cs5530: add missing ->dma_base check

If ->dma_base is not set (== PCI BAR4 cannot be reserved) then DMA hooks
shouldn't be initialized or bad things will happen.

Also this host driver requires valid PCI BAR4 for normal operation so
check it in ->init_chipset and fail initialization if not set.

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

diff --git a/drivers/ide/pci/cs5530.c b/drivers/ide/pci/cs5530.c
index acaf71fd4c09b0feaacd53e6af3caaee03b3634c..e5949b1d3fb0c001726360ff2392f71c6edc303d 100644 (file)
--- a/drivers/ide/pci/cs5530.c
+++ b/drivers/ide/pci/cs5530.c
@@ -1,5 +1,5 @@
 /*
- * linux/drivers/ide/pci/cs5530.c              Version 0.73    Mar 10 2007
+ * linux/drivers/ide/pci/cs5530.c              Version 0.74    Jul 28 2007
  *
  * Copyright (C) 2000                  Andre Hedrick <andre@linux-ide.org>
  * Copyright (C) 2000                  Mark Lord <mlord@pobox.com>
@@ -207,6 +207,9 @@ static unsigned int __devinit init_chipset_cs5530 (struct pci_dev *dev, const ch
        struct pci_dev *master_0 = NULL, *cs5530_0 = NULL;
        unsigned long flags;
 
+       if (pci_resource_start(dev, 4) == 0)
+               return -EFAULT;
+
        dev = NULL;
        while ((dev = pci_get_device(PCI_VENDOR_ID_CYRIX, PCI_ANY_ID, dev)) != NULL) {
                switch (dev->device) {
@@ -325,6 +328,9 @@ static void __devinit init_hwif_cs5530 (ide_hwif_t *hwif)
                        /* needs autotuning later */
        }
 
+       if (hwif->dma_base == 0)
+               return;
+
        hwif->atapi_dma = 1;
        hwif->ultra_mask = 0x07;
        hwif->mwdma_mask = 0x07;