diff options
| author | Matthew Wood <thepacketgeek@gmail.com> | 2025-09-17 05:58:14 -0700 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2025-09-17 10:53:36 -0500 |
| commit | cf6ee09b0913308729f9c38cfbcb8320c10fe5d5 (patch) | |
| tree | c1c130c4d6694feb024f08f6ca12e8a57c9ea190 /drivers/pci/pci-sysfs.c | |
| parent | fac679df7580979174c90303f004b09cdc6f086f (diff) | |
PCI/sysfs: Expose PCI device serial number
Add a single sysfs read-only interface for reading PCI device serial
numbers from userspace in a programmatic way. This device attribute uses
the same hexadecimal 1-byte dashed formatting as lspci serial number
capability output. If a device doesn't support the serial number
capability, the serial_number sysfs attribute will not be visible.
Signed-off-by: Matthew Wood <thepacketgeek@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mario Limonciello <superm1@kernel.org>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Link: https://patch.msgid.link/20250917125815.722952-2-thepacketgeek@gmail.com
Diffstat (limited to 'drivers/pci/pci-sysfs.c')
| -rw-r--r-- | drivers/pci/pci-sysfs.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index 5eea14c1f7f5..95d9c0145359 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -30,6 +30,7 @@ #include <linux/msi.h> #include <linux/of.h> #include <linux/aperture.h> +#include <linux/unaligned.h> #include "pci.h" #ifndef ARCH_PCI_DEV_GROUPS @@ -694,6 +695,22 @@ static ssize_t boot_vga_show(struct device *dev, struct device_attribute *attr, } static DEVICE_ATTR_RO(boot_vga); +static ssize_t serial_number_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct pci_dev *pci_dev = to_pci_dev(dev); + u64 dsn; + u8 bytes[8]; + + dsn = pci_get_dsn(pci_dev); + if (!dsn) + return -EIO; + + put_unaligned_be64(dsn, bytes); + return sysfs_emit(buf, "%8phD\n", bytes); +} +static DEVICE_ATTR_ADMIN_RO(serial_number); + static ssize_t pci_read_config(struct file *filp, struct kobject *kobj, const struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count) @@ -1698,6 +1715,7 @@ late_initcall(pci_sysfs_init); static struct attribute *pci_dev_dev_attrs[] = { &dev_attr_boot_vga.attr, + &dev_attr_serial_number.attr, NULL, }; @@ -1710,6 +1728,9 @@ static umode_t pci_dev_attrs_are_visible(struct kobject *kobj, if (a == &dev_attr_boot_vga.attr && pci_is_vga(pdev)) return a->mode; + if (a == &dev_attr_serial_number.attr && pci_get_dsn(pdev)) + return a->mode; + return 0; } |