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,USER_AGENT_SANE_2 autolearn=ham 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 A75A3C4332F for ; Sun, 8 Sep 2019 09:25:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 80F1D214D9 for ; Sun, 8 Sep 2019 09:25:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567934708; bh=PCTAy83waN3ZgE9Lk46050Vd0yttrDaO/Vn+ZQT+h+g=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=FOs+KlhO1SjBGyKVtxp34AN2SnjIMpUJ80SDeG8qGJimxSSm94XqzsYNv2s246D4D Jprca/wDY2WgFdvNz8N5GLvMF39EmXaUBqnWziu5KSfgFgt14rGCImsp8PRDQEKOH0 HZA8IIPlj8mhI6OLW+KExeoCwmX86UbBTW2WU/Hk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727748AbfIHJZE (ORCPT ); Sun, 8 Sep 2019 05:25:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:50640 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727608AbfIHJZE (ORCPT ); Sun, 8 Sep 2019 05:25:04 -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 663E520863; Sun, 8 Sep 2019 09:25:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567934703; bh=PCTAy83waN3ZgE9Lk46050Vd0yttrDaO/Vn+ZQT+h+g=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=YSKEmhtTLs+xsDKKy+f3CokAyyeMnOktDvQHiJwmlxpczkT5JazPpu+TUCdsF/Jq5 +tdNOVQdP185EAVZ4H42WOS9GRNnKqieWtoBLDs1F+uEmKsnLFFH58gc8EvrP+GKjD F85oWwxbK9oqbXGWqVVl8ZmQx3SLVLQjC2ySc4uU= Date: Sun, 8 Sep 2019 10:24:58 +0100 From: Jonathan Cameron To: Stefan Popa Cc: , , , , , Subject: Re: [PATCH 1/3] iio: accel: adxl372: Fix/remove limitation for FIFO samples Message-ID: <20190908102458.7ef6f1ed@archlinux> In-Reply-To: <1567502287-10199-1-git-send-email-stefan.popa@analog.com> References: <1567502287-10199-1-git-send-email-stefan.popa@analog.com> X-Mailer: Claws Mail 3.17.4 (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-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On Tue, 3 Sep 2019 12:18:07 +0300 Stefan Popa wrote: > Currently, the driver sets the FIFO_SAMPLES register with the number of > sample sets (maximum of 170 for 3 axis data, 256 for 2-axis and 512 for > single axis). However, the FIFO_SAMPLES register should store the number > of samples, regardless of how the FIFO format is configured. > > Signed-off-by: Stefan Popa This st->watermark field is also used to provide the hwfifo_watermark sysfs attribute value. That value should be 'sets' not individual samples. I'm not sure that's the case here. Note this also effects the max and min values which will change depending on which channels are enabled. I've just checked the docs and watermark is clearly stated to be in scans but the hwfifo_watermark is not. Which is unfortunate if there are drivers interpreting it as being in samples as a result. I haven't looked yet to see what other drivers have this interpreted as... Gah. Jonathan > --- > drivers/iio/accel/adxl372.c | 9 --------- > 1 file changed, 9 deletions(-) > > diff --git a/drivers/iio/accel/adxl372.c b/drivers/iio/accel/adxl372.c > index 055227cb..adec37b 100644 > --- a/drivers/iio/accel/adxl372.c > +++ b/drivers/iio/accel/adxl372.c > @@ -805,15 +805,6 @@ static int adxl372_buffer_postenable(struct iio_dev *indio_dev) > st->fifo_format = adxl372_axis_lookup_table[i].fifo_format; > st->fifo_set_size = bitmap_weight(indio_dev->active_scan_mask, > indio_dev->masklength); > - /* > - * The 512 FIFO samples can be allotted in several ways, such as: > - * 170 sample sets of concurrent 3-axis data > - * 256 sample sets of concurrent 2-axis data (user selectable) > - * 512 sample sets of single-axis data > - */ > - if ((st->watermark * st->fifo_set_size) > ADXL372_FIFO_SIZE) > - st->watermark = (ADXL372_FIFO_SIZE / st->fifo_set_size); > - > st->fifo_mode = ADXL372_FIFO_STREAMED; > > ret = adxl372_configure_fifo(st);