From nobody Tue Feb 10 11:56:24 2026 Received: from mail-dy1-f170.google.com (mail-dy1-f170.google.com [74.125.82.170]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E6D0314B950 for ; Tue, 10 Feb 2026 01:17:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.170 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770686228; cv=none; b=aUypjBbmRZmBDkUUYWeuXU5kTriN72AOjXl3kZAynjPLKQlHlIMZj3yCwBqv+xXxRDkQgPAIUH+ztr2WEmqrfxMg2AylRfkFoMQ5hNj6K3gMbyT6TBVsZDaLsoh4UVzfUVY2ft3LwfDrRXdRRZ4Kqih0WOezX3AZ8AxCBoPTJY4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770686228; c=relaxed/simple; bh=3rQT1ZXwHV/aNuRkhTms30L7bcfKATRXNqULQYhc0+Q=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=haWRQwyYlDqy5FVzp5hozGDaRIJGfx03dUAs5GSbXQjqhCWX+6z3dZCX79oVIzAmTJLyG4F7447cVkrv/96lcWhqwuZ3XUXVPAsU75/eDyIn+EHE+whw81qipLDwEiHU8X7kVm3vCCdsB8Mr4/umWr3Ql/UmvoozPz7UCPF37X4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org; spf=pass smtp.mailfrom=chromium.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b=LeUXQE5+; arc=none smtp.client-ip=74.125.82.170 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chromium.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="LeUXQE5+" Received: by mail-dy1-f170.google.com with SMTP id 5a478bee46e88-2b86d3c909dso1784507eec.1 for ; Mon, 09 Feb 2026 17:17:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1770686226; x=1771291026; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=sPkH+QdMmWbvs590N9FGAiv6noldst9vpcbNY7dgv2o=; b=LeUXQE5+cImPQyUiw4Sc3lTX3y2cip1dfLY9t602DHFx+WHvCzLwotlfnR0ILEZhb3 bsYuG2MI2pzYQVN+wuMfqYLLJzWoU4bFK+DJMP57pL2AWXMmSJ2Qwi8snzbN6M9haSje L5T8CNQb3hCter6jJD2lM35RPAsFJk1nQA+js= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1770686226; x=1771291026; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=sPkH+QdMmWbvs590N9FGAiv6noldst9vpcbNY7dgv2o=; b=iAJTipfUR7gCitZME/m+jJh67K0rNtaNfk76yVd0JMHXc0LBSx34s/Mhz7Voctp8KI JnvLh03jb9VuTJrzqxAPGrtZWA7Ej9nip8lJusH2rmC1bwZGz+8xARa1cweVbpTiGruI n3ZuHIKDzliUxVmAAgNwDmhM4a/FSg6o1Y0uVt574VxzkCdPQCZWqnhk7hl33hZIBjUH xYxkWc/KEzjvVMx6zbBEzMa3vGbSwO/MkVzaV6wfKKGA/nhBoPzvNyvnjXfY1bFyQtkN FRlbuvL6o8zmVnFX8i986fbVLw/Zt2HJILtNsoqbopSyLaeMUOcrf0w/9RY50nwMXnp3 cobA== X-Gm-Message-State: AOJu0Yy6Ze8n1VI5ek5foUNLe7rcJXA+KbsQI5C4yzR5VCSrqQ/HnTfM Psdra6lpxgCKJI0AYzT/fk2LKdJXF3PAkIfaHhUzi3BoM8OqQBEedd5ZO91xzwrCVUCazpQjp/F 8Tv4= X-Gm-Gg: AZuq6aKuVq91XMOREVJHiv5rmp+4lniLY7gnZV9zRXKK3VQkV/yBINHkHJrKsX047wi 7zSrn5uiC+Ud7herB/U+ONujOkGJ5wujY7dg45jvUGhsDb6kJ1hH6T3UvZepT5MXkbHHK6wBdxo Vh1XcQxfg5Rw1rPBftrR19wXrB4MIu3gtRl8w6MhZ0NYorCS9Goh0A/6VQf/aAEdFz/X34lihg2 E2l/qFgQdksaVaA8xbgVNi3UG6+dttQgqX+5Zc6NrMut6BLSsTAXXvusKFO7Yu7MFlgQq9j5nRJ EeOouZof4vmziOUBCPB/ew+gNKbx9eoGql/iLxnsI9mEH3YREdyQbEeXjsY/mcRt/DDJ3KTPEDR ZpPeoOIpytKUGljUv4mXeafZg+XvUA+xNSfsF2InIj4u8rM4XITEhW7TJD6OLZVb4tGEYO8jCtu kEBFtyFAMd4EzsvE75SaTPJN9dG5f/CjamPTwOKkpPbJpySJNaqTl9oTBrJw6i7w== X-Received: by 2002:a05:7300:c9e:b0:2b7:857:db6a with SMTP id 5a478bee46e88-2b85672be26mr6509418eec.21.1770686225789; Mon, 09 Feb 2026 17:17:05 -0800 (PST) Received: from localhost ([2a00:79e0:2e7c:8:b8b8:83d8:d937:b0f8]) by smtp.gmail.com with UTF8SMTPSA id 5a478bee46e88-2b855c8d90bsm8479736eec.33.2026.02.09.17.17.04 