This reverts commit e86ff4a63c9fdd875ba8492577cd1ad2252f525c.
This tried to enforce the semantics of one interrupt per iir read of the
THRE (transmit-hold empty) status, but events from other sources
(particularly modem status) defeat this guarantee.
This change also broke 8250_pci suspend/resume support as
pciserial_resume_ports() re-runs .init() quirks, but does not run
.exit() quirks in pciserial_suspend_ports() leading to reports like:
sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:16.3/msi_irqs'
...and a subsequent crash. The mismatch of init/exit at suspend/resume
seems like a bug in its own right.
[stable: 3.3.x]
Cc: stable <stable@vger.kernel.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Cc: Sudhakar Mamillapalli <sudhakar@fb.com>
Reported-by: Nhan H Mai <nhan.h.mai@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
3579812373