Follow-up to commit 5c05ff68b9
("ide: switch to DMA-mapping API"):
* pci_{alloc,free}_consistent() -> dma_{alloc,free}_coherent()
in ide_{allocate,release}_dma_engine().
* Add ->prd_max_nents and ->prd_ent_size fields to ide_hwif_t
(+ set default values in ide_allocate_dma_engine()).
* Make ide_{allocate,release}_dma_engine() available also
for CONFIG_BLK_DEV_IDEDMA_SFF=n. Then convert au1xxx-ide.c,
scc_pata.c and sgiioc4.c to use them.
* Add missing ->init_dma method to scc_pata.
This patch also fixes:
- ->dmatable_cpu leak for au1xxx-ide
- too early realease of ->dmatable_cpu for scc_pata
- wrong amount of ->dmatable_cpu memory being freed for sgiioc4
While at it:
- remove superfluous ->dma_base check from ide_unregister()
- return -ENOMEM on error in ide_release_dma_engine()
- beautify error message in ide_release_dma_engine()
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>