[PATCH v2] Docs: iio: ad7191 Correct clock configuration

[PATCH v2] Docs: iio: ad7191 Correct clock configuration

[Ammar Mustafa]

Correct the ad7191 documentation to match the datasheet:
- Fix inverted CLKSEL pin logic: device uses external clock when pin is
  inactive, and internal CMOS/crystal when high.
- Correct CMOS-compatible clock pin from MCLK2 to MCLK1.

Signed-off-by: Ammar Mustafa <ammarmustafa34@gmail.com>
---
Changes since v1:
- Instead of using "tied high" or "tied low", change to active or inactive
to remove confusion.
- Undo the swap of entries from previous patch.

 Documentation/iio/ad7191.rst | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/Documentation/iio/ad7191.rst b/Documentation/iio/ad7191.rst
index 977d4fea14b0..fd6a23ad44fd 100644
--- a/Documentation/iio/ad7191.rst
+++ b/Documentation/iio/ad7191.rst
@@ -63,11 +63,11 @@ Clock Configuration
 
 The AD7191 supports both internal and external clock sources:
 
-- When CLKSEL pin is tied LOW: Uses internal 4.92MHz clock (no clock property
+- When CLKSEL pin is ACTIVE: Uses internal 4.92MHz clock (no clock property
   needed)
-- When CLKSEL pin is tied HIGH: Requires external clock source
+- When CLKSEL pin is INACTIVE: Requires external clock source
   - Can be a crystal between MCLK1 and MCLK2 pins
-  - Or a CMOS-compatible clock driving MCLK2 pin
+  - Or a CMOS-compatible clock driving MCLK1 pin and MCLK2 left unconnected
   - Must specify the "clocks" property in device tree when using external clock
 
 SPI Interface Requirements
-- 
2.43.0

Re: [PATCH v2] Docs: iio: ad7191 Correct clock configuration

[Andy Shevchenko]

On Fri, Feb 27, 2026 at 02:08:33PM -0500, Ammar Mustafa wrote:
> Correct the ad7191 documentation to match the datasheet:
> - Fix inverted CLKSEL pin logic: device uses external clock when pin is
>   inactive, and internal CMOS/crystal when high.

high --> active

Thanks, this part looks good in the below documentation update.

> - Correct CMOS-compatible clock pin from MCLK2 to MCLK1.

I haven't checked driver yet, but is it only for a single component?
Can you double check that _all_ supported by the driver have the same
in their datasheet(s)?

...

> +- When CLKSEL pin is ACTIVE: Uses internal 4.92MHz clock (no clock property
>    needed)
> -- When CLKSEL pin is tied HIGH: Requires external clock source
> +- When CLKSEL pin is INACTIVE: Requires external clock source
>    - Can be a crystal between MCLK1 and MCLK2 pins
> -  - Or a CMOS-compatible clock driving MCLK2 pin
> +  - Or a CMOS-compatible clock driving MCLK1 pin and MCLK2 left unconnected
>    - Must specify the "clocks" property in device tree when using external clock

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v2] Docs: iio: ad7191 Correct clock configuration

[Jonathan Cameron]

On Sat, 28 Feb 2026 12:50:46 +0200
Andy Shevchenko <andriy.shevchenko@intel.com> wrote:

> On Fri, Feb 27, 2026 at 02:08:33PM -0500, Ammar Mustafa wrote:
> > Correct the ad7191 documentation to match the datasheet:
> > - Fix inverted CLKSEL pin logic: device uses external clock when pin is
> >   inactive, and internal CMOS/crystal when high.  
> 
> high --> active
> 
> Thanks, this part looks good in the below documentation update.
> 
> > - Correct CMOS-compatible clock pin from MCLK2 to MCLK1.  
> 
> I haven't checked driver yet, but is it only for a single component?
> Can you double check that _all_ supported by the driver have the same
> in their datasheet(s)?
> 
> ...

Hi Ammar,

Just a quick note to say I'm going to mark this one in patchwork
as needing a new version given Andy's questions have been here a while.

Thanks,

Jonathan

> 
> > +- When CLKSEL pin is ACTIVE: Uses internal 4.92MHz clock (no clock property
> >    needed)
> > -- When CLKSEL pin is tied HIGH: Requires external clock source
> > +- When CLKSEL pin is INACTIVE: Requires external clock source
> >    - Can be a crystal between MCLK1 and MCLK2 pins
> > -  - Or a CMOS-compatible clock driving MCLK2 pin
> > +  - Or a CMOS-compatible clock driving MCLK1 pin and MCLK2 left unconnected
> >    - Must specify the "clocks" property in device tree when using external clock  
> 

Re: [PATCH v2] Docs: iio: ad7191 Correct clock configuration

[Ammar Mustafa]

On Sun, Mar 22, 2026 at 12:13:14PM +0000, Jonathan Cameron wrote:
> On Sat, 28 Feb 2026 12:50:46 +0200
> Andy Shevchenko <andriy.shevchenko@intel.com> wrote:
> 
> > On Fri, Feb 27, 2026 at 02:08:33PM -0500, Ammar Mustafa wrote:
> > > Correct the ad7191 documentation to match the datasheet:
> > > - Fix inverted CLKSEL pin logic: device uses external clock when pin is
> > >   inactive, and internal CMOS/crystal when high.  
> > 
> > high --> active
> > 
> > Thanks, this part looks good in the below documentation update.
> > 
> > > - Correct CMOS-compatible clock pin from MCLK2 to MCLK1.  
> > 
> > I haven't checked driver yet, but is it only for a single component?
> > Can you double check that _all_ supported by the driver have the same
> > in their datasheet(s)?
> > 
> > ...
> 
> Hi Ammar,
> 
> Just a quick note to say I'm going to mark this one in patchwork
> as needing a new version given Andy's questions have been here a while.
> 
> Thanks,
> 
> Jonathan
> 
> > 
> > > +- When CLKSEL pin is ACTIVE: Uses internal 4.92MHz clock (no clock property
> > >    needed)
> > > -- When CLKSEL pin is tied HIGH: Requires external clock source
> > > +- When CLKSEL pin is INACTIVE: Requires external clock source
> > >    - Can be a crystal between MCLK1 and MCLK2 pins
> > > -  - Or a CMOS-compatible clock driving MCLK2 pin
> > > +  - Or a CMOS-compatible clock driving MCLK1 pin and MCLK2 left unconnected
> > >    - Must specify the "clocks" property in device tree when using external clock  
> > 
> 

Hi Jonathon, 

I replied to Andy's questionm not sure if I can attach it in mutt for you,
but we found that this driver only supports the AD7191 so no other 
documentation needs to be updated or check for this issue. 
Let me know if I need to do anything else to have this patch merged.

Thank you,

Ammar Mustafa

Re: [PATCH v2] Docs: iio: ad7191 Correct clock configuration

[Jonathan Cameron]

On Thu, 26 Mar 2026 18:04:53 -0400
Ammar Mustafa <ammarmustafa34@gmail.com> wrote:

> On Sun, Mar 22, 2026 at 12:13:14PM +0000, Jonathan Cameron wrote:
> > On Sat, 28 Feb 2026 12:50:46 +0200
> > Andy Shevchenko <andriy.shevchenko@intel.com> wrote:
> >   
> > > On Fri, Feb 27, 2026 at 02:08:33PM -0500, Ammar Mustafa wrote:  
> > > > Correct the ad7191 documentation to match the datasheet:
> > > > - Fix inverted CLKSEL pin logic: device uses external clock when pin is
> > > >   inactive, and internal CMOS/crystal when high.    
> > > 
> > > high --> active
> > > 
> > > Thanks, this part looks good in the below documentation update.
> > >   
> > > > - Correct CMOS-compatible clock pin from MCLK2 to MCLK1.    
> > > 
> > > I haven't checked driver yet, but is it only for a single component?
> > > Can you double check that _all_ supported by the driver have the same
> > > in their datasheet(s)?
> > > 
> > > ...  
> > 
> > Hi Ammar,
> > 
> > Just a quick note to say I'm going to mark this one in patchwork
> > as needing a new version given Andy's questions have been here a while.
> > 
> > Thanks,
> > 
> > Jonathan
> >   
> > >   
> > > > +- When CLKSEL pin is ACTIVE: Uses internal 4.92MHz clock (no clock property
> > > >    needed)
> > > > -- When CLKSEL pin is tied HIGH: Requires external clock source
> > > > +- When CLKSEL pin is INACTIVE: Requires external clock source
> > > >    - Can be a crystal between MCLK1 and MCLK2 pins
> > > > -  - Or a CMOS-compatible clock driving MCLK2 pin
> > > > +  - Or a CMOS-compatible clock driving MCLK1 pin and MCLK2 left unconnected
> > > >    - Must specify the "clocks" property in device tree when using external clock    
> > >   
> >   
> 
> Hi Jonathon, 
> 
> I replied to Andy's questionm not sure if I can attach it in mutt for you,
> but we found that this driver only supports the AD7191 so no other 
> documentation needs to be updated or check for this issue. 
> Let me know if I need to do anything else to have this patch merged.
> 
Given it's docs, I'll a sneak it in (not so worried if this one gets
build time in linux-next).  Applied.

Thanks,

Jonathan

> Thank you,
> 
> Ammar Mustafa