mtd: Blackfin NFC: fix nand busy detection
commitd2350c2ab51df7088d3db73a4c85ad73ded37a01
authorBarry Song <barry.song@analog.com>
Thu, 5 Aug 2010 15:07:38 +0000 (5 11:07 -0400)
committerDavid Woodhouse <David.Woodhouse@intel.com>
Thu, 5 Aug 2010 15:14:54 +0000 (5 16:14 +0100)
treed06f9e54f97f799097d220f66c23b0eab146c2ad
parent44299179c0e87cc6d8b753c1ca8c97b1cf9340e1
mtd: Blackfin NFC: fix nand busy detection

The IRQSTAT register is a W1C register used by the interrupt handler and
may have its BUSY bit changed.  This makes it somewhat unreliable for the
polling devready function.  So switch it over to use the BUSY bit in the
STAT register that always reflects the current state of the hardware.

This fixes driver hangs seen when the NAND flash is under heavy system
load (like I/O benchmarks).

Signed-off-by: Barry Song <barry.song@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
drivers/mtd/nand/bf5xx_nand.c