hpt366: MWDMA filter for SATA cards (take 2)

The Marvell bridge chips used on HighPoint SATA cards do not seem to support
the MWDMA modes (at least that could be seen in their so-called drivers :-),
so the driver needs to account for this -- to achieve this:

- add mdma_filter() method from the original patch by Bartlomiej Zolnierkiewicz
  with his consent;

- install the method for all chips to only return empty mask if a SATA drive
  is detected on HPT372{AN]/374 chips...
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

drivers/ide/ide-dma.c

@@ -673,8 +673,13 @@ static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base)
 			mask &= 0x07;
 		break;
 	case XFER_MW_DMA_0:
-		if (id->field_valid & 2)
-			mask = id->dma_mword & hwif->mwdma_mask;
+		if ((id->field_valid & 2) == 0)
+			break;
+		if (hwif->mdma_filter)
+			mask = hwif->mdma_filter(drive);
+		else
+			mask = hwif->mwdma_mask;
+		mask &= id->dma_mword;
 		break;
 	case XFER_SW_DMA_0:
 		if (id->field_valid & 2) {

drivers/ide/ide.c

@@ -398,6 +398,7 @@ static void ide_hwif_restore(ide_hwif_t *hwif, ide_hwif_t *tmp_hwif)
 
 	hwif->tuneproc			= tmp_hwif->tuneproc;
 	hwif->speedproc			= tmp_hwif->speedproc;
+	hwif->mdma_filter		= tmp_hwif->mdma_filter;
 	hwif->udma_filter		= tmp_hwif->udma_filter;
 	hwif->selectproc		= tmp_hwif->selectproc;
 	hwif->reset_poll		= tmp_hwif->reset_poll;

drivers/ide/pci/hpt366.c

 /*
- * linux/drivers/ide/pci/hpt366.c		Version 1.12	Aug 19, 2007
+ * linux/drivers/ide/pci/hpt366.c		Version 1.13	Sep 29, 2007
  *
  * Copyright (C) 1999-2003		Andre Hedrick <andre@linux-ide.org>
  * Portions Copyright (C) 2001	        Sun Microsystems, Inc.
@@ -114,7 +114,7 @@
  *   unify HPT36x/37x timing setup code and the speedproc handlers by joining
  *   the register setting lists into the table indexed by the clock selected
  * - set the correct hwif->ultra_mask for each individual chip
- * - add UltraDMA mode filtering for the HPT37[24] based SATA cards
+ * - add Ultra and MW DMA mode filtering for the HPT37[24] based SATA cards
  *	Sergei Shtylyov, <sshtylyov@ru.mvista.com> or <source@mvista.com>
  */
 
@@ -562,6 +562,24 @@ static u8 hpt3xx_udma_filter(ide_drive_t *drive)
 	return check_in_drive_list(drive, bad_ata33) ? 0x00 : mask;
 }
 
+static u8 hpt3xx_mdma_filter(ide_drive_t *drive)
+{
+	ide_hwif_t *hwif	= HWIF(drive);
+	struct hpt_info *info	= pci_get_drvdata(hwif->pci_dev);
+
+	switch (info->chip_type) {
+	case HPT372 :
+	case HPT372A:
+	case HPT372N:
+	case HPT374 :
+		if (ide_dev_is_sata(drive->id))
+			return 0x00;
+		/* Fall thru */
+	default:
+		return 0x07;
+	}
+}
+
 static u32 get_speed_setting(u8 speed, struct hpt_info *info)
 {
 	int i;
@@ -1257,6 +1275,7 @@ static void __devinit init_hwif_hpt366(ide_hwif_t *hwif)
 	hwif->busproc		= &hpt3xx_busproc;
 
 	hwif->udma_filter	= &hpt3xx_udma_filter;
+	hwif->mdma_filter	= &hpt3xx_mdma_filter;
 
 	/*
 	 * HPT3xxN chips have some complications:

include/linux/ide.h

@@ -723,6 +723,7 @@ typedef struct hwif_s {
 	/* driver soft-power interface */
 	int	(*busproc)(ide_drive_t *, int);
 #endif
+	u8 (*mdma_filter)(ide_drive_t *);
 	u8 (*udma_filter)(ide_drive_t *);
 
 	void (*ata_input_data)(ide_drive_t *, void *, u32);