Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755486AbdLUSdm (ORCPT ); Thu, 21 Dec 2017 13:33:42 -0500 Received: from mail-out-2.itc.rwth-aachen.de ([134.130.5.47]:18819 "EHLO mail-out-2.itc.rwth-aachen.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752522AbdLUSbx (ORCPT ); Thu, 21 Dec 2017 13:31:53 -0500 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: =?us-ascii?q?A2AYCgB8/Tta/54agoZbHAEBAQQBAQoBA?= =?us-ascii?q?YM+ZoEbB4N/mTSBWpllCiWER08ChEpDFAEBAQEBAQEBAWsohSQGIwQLAUYQJQI?= =?us-ascii?q?mAgJXBg4FiisEDKQ4gW06iFOCHAEBAQEBAQQBAQEBASMJAYEFgnCCEoM/KQyGK?= =?us-ascii?q?YFSEVeCDgwxgmUFik6YeoEThm6PRYl8KYc+jSGJMQICAgIJAhqBOzYigU9wgnk?= =?us-ascii?q?JhE93iQEBgRUBAQE?= X-IPAS-Result: =?us-ascii?q?A2AYCgB8/Tta/54agoZbHAEBAQQBAQoBAYM+ZoEbB4N/mTS?= =?us-ascii?q?BWpllCiWER08ChEpDFAEBAQEBAQEBAWsohSQGIwQLAUYQJQImAgJXBg4FiisED?= =?us-ascii?q?KQ4gW06iFOCHAEBAQEBAQQBAQEBASMJAYEFgnCCEoM/KQyGKYFSEVeCDgwxgmU?= =?us-ascii?q?Fik6YeoEThm6PRYl8KYc+jSGJMQICAgIJAhqBOzYigU9wgnkJhE93iQEBgRUBA?= =?us-ascii?q?QE?= X-IronPort-AV: E=Sophos;i="5.45,437,1508796000"; d="scan'208";a="30601173" From: =?UTF-8?q?Stefan=20Br=C3=BCns?= To: CC: Peter Meerwald-Stadler , =?UTF-8?q?Stefan=20Br=C3=BCns?= , Maciej Purski , , "Andrew F . Davis" , Lars-Peter Clausen , Jonathan Cameron , Hartmut Knaack Subject: [PATCH v2 3/7] iio: adc: ina2xx: Remove unneeded dummy read to clear CNVR flag Date: Thu, 21 Dec 2017 19:31:34 +0100 X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171221183138.361-1-stefan.bruens@rwth-aachen.de> References: <20171221183138.361-1-stefan.bruens@rwth-aachen.de> MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-Originating-IP: [92.228.148.100] X-ClientProxiedBy: rwthex-s1-a.rwth-ad.de (2002:8682:1a98::8682:1a98) To rwthex-w2-a.rwth-ad.de (2002:8682:1a9e::8682:1a9e) Message-ID: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1594 Lines: 56 Although the datasheet states the CNVR flag is cleared by reading the BUS_VOLTAGE register, it is actually cleared by reading any of the voltage/current/power registers. The behaviour has been confirmed by TI support: http://e2e.ti.com/support/amplifiers/current-shunt-monitors/f/931/p/647053/2378282 Signed-off-by: Stefan Brüns --- Changes in v2: None drivers/iio/adc/ina2xx-adc.c | 14 -------------- 1 file changed, 14 deletions(-) diff --git a/drivers/iio/adc/ina2xx-adc.c b/drivers/iio/adc/ina2xx-adc.c index 8c8120406f52..b027d485398b 100644 --- a/drivers/iio/adc/ina2xx-adc.c +++ b/drivers/iio/adc/ina2xx-adc.c @@ -705,7 +705,6 @@ static int ina2xx_work_buffer(struct iio_dev *indio_dev) int bit, ret, i = 0; s64 time_a, time_b; unsigned int alert; - int cnvr_need_clear = 0; time_a = iio_get_time_ns(indio_dev); @@ -730,7 +729,6 @@ static int ina2xx_work_buffer(struct iio_dev *indio_dev) ret = regmap_read(chip->regmap, INA2XX_BUS_VOLTAGE, &alert); alert &= INA219_CNVR; - cnvr_need_clear = alert; } if (ret < 0) @@ -752,18 +750,6 @@ static int ina2xx_work_buffer(struct iio_dev *indio_dev) return ret; data[i++] = val; - - if (INA2XX_SHUNT_VOLTAGE + bit == INA2XX_POWER) - cnvr_need_clear = 0; - } - - /* Dummy read on INA219 power register to clear CNVR flag */ - if (cnvr_need_clear && chip->config->chip_id == ina219) { - unsigned int val; - - ret = regmap_read(chip->regmap, INA2XX_POWER, &val); - if (ret < 0) - return ret; } time_b = iio_get_time_ns(indio_dev); -- 2.15.1