drivers/pci/pci-label.c - arm/linux-arm64-legacy - Git at Google

 /*
  * Purpose: Export the firmware instance and label associated with
  * a pci device to sysfs
  * Copyright (C) 2010 Dell Inc.
  * 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.
  *
  * Please see http://linux.dell.com/wiki/index.php/Oss/libnetdevname for more
  * information.
  */

 #include <linux/dmi.h>
 #include <linux/sysfs.h>
 #include <linux/pci.h>
 #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 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;
 	int bus;
 	int devfn;

 	bus = pdev->bus->number;
 	devfn = pdev->devfn;

 	dmi = NULL;
 	while ((dmi = dmi_find_device(DMI_DEV_TYPE_DEV_ONBOARD,
 				      NULL, dmi)) != NULL) {
 		donboard = dmi->device_data;
 		if (donboard && donboard->bus == bus &&
 					donboard->devfn == devfn) {
 			if (buf) {
 				if (attribute == SMBIOS_ATTR_INSTANCE_SHOW)
 					return scnprintf(buf, PAGE_SIZE,
 							 "%d\n",
 							 donboard->instance);
 				else if (attribute == SMBIOS_ATTR_LABEL_SHOW)
 					return scnprintf(buf, PAGE_SIZE,
 							 "%s\n",
 							 dmi->name);
 			}
 			return strlen(dmi->name);
 		}
 	}
 	return 0;
 }

 static umode_t smbios_instance_string_exist(struct kobject *kobj,
 					    struct attribute *attr, int n)
 {
 	struct device *dev;
 	struct pci_dev *pdev;

 	dev = container_of(kobj, struct device, kobj);
 	pdev = to_pci_dev(dev);

 	return find_smbios_instance_string(pdev, NULL, SMBIOS_ATTR_NONE) ?
 					   S_IRUGO : 0;
 }

 static ssize_t smbioslabel_show(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
 	struct pci_dev *pdev;
 	pdev = to_pci_dev(dev);

 	return find_smbios_instance_string(pdev, buf,
 					   SMBIOS_ATTR_LABEL_SHOW);
 }

 static ssize_t smbiosinstance_show(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
 	struct pci_dev *pdev;
 	pdev = to_pci_dev(dev);

 	return find_smbios_instance_string(pdev, buf,
 					   SMBIOS_ATTR_INSTANCE_SHOW);
 }

 static struct device_attribute smbios_attr_label = {
 	.attr = {.name = "label", .mode = 0444},
 	.show = smbioslabel_show,
 };

 static struct device_attribute smbios_attr_instance = {
 	.attr = {.name = "index", .mode = 0444},
 	.show = smbiosinstance_show,
 };

 static struct attribute *smbios_attributes[] = {
 	&smbios_attr_label.attr,
 	&smbios_attr_instance.attr,
 	NULL,
 };

 static struct attribute_group smbios_attr_group = {
 	.attrs = smbios_attributes,
 	.is_visible = smbios_instance_string_exist,
 };

 static int pci_create_smbiosname_file(struct pci_dev *pdev)
 {
 	return sysfs_create_group(&pdev->dev.kobj, &smbios_attr_group);
 }

 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 (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)
 {
 	if (device_has_dsm(&pdev->dev))
 		pci_remove_acpi_index_label_files(pdev);
 	else
 		pci_remove_smbiosname_file(pdev);
 }
	/*
	* Purpose: Export the firmware instance and label associated with
	* a pci device to sysfs
	* Copyright (C) 2010 Dell Inc.
	* 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.
	*
	* Please see http://linux.dell.com/wiki/index.php/Oss/libnetdevname for more
	* information.
	*/

	#include <linux/dmi.h>
	#include <linux/sysfs.h>
	#include <linux/pci.h>
	#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 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;
	int bus;
	int devfn;

	bus = pdev->bus->number;
	devfn = pdev->devfn;

	dmi = NULL;
	while ((dmi = dmi_find_device(DMI_DEV_TYPE_DEV_ONBOARD,
	NULL, dmi)) != NULL) {
	donboard = dmi->device_data;
	if (donboard && donboard->bus == bus &&
	donboard->devfn == devfn) {
	if (buf) {
	if (attribute == SMBIOS_ATTR_INSTANCE_SHOW)
	return scnprintf(buf, PAGE_SIZE,
	"%d\n",
	donboard->instance);
	else if (attribute == SMBIOS_ATTR_LABEL_SHOW)
	return scnprintf(buf, PAGE_SIZE,
	"%s\n",
	dmi->name);
	}
	return strlen(dmi->name);
	}
	}
	return 0;
	}

	static umode_t smbios_instance_string_exist(struct kobject *kobj,
	struct attribute *attr, int n)
	{
	struct device *dev;
	struct pci_dev *pdev;

	dev = container_of(kobj, struct device, kobj);
	pdev = to_pci_dev(dev);

	return find_smbios_instance_string(pdev, NULL, SMBIOS_ATTR_NONE) ?
	S_IRUGO : 0;
	}

	static ssize_t smbioslabel_show(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct pci_dev *pdev;
	pdev = to_pci_dev(dev);

	return find_smbios_instance_string(pdev, buf,
	SMBIOS_ATTR_LABEL_SHOW);
	}

	static ssize_t smbiosinstance_show(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct pci_dev *pdev;
	pdev = to_pci_dev(dev);

	return find_smbios_instance_string(pdev, buf,
	SMBIOS_ATTR_INSTANCE_SHOW);
	}

	static struct device_attribute smbios_attr_label = {
	.attr = {.name = "label", .mode = 0444},
	.show = smbioslabel_show,
	};

	static struct device_attribute smbios_attr_instance = {
	.attr = {.name = "index", .mode = 0444},
	.show = smbiosinstance_show,
	};

	static struct attribute *smbios_attributes[] = {
	&smbios_attr_label.attr,
	&smbios_attr_instance.attr,
	NULL,
	};

	static struct attribute_group smbios_attr_group = {
	.attrs = smbios_attributes,
	.is_visible = smbios_instance_string_exist,
	};

	static int pci_create_smbiosname_file(struct pci_dev *pdev)
	{
	return sysfs_create_group(&pdev->dev.kobj, &smbios_attr_group);
	}

	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 (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)
	{
	if (device_has_dsm(&pdev->dev))
	pci_remove_acpi_index_label_files(pdev);
	else
	pci_remove_smbiosname_file(pdev);
	}