From patchwork Fri Nov 6 19:42:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stuart Hayes X-Patchwork-Id: 1395912 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20161025 header.b=Mu3uJFl/; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4CSXYJ2cVQz9sPB for ; Sat, 7 Nov 2020 07:48:52 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728386AbgKFUsu (ORCPT ); Fri, 6 Nov 2020 15:48:50 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47294 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727559AbgKFUst (ORCPT ); Fri, 6 Nov 2020 15:48:49 -0500 Received: from mail-qt1-x836.google.com (mail-qt1-x836.google.com [IPv6:2607:f8b0:4864:20::836]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 90D6CC0613CF for ; Fri, 6 Nov 2020 12:48:49 -0800 (PST) Received: by mail-qt1-x836.google.com with SMTP id f93so1743662qtb.10 for ; Fri, 06 Nov 2020 12:48:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=7zkbvD+nRIG8Tarhi+gqM39jvhT0iQ+N4raXf+ViiYg=; b=Mu3uJFl/cGoZLwW2Wg6cWzw09/Ec2yvvv6q//AL29EWUgFlUExJC/AFHQtc3DEc6HM KHYHc3V/5Y8d1LDMvwqQqrVpgEO1h/93vShVG8udI5qh/uqpB2odEeD/iguP7qize6/T cRakDuUKzFzs/wmdNff7VDIuwR9D5jp7l6H8BMcIoozyMJ07pzzRUj9fd+68+WCK9MBo ikP2+377Y+nPZrPRq0TfjfAZTB7gmNE9bp/7unBDicJvybuO5FNGPKeTNzrgZpjme773 OmK/Bg9+SUimxPKgOfNbdRB7Ye0A5yrks4c4dYcJxO9dh3Xx6VnMZD3tdTZdn+vm9z85 xJWw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=7zkbvD+nRIG8Tarhi+gqM39jvhT0iQ+N4raXf+ViiYg=; b=ZEnMKeUU+JzJ+CwykGHgHnUeJmpBHmsHQjgekKI7Fi43qXcguBSge8ZxNJ1T1Ru493 6lm81qYeX3yM5FF4dPeJwNoe3TdxyXY0VPL5l8xr/JZad8mTQ4+vYkgLKhZE5T22Raa4 Oy9QUuhyXFUsWtE3efWNeY/4+v5OsKF2T1VS3/4r90t1I80HySxErHqMaPm4l9Lx/vds 0mR/p+P3DyYwv+uA5fbpMMJZz7PxcySch9MlOSJrr42U2cPZRnOyo9/LvQLtle6JYKuz 9AC16HB8JPZBSJB85i0IyQoT0C1OFDFwj86TSKIOEAG1UvXvCv946KLYXJ103CAJTKPj 8xaw== X-Gm-Message-State: AOAM5332IF2K2aMRO5MnkAoj5lCtJ33YBTMIyEeKjKxBTSmMxzWIJDRP RcqnlzmC5WKahTYKAsCIJiw= X-Google-Smtp-Source: ABdhPJxUhyZR6akNI7QgtVpMk+elHgBJTim67zen2nNdOOyjme9nFo0FU/KrQ48bAyAiYqyihfVc8g== X-Received: by 2002:aed:3031:: with SMTP id 46mr3388634qte.49.1604695728729; Fri, 06 Nov 2020 12:48:48 -0800 (PST) Received: from localhost.est.adc.delllabs.net ([143.166.81.254]) by smtp.googlemail.com with ESMTPSA id m27sm1388126qtm.72.2020.11.06.12.48.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 06 Nov 2020 12:48:48 -0800 (PST) From: Stuart Hayes To: Bjorn Helgaas Cc: linux-pci@vger.kernel.org, Stuart Hayes Subject: [PATCH] Expose PCIe SSD Status LED Management DSM in sysfs Date: Fri, 6 Nov 2020 13:42:21 -0600 Message-Id: <20201106194221.59353-1-stuart.w.hayes@gmail.com> X-Mailer: git-send-email 2.18.1 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org This patch will expose the PCIe SSD Status LED Management interface in sysfs for devices that have the relevant _DSM method, per the "_DSM additions for PCIe SSD Status LED Management" ECN to the PCI Firmware Specification revision 3.2. The interface is exposed in two sysfs files, ssdleds_supported_states (RO) and ssdleds_current_state (RW). Signed-off-by: Stuart Hayes Reported-by: kernel test robot Reported-by: kernel test robot --- Documentation/ABI/testing/sysfs-bus-pci | 14 ++ drivers/pci/Kconfig | 7 + drivers/pci/Makefile | 1 + drivers/pci/pci-ssdleds.c | 194 ++++++++++++++++++++++++ drivers/pci/pci-sysfs.c | 1 + drivers/pci/pci.h | 11 ++ 6 files changed, 228 insertions(+) create mode 100644 drivers/pci/pci-ssdleds.c diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index 450296cc7948..bee7855e408a 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -360,3 +360,17 @@ Contact: Heiner Kallweit Description: If ASPM is supported for an endpoint, these files can be used to disable or enable the individual power management states. Write y/1/on to enable, n/0/off