From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laxman Dewangan Subject: Re: [PATCH V4 2/2] thermal: generic-adc: Add ADC based thermal sensor driver Date: Thu, 21 Apr 2016 06:42:16 +0530 Message-ID: <571828F0.8000101@nvidia.com> References: <1461050521-6080-1-git-send-email-ldewangan@nvidia.com> <1461050521-6080-2-git-send-email-ldewangan@nvidia.com> <20160420234322.GA2558@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20160420234322.GA2558-bi+AKbBUZKY6gyzm1THtWbp2dZbC/Bob@public.gmane.org> Sender: linux-iio-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Eduardo Valentin Cc: jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, rui.zhang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org, pawel.moll-5wv7dgnIgG8@public.gmane.org, ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg@public.gmane.org, linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-iio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org On Thursday 21 April 2016 05:13 AM, Eduardo Valentin wrote: > Laxman, > > On Tue, Apr 19, 2016 at 12:52:01PM +0530, Laxman Dewangan wrote: >> In some of platform, thermal sensors like NCT thermistors are >> connected to the one of ADC channel. The temperature is read by >> reading the voltage across the sensor resistance via ADC. Lookup >> table for ADC read value to temperature is referred to get >> temperature. ADC is read via IIO framework. >> >> Add support for thermal sensor driver which read the voltage across >> sensor resistance from ADC through IIO framework. >> >> Signed-off-by: Laxman Dewangan > I really like this driver, as I mentioned before. Just one comment > though. > >> + >> + gti->tz_dev = thermal_zone_of_sensor_register(&pdev->dev, 0, >> + gti, &gadc_thermal_ops); > Why not using the devm_ version you introduced? > > Any particular reason? > Yaah, the reason is just to maintain the proper sequence in releasing of resource during driver unbinding. Sequence in probe are: iio_channel_get() thermal_zone_of_sensor_register() and on release, sensor should be released first before iio channel. As of now, we do not have devm_iio_channel_get() [I already post patch and it is accepted by Jonathan in iio sub system] and hence I can not use the devm_ for sensor register to avoid race. However, once the devm_ for iio channel get available in all subsystem (may be in next release), I will post the patch to use devm_. Currently, we can go with these APIs.