diff options
Diffstat (limited to 'drivers/pci/pci-label.c')
| -rw-r--r-- | drivers/pci/pci-label.c | 206 |
1 files changed, 185 insertions, 21 deletions
diff --git a/drivers/pci/pci-label.c b/drivers/pci/pci-label.c index 90c0a729cd3..a3fbe2012ea 100644 --- a/drivers/pci/pci-label.c +++ b/drivers/pci/pci-label.c @@ -5,6 +5,13 @@ * by Narendra K <Narendra_K@dell.com>, * Jordan Hargrave <Jordan_Hargrave@dell.com> * + * PCI Firmware Specification Revision 3.1 section 4.6.7 (DSM for Naming a + * PCI or PCI Express Device Under Operating Systems) defines an instance + * number and string name. This code retrieves them and exports them to sysfs. + * If the system firmware does not provide the ACPI _DSM (Device Specific + * Method), then the SMBIOS type 41 instance number and string is exported to + * sysfs. + * * SMBIOS defines type 41 for onboard pci devices. This code retrieves * the instance number and string from the type 41 record and exports * it to sysfs. @@ -19,17 +26,22 @@ #include <linux/pci_ids.h> #include <linux/module.h> #include <linux/device.h> +#include <linux/nls.h> +#include <linux/acpi.h> +#include <linux/pci-acpi.h> #include "pci.h" +#define DEVICE_LABEL_DSM 0x07 + +#ifdef CONFIG_DMI enum smbios_attr_enum { SMBIOS_ATTR_NONE = 0, SMBIOS_ATTR_LABEL_SHOW, SMBIOS_ATTR_INSTANCE_SHOW, }; -static mode_t -find_smbios_instance_string(struct pci_dev *pdev, char *buf, - enum smbios_attr_enum attribute) +static size_t find_smbios_instance_string(struct pci_dev *pdev, char *buf, + enum smbios_attr_enum attribute) { const struct dmi_device *dmi; struct dmi_dev_onboard *donboard; @@ -61,9 +73,8 @@ find_smbios_instance_string(struct pci_dev *pdev, char *buf, return 0; } -static mode_t -smbios_instance_string_exist(struct kobject *kobj, struct attribute *attr, - int n) +static umode_t smbios_instance_string_exist(struct kobject *kobj, + struct attribute *attr, int n) { struct device *dev; struct pci_dev *pdev; @@ -75,8 +86,8 @@ smbios_instance_string_exist(struct kobject *kobj, struct attribute *attr, S_IRUGO : 0; } -static ssize_t -smbioslabel_show(struct device *dev, struct device_attribute *attr, char *buf) +static ssize_t smbioslabel_show(struct device *dev, + struct device_attribute *attr, char *buf) { struct pci_dev *pdev; pdev = to_pci_dev(dev); @@ -85,9 +96,8 @@ smbioslabel_show(struct device *dev, struct device_attribute *attr, char *buf) SMBIOS_ATTR_LABEL_SHOW); } -static ssize_t -smbiosinstance_show(struct device *dev, - struct device_attribute *attr, char *buf) +static ssize_t smbiosinstance_show(struct device *dev, + struct device_attribute *attr, char *buf) { struct pci_dev *pdev; pdev = to_pci_dev(dev); @@ -117,27 +127,181 @@ static struct attribute_group smbios_attr_group = { .is_visible = smbios_instance_string_exist, }; -static int -pci_create_smbiosname_file(struct pci_dev *pdev) +static int pci_create_smbiosname_file(struct pci_dev *pdev) { - if (!sysfs_create_group(&pdev->dev.kobj, &smbios_attr_group)) - return 0; - return -ENODEV; + return sysfs_create_group(&pdev->dev.kobj, &smbios_attr_group); } -static void -pci_remove_smbiosname_file(struct pci_dev *pdev) +static void pci_remove_smbiosname_file(struct pci_dev *pdev) { sysfs_remove_group(&pdev->dev.kobj, &smbios_attr_group); } +#else +static inline int pci_create_smbiosname_file(struct