From nobody Sun Feb 8 06:54:35 2026 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 AE6A6C001DB for ; Tue, 8 Aug 2023 22:34:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230407AbjHHWed (ORCPT ); Tue, 8 Aug 2023 18:34:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45128 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230233AbjHHWe3 (ORCPT ); Tue, 8 Aug 2023 18:34:29 -0400 Received: from out-127.mta1.migadu.com (out-127.mta1.migadu.com [IPv6:2001:41d0:203:375::7f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3BF9EFE for ; Tue, 8 Aug 2023 15:34:29 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1691534067; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=UkFV97CQa3g6DrhggAXuzog1hzg5W10mASK1ByxDhpo=; b=PHfyGfjJY9Ur7O6u9zSuqLtFOfBXyBXUUFDLn09wdIeOTXwBdqdeMkEVbAfYkp+pfrdwJh D5tcQm5d30zgqXzASPmeEsy3pgGMANJ4IzoPHXwSO2Y+GD73xe/yMnpf71ZJqNKtBbj1lo lXO2AMWaiQes21PRybH44bgkLzjtuk4= From: Sui Jingfeng To: Bjorn Helgaas Cc: Dave Airlie , Daniel Vetter , linux-pci@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Sui Jingfeng Subject: [PATCH v2 02/11] PCI: Add the pci_get_class_masked() helper Date: Wed, 9 Aug 2023 06:34:03 +0800 Message-Id: <20230808223412.1743176-3-sui.jingfeng@linux.dev> In-Reply-To: <20230808223412.1743176-1-sui.jingfeng@linux.dev> References: <20230808223412.1743176-1-sui.jingfeng@linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Sui Jingfeng Because there is no good way to get the mask member used to searching for devices that conform to a specific PCI class code, an application needs to process all PCI display devices can achieve its goal as follows: pdev =3D NULL; do { pdev =3D pci_get_class_masked(PCI_BASE_CLASS_DISPLAY << 16, 0xFF0000, pdev= ); if (pdev) do_something_for_pci_display_device(pdev); } while (pdev); While previously, we just can not ignore Sub-Class code and the Programming Interface byte when do the searching. Signed-off-by: Sui Jingfeng --- drivers/pci/search.c | 30 ++++++++++++++++++++++++++++++ include/linux/pci.h | 7 +++++++ 2 files changed, 37 insertions(+) diff --git a/drivers/pci/search.c b/drivers/pci/search.c index b4c138a6ec02..f1c15aea868b 100644 --- a/drivers/pci/search.c +++ b/drivers/pci/search.c @@ -334,6 +334,36 @@ struct pci_dev *pci_get_device(unsigned int vendor, un= signed int device, } EXPORT_SYMBOL(pci_get_device); =20 +/** + * pci_get_class_masked - begin or continue searching for a PCI device by = class and mask + * @class: search for a PCI device with this class designation + * @from: Previous PCI device found in search, or %NULL for new search. + * + * Iterates through the list of known PCI devices. If a PCI device is + * found with a matching @class, the reference count to the device is + * incremented and a pointer to its device structure is returned. + * Otherwise, %NULL is returned. + * A new search is initiated by passing %NULL as the @from argument. + * Otherwise if @from is not %NULL, searches continue from next device + * on the global list. The reference count for @from is always decremented + * if it is not %NULL. + */ +struct pci_dev *pci_get_class_masked(unsigned int class, unsigned int mask, + struct pci_dev *from) +{ + struct pci_device_id id =3D { + .vendor =3D PCI_ANY_ID, + .device =3D PCI_ANY_ID, + .subvendor =3D PCI_ANY_ID, + .subdevice =3D PCI_ANY_ID, + .class_mask =3D mask, + .class =3D class, + }; + + return pci_get_dev_by_id(&id, from); +} +EXPORT_SYMBOL(pci_get_class_masked); + /** * pci_get_class - begin or continue searching for a PCI device by class * @class: search for a PCI device with this class designation diff --git a/include/linux/pci.h b/include/linux/pci.h index 0ff7500772e6..b20e7ba844bf 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1180,6 +1180,9 @@ struct pci_dev *pci_get_slot(struct pci_bus *bus, uns= igned int devfn); struct pci_dev *pci_get_domain_bus_and_slot(int domain, unsigned int bus, unsigned int devfn); struct pci_dev *pci_get_class(unsigned int class, struct pci_dev *from); +struct pci_dev *pci_get_class_masked(unsigned int class, unsigned int mask, + struct pci_dev *from); + int pci_dev_present(const struct pci_device_id *ids); =20 int pci_bus_read_config_byte(struct pci_bus *bus, unsigned int devfn, @@ -1895,6 +1898,10 @@ static inline struct pci_dev *pci_get_class(unsigned= int class, struct pci_dev *from) { return NULL; } =20 +static inline struct pci_dev *pci_get_class_masked(unsigned int class, + unsigned int mask, + struct pci_dev *from) +{ return NULL; } =20 static inline int pci_dev_present(const struct pci_device_id *ids) { return 0; } --=20 2.34.1