Re: [PATCH v4 1/1] iio:pressure: initial zpa2326 barometer support

[jic23-tko9wxEg+fIOOJlXag/Snyp2UmYkHbXO@public.gmane.org]

On 13.09.2016 08:55, Gregor Boirie wrote:
> Hi,
> 
> On 09/10/2016 05:37 PM, Jonathan Cameron wrote:
>> On 09/09/16 16:01, Gregor Boirie wrote:
>>> Introduce driver for Murata ZPA2326 pressure and temperature sensor:
>>> http://www.murata.com/en-us/products/productdetail?partno=ZPA2326-0311A-R
>>> 
>>> Signed-off-by: Gregor Boirie <gregor.boirie-ITF29qwbsa/QT0dZR+AlfA@public.gmane.org>
>> This looks pretty good to me now.  A few minor bits and bobs inline.
>> 
>> I almost took it as is, but would like to have it sit on the list
>> in it's current form for a few more days anyway so might as well get
>> these few corners tidied up!
> [...]
>> 
>> +/*
>> + * Debugfs stuff
>> + *
>> + * We want to prevent debugfs hooks from altering configuration while 
>> chip
>> + * sampling is ongoing to preserve data consistency. Moreover, a few 
>> registers,
>> + * when read, change hardware state, e.g. interrupt acknowlege on 
>> read. This is
>> + * why debugfs read and write hooks acquire exclusive access to 
>> register space.
>> + *
>> + * Also note this is mostly unusable with power management enabled 
>> systems since
>> + * registers content is lost during power off -> on transitions.
>> + */
>> It would be nice perhaps to tighten up the range of addresses that
>> we are protecting.  Thus allow reading of any addresses that are not
>> 'fragile'.  Only supported limited debug access is hardly a big
>> issue however ;)
> Quite frankly, I wonder if this debugfs stuff should not be thrown
> away given that
> regmap already provides a way to access registers over debugfs (with
> very limited
> protection...).
> What do you think ?
> 
> [...]
Agreed. Bin it.
> 
> Regards,
> Grégor.
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