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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 22442C433F5 for ; Fri, 26 Nov 2021 12:31:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347891AbhKZMej (ORCPT ); Fri, 26 Nov 2021 07:34:39 -0500 Received: from mga09.intel.com ([134.134.136.24]:37544 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347215AbhKZMce (ORCPT ); Fri, 26 Nov 2021 07:32:34 -0500 X-IronPort-AV: E=McAfee;i="6200,9189,10179"; a="235478921" X-IronPort-AV: E=Sophos;i="5.87,265,1631602800"; d="scan'208";a="235478921" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Nov 2021 04:29:21 -0800 X-IronPort-AV: E=Sophos;i="5.87,265,1631602800"; d="scan'208";a="607851585" Received: from paasikivi.fi.intel.com ([10.237.72.42]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Nov 2021 04:29:19 -0800 Received: from paasikivi.fi.intel.com (localhost [127.0.0.1]) by paasikivi.fi.intel.com (Postfix) with ESMTP id 6306820165; Fri, 26 Nov 2021 14:28:47 +0200 (EET) Date: Fri, 26 Nov 2021 14:28:47 +0200 From: Sakari Ailus To: Martin Kepplinger Cc: mchehab@kernel.org, broonie@kernel.org, kernel@puri.sm, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-pm@vger.kernel.org, Angus Ainslie Subject: Re: [PATCH v2] media: i2c: dw9714: add optional regulator support Message-ID: References: <20211126090107.1243558-1-martin.kepplinger@puri.sm> <8d72c895ece6dce7d8badb241eebcbe076a03f81.camel@puri.sm> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <8d72c895ece6dce7d8badb241eebcbe076a03f81.camel@puri.sm> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 26, 2021 at 12:06:03PM +0100, Martin Kepplinger wrote: > Am Freitag, dem 26.11.2021 um 12:44 +0200 schrieb Sakari Ailus: > > Hi Martin, > > > > On Fri, Nov 26, 2021 at 10:01:07AM +0100, Martin Kepplinger wrote: > > > From: Angus Ainslie > > > > > > Allow the dw9714 to control a regulator and adjust suspend() and > > > resume() > > > to support both runtime and system pm. > > > > > > Signed-off-by: Angus Ainslie > > > Signed-off-by: Martin Kepplinger > > > --- > > > > > > revision history > > > ---------------- > > > > > > v2: (thank you Mark) > > >  * simplify the regulator_get_optional() error path > > >  * fix regulator usage during probe() > > > > > > v1: > > > https://lore.kernel.org/linux-media/20211125080922.978583-1-martin.kepplinger@puri.sm/ > > > > > > > > > > > >  drivers/media/i2c/dw9714.c | 39 > > > ++++++++++++++++++++++++++++++++++++++ > > >  1 file changed, 39 insertions(+) > > > > > > diff --git a/drivers/media/i2c/dw9714.c > > > b/drivers/media/i2c/dw9714.c > > > index 3863dfeb8293..e8cc19b89861 100644 > > > --- a/drivers/media/i2c/dw9714.c > > > +++ b/drivers/media/i2c/dw9714.c > > > @@ -5,6 +5,7 @@ > > >  #include > > >  #include > > >  #include > > > +#include > > >  #include > > >  #include > > >  #include > > > @@ -36,6 +37,7 @@ struct dw9714_device { > > >         struct v4l2_ctrl_handler ctrls_vcm; > > >         struct v4l2_subdev sd; > > >         u16 current_val; > > > +       struct regulator *vcc; > > >  }; > > >   > > >  static inline struct dw9714_device *to_dw9714_vcm(struct v4l2_ctrl > > > *ctrl) > > > @@ -145,6 +147,21 @@ static int dw9714_probe(struct i2c_client > > > *client) > > >         if (dw9714_dev == NULL) > > >                 return -ENOMEM; > > >   > > > +       dw9714_dev->vcc = devm_regulator_get_optional(&client->dev, > > > "vcc"); > > > > You you used regular devm_regulator_get(), you could remove the error > > handling below. If there's no regulator, you'll simply get a dummy > > one. > > ok thanks > > > > > > > +       if (IS_ERR(dw9714_dev->vcc)) { > > > +               dev_dbg(&client->dev, "No vcc regulator found: > > > %ld\n", > > > +                       PTR_ERR(dw9714_dev->vcc)); > > > +               dw9714_dev->vcc = NULL; > > > +       } > > > + > > > +       if (dw9714_dev->vcc) { > > > > With (dummy) regulators, these checks become unnecessary. > > > > > +               rval = regulator_enable(dw9714_dev->vcc); > > > +               if (rval < 0) { > > > +                       dev_err(&client->dev, "failed to enable > > > vcc: %d\n", rval); > > > +                       return rval; > > > +               } > > > +       } > > > + > > >         v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops); > > >         dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE | > > >                                 V4L2_SUBDEV_FL_HAS_EVENTS; > > > @@ -200,6 +217,9 @@ static int __maybe_unused > > > dw9714_vcm_suspend(struct device *dev) > > >         struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd); > > >         int ret, val; > > >   > > > +       if (pm_runtime_suspended(&client->dev)) > > > +               return 0; > > > > This can't take place in a runtime PM suspend callback. You'll need > > to add > > system suspend callback for this. > > but this function is both the system and runtime suspend callback. > doesn't splitting up the callbacks just add lines of code > unnecessarily? Hmm. After thinking about this a little, I think this could indeed work. Yeah, please leave it as-is. > > > > > > + > > >         for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - > > > 1); > > >              val >= 0; val -= DW9714_CTRL_STEPS) { > > >                 ret = dw9714_i2c_write(client, > > > @@ -208,6 +228,13 @@ static int __maybe_unused > > > dw9714_vcm_suspend(struct device *dev) > > >                         dev_err_once(dev, "%s I2C failure: %d", > > > __func__, ret); > > >                 usleep_range(DW9714_CTRL_DELAY_US, > > > DW9714_CTRL_DELAY_US + 10); > > >         } > > > + > > > +       if (dw9714_dev->vcc) { > > > +               ret = regulator_disable(dw9714_dev->vcc); > > > +               if (ret) > > > +                       dev_err(dev, "Failed to disable vcc: %d\n", > > > ret); > > > +       } > > > + > > >         return 0; > > >  } > > >   > > > @@ -224,6 +251,18 @@ static int  __maybe_unused > > > dw9714_vcm_resume(struct device *dev) > > >         struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd); > > >         int ret, val; > > >   > > > +       if (pm_runtime_suspended(&client->dev)) > > > > Same for this one. > > > > > +               return 0; > > > + > > > +       if (dw9714_dev->vcc) { > > > +               ret = regulator_enable(dw9714_dev->vcc); > > > +               if (ret) { > > > +                       dev_err(dev, "Failed to enable vcc: %d\n", > > > ret); > > > +                       return ret; > > > +               } > > > +               usleep_range(1000, 2000); > > > +       } > > > + > > >         for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS; > > >              val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1; > > >              val += DW9714_CTRL_STEPS) { > > > > -- Sakari Ailus