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 16F38C433EF for ; Mon, 25 Apr 2022 09:21:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234799AbiDYJYV convert rfc822-to-8bit (ORCPT ); Mon, 25 Apr 2022 05:24:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34322 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234599AbiDYJYQ (ORCPT ); Mon, 25 Apr 2022 05:24:16 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DF75B2668 for ; Mon, 25 Apr 2022 02:21:12 -0700 (PDT) Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1niutp-0003uW-GT; Mon, 25 Apr 2022 11:20:53 +0200 Received: from [2a0a:edc0:0:900:1d::4e] (helo=lupine) by drehscheibe.grey.stw.pengutronix.de with esmtp (Exim 4.94.2) (envelope-from ) id 1niuto-0057Sx-PG; Mon, 25 Apr 2022 11:20:51 +0200 Received: from pza by lupine with local (Exim 4.94.2) (envelope-from ) id 1niutm-0004WV-OB; Mon, 25 Apr 2022 11:20:50 +0200 Message-ID: <25fbf4763c28af4c73162dec254af6111e05461b.camel@pengutronix.de> Subject: Re: [PATCH v8 2/5] PCI: dwc: rockchip: reset core at driver probe From: Philipp Zabel To: Peter Geis , Lorenzo Pieralisi , Rob Herring , Krzysztof =?UTF-8?Q?Wilczy=C5=84ski?= , Bjorn Helgaas , Heiko Stuebner Cc: linux-rockchip@lists.infradead.org, Marc Zyngier , linux-pci@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Date: Mon, 25 Apr 2022 11:20:50 +0200 In-Reply-To: <20220423152403.1681222-3-pgwipeout@gmail.com> References: <20220423152403.1681222-1-pgwipeout@gmail.com> <20220423152403.1681222-3-pgwipeout@gmail.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT User-Agent: Evolution 3.38.3-1 MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: p.zabel@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-pci@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Hi Peter, On Sa, 2022-04-23 at 11:24 -0400, Peter Geis wrote: > The PCIe controller is in an unknown state at driver probe. This can > lead to undesireable effects when the driver attempts to configure the > controller. > > Prevent issues in the future by resetting the core during probe. > > Signed-off-by: Peter Geis > --- >  drivers/pci/controller/dwc/pcie-dw-rockchip.c | 22 +++++++------------ >  1 file changed, 8 insertions(+), 14 deletions(-) > > diff --git a/drivers/pci/controller/dwc/pcie-dw-rockchip.c b/drivers/pci/controller/dwc/pcie-dw-rockchip.c > index c9b341e55cbb..d67ed811e752 100644 > --- a/drivers/pci/controller/dwc/pcie-dw-rockchip.c > +++ b/drivers/pci/controller/dwc/pcie-dw-rockchip.c > @@ -152,7 +152,13 @@ static int rockchip_pcie_resource_get(struct platform_device *pdev, >   if (IS_ERR(rockchip->rst_gpio)) >   return PTR_ERR(rockchip->rst_gpio); > > - return 0; > + rockchip->rst = devm_reset_control_array_get_exclusive(&pdev->dev); > + if (IS_ERR(rockchip->rst)) > + return dev_err_probe(&pdev->dev, PTR_ERR(rockchip->rst), > + "failed to get reset lines\n"); > + > + return reset_control_assert(rockchip->rst); This makes "rockchip_pcie_resource_get" a bit of a misnomer, maybe move this out into rockchip_pcie_probe()? > + Superfluous whitespace. regards Philipp