drm/via: Rename cx700_mem_type() to p4m900_mem_type()

The function will now acquire a pointer to the relevant PCI bridge
device within it.  Improved its error handling within the function.

Signed-off-by: Kevin Brace <kevinbrace@bracecomputerlab.com>

1 files changed, 43 insertions, 23 deletions

diff --git a/drivers/gpu/drm/via/via_init.c b/drivers/gpu/drm/via/via_init.c
index f242ce7da9a1..3c36a8b4252a 100644
--- a/drivers/gpu/drm/via/via_init.c
+++ b/drivers/gpu/drm/via/via_init.c
@@ -756,63 +756,83 @@ exit:
 	return ret;
 }
 
-static int cx700_mem_type(struct drm_device *dev,
-				struct pci_dev *fn3)
+static int p4m900_mem_type(struct drm_device *dev)
 {
+	struct pci_dev *gfx_dev = to_pci_dev(dev->dev);
+	struct pci_dev *bridge_fn3_dev;
 	struct via_drm_priv *dev_priv = to_via_drm_priv(dev);
 	u8 type, clock;
 	int ret;
 
-	ret = pci_read_config_byte(fn3, 0x90, &clock);
-	if (ret)
-		return ret;
-	ret = pci_read_config_byte(fn3, 0x6c, &type);
-	if (ret)
-		return ret;
+	bridge_fn3_dev =
+		pci_get_domain_bus_and_slot(pci_domain_nr(gfx_dev->bus), 0,
+						PCI_DEVFN(0, 3));
+	if (!bridge_fn3_dev) {
+		ret = -ENODEV;
+		drm_err(dev, "Host Bridge Function 3 not found! errno: %d\n",
+			ret);
+		goto exit;
+	}
+
+	ret = pci_read_config_byte(bridge_fn3_dev, 0x6c, &type);
+	if (ret) {
+		goto error_pci_cfg_read;
+	}
+
+	ret = pci_read_config_byte(bridge_fn3_dev, 0x90, &clock);
+	if (ret) {
+		goto error_pci_cfg_read;
+	}
+
 	type &= 0x40;
 	type >>= 6;
-
 	switch (type) {
-	case 0:
+	case 0x00:
 		switch (clock & 0x07) {
-		case 0:
+		case 0x00:
 			dev_priv->vram_type = VIA_MEM_DDR_200;
 			break;
-		case 1:
+		case 0x01:
 			dev_priv->vram_type = VIA_MEM_DDR_266;
 			break;
-		case 2:
+		case 0x02:
 			dev_priv->vram_type = VIA_MEM_DDR_333;
 			break;
-		case 3:
+		case 0x03:
 			dev_priv->vram_type = VIA_MEM_DDR_400;
 			break;
 		default:
 			break;
 		}
-		break;
 
-	case 1:
+		break;
+	case 0x01:
 		switch (clock & 0x07) {
-		case 3:
+		case 0x03:
 			dev_priv->vram_type = VIA_MEM_DDR2_400;
 			break;
-		case 4:
+		case 0x04:
 			dev_priv->vram_type = VIA_MEM_DDR2_533;
 			break;
-		case 5:
+		case 0x05:
 			dev_priv->vram_type = VIA_MEM_DDR2_667;
 			break;
-		case 6:
+		case 0x06:
 			dev_priv->vram_type = VIA_MEM_DDR2_800;
 			break;
 		default:
 			break;
 		}
+
 		break;
 	default:
 		break;
 	}
+
+	goto exit;
+error_pci_cfg_read:
+	drm_err(dev, "PCI configuration space read error! errno: %d\n", ret);
+exit:
 	return ret;
 }
 
@@ -1054,8 +1074,6 @@ static int via_vram_init(struct drm_device *dev)
 
 	/* P4M800CE / P4M800 Pro / VN800 / CN700 */
 	case PCI_DEVICE_ID_VIA_P4M800CE:
-	/* P4M900 / VN896 / CN896 */
-	case PCI_DEVICE_ID_VIA_VT3364:
 		ret = pci_read_config_byte(hb_fn3, 0xa1, &size);
 		if (ret)
 			goto error_hb_fn3;
@@ -1073,6 +1091,8 @@ static int via_vram_init(struct drm_device *dev)
 	case PCI_DEVICE_ID_VIA_VT3324:
 	/* P4M890 / VN890 */
 	case PCI_DEVICE_ID_VIA_P4M890:
+	/* P4M900 / VN896 / CN896 */
+	case PCI_DEVICE_ID_VIA_VT3364:
 	/* VX800 / VX820 */
 	case PCI_DEVICE_ID_VIA_VX800_HB:
 	/* VX855 / VX875 */
@@ -1082,7 +1102,7 @@ static int via_vram_init(struct drm_device *dev)
 			goto error_hb_fn3;
 		dev_priv->vram_size = (1 << ((size & 0x70) >> 4)) << 22;
 
-		ret = cx700_mem_type(dev, hb_fn3);
+		ret = p4m900_mem_type(dev);
 		if (ret)
 			goto error_hb_fn3;
 		break;