ahci: give another shot at clearing all bits in irq_stat
authorTejun Heo <tj@kernel.org>
Sat, 5 Jul 2008 04:10:50 +0000 (13:10 +0900)
committerLinus Torvalds <torvalds@linux-foundation.org>
Sat, 5 Jul 2008 20:05:37 +0000 (13:05 -0700)
commitd28f87aa87ce8b196349d7c306a7e6fe3abd7155
treec6bc6d198536772cd50d08c6772e291c5ba91f31
parentd79df630f622806c4d0e116fbaf6ebf6baf53461
ahci: give another shot at clearing all bits in irq_stat

Commit ea0c62f7cf70f13a67830471b613337bd0c9a62e tried to clear all
bits in irq_stat but it didn't actually achieve that as irq_stat was
anded with port_map right after read.  This patch makes ahci driver
always use the unmasked value to clear irq_status.

While at it, add explanation on the peculiarities of ahci IRQ
clearing.

This was spotted by Linus Torvalds.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/ata/ahci.c