diff --git a/drivers/pci/vpd.c b/drivers/pci/vpd.c index b1d012900f1e43f4e4870e714ac40b3a9dfcad5d..01e57594781e08315210143df1fe4dbfb43ff582 100644 --- a/drivers/pci/vpd.c +++ b/drivers/pci/vpd.c @@ -413,6 +413,29 @@ int pci_vpd_find_ro_info_keyword(const void *buf, unsigned int len, } EXPORT_SYMBOL_GPL(pci_vpd_find_ro_info_keyword); +int pci_vpd_check_csum(const void *buf, unsigned int len) +{ + const u8 *vpd = buf; + unsigned int size; + u8 csum = 0; + int rv_start; + + rv_start = pci_vpd_find_ro_info_keyword(buf, len, PCI_VPD_RO_KEYWORD_CHKSUM, &size); + if (rv_start == -ENOENT) /* no checksum in VPD */ + return 1; + else if (rv_start < 0) + return rv_start; + + if (!size) + return -EINVAL; + + while (rv_start >= 0) + csum += vpd[rv_start--]; + + return csum ? -EILSEQ : 0; +} +EXPORT_SYMBOL_GPL(pci_vpd_check_csum); + #ifdef CONFIG_PCI_QUIRKS /* * Quirk non-zero PCI functions to route VPD access through function 0 for diff --git a/include/linux/pci.h b/include/linux/pci.h index 9e3b60963a52b851c1c3cc0d404494fcd8db275d..827b7eefd550777a959c9bd6dafc2501633fabd7 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -2376,6 +2376,15 @@ int pci_vpd_find_info_keyword(const u8 *buf, unsigned int off, int pci_vpd_find_ro_info_keyword(const void *buf, unsigned int len, const char *kw, unsigned int *size); +/** + * pci_vpd_check_csum - Check VPD checksum + * @buf: Pointer to buffered VPD data + * @len: VPD size + * + * Returns 1 if VPD has no checksum, otherwise 0 or an errno + */ +int pci_vpd_check_csum(const void *buf, unsigned int len); + /* PCI <-> OF binding helpers */ #ifdef CONFIG_OF struct device_node;