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=-7.1 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 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 4A618C43613 for ; Sat, 22 Jun 2019 09:23:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 207D32089C for ; Sat, 22 Jun 2019 09:23:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561195406; bh=8MdsXVlMi4vSBSz+Up33KUEB/PHAE+taEljjGpQ1cvo=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=pFD3pL2mPDMMoXwOb36ih7jh1uuY50GoMXliCepaYa8UA8bieAO5/PD3yyng/gsly ZgZlnI9EydU7ejB7hIKPhiVxWp+pGEI3ObUYC+XEaJPpqL+VJ1Fdi/Fmw8EboELYAL exTe4IqsOFe2Sk6zh+znKPxZIeSxK+6+MokjX8vk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726350AbfFVJXW (ORCPT ); Sat, 22 Jun 2019 05:23:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:32918 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726187AbfFVJXW (ORCPT ); Sat, 22 Jun 2019 05:23:22 -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 E8572206BA; Sat, 22 Jun 2019 09:23:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561195401; bh=8MdsXVlMi4vSBSz+Up33KUEB/PHAE+taEljjGpQ1cvo=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=ssmbRe9ttHQo0BO0o0UJlKAZDtHHdgGh4RQRJ3UeaAli22V7anbUE0Hu2y+O7Fruf OqzozYlIa/SB9yPtNZH5vGuKCugOXK4K0O4AXLUF0VjC72QrGY0xMpz9lOkEIM0PT8 nC9VS9JyFcfqATYAspQpwxBZcB6pqyndFRd4Cagw= Date: Sat, 22 Jun 2019 10:23:15 +0100 From: Jonathan Cameron To: Olivier Moysan Cc: , , , , , , , , , , Subject: Re: [PATCH 3/5] iio: adc: stm32-dfsdm: manage data resolution in trigger mode Message-ID: <20190622102315.2484d6de@archlinux> In-Reply-To: <1560949431-22948-4-git-send-email-olivier.moysan@st.com> References: <1560949431-22948-1-git-send-email-olivier.moysan@st.com> <1560949431-22948-4-git-send-email-olivier.moysan@st.com> X-Mailer: Claws Mail 3.17.3 (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 Wed, 19 Jun 2019 15:03:49 +0200 Olivier Moysan wrote: > Add output sample resolution management in scan mode. > Add stm32_dfsdm_process_data() function to share sample > processing between continuous and trigger modes. > > Signed-off-by: Olivier Moysan Makes sense, though I would have preferred a little bit more info on what the user visible effects fo this change are in the patch description. I think I know from reading the code, but not every one will do that ;) Applied to the togreg branch of iio.git and pushed out as testing for the autobuilders to play with it. Thanks, Jonathan > --- > drivers/iio/adc/stm32-dfsdm-adc.c | 41 ++++++++++++++++++++++++++------------- > 1 file changed, 28 insertions(+), 13 deletions(-) > > diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c > index 6b90a40882f2..5b19a88412a6 100644 > --- a/drivers/iio/adc/stm32-dfsdm-adc.c > +++ b/drivers/iio/adc/stm32-dfsdm-adc.c > @@ -779,6 +779,30 @@ static unsigned int stm32_dfsdm_adc_dma_residue(struct stm32_dfsdm_adc *adc) > return 0; > } > > +static inline void stm32_dfsdm_process_data(struct stm32_dfsdm_adc *adc, > + s32 *buffer) > +{ > + struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; > + struct stm32_dfsdm_filter_osr *flo = &fl->flo; > + unsigned int i = adc->nconv; > + s32 *ptr = buffer; > + > + while (i--) { > + /* Mask 8 LSB that contains the channel ID */ > + *ptr &= 0xFFFFFF00; > + /* Convert 2^(n-1) sample to 2^(n-1)-1 to avoid wrap-around */ > + if (*ptr > flo->max) > + *ptr -= 1; > + /* > + * Samples from filter are retrieved with 23 bits resolution > + * or less. Shift left to align MSB on 24 bits. > + */ > + *ptr <<= flo->lshift; > + > + ptr++; > + } > +} > + > static irqreturn_t stm32_dfsdm_adc_trigger_handler(int irq, void *p) > { > struct iio_poll_func *pf = p; > @@ -787,7 +811,9 @@ static irqreturn_t stm32_dfsdm_adc_trigger_handler(int irq, void *p) > int available = stm32_dfsdm_adc_dma_residue(adc); > > while (available >= indio_dev->scan_bytes) { > - u32 *buffer = (u32 *)&adc->rx_buf[adc->bufi]; > + s32 *buffer = (s32 *)&adc->rx_buf[adc->bufi]; > + > + stm32_dfsdm_process_data(adc, buffer); > > iio_push_to_buffers_with_timestamp(indio_dev, buffer, > pf->timestamp); > @@ -806,8 +832,6 @@ static void stm32_dfsdm_dma_buffer_done(void *data) > { > struct iio_dev *indio_dev = data; > struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); > - struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; > - struct stm32_dfsdm_filter_osr *flo = &fl->flo; > int available = stm32_dfsdm_adc_dma_residue(adc); > size_t old_pos; > > @@ -832,16 +856,7 @@ static void stm32_dfsdm_dma_buffer_done(void *data) > while (available >= indio_dev->scan_bytes) { > s32 *buffer = (s32 *)&adc->rx_buf[adc->bufi]; > > - /* Mask 8 LSB that contains the channel ID */ > - *buffer &= 0xFFFFFF00; > - /* Convert 2^(n-1) sample to 2^(n-1)-1 to avoid wrap-around */ > - if (*buffer > flo->max) > - *buffer -= 1; > - /* > - * Samples from filter are retrieved with 23 bits resolution > - * or less. Shift left to align MSB on 24 bits. > - */ > - *buffer <<= flo->lshift; > + stm32_dfsdm_process_data(adc, buffer); > > available -= indio_dev->scan_bytes; > adc->bufi += indio_dev->scan_bytes;