Re: [PATCH 2/3] iio: adc: ina3221: Add support for IIO ADC driver for TI INA3221

From: Laxman Dewangan <ldewangan@nvidia.com>
To: Guenter Roeck <linux@roeck-us.net>,
	Jonathan Cameron <jic23@kernel.org>, <robh+dt@kernel.org>,
	<corbet@lwn.net>, <lars@metafoo.de>
Cc: <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	<linux-doc@vger.kernel.org>, <linux-iio@vger.kernel.org>,
	<linux-hwmon@vger.kernel.org>, Jean Delvare <khali@linux-fr.org>,
	<afd@ti.com>
Subject: Re: [PATCH 2/3] iio: adc: ina3221: Add support for IIO ADC driver for TI INA3221
Date: Fri, 3 Jun 2016 19:44:01 +0530	[thread overview]
Message-ID: <575190A9.2090906@nvidia.com> (raw)
In-Reply-To: <5751863E.907@roeck-us.net>

On Friday 03 June 2016 06:59 PM, Guenter Roeck wrote:
> On 06/03/2016 03:06 AM, Jonathan Cameron wrote:
>> On 01/06/16 13:34, Laxman Dewangan wrote:
>>> The INA3221 is a three-channel, high-side current and bus voltage 
>>> monitor
>>> with an I2C interface from Texas Instruments. The INA3221 monitors both
>>> shunt voltage drops and bus supply voltages in addition to having
>>> programmable conversion times and averaging modes for these signals.
>>> The INA3221 offers both critical and warning alerts to detect multiple
>>> programmable out-of-range conditions for each channel.
>>>
>>> Add support for INA3221 SW driver via IIO ADC interface. The device is
>>> register as iio-device and provides interface for voltage/current 
>>> and power
>>> monitor. Also provide interface for setting oneshot/continuous mode and
>>> critical/warning threshold for the shunt voltage drop.
>>>
>>> Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
>> Hi Laxman,
>>
>> As ever with any driver lying on the border of IIO and hwmon, please 
>> include
>> a short justification of why you need an IIO driver and also cc the
>> hwmon list + maintainers. (cc'd on this reply).
>>
>> I simply won't take a driver where the hwmon maintainers aren't happy.
>> As it stands I'm not seeing obvious reasons in the code for why this
>> should be an IIO device.
>>
>
> Me not either.
>
> I have a hwmon driver for the same chip pending from Andrew Davis (TI)
> which I am just about to accept. We had directed Andrew back in April
> to write a hwmon driver for the chip, which he did.
>

Thanks Guenter,  I found the series

[PATCH v2 0/2] Add support for INA3221 Triple Current/Voltage Monitors
Looks fine to me. I can use the hwmon.

However, some of the stuff from my patch are not there which I will add later once original patch applied:
- Dynamic mode changes for continuous and one-shot from sysfs.
- In one shot, when try to read voltage data, do conversion and then read.

Not sure whether exporting the following will help or not. Can you please confirm?
- Oversampling time i.e. average sample
- conversion time for bus voltage and shunt voltage if default is not suited for system.