PCI/ASPM: Make sysfs link_state_store() consistent with link_state_show()
If CONFIG_PCIEASPM_DEBUG is set, then PCI devices have a link_state
attribute. Reading that attribute shows the state as a bit mask: 1
means L0S upstream, 2 means L0S downstream, and 4 means L1.
Oddly, writing to link_state is inconsistent and gets translated, leading
to mysterious results in which the value you store isn't comparable the
value you load back out.
Fix it by making link_state_store() match link_state_show().
[bhelgaas: Check "aspm_disabled" *before* validating input. When
"aspm_disabled" is set, this changes the error for invalid input from
-EINVAL to -EPERM.]
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
1 file changed