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 4C166C352A6 for ; Wed, 16 Dec 2020 18:26:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0C3F324B9C for ; Wed, 16 Dec 2020 18:26:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730551AbgLPSZx (ORCPT ); Wed, 16 Dec 2020 13:25:53 -0500 Received: from honk.sigxcpu.org ([24.134.29.49]:45208 "EHLO honk.sigxcpu.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730503AbgLPSZv (ORCPT ); Wed, 16 Dec 2020 13:25:51 -0500 Received: from localhost (localhost [127.0.0.1]) by honk.sigxcpu.org (Postfix) with ESMTP id CE92FFB03; Wed, 16 Dec 2020 19:25:07 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at honk.sigxcpu.org Received: from honk.sigxcpu.org ([127.0.0.1]) by localhost (honk.sigxcpu.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id cqkJ8AbYKf6s; Wed, 16 Dec 2020 19:25:06 +0100 (CET) Received: by bogon.sigxcpu.org (Postfix, from userid 1000) id F0ED143FDC; Wed, 16 Dec 2020 19:25:05 +0100 (CET) Date: Wed, 16 Dec 2020 19:25:05 +0100 From: Guido =?iso-8859-1?Q?G=FCnther?= To: Lucas Stach Cc: Kishon Vijay Abraham I , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , NXP Linux Team , Robert Chiras , Sam Ravnborg , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2 1/1] phy: fsl-imx8-mipi-dphy: Hook into runtime pm Message-ID: <20201216182505.GA51879@bogon.m.sigxcpu.org> References: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Lucas, On Wed, Dec 16, 2020 at 01:05:36PM +0100, Lucas Stach wrote: > Hi Guido, > > this time hopefully with less broken quoting. My mailer is driving me > mad right now... > > Am Mittwoch, dem 16.12.2020 um 12:27 +0100 schrieb Guido Günther: > > This allows us to shut down the mipi power domain on the imx8. The > > alternative would be to drop the dphy from the mipi power domain in the > > SOCs device tree and only have the DSI host controller visible there but > > since the PD is mostly about the PHY that would defeat it's purpose. > > Adding RPM support is exactly the right course of action. Thanks for confirming! > > > This allows to shut off the power domain hen blanking the LCD panel: > > > > pm_genpd_summary before: > > > > domain status slaves > >     /device runtime status > > ---------------------------------------------------------------------- > > mipi on > >     /devices/platform/soc@0/soc@0:bus@30800000/30a00300.dphy unsupported > >     /devices/platform/soc@0/soc@0:bus@30800000/30a00000.mipi_dsi suspended > > > > after: > > > > mipi off-0 > >     /devices/platform/soc@0/soc@0:bus@30800000/30a00300.dphy suspended > >     /devices/platform/soc@0/soc@0:bus@30800000/30a00000.mipi_dsi suspended > > > > Signed-off-by: Guido Günther > > --- > >  .../phy/freescale/phy-fsl-imx8-mipi-dphy.c | 22 ++++++++++++++++++- > >  1 file changed, 21 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c b/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c > > index a95572b397ca..34e2d801e520 100644 > > --- a/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c > > +++ b/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c > > @@ -14,6 +14,7 @@ > >  #include > >  #include > >  #include > > +#include > >  #include > >   > >  /* DPHY registers */ > > @@ -93,6 +94,7 @@ struct mixel_dphy_cfg { > >  }; > >   > >  struct mixel_dphy_priv { > > + struct device *dev; > >   struct mixel_dphy_cfg cfg; > >   struct regmap *regmap; > >   struct clk *phy_ref_clk; > > @@ -382,6 +384,7 @@ static int mixel_dphy_power_on(struct phy *phy) > >   ret = clk_prepare_enable(priv->phy_ref_clk); > >   if (ret < 0) > >   return ret; > > + pm_runtime_get_sync(priv->dev); > >   > > This call can fail and will leave you with an elevated rpm refcount. > Better use the new pm_runtime_resume_and_get to avoid this issue? pm_runtime_resume_and_get is a nice API addition indeed. I added the error handling but opted to stay with `pm_runtime_get_sync` in this case since the error path already has a pm_runtime_put() hence avoiding another goto target. > > Nitpick: I would add a blank line before the call. Done. Thanks for having a look! -- Guido > > Regards, > Lucas >