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 <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Mika Westerberg 2017-06-06 15:24:55 +03:00 committed by Greg Kroah-Hartman
parent 08a5e4cebe
commit df1421b5f7
1 changed files with 3 additions and 0 deletions

View File

@ -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)