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 5E151C433DF for ; Sun, 24 May 2020 13:09:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 34D8120823 for ; Sun, 24 May 2020 13:09:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590325765; bh=2Yhi6AKFxMkREcrMyAjTyEAf6Iw0DqTol3b+5FGWzSs=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=jrUrhp8VOKGW48nNndcwiyt0lGao7usloT9vQFMABgWWgNpWNQgByRL6vYDujx4RB 6LIxlEHyd3lK9zBsVAqy215CIVtTIipkdKLFEbMkSU7+VuOMkc5UoT8aSTt8tWN5Z0 CiA09ghmHi5yzVU10h0RgVTh3GBp9Q7eicSKlTac= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728619AbgEXNJY (ORCPT ); Sun, 24 May 2020 09:09:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:54102 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726064AbgEXNJY (ORCPT ); Sun, 24 May 2020 09:09:24 -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 3F90C20787; Sun, 24 May 2020 13:09:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590325763; bh=2Yhi6AKFxMkREcrMyAjTyEAf6Iw0DqTol3b+5FGWzSs=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=iWZTut5b8mxLNhLlCnMOxg/R8R2+jNVX9r8MLjATtcpik9eWu58nOyjiWkTIQMpsm PZ+70RsULak+qQgaOZEZWwEhK+yyxrOt/BvYWCNtGrI3VU8Cb4QjPS1deZvTckyiHi 3jNksUCj8e2rkha0ulieGFwr8G1SGc6AiqaAXuj0= Date: Sun, 24 May 2020 14:09:19 +0100 From: Jonathan Cameron To: Alexandru Ardelean Cc: , , , , , Subject: Re: [PATCH] iio: stm32-adc: keep a reference to the iio device on the state struct Message-ID: <20200524140919.30b63227@archlinux> In-Reply-To: <20200522130719.630714-1-alexandru.ardelean@analog.com> References: <20200522130719.630714-1-alexandru.ardelean@analog.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-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On Fri, 22 May 2020 16:07:19 +0300 Alexandru Ardelean wrote: > We may want to get rid of the iio_priv_to_dev() helper. The reason is that > we will hide some of the members of the iio_dev structure (to prevent > drivers from accessing them directly), and that will also mean hiding the > implementation of the iio_priv_to_dev() helper inside the IIO core. > > Hiding the implementation of iio_priv_to_dev() implies that some fast-paths > may not be fast anymore, so a general idea is to try to get rid of the > iio_priv_to_dev() altogether. > The iio_priv() helper won't be affected by the rework. > > For this driver, not using iio_priv_to_dev(), means keeping a reference to > the IIO device on the state struct. > > Signed-off-by: Alexandru Ardelean I don't particularly mind this approach, but an alternative would be to change the callbacks to take an iio_dev rather than the iio_priv() structure. It's more invasive though as need to change what is provided via dev_get_drvdata for the adc device. It's possible I missed a path where this won't work for some reason though. Up to the driver maintainers on which one they prefer. Thanks, Jonathan > --- > drivers/iio/adc/stm32-adc.c | 27 +++++++++++++++------------ > 1 file changed, 15 insertions(+), 12 deletions(-) > > diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c > index ae622ee6d08c..7e58c4443e3f 100644 > --- a/drivers/iio/adc/stm32-adc.c > +++ b/drivers/iio/adc/stm32-adc.c > @@ -171,6 +171,7 @@ struct stm32_adc_cfg { > > /** > * struct stm32_adc - private data of each ADC IIO instance > + * @indio_dev: back-reference to the IIO device object > * @common: reference to ADC block common data > * @offset: ADC instance register offset in ADC block > * @cfg: compatible configuration data > @@ -194,6 +195,7 @@ struct stm32_adc_cfg { > * @chan_name: channel name array > */ > struct stm32_adc { > + struct iio_dev *indio_dev; > struct stm32_adc_common *common; > u32 offset; > const struct stm32_adc_cfg *cfg; > @@ -637,7 +639,7 @@ static void stm32h7_adc_start_conv(struct stm32_adc *adc, bool dma) > > static void stm32h7_adc_stop_conv(struct stm32_adc *adc) > { > - struct iio_dev *indio_dev = iio_priv_to_dev(adc); > + struct