From patchwork Thu Dec 19 12:38:14 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiang Liu X-Patchwork-Id: 303530 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 486722C0089 for ; Thu, 19 Dec 2013 23:46:34 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755522Ab3LSMnX (ORCPT ); Thu, 19 Dec 2013 07:43:23 -0500 Received: from mga09.intel.com ([134.134.136.24]:17205 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753246Ab3LSMnW (ORCPT ); Thu, 19 Dec 2013 07:43:22 -0500 Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga102.jf.intel.com with ESMTP; 19 Dec 2013 04:39:32 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.95,512,1384329600"; d="scan'208";a="427187739" Received: from gerry-dev.bj.intel.com ([10.238.158.74]) by orsmga001.jf.intel.com with ESMTP; 19 Dec 2013 04:43:17 -0800 From: Jiang Liu To: "Rafael J . Wysocki" , Bjorn Helgaas , Lv Zheng , Len Brown Cc: Jiang Liu , Tony Luck , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org Subject: [Patch v2 05/13] PCI, pci-label: treat PCI label with index 0 as valid label Date: Thu, 19 Dec 2013 20:38:14 +0800 Message-Id: <1387456702-4709-6-git-send-email-jiang.liu@linux.intel.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1387456702-4709-1-git-send-email-jiang.liu@linux.intel.com> References: <1387456702-4709-1-git-send-email-jiang.liu@linux.intel.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Current pci-label driver detects ACPI label by checking label index returned by ACPI _DSM method, and treat it as valid if label index is positive. According to ACPI Firmware specification 3.1, zero is also an valid label index. So change code to detect availability of ACPI slot label by checking availaiblity of ACPI _DSM function for PCI label. Signed-off-by: Jiang Liu --- drivers/pci/pci-label.c | 34 ++++++++++++++++++---------------- 1 file changed, 18 insertions(+), 16 deletions(-) diff --git a/drivers/pci/pci-label.c b/drivers/pci/pci-label.c index f12dcd1..0260b14 100644 --- a/drivers/pci/pci-label.c +++ b/drivers/pci/pci-label.c @@ -187,7 +187,6 @@ static const char device_label_dsm_uuid[] = { }; enum acpi_attr_enum { - ACPI_ATTR_NONE = 0, ACPI_ATTR_LABEL_SHOW, ACPI_ATTR_INDEX_SHOW, }; @@ -222,20 +221,16 @@ dsm_get_label(struct device *dev, char *buf, enum acpi_attr_enum attr) if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 2 && tmp[0].type == ACPI_TYPE_INTEGER && tmp[1].type == ACPI_TYPE_STRING) { - len = tmp[0].integer.value; - if (buf) { - /* - * This second string element is optional even when - * this _DSM is implemented; when not implemented, - * this entry must return a null string. - */ - if (attr == ACPI_ATTR_INDEX_SHOW) - scnprintf(buf, PAGE_SIZE, "%llu\n", - tmp->integer.value); - else if (attr == ACPI_ATTR_LABEL_SHOW) - dsm_label_utf16s_to_utf8s(tmp + 1, buf); - len = strlen(buf) > 0 ? strlen(buf) : -1; - } + /* + * The second string element is optional even when + * this _DSM is implemented; when not implemented, + * this entry must return a null string. + */ + if (attr == ACPI_ATTR_INDEX_SHOW) + scnprintf(buf, PAGE_SIZE, "%llu\n", tmp->integer.value); + else if (attr == ACPI_ATTR_LABEL_SHOW) + dsm_label_utf16s_to_utf8s(tmp + 1, buf); + len = strlen(buf) > 0 ? strlen(buf) : -1; } ACPI_FREE(obj); @@ -246,7 +241,14 @@ dsm_get_label(struct device *dev, char *buf, enum acpi_attr_enum attr) static bool device_has_dsm(struct device *dev) { - return dsm_get_label(dev, NULL, ACPI_ATTR_NONE) > 0; + acpi_handle handle; + + handle = ACPI_HANDLE(dev); + if (!handle) + return false; + + return !!acpi_check_dsm(handle, device_label_dsm_uuid, 0x2, + 1 << DEVICE_LABEL_DSM); } static umode_t