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 09 Feb 2026 17:17:05 -0800 (PST) From: Brian Norris To: Bjorn Helgaas Cc: linux-kernel@vger.kernel.org, Lukas Wunner , Manivannan Sadhasivam , linux-pci@vger.kernel.org, Brian Norris Subject: [PATCH v2] PCI/portdrv: Allow probing even without child services Date: Mon, 9 Feb 2026 17:15:35 -0800 Message-ID: <20260209171535.v2.1.I5fd5d83f518681b3949d8ab2f16ba8244fd3e774@changeid> X-Mailer: git-send-email 2.53.0.239.g8d8fc8a987-goog Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The PCIe port driver fails to probe if it finds no child services, presumably under the assumption that the driver is not useful in that case. However, the driver *can* still be useful for power management support -- namely, it still configures the port for runtime PM / D3, which may be important for allowing a bridge to enter low power modes. Thus, allow probe to succeed even if no IRQs and no child services are available. This also mirrors existing behavior for ports that have no PCIe capabilities, where we'd also probe successfully. This change is a bit more important after commit f5cd8a929c82 ("PCI: dwc: Remove MSI/MSIX capability for Root Port if iMSI-RX is used as MSI controller"), because it's common for some DWC-based systems to: 1. have only have the "aer" and "pcie_pme" port services available and 2. not define legacy INTx interrupts properly in their device tree. After commit f5cd8a929c82, such systems may fail pcie_init_service_irqs() and so exit with -ENODEV. Link: https://lore.kernel.org/all/nyada24tqwlkzdceyoxbzitzygvp4elvj5oajnqdw= b33xkcdwk@76vnrx45fsfd/ Signed-off-by: Brian Norris --- Changes in v2: * clear master when we have no child services drivers/pci/pcie/portdrv.c | 21 +++++++-------------- 1 file changed, 7 insertions(+), 14 deletions(-) diff --git a/drivers/pci/pcie/portdrv.c b/drivers/pci/pcie/portdrv.c index 88af0dacf351..19b08f3653ee 100644 --- a/drivers/pci/pcie/portdrv.c +++ b/drivers/pci/pcie/portdrv.c @@ -330,7 +330,7 @@ static int pcie_device_init(struct pci_dev *pdev, int s= ervice, int irq) */ static int pcie_port_device_register(struct pci_dev *dev) { - int status, capabilities, i, nr_service; + int status, capabilities, i; int irqs[PCIE_PORT_DEVICE_MAXSERVICES]; =20 /* Enable PCI Express port device */ @@ -355,29 +355,22 @@ static int pcie_port_device_register(struct pci_dev *= dev) if (status) { capabilities &=3D PCIE_PORT_SERVICE_HP; if (!capabilities) - goto error_disable; + goto out; } =20 /* Allocate child services if any */ - status =3D -ENODEV; - nr_service =3D 0; for (i =3D 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++) { int service =3D 1 << i; if (!(capabilities & service)) continue; - if (!pcie_device_init(dev, service, irqs[i])) - nr_service++; + pcie_device_init(dev, service, irqs[i]); } - if (!nr_service) - goto error_cleanup_irqs; =20 +out: + /* With no child services, we shouldn't need bus mastering. */ + if (!capabilities) + pci_clear_master(dev); return 0; - -error_cleanup_irqs: - pci_free_irq_vectors(dev); -error_disable: - pci_disable_device(dev); - return status; } =20 typedef int (*pcie_callback_t)(struct pcie_device *); --=20 2.53.0.239.g8d8fc8a987-goog