Revert "serial/8250_pci: init-quirk msi support for kt serial controller"
commit1ae524187731d14da55b905fa6dbf3e975df7d99
authorDan Williams <dan.j.williams@intel.com>
Fri, 6 Apr 2012 18:49:37 +0000 (6 11:49 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 22 Apr 2012 22:38:57 +0000 (22 15:38 -0700)
tree1c26e6f5f68af712510b7785a3e0881b9e8e74b0
parent1b08b14dcb588eece73b7ee89c2dd68f5fb50998
Revert "serial/8250_pci: init-quirk msi support for kt serial controller"

commit 3579812373aba92b2f3b632bdf99329bc3c05d62 upstream.

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.

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