Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751457AbdISDL4 (ORCPT ); Mon, 18 Sep 2017 23:11:56 -0400 Received: from mail-out-2.itc.rwth-aachen.de ([134.130.5.47]:34641 "EHLO mail-out-2.itc.rwth-aachen.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751074AbdISDLy (ORCPT ); Mon, 18 Sep 2017 23:11:54 -0400 X-IronPort-AV: E=Sophos;i="5.42,415,1500933600"; d="scan'208";a="14000927" From: =?UTF-8?q?Stefan=20Br=C3=BCns?= To: CC: , Jonathan Cameron , Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler Subject: [PATCH 2/4] iio: light: vl6180: Avoid readback of integration time register Date: Tue, 19 Sep 2017 05:11:42 +0200 Message-ID: <20170919031144.4968-3-stefan.bruens@rwth-aachen.de> X-Mailer: git-send-email 2.14.1 In-Reply-To: <20170919031144.4968-1-stefan.bruens@rwth-aachen.de> References: <20170919031144.4968-1-stefan.bruens@rwth-aachen.de> MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-Originating-IP: [78.48.38.130] X-ClientProxiedBy: rwthex-s3-a.rwth-ad.de (2002:8682:1aa0::8682:1aa0) To rwthex-w2-a.rwth-ad.de (2002:8682:1a9e::8682:1a9e) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1594 Lines: 57 Instead of reading the value from the register on each query, store the set value. Signed-off-by: Stefan Brüns --- drivers/iio/light/vl6180.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/iio/light/vl6180.c b/drivers/iio/light/vl6180.c index 57577d5d18ac..ae768c832d66 100644 --- a/drivers/iio/light/vl6180.c +++ b/drivers/iio/light/vl6180.c @@ -86,6 +86,7 @@ struct vl6180_data { struct i2c_client *client; struct mutex lock; + unsigned int als_it_ms; }; enum { VL6180_ALS, VL6180_RANGE, VL6180_PROX }; @@ -306,13 +307,11 @@ static int vl6180_read_raw(struct iio_dev *indio_dev, return IIO_VAL_INT; case IIO_CHAN_INFO_INT_TIME: - ret = vl6180_read_word(data->client, VL6180_ALS_IT); - if (ret < 0) - return ret; - *val = 0; /* 1 count = 1ms (0 = 1ms) */ - *val2 = (ret + 1) * 1000; /* convert to seconds */ + *val = 0; + *val2 = data->als_it_ms * 1000; return IIO_VAL_INT_PLUS_MICRO; + case IIO_CHAN_INFO_SCALE: switch (chan->type) { case IIO_LIGHT: @@ -401,6 +400,9 @@ static int vl6180_set_it(struct vl6180_data *data, int val, int val2) ret = vl6180_write_word(data->client, VL6180_ALS_IT, it_ms - 1); + if (ret >= 0) + data->als_it_ms = it_ms; + fail: vl6180_hold(data, false); mutex_unlock(&data->lock); @@ -472,6 +474,7 @@ static int vl6180_init(struct vl6180_data *data) return ret; /* ALS integration time: 100ms */ + data->als_it_ms = 100; ret = vl6180_write_word(client, VL6180_ALS_IT, VL6180_ALS_IT_100); if (ret < 0) return ret; -- 2.14.1