From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752429AbdEEJ4X (ORCPT ); Fri, 5 May 2017 05:56:23 -0400 Received: from mga03.intel.com ([134.134.136.65]:49258 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751170AbdEEJ4W (ORCPT ); Fri, 5 May 2017 05:56:22 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.38,292,1491289200"; d="scan'208";a="964773725" Message-ID: <1493978058.30052.26.camel@linux.intel.com> Subject: Re: [PATCH v3] iio: adc: Add support for TI ADC108S102 and ADC128S102 From: Andy Shevchenko To: Jan Kiszka , Jonathan Cameron Cc: linux-iio@vger.kernel.org, Linux Kernel Mailing List , Sascha Weisenberger , Mika Westerberg , Peter Meerwald-Stadler , Rob Herring Date: Fri, 05 May 2017 12:54:18 +0300 In-Reply-To: <6d6bf102-1bc9-7019-13fa-b8f86b002dc8@siemens.com> References: <6d6bf102-1bc9-7019-13fa-b8f86b002dc8@siemens.com> Organization: Intel Finland Oy Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.22.6-1 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2017-05-05 at 08:31 +0200, Jan Kiszka wrote: > This is an upstream port of an IIO driver for the TI ADC108S102 and > ADC128S102. The former can be found on the Intel Galileo Gen2 and the > Siemens SIMATIC IOT2000. For those boards, ACPI-based enumeration is > included. > > Due to the lack of regulators under ACPI, we need a special device > property to define the voltage provide to the VA pin of the ADC > ("va-millivolt"). For DT usage, the regulator "vref-supply" is > requested. Note that DT usage has not been tested. +1 to what Mika commented on this and just some additional information. Other than that looks pretty good. > Changes in v3: >  - Reworked reference voltage handling, splitting up the different > ACPI >    case from DT usage. This also means that the "va-millivolt" >    (formerly and incorrectly called "ext-vin-microvolt") becomes >    ACPI-only Just to be clean, there is *no* such thing as *XYZ-only* device properties. The idea behind them is to provide resource provider agnostic API to read properties. > + if (st->reg) > + *val = regulator_get_voltage(st->reg) > / 1000; > + else > + *val = st->va_millivolt; > + Another way is to not just hard code the value, but create a fixed voltage regulator out of it. In this case you will have one way to get its value. > + st->reg = devm_regulator_get(&spi->dev, "vref"); It should be _optional like I mentioned in one of previous review. > + if (!IS_ERR(st->reg)) This is redundant > + regulator_disable(st->reg); > + if (!IS_ERR(st->reg)) Ditto. > + regulator_disable(st->reg); -- Andy Shevchenko Intel Finland Oy