to disable. + +What: /sys/bus/pci/devices/.../ssdleds_supported_states +Date: October 2020 +Contact: Stuart Hayes +Description: If the device supports the ACPI _DSM method to control the + PCIe SSD LED states, ssdleds_supported_states (read only) + will show the LED states that are supported by the _DSM. + +What: /sys/bus/pci/devices/.../ssdleds_current_state +Date: October 2020 +Contact: Stuart Hayes +Description: If the device supports the ACPI _DSM method to control the + PCIe SSD LED states, ssdleds_current_state will show or set + the current LED states that are active. diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig index 0c473d75e625..a56b94764182 100644 --- a/drivers/pci/Kconfig +++ b/drivers/pci/Kconfig @@ -182,6 +182,13 @@ config PCI_LABEL def_bool y if (DMI || ACPI) select NLS +config PCI_SSDLEDS + def_bool y if (ACPI) + depends on ACPI + help + Enables userspace access to PCIe SSD LED management interface via + sysfs. + config PCI_HYPERV tristate "Hyper-V PCI Frontend" depends on X86_64 && HYPERV && PCI_MSI && PCI_MSI_IRQ_DOMAIN && SYSFS diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile index 522d2b974e91..75d3d5a3b1ed 100644 --- a/drivers/pci/Makefile +++ b/drivers/pci/Makefile @@ -23,6 +23,7 @@ obj-$(CONFIG_PCI_ATS) += ats.o obj-$(CONFIG_PCI_IOV) += iov.o obj-$(CONFIG_PCI_BRIDGE_EMUL) += pci-bridge-emul.o obj-$(CONFIG_PCI_LABEL) += pci-label.o +obj-$(CONFIG_PCI_SSDLEDS) += pci-ssdleds.o obj-$(CONFIG_X86_INTEL_MID) += pci-mid.o obj-$(CONFIG_PCI_SYSCALL) += syscall.o obj-$(CONFIG_PCI_STUB) += pci-stub.o diff --git a/drivers/pci/pci-ssdleds.c b/drivers/pci/pci-ssdleds.c new file mode 100644 index 000000000000..7b9afd3d0ccb --- /dev/null +++ b/drivers/pci/pci-ssdleds.c @@ -0,0 +1,194 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Provide userspace access to PCIe SSD Status LED Management + * + * The PCIe spec defines an ACPI _DSM method to allow PCIe SSD status LED + * management (see "_DSM additions for PCIe SSD Status LED Management" ECN, + * February 12, 2020). This code provides a sysfs interface to this _DSM. + * + * Copyright (C) 2020 Dell Inc. + * + */ + +#include +#include +#include +#include + +const guid_t pci_ssdleds_dsm_guid = + GUID_INIT(0x5d524d9d, 0xfff9, 0x4d4b, + 0x8c, 0xb7, 0x74, 0x7e, 0xd5, 0x1e, 0x19, 0x4d); + +#define SSDLEDS_GET_SUPPORTED_STATES_DSM 0x01 +#define SSDLEDS_GET_STATE_DSM 0x02 +#define SSDLEDS_SET_STATE_DSM 0x03 + +struct pci_ssdleds_dsm_output { + u16 status; + u8 function_specific_err; + u8 vendor_specific_err; + u32 state; +}; + +static int ssdleds_dsm_set(struct device *dev, const char *buf, u64 dsm_func) +{ + acpi_handle handle; + union acpi_object *out_obj, arg3[2]; + struct pci_ssdleds_dsm_output *dsm_output; + u32 val; + int err; + + handle = ACPI_HANDLE(dev); + if (!handle) + return -ENODEV; + + err = kstrtou32(buf, 0, &val); + if (err || val > U32_MAX) + return -EINVAL; + + arg3[0].type = ACPI_TYPE_PACKAGE; + arg3[0].package.count = 1; + arg3[0].package.elements = &arg3[1]; + + arg3[1].type = ACPI_TYPE_BUFFER; + arg3[1].buffer.length = 4; + arg3[1].buffer.pointer = (u8 *)&val; + + out_obj = acpi_evaluate_dsm_typed(handle, &pci_ssdleds_dsm_guid, 0x1, + dsm_func, &arg3[0], ACPI_TYPE_BUFFER); + if (!out_obj) + return -EIO; + + if (out_obj->buffer.length < 8) { + ACPI_FREE(out_obj); + return -EIO; + } + + dsm_output = (struct pci_ssdleds_dsm_output *)out_obj->buffer.pointer; + /* + * Ignore function specific error bit 1 (some LED state bits weren't + * set), since write was done. User can read current state to see which + * bits were set. + */ + if (dsm_output->status != 0 && + !