[SCSI] aic7xxx: move to dma_get_required_mask() and correct 39 bit assumptions

This patch moves aic7xxx over to the dma_get_required_mask() API and
dumps its open coded memory check.

It also appears from this bug:

https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=167049

That 39 bit addressing doesn't work on older cards.  I surmise that the
AHC_LARGE_SCBS flag is the one that marks cards capable of using 39 bit
addressing, so I also folded that check into the code.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

3 files changed, 5 insertions, 14 deletions

diff --git a/drivers/scsi/aic7xxx/aic7xxx_osm.c b/drivers/scsi/aic7xxx/aic7xxx_osm.c
index c932b3b94490..876d1de8480d 100644
--- a/drivers/scsi/aic7xxx/aic7xxx_osm.c
+++ b/drivers/scsi/aic7xxx/aic7xxx_osm.c
@@ -1109,15 +1109,6 @@ ahc_linux_register_host(struct ahc_softc *ahc, struct scsi_host_template *templa
         return (0);
 }
 
-uint64_t
-ahc_linux_get_memsize(void)
-{
-        struct sysinfo si;
-
-        si_meminfo(&si);
-        return ((uint64_t)si.totalram << PAGE_SHIFT);
-}
-
 /*
  * Place the SCSI bus into a known state by either resetting it,
  * or forcing transfer negotiations on the next command to any
diff --git a/drivers/scsi/aic7xxx/aic7xxx_osm.h b/drivers/scsi/aic7xxx/aic7xxx_osm.h
index c52996269240..be9edbe26dbe 100644
--- a/drivers/scsi/aic7xxx/aic7xxx_osm.h
+++ b/drivers/scsi/aic7xxx/aic7xxx_osm.h
@@ -494,8 +494,6 @@ ahc_insb(struct ahc_softc * ahc, long port, uint8_t *array, int count)
 int             ahc_linux_register_host(struct ahc_softc *,
                                         struct scsi_host_template *);
 
-uint64_t        ahc_linux_get_memsize(void);
-
 /*************************** Pretty Printing **********************************/
 struct info_str {
         char *buffer;
diff --git a/drivers/scsi/aic7xxx/aic7xxx_osm_pci.c b/drivers/scsi/aic7xxx/aic7xxx_osm_pci.c
index 0d44a6907dd2..3ce77ddc889e 100644
--- a/drivers/scsi/aic7xxx/aic7xxx_osm_pci.c
+++ b/drivers/scsi/aic7xxx/aic7xxx_osm_pci.c
@@ -180,6 +180,7 @@ ahc_linux_pci_dev_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
         struct           ahc_pci_identity *entry;
         char            *name;
         int              error;
+        struct device   *dev = &pdev->dev;
 
         pci = pdev;
         entry = ahc_find_pci_device(pci);
@@ -209,11 +210,12 @@ ahc_linux_pci_dev_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
         pci_set_master(pdev);
 
         if (sizeof(dma_addr_t) > 4
-         && ahc_linux_get_memsize() > 0x80000000
-         && pci_set_dma_mask(pdev, mask_39bit) == 0) {
+            && ahc->features & AHC_LARGE_SCBS
+            && dma_set_mask(dev, mask_39bit) == 0
+            && dma_get_required_mask(dev) > DMA_32BIT_MASK) {
                 ahc->flags |= AHC_39BIT_ADDRESSING;
         } else {
-                if (pci_set_dma_mask(pdev, DMA_32BIT_MASK)) {
+                if (dma_set_mask(dev, DMA_32BIT_MASK)) {
                         printk(KERN_WARNING "aic7xxx: No suitable DMA available.\n");
                         return (-ENODEV);
                 }