Subject: [RFC PATCH 8/9] PCI: rpaphp: correctly match ibm, my-drc-index to drc-name when using drc-info

From: Tyrel Datwyler <[email-masked]>
Date: Tue, 1 Oct 2019 01:12:13 -0500

The newer ibm,drc-info property is a condensed description of the old
ibm,drc-* properties (ie. names, types, indexes, and power-domains).
When matching a drc-index to a drc-name we need to verify that the
index is within the start and last drc-index range and map it to a
drc-name using the drc-name-prefix and logical index.

Fix the mapping by checking that the index is within the range of the
current drc-info entry, and build the name form the drc-name-prefix
and by adding the starting drc-name-suffix value with the sequential
index of subtracting ibm,my-drc-index from this entries
drc-start-index.

Signed-off-by: Tyrel Datwyler <[email-masked]>
---
 drivers/pci/hotplug/rpaphp_core.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/hotplug/rpaphp_core.c b/drivers/pci/hotplug/rpaphp_core.c
index eabc0c51..5327606 100644
--- a/drivers/pci/hotplug/rpaphp_core.c
+++ b/drivers/pci/hotplug/rpaphp_core.c
@@ -248,9 +248,10 @@ static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
 		/* Should now know end of current entry */
 
 		/* Found it */
-		if (my_index <= drc.last_drc_index) {
+		if (my_index >= drc.drc_index_start && my_index <= drc.last_drc_index) {
+			int index = my_index - drc.drc_index_start;
 			sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix,
-				my_index);
+				drc.drc_name_suffix_start + index);
 			break;
 		}
 	}
-- 
2.7.4