From patchwork Sun Sep 26 07:15:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhenneng Li X-Patchwork-Id: 12517975 X-Patchwork-Delegate: bhelgaas@google.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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F29D1C433F5 for ; Sun, 26 Sep 2021 07:15:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D0FD760EE0 for ; Sun, 26 Sep 2021 07:15:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231176AbhIZHR2 (ORCPT ); Sun, 26 Sep 2021 03:17:28 -0400 Received: from mailgw.kylinos.cn ([123.150.8.42]:58471 "EHLO nksmu.kylinos.cn" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S230035AbhIZHR2 (ORCPT ); Sun, 26 Sep 2021 03:17:28 -0400 X-UUID: 9b0812a5c71b4ad6bae7ac3a6100c2eb-20210926 X-CPASD-INFO: c744725bb5a6427f8a56ed2deac424f9@rIduVGRkY5KOVaOCg3WCoFiSZWaVkFK zp5uDZGBkklmVhH5xTWJsXVKBfG5QZWNdYVN_eGpQYl9gZFB5i3-XblBgXoZgUZB3snluVGdgZQ== X-CPASD-FEATURE: 0.0 X-CLOUD-ID: c744725bb5a6427f8a56ed2deac424f9 X-CPASD-SUMMARY: SIP:-1,APTIP:-2.0,KEY:0.0,FROMBLOCK:1,EXT:0.0,OB:0.0,URL:-5,T VAL:196.0,ESV:0.0,ECOM:-5.0,ML:0.0,FD:0.0,CUTS:174.0,IP:-2.0,MAL:0.0,ATTNUM:0 .0,PHF:-5.0,PHC:-5.0,SPF:4.0,EDMS:-3,IPLABEL:4480.0,FROMTO:0,AD:0,FFOB:0.0,CF OB:0.0,SPC:0.0,SIG:-5,AUF:3,DUF:14612,ACD:53,DCD:155,SL:0,AG:0,CFC:0.644,CFSR :0.029,UAT:0,RAF:0,VERSION:2.3.4 X-CPASD-ID: 9b0812a5c71b4ad6bae7ac3a6100c2eb-20210926 X-CPASD-BLOCK: 1000 X-CPASD-STAGE: 1, 1 X-UUID: 9b0812a5c71b4ad6bae7ac3a6100c2eb-20210926 X-User: lizhenneng@kylinos.cn Received: from localhost.localdomain [(116.128.244.169)] by nksmu.kylinos.cn (envelope-from ) (Generic MTA) with ESMTP id 1290208314; Sun, 26 Sep 2021 15:12:58 +0800 From: Zhenneng Li To: Bjorn Helgaas Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Zhenneng Li Subject: [PATCH] PCI/sysfs: add write attribute for boot_vga Date: Sun, 26 Sep 2021 15:15:39 +0800 Message-Id: <20210926071539.636644-1-lizhenneng@kylinos.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Add writing attribute for boot_vga sys node, so we can config default video display output dynamically when there are two video cards on a machine. Xorg server will determine running on which video card based on boot_vga node's value. Signed-off-by: Zhenneng Li --- drivers/pci/pci-sysfs.c | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index 7bbf2673c7f2..a6ba19ce7adb 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -664,7 +664,29 @@ static ssize_t boot_vga_show(struct device *dev, struct device_attribute *attr, !!(pdev->resource[PCI_ROM_RESOURCE].flags & IORESOURCE_ROM_SHADOW)); } -static DEVICE_ATTR_RO(boot_vga); + +static ssize_t boot_vga_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + unsigned long val; + struct pci_dev *pdev = to_pci_dev(dev); + struct pci_dev *vga_dev = vga_default_device(); + + if (kstrtoul(buf, 0, &val) < 0) + return -EINVAL; + + if (val != 1) + return -EINVAL; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (pdev != vga_dev) + vga_set_default_device(pdev); + + return count; +} +static DEVICE_ATTR_RW(boot_vga); static ssize_t pci_read_config(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buf,