while RDS_CONTROLS is
available for modulators, it is not yet applicable to tuners and for that
we need to make this note in the spec.

So this is an exception to the rule, I'm afraid.

Regards,

        Hans

-- 
Hans Verkuil - video4linux developer - sponsored by TANDBERG, part of Cisco

Re: [PATCH v13 1/1] Documentation: v4l: Add hw_seek spacing and two TUNER_RDS_CAP flags.

[Matti J. Aaltonen]

Hi.

On Mon, 2010-10-18 at 15:57 +0200, ext Hans Verkuil wrote:
> > Em 18-10-2010 11:17, Hans Verkuil escreveu:
> >> Just a few very small comments:
> >
> >>> +For future use the
> >>> +flag <constant>V4L2_TUNER_SUB_RDS_CONTROLS</constant> has also been
> >>> +defined. However, a driver for a radio tuner with this capability does
> >>> +not yet exist, so if you are planning to write such a driver the best
> >>> +way to start would probably be by opening a discussion about it on
> >>> +the linux-media mailing list: &v4l-ml;. </para>
> >>
> >> Change to:
> >>
> >> not yet exist, so if you are planning to write such a driver you
> >> should discuss this on the linux-media mailing list: &v4l-ml;.</para>
> >
> > No, please. Don't add any API capabilities at the DocBook without having a
> > driver
> > using it. At the time a driver start needing it, we can just add the API
> > bits
> > and doing the needed discussions as you've proposed. This is already
> > implicit.
> 
> These caps are shared between tuner and modulator. And for the modulator
> both caps *are* used in Matti's driver. But while RDS_CONTROLS is
> available for modulators, it is not yet applicable to tuners and for that
> we need to make this note in the spec.
> 
> So this is an exception to the rule, I'm afraid.

So it's ACK... or NACK?

Cheers,
Matti

> Regards,
> 
>         Hans
> 

Re: [PATCH v13 1/1] Documentation: v4l: Add hw_seek spacing and two TUNER_RDS_CAP flags.

[Hans Verkuil]

> Hi.
>
> On Mon, 2010-10-18 at 15:57 +0200, ext Hans Verkuil wrote:
>> > Em 18-10-2010 11:17, Hans Verkuil escreveu:
>> >> Just a few very small comments:
>> >
>> >>> +For future use the
>> >>> +flag <constant>V4L2_TUNER_SUB_RDS_CONTROLS</constant> has also been
>> >>> +defined. However, a driver for a radio tuner with this capability
>> does
>> >>> +not yet exist, so if you are planning to write such a driver the
>> best
>> >>> +way to start would probably be by opening a discussion about it on
>> >>> +the linux-media mailing list: &v4l-ml;. </para>
>> >>
>> >> Change to:
>> >>
>> >> not yet exist, so if you are planning to write such a driver you
>> >> should discuss this on the linux-media mailing list: &v4l-ml;.</para>
>> >
>> > No, please. Don't add any API capabilities at the DocBook without
>> having a
>> > driver
>> > using it. At the time a driver start needing it, we can just add the
>> API
>> > bits
>> > and doing the needed discussions as you've proposed. This is already
>> > implicit.
>>
>> These caps are shared between tuner and modulator. And for the modulator
>> both caps *are* used in Matti's driver. But while RDS_CONTROLS is
>> available for modulators, it is not yet applicable to tuners and for
>> that
>> we need to make this note in the spec.
>>
>> So this is an exception to the rule, I'm afraid.
>
> So it's ACK... or NACK?

ACK from me :-)

Regards,

       Hans

>
> Cheers,
> Matti
>
>> Regards,
>>
>>         Hans
>>
>
>
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-- 
Hans Verkuil - video4linux developer - sponsored by TANDBERG, part of Cisco

Re: [PATCH v13 1/1] Documentation: v4l: Add hw_seek spacing and two TUNER_RDS_CAP flags.

[Matti J. Aaltonen]

Hello.

On Mon, 2010-10-18 at 11:41 -0200, ext Mauro Carvalho Chehab wrote:
> Em 18-10-2010 11:17, Hans Verkuil escreveu:
> > Just a few very small comments:
> 
> >> +For future use the
> >> +flag <constant>V4L2_TUNER_SUB_RDS_CONTROLS</constant> has also been
> >> +defined. However, a driver for a radio tuner with this capability does
> >> +not yet exist, so if you are planning to write such a driver the best
> >> +way to start would probably be by opening a discussion about it on
> >> +the linux-media mailing list: &v4l-ml;. </para>
> > 
> > Change to:
> > 
> > not yet exist, so if you are planning to write such a driver you
> > should discuss this on the linux-media mailing list: &v4l-ml;.</para>
> 
> No, please. Don't add any API capabilities at the DocBook without having a driver
> using it. At the time a driver start needing it, we can just add the API bits
> and doing the needed discussions as you've proposed. This is already implicit.

I sent the fix suggested by Hans before I saw Mauro's comment. 

But the bit is already there and it's already being used by a modulator
driver... Is the consensus still that it should not be mentioned in
connection to tuners?

B.R.
Matti

> Cheers,
> Mauro