tree 49d88b2f55bb88e5334979b418296af384149cda
parent a20c9e820864e18b59d2a4f2f04e8b6053986c95
author Tejun Heo <htejun@gmail.com> 1160386335 +0900
committer Jeff Garzik <jeff@garzik.org> 1165030828 -0500

[PATCH] libata: handle 0xff status properly

libata waits for !BSY even when the status register reports 0xff.
This causes long boot delays when D8 isn't pulled down properly.  This
patch does the followings.

* don't wait if status register is 0xff in all wait functions

* make ata_busy_sleep() return 0 on success and -errno on failure.
  -ENODEV is returned on 0xff status and -EBUSY on other failures.

* make ata_bus_softreset() succeed on 0xff status.  0xff status is not
  reset failure.  It indicates no device.  This removes unnecessary
  retries on such ports.  Note that the code change assumes unoccupied
  port reporting 0xff status does not produce valid device signature.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Joe Jin <lkmaillist@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>