From df1421b5f72979e48096f68c253f59aa7e8e7468 Mon Sep 17 00:00:00 2001 From: Mika Westerberg Date: Tue, 6 Jun 2017 15:24:55 +0300 Subject: [PATCH] thunderbolt: Do not try to read UID if DROM offset is read as 0 At least Falcon Ridge when in host mode does not have any kind of DROM available and reading DROM offset returns 0 for these. Do not try to read DROM any further in that case. Signed-off-by: Mika Westerberg Reviewed-by: Yehezkel Bernat Reviewed-by: Michael Jamet Reviewed-by: Andy Shevchenko Signed-off-by: Andreas Noever Signed-off-by: Greg Kroah-Hartman --- drivers/thunderbolt/eeprom.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/thunderbolt/eeprom.c b/drivers/thunderbolt/eeprom.c index 6392990c984d..e4e64b130514 100644 --- a/drivers/thunderbolt/eeprom.c +++ b/drivers/thunderbolt/eeprom.c @@ -276,6 +276,9 @@ int tb_drom_read_uid_only(struct tb_switch *sw, u64 *uid) if (res) return res; + if (drom_offset == 0) + return -ENODEV; + /* read uid */ res = tb_eeprom_read_n(sw, drom_offset, data, 9); if (res) -- 2.20.1