From patchwork Mon May 2 09:38:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hector Martin X-Patchwork-Id: 12834062 X-Patchwork-Delegate: lorenzo.pieralisi@arm.com 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 94D70C4332F for ; Mon, 2 May 2022 09:39:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1384287AbiEBJmi (ORCPT ); Mon, 2 May 2022 05:42:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44806 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1384278AbiEBJm2 (ORCPT ); Mon, 2 May 2022 05:42:28 -0400 Received: from mail.marcansoft.com (marcansoft.com [IPv6:2a01:298:fe:f::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 45E9B1BE9E; Mon, 2 May 2022 02:38:59 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: hector@marcansoft.com) by mail.marcansoft.com (Postfix) with ESMTPSA id B4F7041E96; Mon, 2 May 2022 09:38:54 +0000 (UTC) From: Hector Martin To: Marc Zyngier Cc: Hector Martin , Lorenzo Pieralisi , Rob Herring , =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= , Bjorn Helgaas , Alyssa Rosenzweig , Sven Peter , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH 2/3] PCI: apple: Probe all GPIOs for availability first Date: Mon, 2 May 2022 18:38:31 +0900 Message-Id: <20220502093832.32778-3-marcan@marcan.st> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220502093832.32778-1-marcan@marcan.st> References: <20220502093832.32778-1-marcan@marcan.st> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org If we're probing the PCI controller and some GPIOs are not available and cause a probe defer, we can end up leaving some ports initialized and not others and making a mess. Check for PERST# GPIOs for all ports first, and just return -EPROBE_DEFER if any are not ready yet, without bringing anything up. Fixes: 1e33888fbe44 ("PCI: apple: Add initial hardware bring-up") Cc: stable@vger.kernel.org Signed-off-by: Hector Martin Acked-by: Marc Zyngier --- drivers/pci/controller/pcie-apple.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/drivers/pci/controller/pcie-apple.c b/drivers/pci/controller/pcie-apple.c index e0c06c0ee731..e3aa2d461739 100644 --- a/drivers/pci/controller/pcie-apple.c +++ b/drivers/pci/controller/pcie-apple.c @@ -507,6 +507,20 @@ static u32 apple_pcie_rid2sid_write(struct apple_pcie_port *port, return readl_relaxed(port->base + PORT_RID2SID(idx)); } +static int apple_pcie_probe_port(struct device_node *np) +{ + struct gpio_desc *gd; + + gd = gpiod_get_from_of_node(np, "reset-gpios", 0, + GPIOD_OUT_LOW, "PERST#"); + if (IS_ERR(gd)) { + return PTR_ERR(gd); + } + + gpiod_put(gd); + return 0; +} + static int apple_pcie_setup_port(struct apple_pcie *pcie, struct device_node *np) { @@ -797,8 +811,18 @@ static int apple_pcie_init(struct pci_config_window *cfg) static int apple_pcie_probe(struct platform_device *pdev) { + struct device *dev = &pdev->dev; + struct device_node *of_port; int ret; + /* Check for probe dependencies for all ports first */ + for_each_child_of_node(dev->of_node, of_port) { + ret = apple_pcie_probe_port(of_port); + of_node_put(of_port); + if (ret) + return dev_err_probe(dev, ret, "Port %pOF probe fail\n", of_port); + } + ret = bus_register_notifier(&pci_bus_type, &apple_pcie_nb); if (ret) return ret;