iio_dev *indio_dev = adc->indio_dev; > int ret; > u32 val; > > @@ -654,7 +656,7 @@ static void stm32h7_adc_stop_conv(struct stm32_adc *adc) > > static int stm32h7_adc_exit_pwr_down(struct stm32_adc *adc) > { > - struct iio_dev *indio_dev = iio_priv_to_dev(adc); > + struct iio_dev *indio_dev = adc->indio_dev; > int ret; > u32 val; > > @@ -692,7 +694,7 @@ static void stm32h7_adc_enter_pwr_down(struct stm32_adc *adc) > > static int stm32h7_adc_enable(struct stm32_adc *adc) > { > - struct iio_dev *indio_dev = iio_priv_to_dev(adc); > + struct iio_dev *indio_dev = adc->indio_dev; > int ret; > u32 val; > > @@ -715,7 +717,7 @@ static int stm32h7_adc_enable(struct stm32_adc *adc) > > static void stm32h7_adc_disable(struct stm32_adc *adc) > { > - struct iio_dev *indio_dev = iio_priv_to_dev(adc); > + struct iio_dev *indio_dev = adc->indio_dev; > int ret; > u32 val; > > @@ -735,7 +737,7 @@ static void stm32h7_adc_disable(struct stm32_adc *adc) > */ > static int stm32h7_adc_read_selfcalib(struct stm32_adc *adc) > { > - struct iio_dev *indio_dev = iio_priv_to_dev(adc); > + struct iio_dev *indio_dev = adc->indio_dev; > int i, ret; > u32 lincalrdyw_mask, val; > > @@ -779,7 +781,7 @@ static int stm32h7_adc_read_selfcalib(struct stm32_adc *adc) > */ > static int stm32h7_adc_restore_selfcalib(struct stm32_adc *adc) > { > - struct iio_dev *indio_dev = iio_priv_to_dev(adc); > + struct iio_dev *indio_dev = adc->indio_dev; > int i, ret; > u32 lincalrdyw_mask, val; > > @@ -852,7 +854,7 @@ static int stm32h7_adc_restore_selfcalib(struct stm32_adc *adc) > */ > static int stm32h7_adc_selfcalib(struct stm32_adc *adc) > { > - struct iio_dev *indio_dev = iio_priv_to_dev(adc); > + struct iio_dev *indio_dev = adc->indio_dev; > int ret; > u32 val; > > @@ -1228,7 +1230,7 @@ static int stm32_adc_read_raw(struct iio_dev *indio_dev, > static irqreturn_t stm32_adc_threaded_isr(int irq, void *data) > { > struct stm32_adc *adc = data; > - struct iio_dev *indio_dev = iio_priv_to_dev(adc); > + struct iio_dev *indio_dev = adc->indio_dev; > const struct stm32_adc_regspec *regs = adc->cfg->regs; > u32 status = stm32_adc_readl(adc, regs->isr_eoc.reg); > > @@ -1241,7 +1243,7 @@ static irqreturn_t stm32_adc_threaded_isr(int irq, void *data) > static irqreturn_t stm32_adc_isr(int irq, void *data) > { > struct stm32_adc *adc = data; > - struct iio_dev *indio_dev = iio_priv_to_dev(adc); > + struct iio_dev *indio_dev = adc->indio_dev; > const struct stm32_adc_regspec *regs = adc->cfg->regs; > u32 status = stm32_adc_readl(adc, regs->isr_eoc.reg); > > @@ -1879,6 +1881,7 @@ static int stm32_adc_probe(struct platform_device *pdev) > return -ENOMEM; > > adc = iio_priv(indio_dev); > + adc->indio_dev = indio_dev; > adc->common = dev_get_drvdata(pdev->dev.parent); > spin_lock_init(&adc->lock); > init_completion(&adc->completion); > @@ -1990,7 +1993,7 @@ static int stm32_adc_probe(struct platform_device *pdev) > static int stm32_adc_remove(struct platform_device *pdev) > { > struct stm32_adc *adc = platform_get_drvdata(pdev); > - struct iio_dev *indio_dev = iio_priv_to_dev(adc); > + struct iio_dev *indio_dev = adc->indio_dev; > > pm_runtime_get_sync(&pdev->dev); > iio_device_unregister(indio_dev); > @@ -2013,7 +2016,7 @@ static int stm32_adc_remove(struct platform_device *pdev) > static int stm32_adc_suspend(struct device *dev) > { > struct stm32_adc *adc = dev_get_drvdata(dev); > - struct iio_dev *indio_dev = iio_priv_to_dev(adc); > + struct iio_dev *indio_dev = adc->indio_dev; > > if (iio_buffer_enabled(indio_dev)) > __stm32_adc_buffer_predisable(indio_dev); > @@ -2024,7 +2027,7 @@ static int stm32_adc_suspend(struct device *dev) > static int stm32_adc_resume(struct device *dev) > { > struct stm32_adc *adc = dev_get_drvdata(dev); > - struct iio_dev *indio_dev = iio_priv_to_dev(adc); > + struct iio_dev *indio_dev = adc->indio_dev; > int ret; > > ret = pm_runtime_force_resume(dev);