tpm: fix compat 'ppi' link handling in tpm_chip_register()
authorJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Sat, 7 Nov 2015 11:33:25 +0000 (13:33 +0200)
committerJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Mon, 9 Nov 2015 15:52:56 +0000 (17:52 +0200)
commitd56e4f75346933dd2cb11533a668ce883908c859
tree943b7852ed98c6cf34ecf2fcd025f1476d86338a
parent2e31125c241212e2407d61a2d1cbdad0055a30b0
tpm: fix compat 'ppi' link handling in tpm_chip_register()

__compat_only_sysfs_link_entry_to_kobj() was unconditionally called for
TPM1 chips, which caused crash on Acer C720 laptop where DSM for the
ACPI object did not exist.

There are two reasons for unwanted behavior:

* The code did not check whether
  __compat_only_sysfs_link_entry_to_kobj() returned -ENOENT. This is
  OK. It just meanst that ppi is not available.
* The code did not clean up properly. Compat link should added only
  after all other init is done.

This patch sorts out these issues.

Fixes: 9b774d5cf2db
Reported-by: Jeremiah Mahler <jmmahler@gmail.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jeremiah Mahler <jmmahler@gmail.com>
Acked-by: Peter Huewe <PeterHuewe@gmx.de>
drivers/char/tpm/tpm-chip.c