staging: comedi: me_daq: factor out the PLX bug workaround

Factor out the code in me_attach_pci() that handles the PLX-Bug
workaround to a separate function.

This looks odd. It appears that the bug workaround either swaps
PCI bars 0 and 5 or it modifies PCI bar 0. Shouldn't this happen
before PCI bar 0 is ioremap'ed?

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/drivers/me_daq.c b/drivers/staging/comedi/drivers/me_daq.c
index 95fbecc4929324fad6826d05fd3409d305448303..182a184604ee289720dbab6db26faaef89a52f09 100644 (file)
--- a/drivers/staging/comedi/drivers/me_daq.c
+++ b/drivers/staging/comedi/drivers/me_daq.c
@@ -617,6 +617,48 @@ static int me_reset(struct comedi_device *dev)
        return 0;
 }
 
+static int me_plx_bug_check(struct comedi_device *dev,
+                           struct pci_dev *pcidev)
+{
+       resource_size_t plx_regbase_tmp = pci_resource_start(pcidev, 0);
+       resource_size_t swap_regbase_tmp = pci_resource_start(pcidev, 5);
+       resource_size_t regbase_tmp;
+       int ret;
+
+       if (!swap_regbase_tmp)
+               dev_err(dev->class_dev, "Swap not present\n");
+
+       if (plx_regbase_tmp & 0x0080) {
+               dev_err(dev->class_dev, "PLX-Bug detected\n");
+
+               if (swap_regbase_tmp) {
+                       regbase_tmp = plx_regbase_tmp;
+                       plx_regbase_tmp = swap_regbase_tmp;
+                       swap_regbase_tmp = regbase_tmp;
+
+                       ret = pci_write_config_dword(pcidev,
+                                                    PCI_BASE_ADDRESS_0,
+                                                    plx_regbase_tmp);
+                       if (ret != PCIBIOS_SUCCESSFUL)
+                               return -EIO;
+
+                       ret = pci_write_config_dword(pcidev,
+                                                    PCI_BASE_ADDRESS_5,
+                                                    swap_regbase_tmp);
+                       if (ret != PCIBIOS_SUCCESSFUL)
+                               return -EIO;
+               } else {
+                       plx_regbase_tmp -= 0x80;
+                       ret = pci_write_config_dword(pcidev,
+                                                    PCI_BASE_ADDRESS_0,
+                                                    plx_regbase_tmp);
+                       if (ret != PCIBIOS_SUCCESSFUL)
+                               return -EIO;
+               }
+       }
+       return 0;
+}
+
 static const void *me_find_boardinfo(struct comedi_device *dev,
                                     struct pci_dev *pcidev)
 {
@@ -636,10 +678,6 @@ static int me_attach_pci(struct comedi_device *dev, struct pci_dev *pcidev)
        const struct me_board *board;
        struct me_private_data *dev_private;
        struct comedi_subdevice *s;
-       resource_size_t plx_regbase_tmp;
-       resource_size_t swap_regbase_tmp;
-       unsigned long swap_regbase_size_tmp;
-       resource_size_t regbase_tmp;
        int ret;
 
        board = me_find_boardinfo(dev, pcidev);
@@ -658,53 +696,14 @@ static int me_attach_pci(struct comedi_device *dev, struct pci_dev *pcidev)
                return ret;
        dev->iobase = 1;        /* detach needs this */
 
-       /* Read PLX register base address [PCI_BASE_ADDRESS #0]. */
-       plx_regbase_tmp = pci_resource_start(pcidev, 0);
-       dev_private->plx_regbase = ioremap(plx_regbase_tmp,
+       dev_private->plx_regbase = ioremap(pci_resource_start(pcidev, 0),
                                           pci_resource_len(pcidev, 0));
-       if (!dev_private->plx_regbase) {
-               dev_err(dev->class_dev, "Failed to remap I/O memory\n");
+       if (!dev_private->plx_regbase)
                return -ENOMEM;
-       }
-
-       /* Read Swap base address [PCI_BASE_ADDRESS #5]. */
-
-       swap_regbase_tmp = pci_resource_start(pcidev, 5);
-       swap_regbase_size_tmp = pci_resource_len(pcidev, 5);
-
-       if (!swap_regbase_tmp)
-               dev_err(dev->class_dev, "Swap not present\n");
-
-       /*---------------------------------------------- Workaround start ---*/
-       if (plx_regbase_tmp & 0x0080) {
-               dev_err(dev->class_dev, "PLX-Bug detected\n");
-
-               if (swap_regbase_tmp) {
-                       regbase_tmp = plx_regbase_tmp;
-                       plx_regbase_tmp = swap_regbase_tmp;
-                       swap_regbase_tmp = regbase_tmp;
 
-                       ret = pci_write_config_dword(pcidev,
-                                                       PCI_BASE_ADDRESS_0,
-                                                       plx_regbase_tmp);
-                       if (ret != PCIBIOS_SUCCESSFUL)
-                               return -EIO;
-
-                       ret = pci_write_config_dword(pcidev,
-                                                       PCI_BASE_ADDRESS_5,
-                                                       swap_regbase_tmp);
-                       if (ret != PCIBIOS_SUCCESSFUL)
-                               return -EIO;
-               } else {
-                       plx_regbase_tmp -= 0x80;
-                       ret = pci_write_config_dword(pcidev,
-                                                       PCI_BASE_ADDRESS_0,
-                                                       plx_regbase_tmp);
-                       if (ret != PCIBIOS_SUCCESSFUL)
-                               return -EIO;
-               }
-       }
-       /*--------------------------------------------- Workaround end -----*/
+       ret = me_plx_bug_check(dev, pcidev);
+       if (ret)
+               return ret;
 
        dev_private->me_regbase = ioremap(pci_resource_start(pcidev, 2),
                                          pci_resource_len(pcidev, 2));