ide: config_drive_for_dma() fixes

* Add DMA blacklist checking (->ide_dma_on check probably can go now).

* Add ->atapi_dma flag checking and remove no longer needed
  ns87415_ide_dma_check() from ns87415 host driver.

* Remove now needless __ide_dma_check() wrapper and symbol export.

* Check drive->autodma instead of hwif->autodma (there should be no changes in
  behavior as all users of config_drive_for_dma() set both ->autodma flags).

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

drivers/ide/ide-dma.c

@@ -349,9 +349,17 @@ EXPORT_SYMBOL_GPL(ide_destroy_dmatable);
  
 static int config_drive_for_dma (ide_drive_t *drive)
 {
+	ide_hwif_t *hwif = drive->hwif;
 	struct hd_driveid *id = drive->id;
 
-	if ((id->capability & 1) && drive->hwif->autodma) {
+	/* consult the list of known "bad" drives */
+	if (__ide_dma_bad_drive(drive))
+		return -1;
+
+	if (drive->media != ide_disk && hwif->atapi_dma == 0)
+		return -1;
+
+	if ((id->capability & 1) && drive->autodma) {
 		/*
 		 * Enable DMA on any drive that has
 		 * UltraDMA (mode 0/1/2/3/4/5/6) enabled
@@ -513,20 +521,6 @@ int __ide_dma_on (ide_drive_t *drive)
 
 EXPORT_SYMBOL(__ide_dma_on);
 
-/**
- *	__ide_dma_check		-	check DMA setup
- *	@drive: drive to check
- *
- *	Don't use - due for extermination
- */
- 
-int __ide_dma_check (ide_drive_t *drive)
-{
-	return config_drive_for_dma(drive);
-}
-
-EXPORT_SYMBOL(__ide_dma_check);
-
 /**
  *	ide_dma_setup	-	begin a DMA phase
  *	@drive: target device
@@ -1021,7 +1015,7 @@ void ide_setup_dma (ide_hwif_t *hwif, unsigned long dma_base, unsigned int num_p
 	if (!hwif->dma_host_on)
 		hwif->dma_host_on = &ide_dma_host_on;
 	if (!hwif->ide_dma_check)
-		hwif->ide_dma_check = &__ide_dma_check;
+		hwif->ide_dma_check = &config_drive_for_dma;
 	if (!hwif->dma_setup)
 		hwif->dma_setup = &ide_dma_setup;
 	if (!hwif->dma_exec_cmd)