pci_dev *pdev) +{ + return -1; +} + +static inline void pci_remove_smbiosname_file(struct pci_dev *pdev) +{ +} +#endif + +#ifdef CONFIG_ACPI +static const char device_label_dsm_uuid[] = { + 0xD0, 0x37, 0xC9, 0xE5, 0x53, 0x35, 0x7A, 0x4D, + 0x91, 0x17, 0xEA, 0x4D, 0x19, 0xC3, 0x43, 0x4D +}; + +enum acpi_attr_enum { + ACPI_ATTR_LABEL_SHOW, + ACPI_ATTR_INDEX_SHOW, +}; + +static void dsm_label_utf16s_to_utf8s(union acpi_object *obj, char *buf) +{ + int len; + len = utf16s_to_utf8s((const wchar_t *)obj->string.pointer, + obj->string.length, + UTF16_LITTLE_ENDIAN, + buf, PAGE_SIZE); + buf[len] = '\n'; +} + +static int dsm_get_label(struct device *dev, char *buf, + enum acpi_attr_enum attr) +{ + acpi_handle handle; + union acpi_object *obj, *tmp; + int len = -1; + + handle = ACPI_HANDLE(dev); + if (!handle) + return -1; + + obj = acpi_evaluate_dsm(handle, device_label_dsm_uuid, 0x2, + DEVICE_LABEL_DSM, NULL); + if (!obj) + return -1; + + tmp = obj->package.elements; + if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 2 && + tmp[0].type == ACPI_TYPE_INTEGER && + tmp[1].type == ACPI_TYPE_STRING) { + /* + * 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); + + return len; +} + +static bool device_has_dsm(struct device *dev) +{ + 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 acpi_index_string_exist(struct kobject *kobj, + struct attribute *attr, int n) +{ + struct device *dev; + + dev = container_of(kobj, struct device, kobj); + + if (device_has_dsm(dev)) + return S_IRUGO; + + return 0; +} + +static ssize_t acpilabel_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return dsm_get_label(dev, buf, ACPI_ATTR_LABEL_SHOW); +} + +static ssize_t acpiindex_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return dsm_get_label(dev, buf, ACPI_ATTR_INDEX_SHOW); +} + +static struct device_attribute acpi_attr_label = { + .attr = {.name = "label", .mode = 0444}, + .show = acpilabel_show, +}; + +static struct device_attribute acpi_attr_index = { + .attr = {.name = "acpi_index", .mode = 0444}, + .show = acpiindex_show, +}; + +static struct attribute *acpi_attributes[] = { + &acpi_attr_label.attr, + &acpi_attr_index.attr, + NULL, +}; + +static struct attribute_group acpi_attr_group = { + .attrs = acpi_attributes, + .is_visible = acpi_index_string_exist, +}; + +static int pci_create_acpi_index_label_files(struct pci_dev *pdev) +{ + return sysfs_create_group(&pdev->dev.kobj, &acpi_attr_group); +} + +static int pci_remove_acpi_index_label_files(struct pci_dev *pdev) +{ + sysfs_remove_group(&pdev->dev.kobj, &acpi_attr_group); + return 0; +} +#else +static inline int pci_create_acpi_index_label_files(struct pci_dev *pdev) +{ + return -1; +} + +static inline int pci_remove_acpi_index_label_files(struct pci_dev *pdev) +{ + return -1; +} + +static inline bool device_has_dsm(struct device *dev) +{ + return false; +} +#endif void pci_create_firmware_label_files(struct pci_dev *pdev) { - if (!pci_create_smbiosname_file(pdev)) - ; + if (device_has_dsm(&pdev->dev)) + pci_create_acpi_index_label_files(pdev); + else + pci_create_smbiosname_file(pdev); } void pci_remove_firmware_label_files(struct pci_dev *pdev) { - pci_remove_smbiosname_file(pdev); + if (device_has_dsm(&pdev->dev)) + pci_remove_acpi_index_label_files(pdev); + else + pci_remove_smbiosname_file(pdev); } |