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, 18 insertions, 0 deletions

diff --git a/drivers/pci/vpd.c b/drivers/pci/vpd.c
index 6bc554576f8d..a5a5ca17cfe6 100644
--- a/drivers/pci/vpd.c
+++ b/drivers/pci/vpd.c
@@ -41,3 +41,21 @@ int pci_vpd_find_tag(const u8 *buf, unsigned int off, unsigned int len, u8 rdt)
         return -ENOENT;
 }
 EXPORT_SYMBOL_GPL(pci_vpd_find_tag);
+
+int pci_vpd_find_info_keyword(const u8 *buf, unsigned int off,
+                              unsigned int len, const char *kw)
+{
+        int i;
+
+        for (i = off; i + PCI_VPD_INFO_FLD_HDR_SIZE <= off + len;) {
+                if (buf[i + 0] == kw[0] &&
+                    buf[i + 1] == kw[1])
+                        return i;
+
+                i += PCI_VPD_INFO_FLD_HDR_SIZE +
+                     pci_vpd_info_field_size(&buf[i]);
+        }
+
+        return -ENOENT;
+}
+EXPORT_SYMBOL_GPL(pci_vpd_find_info_keyword);