pci: Add helper to find a VPD resource data type
This patch adds the pci_vpd_find_tag() helper function to find VPD
resource data types in a buffer.
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>
diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index 4df48d5..b2f6d77 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -4,7 +4,7 @@
obj-y += access.o bus.o probe.o remove.o pci.o quirks.o \
pci-driver.o search.o pci-sysfs.o rom.o setup-res.o \
- irq.o
+ irq.o vpd.o
obj-$(CONFIG_PROC_FS) += proc.o
obj-$(CONFIG_SYSFS) += slot.o
diff --git a/drivers/pci/vpd.c b/drivers/pci/vpd.c
new file mode 100644
index 0000000..6bc55457
--- /dev/null
+++ b/drivers/pci/vpd.c
@@ -0,0 +1,43 @@
+/*
+ * File: vpd.c
+ * Purpose: Provide PCI VPD support
+ *
+ * Copyright (C) 2010 Broadcom Corporation.
+ */
+
+#include <linux/pci.h>
+
+int pci_vpd_find_tag(const u8 *buf, unsigned int off, unsigned int len, u8 rdt)
+{
+ int i;
+
+ for (i = off; i < len; ) {
+ u8 val = buf[i];
+
+ if (val & PCI_VPD_LRDT) {
+ /* Don't return success of the tag isn't complete */
+ if (i + PCI_VPD_LRDT_TAG_SIZE > len)
+ break;
+
+ if (val == rdt)
+ return i;
+
+ i += PCI_VPD_LRDT_TAG_SIZE +
+ pci_vpd_lrdt_size(&buf[i]);
+ } else {
+ u8 tag = val & ~PCI_VPD_SRDT_LEN_MASK;
+
+ if (tag == rdt)
+ return i;
+
+ if (tag == PCI_VPD_SRDT_END)
+ break;
+
+ i += PCI_VPD_SRDT_TAG_SIZE +
+ pci_vpd_srdt_size(&buf[i]);
+ }
+ }
+
+ return -ENOENT;
+}
+EXPORT_SYMBOL_GPL(pci_vpd_find_tag);