Revert "serial/8250_pci: init-quirk msi support for kt serial controller"
authorDan Williams <dan.j.williams@intel.com>
Fri, 6 Apr 2012 18:49:37 +0000 (11:49 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 9 Apr 2012 17:34:16 +0000 (10:34 -0700)
commit3579812373aba92b2f3b632bdf99329bc3c05d62
tree341f3624f6a00813f9245832bb6a17a130d323f3
parentd8c4019b41aaf4d6401a4ceb3819b8e1afe21595
Revert "serial/8250_pci: init-quirk msi support for kt serial controller"

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>
drivers/tty/serial/8250/8250_pci.c