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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 51567C4338F for ; Fri, 6 Aug 2021 09:59:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 32A2860ED6 for ; Fri, 6 Aug 2021 09:59:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244815AbhHFKAB (ORCPT ); Fri, 6 Aug 2021 06:00:01 -0400 Received: from gloria.sntech.de ([185.11.138.130]:33294 "EHLO gloria.sntech.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244796AbhHFJ77 (ORCPT ); Fri, 6 Aug 2021 05:59:59 -0400 Received: from ip5f5aa64a.dynamic.kabel-deutschland.de ([95.90.166.74] helo=diego.localnet) by gloria.sntech.de with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1mBwdf-0003ST-9D; Fri, 06 Aug 2021 11:59:39 +0200 From: Heiko =?ISO-8859-1?Q?St=FCbner?= To: Jonathan Cameron , Simon Xue Cc: linux-rockchip@lists.infradead.org, devicetree@vger.kernel.org, robh+dt@kernel.org, Johan Jonker , Lars-Peter Clausen , Peter Meerwald-Stadler , linux-iio@vger.kernel.org, David Wu , Simon Xue Subject: Re: [PATCH v1] iio: adc: rockchip_saradc: just get referenced voltage once at probe Date: Fri, 06 Aug 2021 11:59:38 +0200 Message-ID: <2090286.yIU609i1g2@diego> In-Reply-To: <20210806080244.223907-1-xxm@rock-chips.com> References: <20210806080244.223907-1-xxm@rock-chips.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi Simon, Am Freitag, 6. August 2021, 10:02:44 CEST schrieb Simon Xue: > From: David Wu > > Add voltage notifier, no need to query regulator voltage for > every saradc read, just get regulator voltage once at probe. > > Signed-off-by: Simon Xue > Signed-off-by: David Wu thanks for picking up the suggestion for the regulator notifier :-) . Please also adapt the commit message to include that information though and please also increase the versioning ... this definitly isn't v1 ;-) . One more thing down below. > --- > drivers/iio/adc/rockchip_saradc.c | 35 ++++++++++++++++++++++++------- > 1 file changed, 28 insertions(+), 7 deletions(-) > > diff --git a/drivers/iio/adc/rockchip_saradc.c b/drivers/iio/adc/rockchip_saradc.c > index f3eb8d2e50dc..d8b0954aeb43 100644 > --- a/drivers/iio/adc/rockchip_saradc.c > +++ b/drivers/iio/adc/rockchip_saradc.c > @@ -49,10 +49,12 @@ struct rockchip_saradc { > struct clk *clk; > struct completion completion; > struct regulator *vref; > + int uv_vref; > struct reset_control *reset; > const struct rockchip_saradc_data *data; > u16 last_val; > const struct iio_chan_spec *last_chan; > + struct notifier_block nb; > }; > > static void rockchip_saradc_power_down(struct rockchip_saradc *info) > @@ -105,13 +107,7 @@ static int rockchip_saradc_read_raw(struct iio_dev *indio_dev, > mutex_unlock(&indio_dev->mlock); > return IIO_VAL_INT; > case IIO_CHAN_INFO_SCALE: > - ret = regulator_get_voltage(info->vref); > - if (ret < 0) { > - dev_err(&indio_dev->dev, "failed to get voltage\n"); > - return ret; > - } > - > - *val = ret / 1000; > + *val = info->uv_vref / 1000; > *val2 = chan->scan_type.realbits; > return IIO_VAL_FRACTIONAL_LOG2; > default: > @@ -298,6 +294,19 @@ static irqreturn_t rockchip_saradc_trigger_handler(int irq, void *p) > return IRQ_HANDLED; > } > > +static int rockchip_saradc_volt_notify(struct notifier_block *nb, > + unsigned long event, > + void *data) > +{ > + struct rockchip_saradc *info = > + container_of(nb, struct rockchip_saradc, nb); > + > + if (event & REGULATOR_EVENT_VOLTAGE_CHANGE) > + info->uv_vref = (unsigned long)data; > + > + return NOTIFY_OK; > +} > + You probably want an devm-action to unregister the notifier on device removal. Something like this and the addition in _probe(). static void rockchip_saradc_regulator_action(void *data) { struct rockchip_saradc *info = data; regulator_unregister_notifier(info->vref, &info->nb); } > static int rockchip_saradc_probe(struct platform_device *pdev) > { > struct rockchip_saradc *info = NULL; > @@ -410,6 +419,13 @@ static int rockchip_saradc_probe(struct platform_device *pdev) > return ret; > } > > + info->uv_vref = regulator_get_voltage(info->vref); > + if (info->uv_vref < 0) { > + dev_err(&pdev->dev, "failed to get voltage\n"); > + ret = info->uv_vref; > + return ret; > + } > + > ret = clk_prepare_enable(info->pclk); > if (ret < 0) { > dev_err(&pdev->dev, "failed to enable pclk\n"); > @@ -450,6 +466,11 @@ static int rockchip_saradc_probe(struct platform_device *pdev) > if (ret) > return ret; > > + info->nb.notifier_call = rockchip_saradc_volt_notify; > + ret = regulator_register_notifier(info->vref, &info->nb); > + if (ret) > + return ret; > + ret = devm_add_action_or_reset(&pdev->dev, rockchip_saradc_regulator_action, info); if (ret) goto ret; This ties the unregistration nicely into the devm-framework and thus doesn't require any additional error handling, as the "action" is also directly called if devm_add_action fails. Heiko > return devm_iio_device_register(&pdev->dev, indio_dev); > } > >