From patchwork Tue Nov 10 15:37:35 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: stuart hayes X-Patchwork-Id: 11894831 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 452E7697 for ; Tue, 10 Nov 2020 16:44:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1AAAA207D3 for ; Tue, 10 Nov 2020 16:44:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="YWD4UYI4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726706AbgKJQoZ (ORCPT ); Tue, 10 Nov 2020 11:44:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53628 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726152AbgKJQoY (ORCPT ); Tue, 10 Nov 2020 11:44:24 -0500 Received: from mail-qk1-x72c.google.com (mail-qk1-x72c.google.com [IPv6:2607:f8b0:4864:20::72c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7F3B9C0613CF for ; Tue, 10 Nov 2020 08:44:23 -0800 (PST) Received: by mail-qk1-x72c.google.com with SMTP id v143so7517482qkb.2 for ; Tue, 10 Nov 2020 08:44:23 -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=xf26olugM7i4GwxdO8nDUCglJTZeWhEQOwUVRID66YQ=; b=YWD4UYI4e57IzMyimJifOZxcn/u1xrETVn+aHKOJ3QStnZWzrRyklXLGQ4Csg9uz/4 JNNh3KLfveYOOOUeTiB5sygLaPZyAchRa8v9pu+UG6CfcwmpuMrQXw3PX3IWgsl9jHP8 1gUzuhFB/zohLrx148RZ78EK8fLlH4IvgfN0ypQ1znV//xUXjGaSeVfC4wqZU2n4bNXU cHD81JKDXqY5pwpdpxAcwmNSkymGKxhRu/4pXewKTLQqCqfSH8EN0ZfX245QG9TXt5sn yYjVb070kXfBjoZ+9i+BIKzf1ftLw6SFOIBEubP18+XAVINaKHC+zxe8spY0k4mGcBml iThA== 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=xf26olugM7i4GwxdO8nDUCglJTZeWhEQOwUVRID66YQ=; b=V5um/1jXgm/BQl1eTwN5qbZ0kySskI0uKvinoMd+COlDxFxmHpi7fyzk2vxhb28M1J nr9+ahvqNRaQggUHiCqWTrkfgdXXBx9xKGNZMgyoqqdKx/HVZexfhgEYEEbwxR5HTduE qkgfilP6b1j58kbZAvrvF0VrhoodD+kSbU6joSla2oHoYKKuCpnlawGoDmgmf1n9H9bh Q2dkWvqzG7UOV0Rbsfi6DIxYtHZ4/F7JvZZpMRwCSm4Wk8jTAWMaKIfr/BWN3XTrBEM9 SWdaJGiXiThG4k1fB8bqsz+vL8zCVMHWmcFkRRnLsqgsxsD7E4OrabRROjETjHakqFyM BMdA== X-Gm-Message-State: AOAM532fh95WwsNv7qvR5y5TrQRxr0N4RNejA2qUO6YEUnG1KGxs7q86 D0LeYgD96i7jQc43rPyF9Do= X-Google-Smtp-Source: ABdhPJwtofOmA0v2SrxAodePpdE+CUbuNm8awT3pHZRlzjqqF7U4+a833JlK+SzMZPI9GoJut3v0kg== X-Received: by 2002:a37:2716:: with SMTP id n22mr2132250qkn.500.1605026662643; Tue, 10 Nov 2020 08:44:22 -0800 (PST) Received: from localhost.est.adc.delllabs.net ([143.166.81.254]) by smtp.googlemail.com with ESMTPSA id p72sm5242572qke.110.2020.11.10.08.44.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 10 Nov 2020 08:44:21 -0800 (PST) From: Stuart Hayes To: Bjorn Helgaas Cc: linux-pci@vger.kernel.org, Stuart Hayes Subject: [PATCH v2] Expose PCIe SSD Status LED Management DSM in sysfs Date: Tue, 10 Nov 2020 09:37:35 -0600 Message-Id: <20201110153735.58587-1-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: Dan Carpenter --- v2: made PCI_SSDLEDS dependent on PCI and ACPI remove unused variable warn if call to sysfs_create_group fails include header file with function prototypes change logical OR to bitwise --- 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 77ad9ec3c801..18ca73b764ac 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -366,3 +366,17 @@ 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..48049866145f 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 && PCI) + depends on PCI && 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..d35e4f3caa71 --- /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 +#include "pci.h" + +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) +{ + if (sysfs_create_group(&pdev->dev.kobj, &ssdleds_attr_group)) + pci_warn(pdev, "Unable to create ssdleds attributes\n"); +} + +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 {