mfd: lpc_ich: Factor out lpc_ich_enable_spi_write()

Factor out duplicate code to lpc_ich_enable_spi_write() helper function.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Henning Schild <henning.schild@siemens.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee@kernel.org>

drivers/mfd/lpc_ich.c

@@ -1100,35 +1100,32 @@ static bool lpc_ich_byt_set_writeable(void __iomem *base, void *data)
 	return val & BYT_BCR_WPD;
 }
 
-static bool lpc_ich_lpt_set_writeable(void __iomem *base, void *data)
+static bool lpc_ich_set_writeable(struct pci_bus *bus, unsigned int devfn)
 {
-	struct pci_dev *pdev = data;
 	u32 bcr;
 
-	pci_read_config_dword(pdev, BCR, &bcr);
+	pci_bus_read_config_dword(bus, devfn, BCR, &bcr);
 	if (!(bcr & BCR_WPD)) {
 		bcr |= BCR_WPD;
-		pci_write_config_dword(pdev, BCR, bcr);
-		pci_read_config_dword(pdev, BCR, &bcr);
+		pci_bus_write_config_dword(bus, devfn, BCR, bcr);
+		pci_bus_read_config_dword(bus, devfn, BCR, &bcr);
 	}
 
 	return bcr & BCR_WPD;
 }
 
-static bool lpc_ich_bxt_set_writeable(void __iomem *base, void *data)
+static bool lpc_ich_lpt_set_writeable(void __iomem *base, void *data)
 {
-	unsigned int spi = PCI_DEVFN(13, 2);
-	struct pci_bus *bus = data;
-	u32 bcr;
+	struct pci_dev *pdev = data;
 
-	pci_bus_read_config_dword(bus, spi, BCR, &bcr);
-	if (!(bcr & BCR_WPD)) {
-		bcr |= BCR_WPD;
-		pci_bus_write_config_dword(bus, spi, BCR, bcr);
-		pci_bus_read_config_dword(bus, spi, BCR, &bcr);
-	}
+	return lpc_ich_set_writeable(pdev->bus, pdev->devfn);
+}
 
-	return bcr & BCR_WPD;
+static bool lpc_ich_bxt_set_writeable(void __iomem *base, void *data)
+{
+	struct pci_dev *pdev = data;
+
+	return lpc_ich_set_writeable(pdev->bus, PCI_DEVFN(13, 2));
 }
 
 static int lpc_ich_init_spi(struct pci_dev *dev)
@@ -1185,7 +1182,7 @@ static int lpc_ich_init_spi(struct pci_dev *dev)
 			res->end = res->start + SPIBASE_APL_SZ - 1;
 
 			info->set_writeable = lpc_ich_bxt_set_writeable;
-			info->data = bus;
+			info->data = dev;
 		}
 
 		pci_bus_write_config_byte(bus, p2sb, 0xe1, 0x1);