[PATCH] Enable cdrom dma access with pdc20265_old

This patch allows me to use dma with my cd/dvd attached to my on board
pdc20265 ide controller

Alan sayeth:

  Looks sane.  Would be nice to know if there is any documentation
  supporting this hack being safe but the logic makes sense.  The LBA48 case
  faces the same problem - the state machine gets confused about the transfer
  length and needs kicking

Signed-off-by: Tobias Oed <tobiasoed@hotmail.com>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Cc: Jens Axboe <axboe@suse.de>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/drivers/ide/pci/pdc202xx_old.c b/drivers/ide/pci/pdc202xx_old.c
index b46022a..184cdac 100644 (file)
--- a/drivers/ide/pci/pdc202xx_old.c
+++ b/drivers/ide/pci/pdc202xx_old.c
@@ -154,7 +154,8 @@ static int pdc202xx_tune_chipset (ide_drive_t *drive, u8 xferspeed)
        u8                      AP, BP, CP, DP;
        u8                      TA = 0, TB = 0, TC = 0;
 
-       if ((drive->media != ide_disk) && (speed < XFER_SW_DMA_0))
+       if (drive->media != ide_disk &&
+               drive->media != ide_cdrom && speed < XFER_SW_DMA_0)
                return -1;
 
        pci_read_config_dword(dev, drive_pci, &drive_conf);
@@ -330,14 +331,12 @@ static int config_chipset_for_dma (ide_drive_t *drive)
 
 chipset_is_set:
 
-       if (drive->media == ide_disk) {
-               pci_read_config_byte(dev, (drive_pci), &AP);
-               if (id->capability & 4) /* IORDY_EN */
-                       pci_write_config_byte(dev, (drive_pci), AP|IORDY_EN);
-               pci_read_config_byte(dev, (drive_pci), &AP);
-               if (drive->media == ide_disk)   /* PREFETCH_EN */
-                       pci_write_config_byte(dev, (drive_pci), AP|PREFETCH_EN);
-       }
+       pci_read_config_byte(dev, (drive_pci), &AP);
+       if (id->capability & 4) /* IORDY_EN */
+               pci_write_config_byte(dev, (drive_pci), AP|IORDY_EN);
+       pci_read_config_byte(dev, (drive_pci), &AP);
+       if (drive->media == ide_disk)   /* PREFETCH_EN */
+               pci_write_config_byte(dev, (drive_pci), AP|PREFETCH_EN);
 
        speed = ide_dma_speed(drive, pdc202xx_ratemask(drive));
 
@@ -385,7 +384,7 @@ static void pdc202xx_old_ide_dma_start(ide_drive_t *drive)
 {
        if (drive->current_speed > XFER_UDMA_2)
                pdc_old_enable_66MHz_clock(drive->hwif);
-       if (drive->addressing == 1) {
+       if (drive->media != ide_disk || drive->addressing == 1) {
                struct request *rq      = HWGROUP(drive)->rq;
                ide_hwif_t *hwif        = HWIF(drive);
                unsigned long high_16   = hwif->dma_master;
@@ -405,7 +404,7 @@ static void pdc202xx_old_ide_dma_start(ide_drive_t *drive)
 
 static int pdc202xx_old_ide_dma_end(ide_drive_t *drive)
 {
-       if (drive->addressing == 1) {
+       if (drive->media != ide_disk || drive->addressing == 1) {
                ide_hwif_t *hwif        = HWIF(drive);
                unsigned long high_16   = hwif->dma_master;
                unsigned long atapi_reg = high_16 + (hwif->channel ? 0x24 : 0x20);
@@ -519,6 +518,7 @@ static void __devinit init_hwif_pdc202xx(ide_hwif_t *hwif)
        hwif->ultra_mask = 0x3f;
        hwif->mwdma_mask = 0x07;
        hwif->swdma_mask = 0x07;
+       hwif->atapi_dma = 1;
 
        hwif->err_stops_fifo = 1;