(dsm_output->status == 4 && dsm_output->function_specific_err == 1)) { + ACPI_FREE(out_obj); + return -EIO; + } + + ACPI_FREE(out_obj); + + return 0; +} + +static int ssdleds_dsm_get(struct device *dev, char *buf, u64 dsm_func) +{ + acpi_handle handle; + union acpi_object *out_obj; + struct pci_ssdleds_dsm_output *dsm_output; + + handle = ACPI_HANDLE(dev); + if (!handle) + return -ENODEV; + + out_obj = acpi_evaluate_dsm_typed(handle, &pci_ssdleds_dsm_guid, 0x1, + dsm_func, NULL, ACPI_TYPE_BUFFER); + if (!out_obj) + return -EIO; + + if (out_obj->buffer.length < 8) { + ACPI_FREE(out_obj); + return -EIO; + } + + dsm_output = (struct pci_ssdleds_dsm_output *)out_obj->buffer.pointer; + if (dsm_output->status != 0) { + ACPI_FREE(out_obj); + return -EIO; + } + + scnprintf(buf, PAGE_SIZE, "%#x\n", dsm_output->state); + + ACPI_FREE(out_obj); + + return strlen(buf) > 0 ? strlen(buf) : -EIO; +} + +static bool device_has_dsm(struct device *dev) +{ + acpi_handle handle; + + handle = ACPI_HANDLE(dev); + if (!handle) + return false; + + return !!acpi_check_dsm(handle, &pci_ssdleds_dsm_guid, 0x1, + 1 << SSDLEDS_GET_SUPPORTED_STATES_DSM || + 1 << SSDLEDS_GET_STATE_DSM || + 1 << SSDLEDS_SET_STATE_DSM); +} + +static ssize_t ssdleds_current_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int ret; + + ret = ssdleds_dsm_set(dev, buf, SSDLEDS_SET_STATE_DSM); + return (ret < 0) ? ret : count; +} + +static ssize_t ssdleds_current_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return ssdleds_dsm_get(dev, buf, SSDLEDS_GET_STATE_DSM); +} + +static ssize_t ssdleds_supported_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return ssdleds_dsm_get(dev, buf, SSDLEDS_GET_SUPPORTED_STATES_DSM); +} + +static umode_t ssdleds_attr_visible(struct kobject *kobj, + struct attribute *attr, int n) +{ + struct device *dev = kobj_to_dev(kobj); + umode_t mode = attr->mode; + + return device_has_dsm(dev) ? mode : 0; +} + +static struct device_attribute ssdleds_attr_current = { + .attr = {.name = "ssdleds_current_state", .mode = 0644}, + .show = ssdleds_current_show, + .store = ssdleds_current_store, +}; + +static struct device_attribute ssdleds_attr_supported = { + .attr = {.name = "ssdleds_supported_states", .mode = 0444}, + .show = ssdleds_supported_show, +}; + +static struct attribute *ssdleds_attributes[] = { + &ssdleds_attr_current.attr, + &ssdleds_attr_supported.attr, + NULL, +}; + +static const struct attribute_group ssdleds_attr_group = { + .attrs = ssdleds_attributes, + .is_visible = ssdleds_attr_visible, +}; + +void pci_create_ssdleds_files(struct pci_dev *pdev) +{ + int ret; + + ret = sysfs_create_group(&pdev->dev.kobj, &ssdleds_attr_group); +} + +void pci_remove_ssdleds_files(struct pci_dev *pdev) +{ + sysfs_remove_group(&pdev->dev.kobj, &ssdleds_attr_group); +} diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index d15c881e2e7e..820f32956971 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -1377,6 +1377,7 @@ int __must_check pci_create_sysfs_dev_files(struct pci_dev *pdev) goto err_rom_file; pci_create_firmware_label_files(pdev); + pci_create_ssdleds_files(pdev); return 0; diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index f86cae9aa1f4..8e6883a1b701 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -30,6 +30,17 @@ static inline void pci_remove_firmware_label_files(struct pci_dev *pdev) void pci_create_firmware_label_files(struct pci_dev *pdev); void pci_remove_firmware_label_files(struct pci_dev *pdev); #endif + +#if !defined(CONFIG_PCI_SSDLEDS) +static inline void pci_create_ssdleds_files(struct pci_dev *pdev) +{ return; } +static inline void pci_remove_ssdleds_files(struct pci_dev *pdev) +{ return; } +#else +void pci_create_ssdleds_files(struct pci_dev *pdev); +void pci_remove_ssdleds_files(struct pci_dev *pdev); +#endif + void pci_cleanup_rom(struct pci_dev *dev); enum pci_mmap_api {