dm: pci: Tidy up auto-config error handling

When the auto-configuration process fails for a device (generally due to
lack of memory) we should return the error correctly so that we don't
continue to try memory allocations which will fail.

Adjust the code to check for errors and abort if something goes wrong.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

drivers/pci/pci-uclass.c

@@ -401,9 +401,13 @@ int pci_auto_config_devices(struct udevice *bus)
 	     !ret && dev;
 	     ret = device_find_next_child(&dev)) {
 		unsigned int max_bus;
+		int ret;
 
 		debug("%s: device %s\n", __func__, dev->name);
-		max_bus = pciauto_config_device(hose, pci_get_bdf(dev));
+		ret = pciauto_config_device(hose, pci_get_bdf(dev));
+		if (ret < 0)
+			return ret;
+		max_bus = ret;
 		sub_bus = max(sub_bus, max_bus);
 	}
 	debug("%s: done\n", __func__);
@@ -777,6 +781,8 @@ static int pci_uclass_post_probe(struct udevice *bus)
 
 #ifdef CONFIG_PCI_PNP
 	ret = pci_auto_config_devices(bus);
+	if (ret < 0)
+		return ret;
 #endif
 
 #if defined(CONFIG_X86) && defined(CONFIG_HAVE_FSP)
@@ -793,11 +799,14 @@ static int pci_uclass_post_probe(struct udevice *bus)
 	 * Note we only call this 1) after U-Boot is relocated, and 2)
 	 * root bus has finished probing.
 	 */
-	if ((gd->flags & GD_FLG_RELOC) && (bus->seq == 0))
+	if ((gd->flags & GD_FLG_RELOC) && (bus->seq == 0)) {
 		ret = fsp_init_phase_pci();
+		if (ret)
+			return ret;
+	}
 #endif
 
-	return ret < 0 ? ret : 0;
+	return 0;
 }
 
 static int pci_uclass_child_post_bind(struct udevice *dev)