[PATCH 1/2] ata: pata_artop: read the ATP865 mode register through pci_iomap

[Daniel Palmer <daniel@0x0f.com>]

artop_init_one() probes the 6280's "fast" bit with inb() on the raw
start address of BAR 4.  That address is a PCI I/O address, which is
only a usable port number on platforms whose I/O port base maps PCI I/O
space one to one.  On an SH7751 LANDISK (identity io_port_base, PCI I/O
window at 0xfe240000) the resource starts at 0x1400 and inb(0x1400)
dereferences that address:

  BUG: unable to handle kernel paging request at 00001400
  PC is at artop_init_one+0x10e/0x170

Map the BAR with pci_iomap() and use ioread8(), as libata-sff does for
the BMDMA registers later on.

Signed-off-by: Daniel Palmer <daniel@0x0f.com>
---
 drivers/ata/pata_artop.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/ata/pata_artop.c b/drivers/ata/pata_artop.c
index 9f8d41639a62..351ff4c8e48e 100644
--- a/drivers/ata/pata_artop.c
+++ b/drivers/ata/pata_artop.c
@@ -405,13 +405,21 @@ static int artop_init_one (struct pci_dev *pdev, const struct pci_device_id *id)
 	case 1:		/* 6260 */
 		ppi[0] = &info_626x;
 		break;
-	case 2:		/* 6280 or 6280 + fast */
-		if (inb(pci_resource_start(pdev, 4)) & 0x10)
+	case 2: {	/* 6280 or 6280 + fast */
+		void __iomem *bmdma = pci_iomap(pdev, 4, 1);
+		u8 cfg;
+
+		if (!bmdma)
+			return -ENOMEM;
+		cfg = ioread8(bmdma);
+		pci_iounmap(pdev, bmdma);
+		if (cfg & 0x10)
 			ppi[0] = &info_628x_fast;
 		else
 			ppi[0] = &info_628x;
 		break;
 	}
+	}
 
 	BUG_ON(ppi[0] == NULL);
 
-- 
2.55.0