pci: Add helper to search for VPD keywords

This patch adds the pci_vpd_find_info_keyword() helper function to
find information field keywords within read-only and read-write large
resource data type sections.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 17 insertions, 0 deletions

diff --git a/include/linux/pci.h b/include/linux/pci.h
index cfff32fc6e35..1f4a52131c99 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1375,6 +1375,10 @@ void pci_request_acs(void);
 
 #define PCI_VPD_INFO_FLD_HDR_SIZE       3
 
+#define PCI_VPD_RO_KEYWORD_PARTNO       "PN"
+#define PCI_VPD_RO_KEYWORD_MFR_ID       "MN"
+#define PCI_VPD_RO_KEYWORD_VENDOR0      "V0"
+
 /**
  * pci_vpd_lrdt_size - Extracts the Large Resource Data Type length
  * @lrdt: Pointer to the beginning of the Large Resource Data Type tag
@@ -1420,5 +1424,18 @@ static inline u8 pci_vpd_info_field_size(const u8 *info_field)
  */
 int pci_vpd_find_tag(const u8 *buf, unsigned int off, unsigned int len, u8 rdt);
 
+/**
+ * pci_vpd_find_info_keyword - Locates an information field keyword in the VPD
+ * @buf: Pointer to buffered vpd data
+ * @off: The offset into the buffer at which to begin the search
+ * @len: The length of the buffer area, relative to off, in which to search
+ * @kw: The keyword to search for
+ *
+ * Returns the index where the information field keyword was found or
+ * -ENOENT otherwise.
+ */
+int pci_vpd_find_info_keyword(const u8 *buf, unsigned int off,
+                              unsigned int len, const char *kw);
+
 #endif /* __KERNEL__ */
 #endif /* LINUX_PCI_H */