From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 111BBC3A5A0 for ; Sat, 18 Apr 2020 15:06:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E5BB421D6C for ; Sat, 18 Apr 2020 15:06:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587222374; bh=WSSh4VYHIuXqS25vztwkH7Z0icJIFqorESdXxBszA/Y=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=0HuXSNHdrwTZYcA8xWKciSPkWXpVYgOAoVyAYAYQj99ShrJvN+4+QPDwuAqeynllG 17VLy7FNlc80OOaUrarQJtx34Twe0Z6Mmmyo5tTr0E9Z00pBKJ2e5BkLEExEqGPc3u C84NOCZ6/54ZdPrVA44GuI430gjhE7NkOjqYCsGM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726505AbgDRPGO (ORCPT ); Sat, 18 Apr 2020 11:06:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:41642 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725903AbgDRPGN (ORCPT ); Sat, 18 Apr 2020 11:06:13 -0400 Received: from archlinux (cpc149474-cmbg20-2-0-cust94.5-4.cable.virginm.net [82.4.196.95]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C2AA42076A; Sat, 18 Apr 2020 15:06:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587222373; bh=WSSh4VYHIuXqS25vztwkH7Z0icJIFqorESdXxBszA/Y=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=mfvJmDye3Fg0GYmcb8DGBu8CgrjFGuIGzOVuiVZIbjxX04w1Yry3WSUHv8/wHMg4o NdeWO5t7yRzeg3BBuOXJsc2BQfebtaDlxk4KTaIk3PGC7929vRXCtDm5UYSKXjvzMg bBTQVMVF6JB9EIEXzIXBp2Bs8dlhmReFMfEzhYsM= Date: Sat, 18 Apr 2020 16:06:08 +0100 From: Jonathan Cameron To: Alexandre Belloni Cc: Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , Gregory CLEMENT , linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 1/2] iio: adc: ti-ads8344: properly byte swap value Message-ID: <20200418160608.55046663@archlinux> In-Reply-To: <20200416205428.437503-2-alexandre.belloni@bootlin.com> References: <20200416205428.437503-1-alexandre.belloni@bootlin.com> <20200416205428.437503-2-alexandre.belloni@bootlin.com> X-Mailer: Claws Mail 3.17.5 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 16 Apr 2020 22:54:27 +0200 Alexandre Belloni wrote: > The first received byte is the MSB, followed by the LSB so the value needs > to be byte swapped. > > Also, the ADC actually has a delay of one clock on the SPI bus. Read three > bytes to get the last bit. > > Fixes: 8dd2d7c0fed7 ("iio: adc: Add driver for the TI ADS8344 A/DC chips") > Signed-off-by: Alexandre Belloni Applied to the fixes-togreg branch of iio.git. Marked for stable. Random aside that I'll probably forget to clean up. Driver includes iio/buffer.h and doesn't use it... Thanks, Jonathan > --- > drivers/iio/adc/ti-ads8344.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/iio/adc/ti-ads8344.c b/drivers/iio/adc/ti-ads8344.c > index 9a460807d46d..abe4b56c847c 100644 > --- a/drivers/iio/adc/ti-ads8344.c > +++ b/drivers/iio/adc/ti-ads8344.c > @@ -29,7 +29,7 @@ struct ads8344 { > struct mutex lock; > > u8 tx_buf ____cacheline_aligned; > - u16 rx_buf; > + u8 rx_buf[3]; > }; > > #define ADS8344_VOLTAGE_CHANNEL(chan, si) \ > @@ -89,11 +89,11 @@ static int ads8344_adc_conversion(struct ads8344 *adc, int channel, > > udelay(9); > > - ret = spi_read(spi, &adc->rx_buf, 2); > + ret = spi_read(spi, adc->rx_buf, sizeof(adc->rx_buf)); > if (ret) > return ret; > > - return adc->rx_buf; > + return adc->rx_buf[0] << 9 | adc->rx_buf[1] << 1 | adc->rx_buf[2] >> 7; > } > > static int ads8344_read_raw(struct iio_dev *iio,