Re: [PATCH v7 06/10] iio: adc: Support ROHM BD79124 ADC

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Sun, Mar 30, 2025 at 05:04:36PM +0100, Jonathan Cameron wrote:
> On Mon, 17 Mar 2025 13:24:07 +0200
> Matti Vaittinen <mazziesaccount@gmail.com> wrote:
> > On 16/03/2025 13:02, Jonathan Cameron wrote:
> > > On Thu, 13 Mar 2025 09:19:03 +0200
> > > Matti Vaittinen <mazziesaccount@gmail.com> wrote:  

...

> > >> +	return (data->alarm_monitored[chan->channel] & BIT(dir));  
> > > 
> > > Drop the outer brackets as not adding anything.  
> > 
> > I just noticed that the integer returned from here is directly provided 
> > to the user-space. I don't know the history, but it feels a bit off to 
> > me. I mean, I would expect the read from sysfs file "*_en" to return '1' 
> > or '0' - not 0x04.
> > 
> > Oh well, I suppose it's too late to change this in the IIO core - but 
> > I'll do:
> > 	return !!(data->alarm_monitored[chan->channel] & BIT(dir));
> 
> Agreed it should be returning 1 or 0.
> 
> This stuff is a little bit messy.  I'd not be against that ABI
> cleanup if we squashed the values to 0,1 in the core as a follow up.
> 
> I doubt anyone relies on getting 0x4 as that would be very driver
> specific userspace code!

FWIW, the time this discussion was held, I looked at the code and it seems
we have such drivers. I doubt we can change it without potential breakage of
(some) user space tools.

-- 
With Best Regards,
Andy Shevchenko