[PATCH ethtool 3/8] cmis: Fix printing of CDB EPL pages

[Ido Schimmel <idosch@nvidia.com>]

The "CdbMaxPagesEPL" field is 4-bits. The code currently assumes that
the value of the field directly determines the number of EPL pages, but
values 5 / 6 / 7 correspond to 8 / 12 / 16 EPL pages.

Fix the printing of the number of EPL pages by using a translation table
and avoid printing the field if the value is reserved (i.e., 8-15).

Fixes: fe8e296aa023 ("cmis: Print CDB messaging support advertisement")
Reviewed-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
---
 cmis.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/cmis.c b/cmis.c
index 16f168a3b1af..da1ced75e4ef 100644
--- a/cmis.c
+++ b/cmis.c
@@ -924,10 +924,14 @@ static void cmis_show_cdb_mode(const struct cmis_memory_map *map)
 
 static void cmis_show_cdb_epl_pages(const struct cmis_memory_map *map)
 {
-	__u8 epl_pages = map->page_01h[CMIS_CDB_ADVER_OFFSET] &
-			 CMIS_CDB_ADVER_EPL_MASK;
+	static const __u8 epl_page_count[] = { 0, 1, 2, 3, 4, 8, 12, 16 };
+	__u8 epl = map->page_01h[CMIS_CDB_ADVER_OFFSET] &
+		CMIS_CDB_ADVER_EPL_MASK;
 
-	module_print_any_uint("CDB EPL pages", epl_pages, NULL);
+	if (epl >= ARRAY_SIZE(epl_page_count))
+		return;
+
+	module_print_any_uint("CDB EPL pages", epl_page_count[epl], NULL);
 }
 
 static void cmis_show_cdb_rw_len(const struct cmis_memory_map *map)
-- 
2.55.0