add ide-lib helpers

drivers/ide/ide-lib.c

+#include <linux/config.h>
+#define __NO_VERSION__
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/timer.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/major.h>
+#include <linux/errno.h>
+#include <linux/genhd.h>
+#include <linux/blkpg.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <linux/hdreg.h>
+#include <linux/ide.h>
+
+#include <asm/byteorder.h>
+#include <asm/irq.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+#include <asm/bitops.h>
+
+/*
+ *	IDE library routines. These are plug in code that most 
+ *	drivers can use but occasionally may be weird enough
+ *	to want to do their own thing with
+ *
+ *	Add common non I/O op stuff here. Make sure it has proper
+ *	kernel-doc function headers or your patch will be rejected
+ */
+ 
+
+/**
+ *	ide_xfer_verbose	-	return IDE mode names
+ *	@xfer_rate: rate to name
+ *
+ *	Returns a constant string giving the name of the mode
+ *	requested.
+ */
+
+char *ide_xfer_verbose (u8 xfer_rate)
+{
+        switch(xfer_rate) {
+                case XFER_UDMA_7:	return("UDMA 7");
+                case XFER_UDMA_6:	return("UDMA 6");
+                case XFER_UDMA_5:	return("UDMA 5");
+                case XFER_UDMA_4:	return("UDMA 4");
+                case XFER_UDMA_3:	return("UDMA 3");
+                case XFER_UDMA_2:	return("UDMA 2");
+                case XFER_UDMA_1:	return("UDMA 1");
+                case XFER_UDMA_0:	return("UDMA 0");
+                case XFER_MW_DMA_2:	return("MW DMA 2");
+                case XFER_MW_DMA_1:	return("MW DMA 1");
+                case XFER_MW_DMA_0:	return("MW DMA 0");
+                case XFER_SW_DMA_2:	return("SW DMA 2");
+                case XFER_SW_DMA_1:	return("SW DMA 1");
+                case XFER_SW_DMA_0:	return("SW DMA 0");
+                case XFER_PIO_4:	return("PIO 4");
+                case XFER_PIO_3:	return("PIO 3");
+                case XFER_PIO_2:	return("PIO 2");
+                case XFER_PIO_1:	return("PIO 1");
+                case XFER_PIO_0:	return("PIO 0");
+                case XFER_PIO_SLOW:	return("PIO SLOW");
+                default:		return("XFER ERROR");
+        }
+}
+
+EXPORT_SYMBOL(ide_xfer_verbose);
+
+/**
+ *	ide_dma_speed	-	compute DMA speed
+ *	@drive: drive
+ *	@mode; intended mode
+ *
+ *	Checks the drive capabilities and returns the speed to use
+ *	for the transfer. Returns -1 if the requested mode is unknown
+ *	(eg PIO)
+ */
+ 
+u8 ide_dma_speed(ide_drive_t *drive, u8 mode)
+{
+	struct hd_driveid *id   = drive->id;
+	ide_hwif_t *hwif	= HWIF(drive);
+	u8 speed = 0;
+
+	if (drive->media != ide_disk && hwif->atapi_dma == 0)
+		return 0;
+
+	switch(mode) {
+		case 0x04:
+			if ((id->dma_ultra & 0x0040) &&
+			    (id->dma_ultra & hwif->ultra_mask))
+				{ speed = XFER_UDMA_6; break; }
+		case 0x03:
+			if ((id->dma_ultra & 0x0020) &&
+			    (id->dma_ultra & hwif->ultra_mask))
+				{ speed = XFER_UDMA_5; break; }
+		case 0x02:
+			if ((id->dma_ultra & 0x0010) &&
+			    (id->dma_ultra & hwif->ultra_mask))
+				{ speed = XFER_UDMA_4; break; }
+			if ((id->dma_ultra & 0x0008) &&
+			    (id->dma_ultra & hwif->ultra_mask))
+				{ speed = XFER_UDMA_3; break; }
+		case 0x01:
+			if ((id->dma_ultra & 0x0004) &&
+			    (id->dma_ultra & hwif->ultra_mask))
+				{ speed = XFER_UDMA_2; break; }
+			if ((id->dma_ultra & 0x0002) &&
+			    (id->dma_ultra & hwif->ultra_mask))
+				{ speed = XFER_UDMA_1; break; }
+			if ((id->dma_ultra & 0x0001) &&
+			    (id->dma_ultra & hwif->ultra_mask))
+				{ speed = XFER_UDMA_0; break; }
+		case 0x00:
+			if ((id->dma_mword & 0x0004) &&
+			    (id->dma_mword & hwif->mwdma_mask))
+				{ speed = XFER_MW_DMA_2; break; }
+			if ((id->dma_mword & 0x0002) &&
+			    (id->dma_mword & hwif->mwdma_mask))
+				{ speed = XFER_MW_DMA_1; break; }
+			if ((id->dma_mword & 0x0001) &&
+			    (id->dma_mword & hwif->mwdma_mask))
+				{ speed = XFER_MW_DMA_0; break; }
+			if ((id->dma_1word & 0x0004) &&
+			    (id->dma_1word & hwif->swdma_mask))
+				{ speed = XFER_SW_DMA_2; break; }
+			if ((id->dma_1word & 0x0002) &&
+			    (id->dma_1word & hwif->swdma_mask))
+				{ speed = XFER_SW_DMA_1; break; }
+			if ((id->dma_1word & 0x0001) &&
+			    (id->dma_1word & hwif->swdma_mask))
+				{ speed = XFER_SW_DMA_0; break; }
+	}
+
+//	printk("%s: %s: mode 0x%02x, speed 0x%02x\n",
+//		__FUNCTION__, drive->name, mode, speed);
+
+	return speed;
+}
+
+EXPORT_SYMBOL(ide_dma_speed);
+
+
+/**
+ *	ide_rate_filter		-	return best speed for mode
+ *	@mode: modes available
+ *	@speed: desired speed
+ *
+ *	Given the available DMA/UDMA mode this function returns
+ *	the best available speed at or below the speed requested.
+ */
+
+u8 ide_rate_filter (u8 mode, u8 speed) 
+{
+#ifdef CONFIG_BLK_DEV_IDEDMA
+	static u8 speed_max[] = {
+		XFER_MW_DMA_2, XFER_UDMA_2, XFER_UDMA_4,
+		XFER_UDMA_5, XFER_UDMA_6
+	};
+
+//	printk("%s: mode 0x%02x, speed 0x%02x\n", __FUNCTION__, mode, speed);
+
+	/* So that we remember to update this if new modes appear */
+	if (mode > 4)
+		BUG();
+	return min(speed, speed_max[mode]);
+#else /* !CONFIG_BLK_DEV_IDEDMA */
+	return min(speed, XFER_PIO_4);
+#endif /* CONFIG_BLK_DEV_IDEDMA */
+}
+
+EXPORT_SYMBOL(ide_rate_filter);
+
+int ide_dma_enable (ide_drive_t *drive)
+{
+	ide_hwif_t *hwif	= HWIF(drive);
+	struct hd_driveid *id	= drive->id;
+
+	return ((int)	((((id->dma_ultra >> 8) & hwif->ultra_mask) ||
+			  ((id->dma_mword >> 8) & hwif->mwdma_mask) ||
+			  ((id->dma_1word >> 8) & hwif->swdma_mask)) ? 1 : 0));
+}
+
+EXPORT_SYMBOL(ide_dma_enable);