From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from saturn.retrosnub.co.uk ([178.18.118.26]:47003 "EHLO saturn.retrosnub.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753433AbbGSMdj (ORCPT ); Sun, 19 Jul 2015 08:33:39 -0400 Message-ID: <55AB9922.2020104@kernel.org> Date: Sun, 19 Jul 2015 13:33:38 +0100 From: Jonathan Cameron MIME-Version: 1.0 To: Hartmut Knaack , Andrea Galbusera CC: linux-iio@vger.kernel.org Subject: Re: [PATCH 1/4] iio: adc: mcp320x: add masking of unknown bits References: <1436880983-29017-1-git-send-email-gizero@gmail.com> <55A6A295.9020102@gmx.de> In-Reply-To: <55A6A295.9020102@gmx.de> Content-Type: text/plain; charset=windows-1252 Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org On 15/07/15 19:12, Hartmut Knaack wrote: > Andrea Galbusera schrieb am 14.07.2015 um 15:36: >> According to the datasheet, the 2 MSBs for parts 3001 and 3201 are >> unspecified and should be masked out >> > > Hi, > since resolution is already set, better make it more generic by applying > the mask in _read_raw like this: > > *val = ret & GENMASK(adc->chip_info->resolution - 1, 0); > > Thanks, > Hartmut Agreed, that would be cleaner. > >> Signed-off-by: Andrea Galbusera >> --- >> >> This was already suggested but for some reason got lost during review of a >> previous patch. See http://marc.info/?l=linux-iio&m=140748835509583&w=2 >> and following discussion >> >> drivers/iio/adc/mcp320x.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/iio/adc/mcp320x.c b/drivers/iio/adc/mcp320x.c >> index 8d9c9b9..0673ee7 100644 >> --- a/drivers/iio/adc/mcp320x.c >> +++ b/drivers/iio/adc/mcp320x.c >> @@ -114,13 +114,13 @@ static int mcp320x_adc_conversion(struct mcp320x *adc, u8 channel, >> >> switch (device_index) { >> case mcp3001: >> - return (adc->rx_buf[0] << 5 | adc->rx_buf[1] >> 3); >> + return ((adc->rx_buf[0] & 0x1f) << 5 | adc->rx_buf[1] >> 3); >> case mcp3002: >> case mcp3004: >> case mcp3008: >> return (adc->rx_buf[0] << 2 | adc->rx_buf[1] >> 6); >> case mcp3201: >> - return (adc->rx_buf[0] << 7 | adc->rx_buf[1] >> 1); >> + return ((adc->rx_buf[0] & 0x1f) << 7 | adc->rx_buf[1] >> 1); >> case mcp3202: >> case mcp3204: >> case mcp3208: >> > > -- > To unsubscribe from this list: send the line "unsubscribe linux-iio" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >