From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753157AbdKVWnJ (ORCPT ); Wed, 22 Nov 2017 17:43:09 -0500 Received: from omzsmtpe01.verizonbusiness.com ([199.249.25.210]:13432 "EHLO omzsmtpe01.verizonbusiness.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753091AbdKVW1t (ORCPT ); Wed, 22 Nov 2017 17:27:49 -0500 From: alexander.levin@verizon.com Cc: Ladislav Michl , Daniel Baluta , Jonathan Cameron , "Jonathan Cameron" , alexander.levin@verizon.com X-Host: mariner.tdc.vzwcorp.com To: "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" Subject: [PATCH AUTOSEL for 4.14 50/51] iio: adc: ti-ads1015: add 10% to conversion wait time Thread-Topic: [PATCH AUTOSEL for 4.14 50/51] iio: adc: ti-ads1015: add 10% to conversion wait time Thread-Index: AQHTY+DY+ukPspwuSEC9Ki1YhdLNSQ== Date: Wed, 22 Nov 2017 22:25:48 +0000 Message-ID: <20171122222526.20021-50-alexander.levin@verizon.com> References: <20171122222526.20021-1-alexander.levin@verizon.com> In-Reply-To: <20171122222526.20021-1-alexander.levin@verizon.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-messagesentrepresentingtype: 1 x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.144.60.250] Content-Type: text/plain; charset="utf-8" Content-ID: <771E8046E64EEB4CA8CFB3D1CA837104@vzwcorp.com> MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by nfs id vAMMhEXY026792 From: Ladislav Michl [ Upstream commit fe895ac88b9fbdf2026f0bfd56c82747bb9d7c48 ] As user's guide "ADS1015EVM, ADS1115EVM, ADS1015EVM-PDK, ADS1115EVM-PDK User Guide (Rev. B)" (http://www.ti.com/lit/ug/sbau157b/sbau157b.pdf) states at page 16: "Note that both the ADS1115 and ADS1015 have internal clocks with a ±10% accuracy. If performing FFT tests, frequencies may appear to be incorrect as a result of this tolerance range.", add those 10% to converion wait time. Cc: Daniel Baluta Cc: Jonathan Cameron Signed-off-by: Ladislav Michl Reviewed-by: Akinobu Mita Signed-off-by: Jonathan Cameron Signed-off-by: Sasha Levin --- drivers/iio/adc/ti-ads1015.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/iio/adc/ti-ads1015.c b/drivers/iio/adc/ti-ads1015.c index e0dc20488335..9ac2fb032df6 100644 --- a/drivers/iio/adc/ti-ads1015.c +++ b/drivers/iio/adc/ti-ads1015.c @@ -369,6 +369,7 @@ int ads1015_get_adc_result(struct ads1015_data *data, int chan, int *val) conv_time = DIV_ROUND_UP(USEC_PER_SEC, data->data_rate[dr_old]); conv_time += DIV_ROUND_UP(USEC_PER_SEC, data->data_rate[dr]); + conv_time += conv_time / 10; /* 10% internal clock inaccuracy */ usleep_range(conv_time, conv_time + 1); data->conv_invalid = false; } -- 2.11.0